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• 12291. [Article] Vitamin E and K interactions : investigating mechanisms of reduced vitamin K status in response to excess vitamin E

  The primary goal of my studies was to elucidate the mechanisms for the well-recognized interaction between two nutrients, vitamins E and K. The outcomes from my studies assess mechanisms for adverse effects ...

  Citation × Citation Citation Abstract Copy Title: Vitamin E and K interactions : investigating mechanisms of reduced vitamin K status in response to excess vitamin E Author: Farley, Sherry Mae The primary goal of my studies was to elucidate the mechanisms for the well-recognized interaction between two nutrients, vitamins E and K. The outcomes from my studies assess mechanisms for adverse effects of vitamin E and provide novel information on mechanisms for vitamin K homeostasis. These findings will provide information relevant for assessing optimal intakes of vitamins E and K. This dissertation presents studies aimed at evaluating three different mechanisms by which vitamin K status could be decreased by increases in whole body vitamin E concentrations in rats supplemented with vitamin E by subcutaneous injections (100 mg α-tocopherol (α-T)/ kg body weight per day), the model system developed in the Traber lab. The tested mechanisms by which vitamin E leads to reduced vitamin K status were: 1) increasing vitamin K metabolism, 2) decreasing menaquinone-4 (MK-4) synthesis from dietary phylloquinone (PK) and 3) potentiating vitamin K excretion through xenobiotic pathways. Two approaches were undertaken to evaluate the hypothesis that vitamin E increases vitamin K metabolism. In Aim 1.1, the in vitro omega-hydroxylation of vitamin K by human cytochrome P450 CYP4F2 (expressed in insect microsomes) was tested because CYP4F2 is considered the limiting step in the catabolism of both vitamins. Chapter 2 shows that CYP4F2 more rapidly hydroxylated vitamin K compared with vitamin E. Moreover, vitamin E did not stimulate vitamin K metabolism in vitro. Thus, it is unlikely vitamin E stimulates vitamin K metabolism in vivo by direct interaction with the CYP4F2 enzyme-substrate complex. In Aim 1.2, the in vivo urinary and biliary excretion of vitamin K metabolites was investigated. Chapter 3 shows that α-T-injected rats significantly increased urinary excretion of vitamin E catabolites, but no increases in urinary vitamin K catabolites were found. Chapter 4 shows that α-T-injected rats increased biliary excretion of 5C-aglycone, a major vitamin K catabolite shared by MK-4 and PK. However, the overall in vivo excretion of vitamin K catabolites was not changed when urinary excretion was also taken into account. Aim 2 evaluated the hypothesis that α-T interferes with the conversion of PK to MK-4 because α-T and PK have similar side-chains. In Aim 2.1, conversion of PK or MN to MK-4 was tested in vivo. Rats were fed semi-purified diets containing equimolar concentrations of either PK or MN for 10 days, then α-T injections were undertaken. Chapter 3 shows that extra-hepatic tissues from α-T injected rats contained significantly lower MK-4 concentrations irrespective of whether the rats were fed PK or MN. These findings show that if vitamin E is interfering with the metabolic mechanism of MK-4 synthesis, then it is not specific to the cleavage of PK's side chain. In Aim 2.2, conversion of deuterium-labeled PK (d₄-PK) to d₄-MK-4 was used to evaluate the extra-hepatic tissue uptake of d₄-PK in α-T-injected rats. Rats were fed semi-purified diets containing equimolar concentrations of d₄-PK similar to my previous study for 10 days then α-T injections were undertaken for 7 days. Chapter 5 shows that total (labeled and unlabeled) vitamin K concentrations decreased in extra-hepatic tissues from α-T injected rats fed d₄-PK. Both d₄-MK-4 and d₄-PK concentrations decreased, suggesting that MK-4 concentrations were dependent upon those of d₄-PK. These findings suggest that PK, and not MN, is the primary substrate for MK-4 synthesis in extra-hepatic tissues. Moreover, both d₄-MK-4 and d₄-PK decreased in α-T-injected rats demonstrating that vitamin E's untoward effect on vitamin K status is likely a mechanism that is shared by both vitamin K forms and not specific to MK-4 synthesis. Recycling of vitamin K from the epoxide was not examined in this study and interference with the recycling mechanism for either PK or MK-4 in α-T injected rats has not been examined. Vitamin E metabolism is greatly increased in α-T-injected rats by increasing various xenobiotic pathways. Thus, vitamin K status was hypothesized to decrease in α-T-injected rats as a result of the up-regulation of these pathways. As shown in Aim 1, urinary vitamin K metabolite excretion was not increased in α-T-injected rats. In Aim 3.1, the biliary excretion of vitamins E and K were examined to evaluate whether the increased expression in biliary transporters, such as MDR1, led to increased vitamin K and E excretion via the bile. Chapter 4 shows that α-T increased in bile over the week of vitamin E injections and α-CEHC was the major vitamin E form excreted in bile. Although biliary PK secretion was unchanged and biliary MK-4 was undetectable, increased excretion of a major catabolite of both PK and MK-4, 5C-aglycone, was observed. In Aim, 3.2, the gene expression of enzymes and transporters in liver and extra-hepatic tissues as mechanisms involved in regulating their concentrations in these tissues was assessed. In Chapters 3 and 5, increased expression of biliary transporters were observed, one of which is known to bind the vitamin K intermediate MN as its substrate. It is possible other vitamin K catabolites, in addition to 5C-and 7C-aglycone, may have been excreted that were unaccounted for, e.g. MN or vitamin K epoxide metabolites. In summary, my studies have shown vitamin K status is decreased in α-T-injected rats because PK and MK-4 concentrations are decreased in many extra-hepatic tissues. Although metabolism of vitamin K was not stimulated in response to α-T injections, increased excretion of a vitamin K catabolite was measured in the bile; however it may not account for all of the vitamin K loss observed in tissues. Alternatively, transport of PK and MN to extra-hepatic tissues or MK-4 recycling may have been inhibited in response to vitamin E. Further studies are needed to distinguish between these mechanisms. Title: Vitamin E and K interactions : investigating mechanisms of reduced vitamin K status in response to excess vitamin E Author: Farley, Sherry Mae The primary goal of my studies was to elucidate the mechanisms for the well-recognized interaction between two nutrients, vitamins E and K. The outcomes from my studies assess mechanisms for adverse effects of vitamin E and provide novel information on mechanisms for vitamin K homeostasis. These findings will provide information relevant for assessing optimal intakes of vitamins E and K. This dissertation presents studies aimed at evaluating three different mechanisms by which vitamin K status could be decreased by increases in whole body vitamin E concentrations in rats supplemented with vitamin E by subcutaneous injections (100 mg α-tocopherol (α-T)/ kg body weight per day), the model system developed in the Traber lab. The tested mechanisms by which vitamin E leads to reduced vitamin K status were: 1) increasing vitamin K metabolism, 2) decreasing menaquinone-4 (MK-4) synthesis from dietary phylloquinone (PK) and 3) potentiating vitamin K excretion through xenobiotic pathways. Two approaches were undertaken to evaluate the hypothesis that vitamin E increases vitamin K metabolism. In Aim 1.1, the in vitro omega-hydroxylation of vitamin K by human cytochrome P450 CYP4F2 (expressed in insect microsomes) was tested because CYP4F2 is considered the limiting step in the catabolism of both vitamins. Chapter 2 shows that CYP4F2 more rapidly hydroxylated vitamin K compared with vitamin E. Moreover, vitamin E did not stimulate vitamin K metabolism in vitro. Thus, it is unlikely vitamin E stimulates vitamin K metabolism in vivo by direct interaction with the CYP4F2 enzyme-substrate complex. In Aim 1.2, the in vivo urinary and biliary excretion of vitamin K metabolites was investigated. Chapter 3 shows that α-T-injected rats significantly increased urinary excretion of vitamin E catabolites, but no increases in urinary vitamin K catabolites were found. Chapter 4 shows that α-T-injected rats increased biliary excretion of 5C-aglycone, a major vitamin K catabolite shared by MK-4 and PK. However, the overall in vivo excretion of vitamin K catabolites was not changed when urinary excretion was also taken into account. Aim 2 evaluated the hypothesis that α-T interferes with the conversion of PK to MK-4 because α-T and PK have similar side-chains. In Aim 2.1, conversion of PK or MN to MK-4 was tested in vivo. Rats were fed semi-purified diets containing equimolar concentrations of either PK or MN for 10 days, then α-T injections were undertaken. Chapter 3 shows that extra-hepatic tissues from α-T injected rats contained significantly lower MK-4 concentrations irrespective of whether the rats were fed PK or MN. These findings show that if vitamin E is interfering with the metabolic mechanism of MK-4 synthesis, then it is not specific to the cleavage of PK's side chain. In Aim 2.2, conversion of deuterium-labeled PK (d₄-PK) to d₄-MK-4 was used to evaluate the extra-hepatic tissue uptake of d₄-PK in α-T-injected rats. Rats were fed semi-purified diets containing equimolar concentrations of d₄-PK similar to my previous study for 10 days then α-T injections were undertaken for 7 days. Chapter 5 shows that total (labeled and unlabeled) vitamin K concentrations decreased in extra-hepatic tissues from α-T injected rats fed d₄-PK. Both d₄-MK-4 and d₄-PK concentrations decreased, suggesting that MK-4 concentrations were dependent upon those of d₄-PK. These findings suggest that PK, and not MN, is the primary substrate for MK-4 synthesis in extra-hepatic tissues. Moreover, both d₄-MK-4 and d₄-PK decreased in α-T-injected rats demonstrating that vitamin E's untoward effect on vitamin K status is likely a mechanism that is shared by both vitamin K forms and not specific to MK-4 synthesis. Recycling of vitamin K from the epoxide was not examined in this study and interference with the recycling mechanism for either PK or MK-4 in α-T injected rats has not been examined. Vitamin E metabolism is greatly increased in α-T-injected rats by increasing various xenobiotic pathways. Thus, vitamin K status was hypothesized to decrease in α-T-injected rats as a result of the up-regulation of these pathways. As shown in Aim 1, urinary vitamin K metabolite excretion was not increased in α-T-injected rats. In Aim 3.1, the biliary excretion of vitamins E and K were examined to evaluate whether the increased expression in biliary transporters, such as MDR1, led to increased vitamin K and E excretion via the bile. Chapter 4 shows that α-T increased in bile over the week of vitamin E injections and α-CEHC was the major vitamin E form excreted in bile. Although biliary PK secretion was unchanged and biliary MK-4 was undetectable, increased excretion of a major catabolite of both PK and MK-4, 5C-aglycone, was observed. In Aim, 3.2, the gene expression of enzymes and transporters in liver and extra-hepatic tissues as mechanisms involved in regulating their concentrations in these tissues was assessed. In Chapters 3 and 5, increased expression of biliary transporters were observed, one of which is known to bind the vitamin K intermediate MN as its substrate. It is possible other vitamin K catabolites, in addition to 5C-and 7C-aglycone, may have been excreted that were unaccounted for, e.g. MN or vitamin K epoxide metabolites. In summary, my studies have shown vitamin K status is decreased in α-T-injected rats because PK and MK-4 concentrations are decreased in many extra-hepatic tissues. Although metabolism of vitamin K was not stimulated in response to α-T injections, increased excretion of a vitamin K catabolite was measured in the bile; however it may not account for all of the vitamin K loss observed in tissues. Alternatively, transport of PK and MN to extra-hepatic tissues or MK-4 recycling may have been inhibited in response to vitamin E. Further studies are needed to distinguish between these mechanisms. Close

• 12292. [Article] Development of antioxidant dietary fibers from wine grape pomace and their applications as functional food ingredients

  Wine grape pomace (WGP), the byproduct from winemaking, is a good source of polyphenols and dietary fibers, and may be utilized as antioxidant dietary fibers (ADF) for food applications. The objectives ...

  Citation × Citation Citation Abstract Copy Title: Development of antioxidant dietary fibers from wine grape pomace and their applications as functional food ingredients Author: Tseng, Angela Y. Wine grape pomace (WGP), the byproduct from winemaking, is a good source of polyphenols and dietary fibers, and may be utilized as antioxidant dietary fibers (ADF) for food applications. The objectives of this thesis research were to first determine the phenolic compounds, antioxidant and antimicrobial activities in red WGP under different drying processes for long-term storage, and to further evaluate the feasibility of using WGP as a functional food ingredient in yogurt and salad dressing for enhancing the nutritional value and improving storability of the products. Two types of WGP samples, pomace containing seeds and skins (P) and pomace with skins only (S) from Pinot Noir (PN) and Merlot (M) were studied. Samples were subjected to four different drying conditions: 40 °C conventional and vacuum oven, 25 °C ambient air and freeze dry. Total phenolic content (TPC, by Folin-Ciocalteu assay), anthocyanins (ACY, by pH differential method) and flavanols content (TFC, by vanillin assay) of the samples along with their antioxidant activity (DPPH radical scavenge method, RSA) and antibacterial activity (minimum inhibition concentration, MIC) were determined during 16 weeks of storage under vacuum condition at 15±2 °C. Meanwhile, dietary fiber profile was evaluated by using gravimetric-enzyme method. Results showed that dietary fiber contents of PN-P, PN-S, M-P and M-S were 57-63% d.m. with the majority of insoluble fraction. Freeze dried WGP retained the highest bioactive compounds with TPC 21.19-67.74 mg GAE/g d.m., ACY of 0.35-0.76 mg Mal-3-glu/g d.m., TFC of 30.16-106.61 mg CE/g d.m. and RSA of 22.01-37.46 mg AAE/g d.m., followed with ambient air dried samples. Overall, TPC, TFC and RSA were higher in PN than in M, and higher in pomace than in skins, while reverse results were observed in ACY. All samples lost significant amount of bioactive compounds during storage, in which ambient air and freeze dried samples had TPC reduction of 32-56% and 35-58%, respectively at the end of 16 weeks of storage. RSA in PN-P and M-P remained more than 50 mg TE/g d.m., meaning WGP still met the criteria of ADF definition after 16 weeks of storage. WGP extracts showed higher antibacterial efficiency against L. innocua than that of E. coli with MIC of 2, 7, 3 and 8% against L. innocua, and 3, 6, 4 and 9% against E. coli for PN-P, PN-S, M-P and M-S samples, respectively. This study demonstrated that Pinot Noir and Merlot pomace are good sources of ADF even after 16 weeks of storage at 15 °C and vacuum condition. Due to the highest antioxidant activity (RSA 37.46 mg AAE/g) and dietary fiber content (61%), PN-P was selected as ADF to be fortified in yogurt and salad dressing. Three types of WGP: whole powder (WP), liquid extract (LE) and freeze dried extract (FDE) with different concentrations were incorporated into yogurt (Y), Italian (I) and Thousand Island (T) salad dressings. TPC, RSA and dietary fiber content, major quality attributes including pH and peroxide value (PV) during the shelf life and consumer acceptance of fortified products were evaluated. The highest ADF were obtained in 3% WP-Y, 1% WP-I and 2% WP-T samples with the dietary fiber contents of 1.98%, 2.12% and 1.83% and RSA of 935.78, 585.60 and 706.67 mg AAE/kg, respectively. WP fortified products had more dietary fiber content than that of LE and FDE fortified ones because of the insoluble fractions. The pH dropped from 4.52 to 4.32 for 3% WP-Y during three weeks of storage at 4 °C, but remained stable in WGP-I and WGP-T samples after four weeks of storage at 4 °C. Adding WGP resulted in 35-65% reduction of PV in all samples compared to the control. In WGP-Y, the viscosity increased, but syneresis and lactic acid percentage were stable during storage. The 1%WP-Y, 0.5%WP-I and 1%WP-T samples were mostly liked by consumers. Study demonstrated that WGP can be used as a functional food ingredient for enhancing nutraceutical content and extending shelf-life of the food products. This study provided important information about the economically feasible drying methods for retaining the bioactive compounds in WGP during processing and storage and also suggested that WGP can be utilized as antioxidant dietary fiber to be fortified in consumer products to promote nutritional benefit and extend product shelf-life. Title: Development of antioxidant dietary fibers from wine grape pomace and their applications as functional food ingredients Author: Tseng, Angela Y. Wine grape pomace (WGP), the byproduct from winemaking, is a good source of polyphenols and dietary fibers, and may be utilized as antioxidant dietary fibers (ADF) for food applications. The objectives of this thesis research were to first determine the phenolic compounds, antioxidant and antimicrobial activities in red WGP under different drying processes for long-term storage, and to further evaluate the feasibility of using WGP as a functional food ingredient in yogurt and salad dressing for enhancing the nutritional value and improving storability of the products. Two types of WGP samples, pomace containing seeds and skins (P) and pomace with skins only (S) from Pinot Noir (PN) and Merlot (M) were studied. Samples were subjected to four different drying conditions: 40 °C conventional and vacuum oven, 25 °C ambient air and freeze dry. Total phenolic content (TPC, by Folin-Ciocalteu assay), anthocyanins (ACY, by pH differential method) and flavanols content (TFC, by vanillin assay) of the samples along with their antioxidant activity (DPPH radical scavenge method, RSA) and antibacterial activity (minimum inhibition concentration, MIC) were determined during 16 weeks of storage under vacuum condition at 15±2 °C. Meanwhile, dietary fiber profile was evaluated by using gravimetric-enzyme method. Results showed that dietary fiber contents of PN-P, PN-S, M-P and M-S were 57-63% d.m. with the majority of insoluble fraction. Freeze dried WGP retained the highest bioactive compounds with TPC 21.19-67.74 mg GAE/g d.m., ACY of 0.35-0.76 mg Mal-3-glu/g d.m., TFC of 30.16-106.61 mg CE/g d.m. and RSA of 22.01-37.46 mg AAE/g d.m., followed with ambient air dried samples. Overall, TPC, TFC and RSA were higher in PN than in M, and higher in pomace than in skins, while reverse results were observed in ACY. All samples lost significant amount of bioactive compounds during storage, in which ambient air and freeze dried samples had TPC reduction of 32-56% and 35-58%, respectively at the end of 16 weeks of storage. RSA in PN-P and M-P remained more than 50 mg TE/g d.m., meaning WGP still met the criteria of ADF definition after 16 weeks of storage. WGP extracts showed higher antibacterial efficiency against L. innocua than that of E. coli with MIC of 2, 7, 3 and 8% against L. innocua, and 3, 6, 4 and 9% against E. coli for PN-P, PN-S, M-P and M-S samples, respectively. This study demonstrated that Pinot Noir and Merlot pomace are good sources of ADF even after 16 weeks of storage at 15 °C and vacuum condition. Due to the highest antioxidant activity (RSA 37.46 mg AAE/g) and dietary fiber content (61%), PN-P was selected as ADF to be fortified in yogurt and salad dressing. Three types of WGP: whole powder (WP), liquid extract (LE) and freeze dried extract (FDE) with different concentrations were incorporated into yogurt (Y), Italian (I) and Thousand Island (T) salad dressings. TPC, RSA and dietary fiber content, major quality attributes including pH and peroxide value (PV) during the shelf life and consumer acceptance of fortified products were evaluated. The highest ADF were obtained in 3% WP-Y, 1% WP-I and 2% WP-T samples with the dietary fiber contents of 1.98%, 2.12% and 1.83% and RSA of 935.78, 585.60 and 706.67 mg AAE/kg, respectively. WP fortified products had more dietary fiber content than that of LE and FDE fortified ones because of the insoluble fractions. The pH dropped from 4.52 to 4.32 for 3% WP-Y during three weeks of storage at 4 °C, but remained stable in WGP-I and WGP-T samples after four weeks of storage at 4 °C. Adding WGP resulted in 35-65% reduction of PV in all samples compared to the control. In WGP-Y, the viscosity increased, but syneresis and lactic acid percentage were stable during storage. The 1%WP-Y, 0.5%WP-I and 1%WP-T samples were mostly liked by consumers. Study demonstrated that WGP can be used as a functional food ingredient for enhancing nutraceutical content and extending shelf-life of the food products. This study provided important information about the economically feasible drying methods for retaining the bioactive compounds in WGP during processing and storage and also suggested that WGP can be utilized as antioxidant dietary fiber to be fortified in consumer products to promote nutritional benefit and extend product shelf-life. Close

• 12293. [Article] Grape and Wine Aroma Influenced by Vine Nutrient Status, Vigor and Crop Levels in Oregon Pinot Noir

  Wine volatile composition is one of the most important constitutes of wine quality, and it is greatly influenced by number of factors. The studies herein were conducted to evaluate the grape and wine aroma ...

  Citation × Citation Citation Abstract Copy Title: Grape and Wine Aroma Influenced by Vine Nutrient Status, Vigor and Crop Levels in Oregon Pinot Noir Author: Yuan, Fang Wine volatile composition is one of the most important constitutes of wine quality, and it is greatly influenced by number of factors. The studies herein were conducted to evaluate the grape and wine aroma affected by different vine nutrient status, vigor and crop levels of Oregon Pinot noir. In the first study, aroma potentials in early and late maturity Pinot noir grapes were investigated in two consecutive vintages. The grape samples were hydrolyzed under acidic conditions and the released odorants were studied by aroma extract dilution analysis (AEDA). Forty-nine main odor-active compounds were detected in the AEDA. The odorants released with high flavor dilution values were 1-hexanal, β-damascenone, guaiacol and vanillin, together with C₆ aldehydes and alcohols, 4-vinylguaiacol, 4-vinylphenol and 1-octen-3-one. The concentrations of aroma-active compounds were further quantitated by SPME-GC-MS and SBSE-GC-MS. Comparing with early harvest grapes, late harvest grapes released more β-damascenone, vanillin, 4-vinylguaiacol and 4-vinylphenol in both years according to both AEDA and quantitation results, suggesting they were important aroma compounds that contribute to the characteristic of mature Pinot noir grapes. The second study evaluated the volatile composition of grape berries subjected to varying levels of nitrogen (N), phosphorous (P) and potassium (K) supply. Pinot noir grapevines were grown in a pot-in-pot system for three years (beginning when they were 4-years-old) and fertigated with either complete nutrition (Control) or with reduced levels of either N, P, or K supply while holding all other nutrients constant. Nitrogen was varied from 7.50 mM total N supply (Control) to 1.13 mM in five discreet treatments, while P and K supply were each varied in four discreet treatments with the lowest rate of 0 mM during fertigation events. Aroma volatiles in berries were determined in each year using SPME-GC-MS technique. Results showed that reducing N supply resulted in lower concentrations of C₆ compounds and total β-damascenone in berries across all three years. Low N supply had little impact on monoterpenes. Reducing N supply resulted in higher bound form α-terpineol in two of the three years. Compared to P and K, N supply showed a more profound influence on the volatile profiles of the grape berries, indicating the important role of N in the biosynthesis of berry volatile and volatile precursors. The volatile composition of resulting wines from the same study was also investigated. Results showed that reducing N supply increased the total phenolic content in wine across all years. N supply has a profound impact on wine volatiles with the greatest effect on yeast-derived esters and higher alcohols. In general, reducing N supply decreased straight-chain esters and many straight chain alcohols, but increased the branched-chain esters, and phenethyl ester and phenethyl alcohol in wine across all years. The effect of N supply on monoterpenes in wine was not consistent from year to year. Low N wines also had reduced levels of volatile sulfur compounds in 2 of 3 years. Compared to the Control, reducing N and K supply resulted in lower quantities of total β-damascenone across all years. Altering P supply did not have reproducible effects on wine volatiles from year to year. The third study investigated the composition of Pinot noir wines produced from vines with varying vegetative vigor levels and two crop levels over three vintages (2011, 2012, and 2013) in the cool climate viticulture region of western Oregon. Wine was produced from grapes grown with two inter-row floor management treatments (tilled or grass) and two crop levels, including full crop and half crop achieved through cluster thinning. Crop thinning treatments didn’t alter the wine volatile composition. Certain wine volatiles were affected by the vineyard floor management treatments. Wines produced from grapes grown in the Grass treatment (lower vigor) had higher levels of grape-derived compounds such as α-terpineol, β-citronellol, vitispirane and TDN compared to wines produced from the Tilled treatment. Wines from Grass treatment also had higher isoamyl alcohol, phenethyl alcohol, isoamyl acetate, ethyl isobutyrate, ethyl isovalerate, and phenethyl acetate but lower levels of linalool, 1-propanol and 1-octanol. A subproject of this study investigated the carotenoid breakdown and C₁₃-norisoprenoids synthesis in Pinot noir grapes from vines of differing vigor and crop levels (yield). Carotenoid degradation and C₁₃-norisoprenoid synthesis during berry development with different vine balance was monitored from véraison to harvest in year 2013. Our data suggests that vineyard floor management had a greater influence than did cluster thinning on carotenoids composition in grapes. Grape berries from Tilled treatment vines have higher carotenoids and C₁₃-norisoprenoids than the grapes from Grass treatment vines. Multivariance analyses also showed some interactions between the vineyard floor treatments and cluster thinning treatments on the composition of carotenoids and C₁₃-norisoprenoids. Title: Grape and Wine Aroma Influenced by Vine Nutrient Status, Vigor and Crop Levels in Oregon Pinot Noir Author: Yuan, Fang Wine volatile composition is one of the most important constitutes of wine quality, and it is greatly influenced by number of factors. The studies herein were conducted to evaluate the grape and wine aroma affected by different vine nutrient status, vigor and crop levels of Oregon Pinot noir. In the first study, aroma potentials in early and late maturity Pinot noir grapes were investigated in two consecutive vintages. The grape samples were hydrolyzed under acidic conditions and the released odorants were studied by aroma extract dilution analysis (AEDA). Forty-nine main odor-active compounds were detected in the AEDA. The odorants released with high flavor dilution values were 1-hexanal, β-damascenone, guaiacol and vanillin, together with C₆ aldehydes and alcohols, 4-vinylguaiacol, 4-vinylphenol and 1-octen-3-one. The concentrations of aroma-active compounds were further quantitated by SPME-GC-MS and SBSE-GC-MS. Comparing with early harvest grapes, late harvest grapes released more β-damascenone, vanillin, 4-vinylguaiacol and 4-vinylphenol in both years according to both AEDA and quantitation results, suggesting they were important aroma compounds that contribute to the characteristic of mature Pinot noir grapes. The second study evaluated the volatile composition of grape berries subjected to varying levels of nitrogen (N), phosphorous (P) and potassium (K) supply. Pinot noir grapevines were grown in a pot-in-pot system for three years (beginning when they were 4-years-old) and fertigated with either complete nutrition (Control) or with reduced levels of either N, P, or K supply while holding all other nutrients constant. Nitrogen was varied from 7.50 mM total N supply (Control) to 1.13 mM in five discreet treatments, while P and K supply were each varied in four discreet treatments with the lowest rate of 0 mM during fertigation events. Aroma volatiles in berries were determined in each year using SPME-GC-MS technique. Results showed that reducing N supply resulted in lower concentrations of C₆ compounds and total β-damascenone in berries across all three years. Low N supply had little impact on monoterpenes. Reducing N supply resulted in higher bound form α-terpineol in two of the three years. Compared to P and K, N supply showed a more profound influence on the volatile profiles of the grape berries, indicating the important role of N in the biosynthesis of berry volatile and volatile precursors. The volatile composition of resulting wines from the same study was also investigated. Results showed that reducing N supply increased the total phenolic content in wine across all years. N supply has a profound impact on wine volatiles with the greatest effect on yeast-derived esters and higher alcohols. In general, reducing N supply decreased straight-chain esters and many straight chain alcohols, but increased the branched-chain esters, and phenethyl ester and phenethyl alcohol in wine across all years. The effect of N supply on monoterpenes in wine was not consistent from year to year. Low N wines also had reduced levels of volatile sulfur compounds in 2 of 3 years. Compared to the Control, reducing N and K supply resulted in lower quantities of total β-damascenone across all years. Altering P supply did not have reproducible effects on wine volatiles from year to year. The third study investigated the composition of Pinot noir wines produced from vines with varying vegetative vigor levels and two crop levels over three vintages (2011, 2012, and 2013) in the cool climate viticulture region of western Oregon. Wine was produced from grapes grown with two inter-row floor management treatments (tilled or grass) and two crop levels, including full crop and half crop achieved through cluster thinning. Crop thinning treatments didn’t alter the wine volatile composition. Certain wine volatiles were affected by the vineyard floor management treatments. Wines produced from grapes grown in the Grass treatment (lower vigor) had higher levels of grape-derived compounds such as α-terpineol, β-citronellol, vitispirane and TDN compared to wines produced from the Tilled treatment. Wines from Grass treatment also had higher isoamyl alcohol, phenethyl alcohol, isoamyl acetate, ethyl isobutyrate, ethyl isovalerate, and phenethyl acetate but lower levels of linalool, 1-propanol and 1-octanol. A subproject of this study investigated the carotenoid breakdown and C₁₃-norisoprenoids synthesis in Pinot noir grapes from vines of differing vigor and crop levels (yield). Carotenoid degradation and C₁₃-norisoprenoid synthesis during berry development with different vine balance was monitored from véraison to harvest in year 2013. Our data suggests that vineyard floor management had a greater influence than did cluster thinning on carotenoids composition in grapes. Grape berries from Tilled treatment vines have higher carotenoids and C₁₃-norisoprenoids than the grapes from Grass treatment vines. Multivariance analyses also showed some interactions between the vineyard floor treatments and cluster thinning treatments on the composition of carotenoids and C₁₃-norisoprenoids. Close

• 12294. [Article] Understanding Public Perceptions of Post-Wildfire Landscape Recovery

  Forest disturbances, such as wildfires, pine beetle outbreaks, and floods are important features of many landscapes and ecosystems. Many disturbances are increasing in size, frequency, and intensity due ...

  Citation × Citation Citation Abstract Copy Title: Understanding Public Perceptions of Post-Wildfire Landscape Recovery Author: Kooistra, Chad Forest disturbances, such as wildfires, pine beetle outbreaks, and floods are important features of many landscapes and ecosystems. Many disturbances are increasing in size, frequency, and intensity due to changing climates and land management decisions. The changing ecological and aesthetic conditions following a disturbance can lead to negative short- and long-term social impacts. This dissertation research examines one aspect of the relationship between people and their environment in the context of forest disturbances and landscape changes. Specifically, it explores how people perceive a changing landscape after a forest disturbance, a trajectory referred to here as landscape recovery. After describing the larger context of forest disturbances in the introductory chapter, with a focus on wildfires, my second dissertation chapter developed a conceptual framework for understanding how people perceive post-disturbance landscape recovery. It examined the social factors that are most likely to influence those perceptions based on literature from various disciplines. These factors included visual cues and aesthetic preferences, landscape values and connections, and beliefs about the ecological role of disturbances. I described how the concepts and methodological approaches from mental models and social representations traditions help depict and explain how perceptions of landscape recovery can be studied in a way that explores the process shaping the perceptions. I explained how these perceptions likely exist along a spectrum from more simple perceptions focused on aesthetic judgments to more complex perceptions based more on ecological knowledge. I then proposed a research agenda to further investigate this framework, along with a summary of management considerations. The third chapter empirically explored the framework from the previous chapter by applying social representations theory (SRT) to qualitative research in Montana about how people perceive post-wildfire landscape recovery. I examined the mechanistic (i.e., anchoring and objectification) and structural (i.e., central core and peripheral elements) aspects of representations by integrating the factors proposed earlier as most influential in affecting perceptions of recovery. Interviews were conducted in 2014 with 30 residents who experienced the 2012 Dahl Fire, near Roundup, MT. Participants were purposively selected to represent a range of the factors described in Chapter 2. The main propositions from Chapter 2 were explored in the data collection and analysis steps. The core of all respondents' representations was centered on the concept of "Mother Nature." The factors identified in Chapter 2 further shaped representations uniquely across the two main groups of residents (rural lifestyle and working landscape residents) through the anchoring and objectification processes. People's representations about recovery were anchored in general beliefs about the past ecological and socio-cultural role of fire in the landscape as influenced by their past experiences and knowledge about ecological disturbances. Interpretations of different aspects of the landscape, including vegetation composition and key ecosystem functions, were filtered through people's values for the landscape and their specific beliefs about how the fire affected the landscape. This led to variation in specific notions of what constitutes a recovered landscape across the two main social groups there. These findings are discussed in the context of SRT and post-wildfire management. My fourth chapter took a broader look at the variables that influence perceptions of landscape recovery across different wildfires. Twenty-five fires that occurred in 2011 or 2012 in WA, OR, MT, and ID were selected to represent a range of fire behavior characteristics and landscape impacts. Then, residents who live near each of the 25 fires were randomly selected to receive survey questionnaires which asked about multiple facets of their experiences with the fire, the perceived social impacts from the fire, and specifically how the landscape had changed/recovered since the fire. Results showed that, overall, perceptions of landscape recovery no more than two years after the fire were positive. Regression analysis suggested that perceptions of recovery can be explained fairly well with several key variables. More negative evaluations of recovery were related to negative impacts to people's attachment to the landscape, negative perceptions of erosion problems, and longer lasting fires. More positive evaluations of recovery were related to more positive beliefs about the beneficial role of fire in terms of landscape health. Hierarchical Linear Modelling (HLM) analysis showed that these relationships were mostly consistent across fires, though there was some variability in the relationships between perceptions of landscape recovery and the variables that measured perceptions of erosion and beliefs about the ecological role of fire. These findings are discussed in terms of the scope of the study as well as their management implications. My fifth and concluding chapter summarized the main findings from each chapter and integrated them into a larger social-ecological context. Key limitations, considerations related to the validity and reliability of my research, and future research needs are discussed. My dissertation furthers the conceptual and empirical understanding of how people perceive landscape changes from natural disturbances and how managers can include these social dimensions into future planning and implementation efforts. Title: Understanding Public Perceptions of Post-Wildfire Landscape Recovery Author: Kooistra, Chad Forest disturbances, such as wildfires, pine beetle outbreaks, and floods are important features of many landscapes and ecosystems. Many disturbances are increasing in size, frequency, and intensity due to changing climates and land management decisions. The changing ecological and aesthetic conditions following a disturbance can lead to negative short- and long-term social impacts. This dissertation research examines one aspect of the relationship between people and their environment in the context of forest disturbances and landscape changes. Specifically, it explores how people perceive a changing landscape after a forest disturbance, a trajectory referred to here as landscape recovery. After describing the larger context of forest disturbances in the introductory chapter, with a focus on wildfires, my second dissertation chapter developed a conceptual framework for understanding how people perceive post-disturbance landscape recovery. It examined the social factors that are most likely to influence those perceptions based on literature from various disciplines. These factors included visual cues and aesthetic preferences, landscape values and connections, and beliefs about the ecological role of disturbances. I described how the concepts and methodological approaches from mental models and social representations traditions help depict and explain how perceptions of landscape recovery can be studied in a way that explores the process shaping the perceptions. I explained how these perceptions likely exist along a spectrum from more simple perceptions focused on aesthetic judgments to more complex perceptions based more on ecological knowledge. I then proposed a research agenda to further investigate this framework, along with a summary of management considerations. The third chapter empirically explored the framework from the previous chapter by applying social representations theory (SRT) to qualitative research in Montana about how people perceive post-wildfire landscape recovery. I examined the mechanistic (i.e., anchoring and objectification) and structural (i.e., central core and peripheral elements) aspects of representations by integrating the factors proposed earlier as most influential in affecting perceptions of recovery. Interviews were conducted in 2014 with 30 residents who experienced the 2012 Dahl Fire, near Roundup, MT. Participants were purposively selected to represent a range of the factors described in Chapter 2. The main propositions from Chapter 2 were explored in the data collection and analysis steps. The core of all respondents' representations was centered on the concept of "Mother Nature." The factors identified in Chapter 2 further shaped representations uniquely across the two main groups of residents (rural lifestyle and working landscape residents) through the anchoring and objectification processes. People's representations about recovery were anchored in general beliefs about the past ecological and socio-cultural role of fire in the landscape as influenced by their past experiences and knowledge about ecological disturbances. Interpretations of different aspects of the landscape, including vegetation composition and key ecosystem functions, were filtered through people's values for the landscape and their specific beliefs about how the fire affected the landscape. This led to variation in specific notions of what constitutes a recovered landscape across the two main social groups there. These findings are discussed in the context of SRT and post-wildfire management. My fourth chapter took a broader look at the variables that influence perceptions of landscape recovery across different wildfires. Twenty-five fires that occurred in 2011 or 2012 in WA, OR, MT, and ID were selected to represent a range of fire behavior characteristics and landscape impacts. Then, residents who live near each of the 25 fires were randomly selected to receive survey questionnaires which asked about multiple facets of their experiences with the fire, the perceived social impacts from the fire, and specifically how the landscape had changed/recovered since the fire. Results showed that, overall, perceptions of landscape recovery no more than two years after the fire were positive. Regression analysis suggested that perceptions of recovery can be explained fairly well with several key variables. More negative evaluations of recovery were related to negative impacts to people's attachment to the landscape, negative perceptions of erosion problems, and longer lasting fires. More positive evaluations of recovery were related to more positive beliefs about the beneficial role of fire in terms of landscape health. Hierarchical Linear Modelling (HLM) analysis showed that these relationships were mostly consistent across fires, though there was some variability in the relationships between perceptions of landscape recovery and the variables that measured perceptions of erosion and beliefs about the ecological role of fire. These findings are discussed in terms of the scope of the study as well as their management implications. My fifth and concluding chapter summarized the main findings from each chapter and integrated them into a larger social-ecological context. Key limitations, considerations related to the validity and reliability of my research, and future research needs are discussed. My dissertation furthers the conceptual and empirical understanding of how people perceive landscape changes from natural disturbances and how managers can include these social dimensions into future planning and implementation efforts. Close

• 12295. [Article] Patterns of crown damage within a large wildfire in the Klamath-Siskiyou bioregion

  The 2002 Biscuit Fire burned through more than 200,000 ha of mixed conifer/ evergreen hardwood forests in southwestern Oregon and northwestern California. The remarkable size of the fire and the diversity ...

  Citation × Citation Citation Abstract Copy Title: Patterns of crown damage within a large wildfire in the Klamath-Siskiyou bioregion Author: Thompson, Jonathan R. The 2002 Biscuit Fire burned through more than 200,000 ha of mixed conifer/ evergreen hardwood forests in southwestern Oregon and northwestern California. The remarkable size of the fire and the diversity of conditions through which it burned provided an opportunity to analyze the correlates of burn severity across vegetation types and disturbance histories and to describe the weather, topographical, and fuel conditions that gave rise to the mosaic of crown damage. In chapter two, I focused on a region that had burned previously by the 1987 Silver Fire then was subject, in part, to salvage-logging and conifer planting before being reburned by the Biscuit Fire. I used the Landsat-based differenced normalized burn ratio (dNBR) to quantify severity in both fires and took a hypothesis-testing approach to answering two questions: First, was severity in the Biscuit Fire associated with severity in the Silver Fire in unmanaged areas? And second, did areas that were salvaged-logged and planted with conifers after the Silver Fire burn more or less severely in the Biscuit Fire than comparable unmanaged areas? I found that areas that burned severely in 1987 tended to re-burn at high severity in 2002, after controlling for the influence of several topographical and biophysical covariates. Areas unaffected by the initial fire tended to burn at the lowest severities in 2002. In addition, areas that were salvage-logged and planted after the initial fire burned more severely than comparable unmanaged areas, suggesting that post-fire logging and planting did not reduce future fire severity as had been suggested by some. In chapter three, I again focused on the twice-burned landscape, but this time I used a temporal sequence of digital aerial photography plots (6.25 ha) to measure changes in shrub-stratum, hardwood, and conifer cover. I estimated the strength and nature of relationships between crown damage and several fuel, topographical, weather, and management variables. Median crown damage, including damage to the shrub-stratum, on unmanaged plots was 63% after the Biscuit Fire and was most strongly related to damage in the Silver Fire. Plots that burned severely in the Silver Fire and had succeeded to a mix of shrubs and tree regeneration experienced high levels of Biscuit Fire damage. Plots dominated by large conifer cover after the Silver Fire had the lowest levels of Biscuit Fire canopy damage. Median crown damage was 39% for conifer cover and 85% for hardwood cover, and was most strongly related to daily average temperature and "burn period," an index of fire weather and fire suppression effort. Damage in the tree-stratum was largely independent of Silver Fire severity. Plots that had experienced stand replacing fire in 1987 and then were logged and planted with conifers had median crown damage of 100%. Plots that experienced a stand replacing fire but were unmanaged had median crown damage of 95%. The managed areas were at higher topographical positions and had greater total pre-fire cover, which may explain the small difference. These results suggest that in productive, fire-prone landscapes, the patch mosaic of young regenerating forest created by mixed-severity fire can structure the severity pattern of future wildfires occurring at short intervals and support the previous studies findings that post-fire logging and planting did not reduce fire severity. In Chapter four, I expanded my focus to include the entire region burned by the Biscuit Fire and again used digital aerial photos taken before and after the fire to interpret patterns of crown damage and relate them to several fuel, topographical, weather, and management variables. Ninety-eight percent of plots experienced some level of crown damage, but only 10% experienced complete crown damage. The median level of crown damage on unmanaged plots was 74%. Median conifer damage was 52%. The most important predictors of total crown damage were the percentage of pre-fire shrub-stratum vegetation cover and average daily temperature. The most important predictors of conifer damage were average daily temperature and burn period. Increasing levels of shrub-stratum cover were associated with increasing levels of conifer damage and hardwood damage. Large conifers had 32% median crown damage while small conifers had 62% median crown damage. Owing largely to widespread shrub-stratum cover, low-productivity ultramafic soils had 92% median crown damage compared to 59% on non-ultramafic sites. Patterns of damage were similar within the area that burned previously in the 1987 Silver Fire and edaphically comparable areas without a recently history of fire. Median crown damage in conifer plantations was 89% and plantation age was, by far, the most important predictor of the level of damage. Plantations under 20 years old experienced the highest rates of damage. I conclude that weather and vegetation conditions--not topography--were the primary determinants of Biscuit Fire crown damage. These findings suggest that in productive fire-prone ecosystems, fuel treatments that open tree canopies and stimulate shrub-stratum development may be counterproductive. Title: Patterns of crown damage within a large wildfire in the Klamath-Siskiyou bioregion Author: Thompson, Jonathan R. The 2002 Biscuit Fire burned through more than 200,000 ha of mixed conifer/ evergreen hardwood forests in southwestern Oregon and northwestern California. The remarkable size of the fire and the diversity of conditions through which it burned provided an opportunity to analyze the correlates of burn severity across vegetation types and disturbance histories and to describe the weather, topographical, and fuel conditions that gave rise to the mosaic of crown damage. In chapter two, I focused on a region that had burned previously by the 1987 Silver Fire then was subject, in part, to salvage-logging and conifer planting before being reburned by the Biscuit Fire. I used the Landsat-based differenced normalized burn ratio (dNBR) to quantify severity in both fires and took a hypothesis-testing approach to answering two questions: First, was severity in the Biscuit Fire associated with severity in the Silver Fire in unmanaged areas? And second, did areas that were salvaged-logged and planted with conifers after the Silver Fire burn more or less severely in the Biscuit Fire than comparable unmanaged areas? I found that areas that burned severely in 1987 tended to re-burn at high severity in 2002, after controlling for the influence of several topographical and biophysical covariates. Areas unaffected by the initial fire tended to burn at the lowest severities in 2002. In addition, areas that were salvage-logged and planted after the initial fire burned more severely than comparable unmanaged areas, suggesting that post-fire logging and planting did not reduce future fire severity as had been suggested by some. In chapter three, I again focused on the twice-burned landscape, but this time I used a temporal sequence of digital aerial photography plots (6.25 ha) to measure changes in shrub-stratum, hardwood, and conifer cover. I estimated the strength and nature of relationships between crown damage and several fuel, topographical, weather, and management variables. Median crown damage, including damage to the shrub-stratum, on unmanaged plots was 63% after the Biscuit Fire and was most strongly related to damage in the Silver Fire. Plots that burned severely in the Silver Fire and had succeeded to a mix of shrubs and tree regeneration experienced high levels of Biscuit Fire damage. Plots dominated by large conifer cover after the Silver Fire had the lowest levels of Biscuit Fire canopy damage. Median crown damage was 39% for conifer cover and 85% for hardwood cover, and was most strongly related to daily average temperature and "burn period," an index of fire weather and fire suppression effort. Damage in the tree-stratum was largely independent of Silver Fire severity. Plots that had experienced stand replacing fire in 1987 and then were logged and planted with conifers had median crown damage of 100%. Plots that experienced a stand replacing fire but were unmanaged had median crown damage of 95%. The managed areas were at higher topographical positions and had greater total pre-fire cover, which may explain the small difference. These results suggest that in productive, fire-prone landscapes, the patch mosaic of young regenerating forest created by mixed-severity fire can structure the severity pattern of future wildfires occurring at short intervals and support the previous studies findings that post-fire logging and planting did not reduce fire severity. In Chapter four, I expanded my focus to include the entire region burned by the Biscuit Fire and again used digital aerial photos taken before and after the fire to interpret patterns of crown damage and relate them to several fuel, topographical, weather, and management variables. Ninety-eight percent of plots experienced some level of crown damage, but only 10% experienced complete crown damage. The median level of crown damage on unmanaged plots was 74%. Median conifer damage was 52%. The most important predictors of total crown damage were the percentage of pre-fire shrub-stratum vegetation cover and average daily temperature. The most important predictors of conifer damage were average daily temperature and burn period. Increasing levels of shrub-stratum cover were associated with increasing levels of conifer damage and hardwood damage. Large conifers had 32% median crown damage while small conifers had 62% median crown damage. Owing largely to widespread shrub-stratum cover, low-productivity ultramafic soils had 92% median crown damage compared to 59% on non-ultramafic sites. Patterns of damage were similar within the area that burned previously in the 1987 Silver Fire and edaphically comparable areas without a recently history of fire. Median crown damage in conifer plantations was 89% and plantation age was, by far, the most important predictor of the level of damage. Plantations under 20 years old experienced the highest rates of damage. I conclude that weather and vegetation conditions--not topography--were the primary determinants of Biscuit Fire crown damage. These findings suggest that in productive fire-prone ecosystems, fuel treatments that open tree canopies and stimulate shrub-stratum development may be counterproductive. Close

• 12296. [Article] The oligocene and miocene geology of the Tillamook embayment Tillamook County, northwest Oregon

  Eleven sedimentary and volcanic rock units are mapped and described in the thesis area, and chronicle the dynamic geologic history of the Tillamook embayment from the Oligocene through the middle Mlocene. ...

  Citation × Citation Citation Abstract Copy Title: The oligocene and miocene geology of the Tillamook embayment Tillamook County, northwest Oregon Author: Parker, Michael J. (Michael John), 1958- Eleven sedimentary and volcanic rock units are mapped and described in the thesis area, and chronicle the dynamic geologic history of the Tillamook embayment from the Oligocene through the middle Mlocene. The oldest unit is the Zemorrian to early Saucesian Smuggler Cove formation, a bathyal tuffaceous mudstone with some thin- to thick-bedded tuff layers deposited on the middle to upper continental slope during a period of explosive silicic volcanism in the Western Cascade arc. Uppermost Smuggler Cove strata are coarser grained, grading upward to arkosic turbidite sandstone and mudstone and thick bloturbated silty sandstone deposited on the outer shelf during marine regression. This regression heralded the progradation of the overlying shallow-marine Bewley Creek formation (informal) depositional system. The Bewley Creek formation (informal) is proposed in this study for a sequence of pumiceous, volcaniclastic-rich lower Miocene feldspathic litharenites and lithic arkoses deposited during the Pillarlan-stage near the mouth of an ancestral Columbia River. The unit grades from bioturbated silty sandstone to fine-grained hummocky cross-stratified and coarser grained channelized sandstones deposited within, or peripheral to a wave-dominated delta or ebb tidal-delta channel complex. Progradatlon of the Bewley Creek formation may have been caused, in part, by increased volcaniclastic sedimentation attending a pulse of explosive volcanism in the adjacent Western Cascade arc. Reduced volcanic activity, possibly coupled with basin subsidence or eustatic sea level rise, resulted in deposition of mudstones of the Sutton Creek member (informal; proposed) of the Nye Mudstone. The Saucesian Sutton Creek member consists of bathyal, laminated, carbonaceous, and moderately tuffaceous mudstone deposited in an upper continental slope basin. The upper part of the unit contains common lithic to arkosic turbidite sandstone interbeds within nested channel-fill deposits. These strata represent a channelized shelf-slope break environment adjacent to the shallow-marine Angora Peak member of the Astoria Formation depositlonal system. Subsequent marine regression resulted in progradation of the Pillarian- to Newportian-stage arkosic-micaceous sandstone-rich Angora Peak member into the Tillamook embayment. Grainsize analysis, sandstone petrography, scanning electron microscopy, and heavy mineral analyses suggest these lower to middle Miocene mollusk-bearing, fine- to medium-grained sandstones were predominantly deposited near the mouth of an ancestral Columbia River. They accumulated on a high-energy Inner shelf within or down drift of a wave-dominated delta or ebb-tidal delta complex, evidenced by paleocurrent analyses, hummocky cross-stratification and trough cross-stratified submarine channel-fill sequences. The Angora Peak member disconformably overlies Zemorrian mudstones of the Smuggler Cove formation at Cape Kiwanda suggesting local uplift and erosion in that area, followed by Newportian stage transgression in the Tillamook embayment. Exotic cobbles and boulders of two mica granite and sedimentary quartzite at Cape Kiwanda were probably derived from the Idaho Batholith and Precambrian sandstone terrains in Montana, transported via an ancestral Columbia River and longshore current to the shelf possibly bound within tree root bundles. The Netarts Bay member (informal) of the Astoria Formation Is proposed In this study for a late Sauceslan package of fine-grained to pebbly amalgamated and interbedded turbidite, grainflow, and fluldized flow friable thick-bedded lithic arkoses. These massive sandstones contain large penecontemporaneously emplaced channel wall-blocks and naller slltstone rip-ups. These lower to middle Miocene strata were deposited in a submarine canyon head and channel complex offshore of the shallow-marine Angora Peak member depositlonal system. Netarts Bay strata cut Into the underlying Angora Peak shelf strata, and cut and Interfinger with bathyal slope mudstones of the Cannon Beach member of the Astoria Formation. The overlying lower Cannon Beach member Is composed of laminated bathyal mudstones with rare turbidite sandstone interbeds deposited in a coarse clastic-starved slope environment. Upper Cannon Beach member strata In the Tillamook area are characterized by micaceous arkosic and lithic arkosic turbidite sandstones that underlie and occur within nested channel-fill sequences. Bloturbated carbonaceous cross-bedded sandstone In the upper Cannon Beach member records shallowing of the Tillamook embayment to a channelized upper slope to shelf environment. The Tillamook embayment was uplifted and dissected prior to the arrival of six to ten Intracanyon subaerial and submarine lava flows of the Columbia River Basalt Group. These middle Miocene flows, delineatedon the basis of geochemical composition and magnetic polarity, Include (in stratigraphic order) the Grouse Creek (R2 low MgO-low T102), Winterwater (N2 low MgO-low Ti02), and Sentinel Bluffs (high MgO) units of the Grande Ronde Basalt, and the Ginkgo unit of the Frenchman Springs member of the Wanapum Basalt. Orientation of Grande Ponde Basalt foreset-bedded pillow palagonite complexes and lava delta sequences indicate that these Columbia River Basalt units flowed westward into the Tillainook embayment, possibly through a saddle in the ancestral Oregon Coast Range. Marine transgression and deposition of hummocky cross-stratified arkosic marine strata of the Sandstone of Whale Cove followed emplacement of the last Grande Ronde flows. This was succeeded by a regression, as Indicated by the overlying subaerial plagioclase-phyric Ginkgo Unit flow of the Frenchman Springs Basalt. Locally, Winterwater and Sentinel Bluffs unit basalt occur as brecciated peperitic sills and dikes. These were emplaced through the process of "auto-invasion" when dense lava injected downward Into semi-lithifled Tertiary strata under the influence of both a pressure head augmented by flashing steam, and steam blasting. The thesis area is crossed by a complex network of high-angle northwest- and northeast-tending normal and reverse faults, and both low and high-angle east-trending reverse and thrust faults. These faults may have developed through a north-south compressional tectonic regime, a dextral shear couple, or a combination of these two tectonic regimes. Many faults cut Columbia River Basalt units and are thus middle Miocene or younger in age. Tertiary strata including the Columbia River Basalts are also folded within a broad westward-plunging syncline which suggests a middle Miocene or younger compressional event. Source rock analyses indicate that the mudstones of the Cannon Beach member, Sutton Creek member, and Smuggler Cove formation contain type III kerogen capable of generating natural gas only. Although these rocks have thermally innature vitrinite reflectance values, they contain sufficiently high total organic carbon content to be considered potential lean source rocks. Arkosic sandstones of the Angora Peak and Netarts Bay members have fair to good reservoir rock characteristics, and may represent reservoirs offshore for matured hydrocarbons generated from deeply buried source rocks. Title: The oligocene and miocene geology of the Tillamook embayment Tillamook County, northwest Oregon Author: Parker, Michael J. (Michael John), 1958- Eleven sedimentary and volcanic rock units are mapped and described in the thesis area, and chronicle the dynamic geologic history of the Tillamook embayment from the Oligocene through the middle Mlocene. The oldest unit is the Zemorrian to early Saucesian Smuggler Cove formation, a bathyal tuffaceous mudstone with some thin- to thick-bedded tuff layers deposited on the middle to upper continental slope during a period of explosive silicic volcanism in the Western Cascade arc. Uppermost Smuggler Cove strata are coarser grained, grading upward to arkosic turbidite sandstone and mudstone and thick bloturbated silty sandstone deposited on the outer shelf during marine regression. This regression heralded the progradation of the overlying shallow-marine Bewley Creek formation (informal) depositional system. The Bewley Creek formation (informal) is proposed in this study for a sequence of pumiceous, volcaniclastic-rich lower Miocene feldspathic litharenites and lithic arkoses deposited during the Pillarlan-stage near the mouth of an ancestral Columbia River. The unit grades from bioturbated silty sandstone to fine-grained hummocky cross-stratified and coarser grained channelized sandstones deposited within, or peripheral to a wave-dominated delta or ebb tidal-delta channel complex. Progradatlon of the Bewley Creek formation may have been caused, in part, by increased volcaniclastic sedimentation attending a pulse of explosive volcanism in the adjacent Western Cascade arc. Reduced volcanic activity, possibly coupled with basin subsidence or eustatic sea level rise, resulted in deposition of mudstones of the Sutton Creek member (informal; proposed) of the Nye Mudstone. The Saucesian Sutton Creek member consists of bathyal, laminated, carbonaceous, and moderately tuffaceous mudstone deposited in an upper continental slope basin. The upper part of the unit contains common lithic to arkosic turbidite sandstone interbeds within nested channel-fill deposits. These strata represent a channelized shelf-slope break environment adjacent to the shallow-marine Angora Peak member of the Astoria Formation depositlonal system. Subsequent marine regression resulted in progradation of the Pillarian- to Newportian-stage arkosic-micaceous sandstone-rich Angora Peak member into the Tillamook embayment. Grainsize analysis, sandstone petrography, scanning electron microscopy, and heavy mineral analyses suggest these lower to middle Miocene mollusk-bearing, fine- to medium-grained sandstones were predominantly deposited near the mouth of an ancestral Columbia River. They accumulated on a high-energy Inner shelf within or down drift of a wave-dominated delta or ebb-tidal delta complex, evidenced by paleocurrent analyses, hummocky cross-stratification and trough cross-stratified submarine channel-fill sequences. The Angora Peak member disconformably overlies Zemorrian mudstones of the Smuggler Cove formation at Cape Kiwanda suggesting local uplift and erosion in that area, followed by Newportian stage transgression in the Tillamook embayment. Exotic cobbles and boulders of two mica granite and sedimentary quartzite at Cape Kiwanda were probably derived from the Idaho Batholith and Precambrian sandstone terrains in Montana, transported via an ancestral Columbia River and longshore current to the shelf possibly bound within tree root bundles. The Netarts Bay member (informal) of the Astoria Formation Is proposed In this study for a late Sauceslan package of fine-grained to pebbly amalgamated and interbedded turbidite, grainflow, and fluldized flow friable thick-bedded lithic arkoses. These massive sandstones contain large penecontemporaneously emplaced channel wall-blocks and naller slltstone rip-ups. These lower to middle Miocene strata were deposited in a submarine canyon head and channel complex offshore of the shallow-marine Angora Peak member depositlonal system. Netarts Bay strata cut Into the underlying Angora Peak shelf strata, and cut and Interfinger with bathyal slope mudstones of the Cannon Beach member of the Astoria Formation. The overlying lower Cannon Beach member Is composed of laminated bathyal mudstones with rare turbidite sandstone interbeds deposited in a coarse clastic-starved slope environment. Upper Cannon Beach member strata In the Tillamook area are characterized by micaceous arkosic and lithic arkosic turbidite sandstones that underlie and occur within nested channel-fill sequences. Bloturbated carbonaceous cross-bedded sandstone In the upper Cannon Beach member records shallowing of the Tillamook embayment to a channelized upper slope to shelf environment. The Tillamook embayment was uplifted and dissected prior to the arrival of six to ten Intracanyon subaerial and submarine lava flows of the Columbia River Basalt Group. These middle Miocene flows, delineatedon the basis of geochemical composition and magnetic polarity, Include (in stratigraphic order) the Grouse Creek (R2 low MgO-low T102), Winterwater (N2 low MgO-low Ti02), and Sentinel Bluffs (high MgO) units of the Grande Ronde Basalt, and the Ginkgo unit of the Frenchman Springs member of the Wanapum Basalt. Orientation of Grande Ponde Basalt foreset-bedded pillow palagonite complexes and lava delta sequences indicate that these Columbia River Basalt units flowed westward into the Tillainook embayment, possibly through a saddle in the ancestral Oregon Coast Range. Marine transgression and deposition of hummocky cross-stratified arkosic marine strata of the Sandstone of Whale Cove followed emplacement of the last Grande Ronde flows. This was succeeded by a regression, as Indicated by the overlying subaerial plagioclase-phyric Ginkgo Unit flow of the Frenchman Springs Basalt. Locally, Winterwater and Sentinel Bluffs unit basalt occur as brecciated peperitic sills and dikes. These were emplaced through the process of "auto-invasion" when dense lava injected downward Into semi-lithifled Tertiary strata under the influence of both a pressure head augmented by flashing steam, and steam blasting. The thesis area is crossed by a complex network of high-angle northwest- and northeast-tending normal and reverse faults, and both low and high-angle east-trending reverse and thrust faults. These faults may have developed through a north-south compressional tectonic regime, a dextral shear couple, or a combination of these two tectonic regimes. Many faults cut Columbia River Basalt units and are thus middle Miocene or younger in age. Tertiary strata including the Columbia River Basalts are also folded within a broad westward-plunging syncline which suggests a middle Miocene or younger compressional event. Source rock analyses indicate that the mudstones of the Cannon Beach member, Sutton Creek member, and Smuggler Cove formation contain type III kerogen capable of generating natural gas only. Although these rocks have thermally innature vitrinite reflectance values, they contain sufficiently high total organic carbon content to be considered potential lean source rocks. Arkosic sandstones of the Angora Peak and Netarts Bay members have fair to good reservoir rock characteristics, and may represent reservoirs offshore for matured hydrocarbons generated from deeply buried source rocks. Close

• 12297. [Article] Structure of the southern Mormon Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona

  Detailed geologic mapping in the Mormon Mountains and new geophysical data provide significant insight into contractional and extensional tectonics in southern Nevada, southwest Utah, and northwest Arizona. ...

  Citation × Citation Citation Abstract Copy Title: Structure of the southern Mormon Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona Author: Carpenter, James Anthony Detailed geologic mapping in the Mormon Mountains and new geophysical data provide significant insight into contractional and extensional tectonics in southern Nevada, southwest Utah, and northwest Arizona. The rocks in the region were complexly deformed during two distinct tectonic episodes. Numerous interrelated events occurred within each episode. The first tectonic episode, related to the Sevier orogeny, was characterized by east-west crustal shortening which culminated in thin-skinned decollement style folding and thrusting during the Cretaceous. The Virgin-Beaver Dam Mountains anticline, a Laramide-type basement-involved uplift, represents the only thick-skinned contractional structure in the region. The second tectonic episode, related to basin-range rifting, was characterized by east-west crustal extension which was accommodated by high-angle normal faults, with dips averaging 60 degrees, in the brittle upper crust. In this area, basin-range rifting initiated in the Oligocene and continued to Recent time. Relations in the North Muddy Mountains in southern Nevada suggest that the Muddy Mountain thrust sheet advanced and overrode the Weiser syncline during the Cenomanian and may have continued to advance in Turonian time. In the southern Mormon Mountains, the Cambrian Bonanza King Formation lies in the hanging wall flat position in thrust contact with the overturned Petrified Forest Member of the Triassic Chinle Formation at the footwall ramp. The thrust sheet advanced eastward more than 30 km from the place of origin. Thrust imbrication, and probably the formation of hanging wall horses, likely occurred as the Muddy Mountain thrust sheet encountered and ascended up the footwall ramp zone (composed largely of competent carbonate rocks) where slices of the thrust sheet (hanging wall horses) splayed of f and accreted to the footwall ramp zone. A detailed retrodeformable (balanced) regional structure section suggests that fold-thrust shortening at the latitude of the Mormon Mountains is a minimum of about 26%. Extension-related structures overprint older fold-thrust structures in the Mormon Mountains. The west-plunging east-trending Candy Peak syncline is one of a family of fold structures related to basin-range rifting. The syncline formed in pre-Miocene time in association with the northeast-striking Reber Mountain normal fault directly north and the northeast-striking Dry Canyon right-lateral strike-slip fault directly south. The Tortoise Flat synform, which lies southeast of the Dry Canyon fault, developed in Miocene and possibly Pliocene time by right-lateral flexure of early Miocene Horse Spring beds as a result of drag associated with the Dry Canyon fault. The Dry Canyon fault and the Tortoise Flat synform are interpreted to be part of the right-lateral Moapa Peak-Reber Mountain shear zone system in the southern Mormon Mountains. Therefore, the time of formation of the Moapa Peak-Reber Mountain shear zone system is pre-Miocene to possibly Pliocene. The shear zone system formed in response to different amounts of west-directed extension-related movement of the hanging wall block of the high-angle Virgin Beaver Dam Mountains fault, which initiated in the Oligocene. From this, the timing of the Moapa Peak-Reber Mountain shear zone, system is interpreted as Oligocene to Miocene, and possibly Pliocene. The interpretation of 261 km of seismic reflection sections suggests that large-displacement high-angle normal faults, typically with 60 degrees of dip, control horst and graben structure and accommodate extension by simple shear in the upper brittle crust. Such faults likely extend to depths of 15 to 18 km. Below this depth extension is thought to be accommodated by penetrative ductile deformation. A detailed retrodeformable (balanced) regional structure section suggests that basin-range extension at the latitude of the Mormon Mountains is about 17%. The Virgin-Beaver Dam Mountains high-angle normal fault is a large-displacement master fault in the area, having more than 8,000 in of normal vertical separation at the latitude of the Virgin Valley basin depocenter. Miocene doming and uplift of the Mormon Mountains occurred in response to displacement on the Virgin-Beaver Dam Mountains fault. The Virgin Valley basin formed as the hanging wall block downdropped, and the Mormon Mountains dome formed by relative uplift at the opposite end of the hanging wall block. Half-grabens, and tilted, folded, and faulted range blocks characterize basin-range crustal structure. Depositional growth relations are interpreted in basins from fanning-upward reflector geometry, and the wedge-shape of Oligocene to Recent syntectonic basin-fill sediments. Non-overlapping opposing east- and west-tilted half-grabens compose the Meadow Valley-California Wash basin. Seismic sections, gravity data, well data, and geologic mapping demonstrate that the Mormon Peak, Tule Springs Hills, and Beaver Dam/Castle Cliff "detachments," which were thought to be rooted low-angle normal faults, do not exist. The Mormon Peak and Beaver Dam/Castle Cliff low-angle normal faults are denudational fault planes below gravity slid masses. The widely distributed translocated Paleozoic blocks, which were thought to be remnant pieces of large hanging wall sheets ("extensional allochthons"), are disjunct rootless gravity slide blocks of minor tectonic significance. A large number of these rootless slide blocks lie on Pliocene and Quaternary basin-fill deposits. The Muddy Mountain-Tule Springs thrust, of Sevier age, was not reactivated as a crustal penetrating Tule Springs Hills low-angle normal fault, but is affected by small-scale gravity slide features. Rootless gravity slide blocks, secondary features to high-angle normal faults, commonly occur from instability as a result of the loss of lateral support induced by block faulting and the associated erosion of range blocks. Title: Structure of the southern Mormon Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona Author: Carpenter, James Anthony Detailed geologic mapping in the Mormon Mountains and new geophysical data provide significant insight into contractional and extensional tectonics in southern Nevada, southwest Utah, and northwest Arizona. The rocks in the region were complexly deformed during two distinct tectonic episodes. Numerous interrelated events occurred within each episode. The first tectonic episode, related to the Sevier orogeny, was characterized by east-west crustal shortening which culminated in thin-skinned decollement style folding and thrusting during the Cretaceous. The Virgin-Beaver Dam Mountains anticline, a Laramide-type basement-involved uplift, represents the only thick-skinned contractional structure in the region. The second tectonic episode, related to basin-range rifting, was characterized by east-west crustal extension which was accommodated by high-angle normal faults, with dips averaging 60 degrees, in the brittle upper crust. In this area, basin-range rifting initiated in the Oligocene and continued to Recent time. Relations in the North Muddy Mountains in southern Nevada suggest that the Muddy Mountain thrust sheet advanced and overrode the Weiser syncline during the Cenomanian and may have continued to advance in Turonian time. In the southern Mormon Mountains, the Cambrian Bonanza King Formation lies in the hanging wall flat position in thrust contact with the overturned Petrified Forest Member of the Triassic Chinle Formation at the footwall ramp. The thrust sheet advanced eastward more than 30 km from the place of origin. Thrust imbrication, and probably the formation of hanging wall horses, likely occurred as the Muddy Mountain thrust sheet encountered and ascended up the footwall ramp zone (composed largely of competent carbonate rocks) where slices of the thrust sheet (hanging wall horses) splayed of f and accreted to the footwall ramp zone. A detailed retrodeformable (balanced) regional structure section suggests that fold-thrust shortening at the latitude of the Mormon Mountains is a minimum of about 26%. Extension-related structures overprint older fold-thrust structures in the Mormon Mountains. The west-plunging east-trending Candy Peak syncline is one of a family of fold structures related to basin-range rifting. The syncline formed in pre-Miocene time in association with the northeast-striking Reber Mountain normal fault directly north and the northeast-striking Dry Canyon right-lateral strike-slip fault directly south. The Tortoise Flat synform, which lies southeast of the Dry Canyon fault, developed in Miocene and possibly Pliocene time by right-lateral flexure of early Miocene Horse Spring beds as a result of drag associated with the Dry Canyon fault. The Dry Canyon fault and the Tortoise Flat synform are interpreted to be part of the right-lateral Moapa Peak-Reber Mountain shear zone system in the southern Mormon Mountains. Therefore, the time of formation of the Moapa Peak-Reber Mountain shear zone system is pre-Miocene to possibly Pliocene. The shear zone system formed in response to different amounts of west-directed extension-related movement of the hanging wall block of the high-angle Virgin Beaver Dam Mountains fault, which initiated in the Oligocene. From this, the timing of the Moapa Peak-Reber Mountain shear zone, system is interpreted as Oligocene to Miocene, and possibly Pliocene. The interpretation of 261 km of seismic reflection sections suggests that large-displacement high-angle normal faults, typically with 60 degrees of dip, control horst and graben structure and accommodate extension by simple shear in the upper brittle crust. Such faults likely extend to depths of 15 to 18 km. Below this depth extension is thought to be accommodated by penetrative ductile deformation. A detailed retrodeformable (balanced) regional structure section suggests that basin-range extension at the latitude of the Mormon Mountains is about 17%. The Virgin-Beaver Dam Mountains high-angle normal fault is a large-displacement master fault in the area, having more than 8,000 in of normal vertical separation at the latitude of the Virgin Valley basin depocenter. Miocene doming and uplift of the Mormon Mountains occurred in response to displacement on the Virgin-Beaver Dam Mountains fault. The Virgin Valley basin formed as the hanging wall block downdropped, and the Mormon Mountains dome formed by relative uplift at the opposite end of the hanging wall block. Half-grabens, and tilted, folded, and faulted range blocks characterize basin-range crustal structure. Depositional growth relations are interpreted in basins from fanning-upward reflector geometry, and the wedge-shape of Oligocene to Recent syntectonic basin-fill sediments. Non-overlapping opposing east- and west-tilted half-grabens compose the Meadow Valley-California Wash basin. Seismic sections, gravity data, well data, and geologic mapping demonstrate that the Mormon Peak, Tule Springs Hills, and Beaver Dam/Castle Cliff "detachments," which were thought to be rooted low-angle normal faults, do not exist. The Mormon Peak and Beaver Dam/Castle Cliff low-angle normal faults are denudational fault planes below gravity slid masses. The widely distributed translocated Paleozoic blocks, which were thought to be remnant pieces of large hanging wall sheets ("extensional allochthons"), are disjunct rootless gravity slide blocks of minor tectonic significance. A large number of these rootless slide blocks lie on Pliocene and Quaternary basin-fill deposits. The Muddy Mountain-Tule Springs thrust, of Sevier age, was not reactivated as a crustal penetrating Tule Springs Hills low-angle normal fault, but is affected by small-scale gravity slide features. Rootless gravity slide blocks, secondary features to high-angle normal faults, commonly occur from instability as a result of the loss of lateral support induced by block faulting and the associated erosion of range blocks. Close

• 12298. [Article] Identifying habitat factors for canary rockfish (Sebastes pinniger) off Washington and Oregon using environmental data and trawl logbooks

  If fisheries managers are to effectively manage commercially exploited fish populations, a basic understanding of the factors that influence fish distribution and abundance is required. In 2005, efforts ...

  Citation × Citation Citation Abstract Copy Title: Identifying habitat factors for canary rockfish (Sebastes pinniger) off Washington and Oregon using environmental data and trawl logbooks Author: Vestfals, Cathleen D. If fisheries managers are to effectively manage commercially exploited fish populations, a basic understanding of the factors that influence fish distribution and abundance is required. In 2005, efforts to identify Essential Fish Habitat (EFH) for the 82 groundfish species managed by the Pacific Fishery Management Council along the West Coast resulted in the entire continental margin being designated as EFH. Clearly, our knowledge of EFH needs to be refined, which can be accomplished by gaining insight into how environmental variables shape the distribution of managed species. Habitat is commonly used to describe a set of environmental variables that are thought to influence occupancy. The aim of this thesis research is to detect and analyze the quantitative relationships between canary rockfish (Sebastes pinniger) presence/absence data, their spatial distribution, and various biotic and abiotic factors. The presence of canary rockfish at various locations was correlated against co-located environmental variables including bottom depths, temperatures, locations (latitude and longitude), seafloor substrate types, canary rockfish hotspots, and the presence/absence of other groundfish and invertebrate species. The statistical analysis was conducted using the generalized additive model (GAM), which is a nonparametric regression technique very well suited to model nonlinear speciesenvironment interactions. The GAM analysis was conducted using information collected from four different data sources. Data collected by the Alaska Fisheries Science Center (AFSC) from 1986 to 2001 provided information at distinct locations and times on the presence/absence of canary rockfish and other groundfish and invertebrate species, and associated depths and temperatures. Seafloor lithology maps for Oregon and Washington and 100-meter gridded bathymetric data, obtained from the Active Tectonics and Seafloor Mapping Lab at Oregon State University, provided information on the physical characteristics of the seafloor. These data were used in conjunction with the AFSC bottom trawl survey data to investigate the relationships between substrate type, slope and rugosity, and the presence of canary rockfish. Finally, locations of canary rockfish hotspots, or areas with high canary rockfish catch, were identified from Oregon commercial trawl logbook data (1995-2001) and provided information on distinct areas where the trawl fishing fleet had successfully caught canary rockfish in the past. Canary rockfish presence in trawl survey tows was associated with specific locations and ranges of bathymetry, temperatures, and substrate types, as well as proximity to canary rockfish hotspots, and particular fish and invertebrate communities. Survey year had a strong effect on the presence of canary rockfish, as did location (latitude and longitude) and depth. The geographic location of a survey tow had a negative effect on the presence of canary rockfish in the nearshore region, and a positive effect the further the location was from the coastline, with canary rockfish presence being highest off the Washington coast between 47.5°N and 48.5°N. While canary rockfish were found at depths between 57 m and 307 m in the survey, the majority of the tows with canary rockfish catch, over 90%, occurred between the depths of 57 m and 199 m. Though temperature did not have a significant effect on canary rockfish presence in the GAM, canary rockfish were associated with specific temperature ranges, only being caught at temperatures between 6.2°C and 9.0°C in the survey. Over 89% of the tows with canary rockfish catch occurred between 6.2°C and 7.9°C. Since temperature and bottom depth of the trawl survey tows were highly correlated, it was difficult to determine which variable was the causative factor in determining the probability of a canary rockfish being present. Canary rockfish presence was higher in survey tows made closer to canary rockfish hotspots, as well as hard bottom types. Finally, the presence of lingcod, yellowtail, silvergray, or redstripe rockfish in a survey tow increased the likelihood of canary rockfish being present, as did the presence of basketstars and corals. By studying the relationships between species and their environment, we can begin to understand the relative importance of how environmental variables shape the distribution of managed species. For ecosystem-based management strategies to be successful, the functional relationships between organisms and their habitat must be understood. The predictive model developed in this study can be used to identify areas off Oregon and Washington where canary rockfish are likely to be found in relation to various habitat factors, and can potentially be used to delineate areas that should be sampled in future surveys of canary rockfish. Additionally, this research will help to improve our understanding of the factors that influence canary rockfish distribution, which may produce a more realistic definition of canary rockfish habitat, and improve assessment. This study specifically focuses on canary rockfish, because this species currently constrains many West Coast fisheries for groundfish, however, the methods outlined here could be applied more generally to other species of interest. Title: Identifying habitat factors for canary rockfish (Sebastes pinniger) off Washington and Oregon using environmental data and trawl logbooks Author: Vestfals, Cathleen D. If fisheries managers are to effectively manage commercially exploited fish populations, a basic understanding of the factors that influence fish distribution and abundance is required. In 2005, efforts to identify Essential Fish Habitat (EFH) for the 82 groundfish species managed by the Pacific Fishery Management Council along the West Coast resulted in the entire continental margin being designated as EFH. Clearly, our knowledge of EFH needs to be refined, which can be accomplished by gaining insight into how environmental variables shape the distribution of managed species. Habitat is commonly used to describe a set of environmental variables that are thought to influence occupancy. The aim of this thesis research is to detect and analyze the quantitative relationships between canary rockfish (Sebastes pinniger) presence/absence data, their spatial distribution, and various biotic and abiotic factors. The presence of canary rockfish at various locations was correlated against co-located environmental variables including bottom depths, temperatures, locations (latitude and longitude), seafloor substrate types, canary rockfish hotspots, and the presence/absence of other groundfish and invertebrate species. The statistical analysis was conducted using the generalized additive model (GAM), which is a nonparametric regression technique very well suited to model nonlinear speciesenvironment interactions. The GAM analysis was conducted using information collected from four different data sources. Data collected by the Alaska Fisheries Science Center (AFSC) from 1986 to 2001 provided information at distinct locations and times on the presence/absence of canary rockfish and other groundfish and invertebrate species, and associated depths and temperatures. Seafloor lithology maps for Oregon and Washington and 100-meter gridded bathymetric data, obtained from the Active Tectonics and Seafloor Mapping Lab at Oregon State University, provided information on the physical characteristics of the seafloor. These data were used in conjunction with the AFSC bottom trawl survey data to investigate the relationships between substrate type, slope and rugosity, and the presence of canary rockfish. Finally, locations of canary rockfish hotspots, or areas with high canary rockfish catch, were identified from Oregon commercial trawl logbook data (1995-2001) and provided information on distinct areas where the trawl fishing fleet had successfully caught canary rockfish in the past. Canary rockfish presence in trawl survey tows was associated with specific locations and ranges of bathymetry, temperatures, and substrate types, as well as proximity to canary rockfish hotspots, and particular fish and invertebrate communities. Survey year had a strong effect on the presence of canary rockfish, as did location (latitude and longitude) and depth. The geographic location of a survey tow had a negative effect on the presence of canary rockfish in the nearshore region, and a positive effect the further the location was from the coastline, with canary rockfish presence being highest off the Washington coast between 47.5°N and 48.5°N. While canary rockfish were found at depths between 57 m and 307 m in the survey, the majority of the tows with canary rockfish catch, over 90%, occurred between the depths of 57 m and 199 m. Though temperature did not have a significant effect on canary rockfish presence in the GAM, canary rockfish were associated with specific temperature ranges, only being caught at temperatures between 6.2°C and 9.0°C in the survey. Over 89% of the tows with canary rockfish catch occurred between 6.2°C and 7.9°C. Since temperature and bottom depth of the trawl survey tows were highly correlated, it was difficult to determine which variable was the causative factor in determining the probability of a canary rockfish being present. Canary rockfish presence was higher in survey tows made closer to canary rockfish hotspots, as well as hard bottom types. Finally, the presence of lingcod, yellowtail, silvergray, or redstripe rockfish in a survey tow increased the likelihood of canary rockfish being present, as did the presence of basketstars and corals. By studying the relationships between species and their environment, we can begin to understand the relative importance of how environmental variables shape the distribution of managed species. For ecosystem-based management strategies to be successful, the functional relationships between organisms and their habitat must be understood. The predictive model developed in this study can be used to identify areas off Oregon and Washington where canary rockfish are likely to be found in relation to various habitat factors, and can potentially be used to delineate areas that should be sampled in future surveys of canary rockfish. Additionally, this research will help to improve our understanding of the factors that influence canary rockfish distribution, which may produce a more realistic definition of canary rockfish habitat, and improve assessment. This study specifically focuses on canary rockfish, because this species currently constrains many West Coast fisheries for groundfish, however, the methods outlined here could be applied more generally to other species of interest. Close

• 12299. [Article] Magma dynamics and evolution in continental arcs : insights from the Central Andes

  Constraining the magma evolution and dynamics that lead to the eruption of large volume continental arc systems is fundamental to our understanding of continental crust formation. An investigation into ...

  Citation × Citation Citation Abstract Copy Title: Magma dynamics and evolution in continental arcs : insights from the Central Andes Author: Grocke, Stephanie B. Constraining the magma evolution and dynamics that lead to the eruption of large volume continental arc systems is fundamental to our understanding of continental crust formation. An investigation into the magmagenesis that results in the formation of the Central Volcanic Zone (CVZ) in the Andes of South America, situated atop overthickened continental crust (<80 km thick), provides insights into large volume silicic magma reservoirs and how they evolve prior to their potentially catastrophic explosive eruption on the Earth’s surface. A focused case study of the Cerro Guacha Caldera Complex (CGCC), a nested volcanic system in the Altiplano-Puna Volcanic Complex of SW Bolivia, puts constraints on the progressive stages of development of the magmatic underpinnings of the caldera complex. Whole rock data, in conjunction with matrix glass, mineral compositions and melt inclusions, are used to infer processes that gave rise to the formation of the Guacha II Caldera, the younger of two main collapse features, formed from the supereruption of the Tara Ignimbrite (>800 km³ DRE) at 3.49 ± 0.01 Ma. The eruptive history of the Guacha II Caldera from pre-caldera to post-caldera is fully represented, allowing magma dynamics associated with a complete caldera cycle, from pre-climactic (catastrophic caldera-forming) magma accumulation through to post-climactic effusions that are part of the resurgent history of the caldera, to be examined. Analysis of the high-K, calcalkaline suite of andesite to high Si-rhyolite Tara pyroclastic deposits provides insights into the storage conditions and magma dynamics leading up to a supervolcanic eruption. The Tara eruptive products define a liquid line of descent from the basal andesite lava (62 wt % SiO₂) to the high-silica rhyolite post-collapse Chajnantor Dome lava (78 wt.% SiO₂), with major and trace element trends consistent with fractionation of quartz, plagioclase, orthopyroxene, hornblende, sanidine, biotite, and Fe-Ti oxides. Isotope ratios span a significant range in ⁸⁷Sr/⁸⁶Sr (0.709 to 0.713) and a relatively narrow range in ¹⁴³Nd/¹⁴⁴Nd (0.512179 to 0.512297) and δ¹⁸O[subscript (qtz)] (+8.68 to +8.43‰). These data require AFC processes to explain both the isotope and trace element compositions in the Tara magmas. Geothermobarometry reveals pre-eruptive temperatures (~800 - 950 °C), pressures (~200 MPa), and H₂O contents (~5 wt%) that suggest storage of a large-volume rhyodacite magma reservoir between 5 and 9 km depth in the upper crust. Analyses of quartz-hosted melt inclusions from pumices in the climactic plinian and ignimbrite phase of eruption reveal that pre-eruptive H₂O contents in the plinian pumice overlap with those in the ignimbrite pumice (2.2 to 6.0 and 2.1 to 5.4 wt.% H₂O, respectively). The ignimbrite magma, however, contains higher CO₂ (<630 versus <300 ppm) suggesting a vertically arranged pre-climactic magma column from 7.5 km to 4 km depth, which is in agreement with the geothermobarometry from mineral analysis. Andesite recharge can account for significant compositional heterogeneities identified in the Tara magmas. Variations in trace element concentrations from melt inclusions from each of the three eruptive phases also suggest that the large-volume pre-climactic reservoir, as well as the remnant magma, contained significant chemical heterogeneities due to variations in the degree of crystal fractionation and the influence of recharge magma. Based on Ti diffusion in quartz, we estimate that the recharge event occurred within <100 years of eruption and may signal the onset of the pressurization of the system that led to eruption. The following petrogenetic model is proposed for the Tara magmatic system: andesite recharge magma ascended into a large-volume rhyodacite magma reservoir in the upper crust, where it cooled and crystallized to form a small volume of rhyolite, crystal-poor, residual melt. Andesite erupted onto what is now the Guacha II caldera-floor, and was followed by an explosive plinian eruption that produced a rhyolite pumice fall deposit outside the caldera to the east and south. Based on melt inclusions, the plinian eruption tapped a less-evolved, crystal poor (~10 vol.%), more roofward liquid that syneruptively mixed with the highly crystalline (<30 vol.%), large volume rhyodacite magma reservoir. Caldera collapse was accompanied by an explosive eruption of the large-volume rhyodacite magma reservoir and subsequent column collapse, resulting in a pyroclastic flow that produced the >800 km³ Tara ignimbrite. Extrusion of three post-caldera domes followed caldera collapse. Subtle differences between these domes invoke separate coexisting "pods" of magma that evolved independently from one another from the remnant magma that is represented by the ignimbrite. Analyses of quartz-hosted melt inclusions from the post-collapse Chajnantor Dome suggest that the highly-differentiated remnant magma contained no detectable CO₂ and low H₂O contents, representative of a degassed magma. The eruptive transition during the climactic eruption was not controlled by the volatile budget of the melt but more likely by external factors such as vent geometry and conduit evolution. Post climactic effusive volcanism reflects the degassed nature of the remnant magma. Using a suite of volcanic rocks from the CVZ, we quantify the effect of assimilation of continental crust on magmatic oxygen fugacity (ƒO₂). We use several proxies to estimate the ƒO₂ recorded by lavas, pumice and scoria: 1) whole rock Fe³⁺/ΣFe ratios, 2) Fe³⁺/ΣFe ratios in quartz-hosted melt inclusions, and 3) Fe-Ti oxide oxybarometry. Samples span a range of crustal contribution, as indicated by their radiogenic isotope compositions (⁸⁷Sr/⁸⁶Sr = 0.705-0.713), and cover the full suite of magma compositions erupted during the Neogene history of the arc (52 - 74 wt.% SiO₂). Some samples show excellent agreement across multiple ƒO₂ proxies. In other cases, where pumices show evidence of alteration in hand-sample for example, the ƒO₂ recorded by bulk Fe³⁺/ΣFe ratios is two orders of magnitude more oxidized than corresponding ratios from melt inclusions or Fe-Ti oxides. This suggests modification of whole rock Fe³⁺/ΣFe ratios, but not melt inclusion Fe³⁺/ΣFe ratios, by syn- or post-eruptive processes and that care must be taken when relying on bulk techniques to determine magmatic ƒO₂. We cannot resolve any oxidation due to crystal fractionation in our sample suite. Crustal assimilation, however, can oxidize arc magmas. The increase in ƒO₂ due to crustal assimilation reaches, but does not exceed, ~1 log unit - even in the Andes, where crustal assimilation is extreme. Title: Magma dynamics and evolution in continental arcs : insights from the Central Andes Author: Grocke, Stephanie B. Constraining the magma evolution and dynamics that lead to the eruption of large volume continental arc systems is fundamental to our understanding of continental crust formation. An investigation into the magmagenesis that results in the formation of the Central Volcanic Zone (CVZ) in the Andes of South America, situated atop overthickened continental crust (<80 km thick), provides insights into large volume silicic magma reservoirs and how they evolve prior to their potentially catastrophic explosive eruption on the Earth’s surface. A focused case study of the Cerro Guacha Caldera Complex (CGCC), a nested volcanic system in the Altiplano-Puna Volcanic Complex of SW Bolivia, puts constraints on the progressive stages of development of the magmatic underpinnings of the caldera complex. Whole rock data, in conjunction with matrix glass, mineral compositions and melt inclusions, are used to infer processes that gave rise to the formation of the Guacha II Caldera, the younger of two main collapse features, formed from the supereruption of the Tara Ignimbrite (>800 km³ DRE) at 3.49 ± 0.01 Ma. The eruptive history of the Guacha II Caldera from pre-caldera to post-caldera is fully represented, allowing magma dynamics associated with a complete caldera cycle, from pre-climactic (catastrophic caldera-forming) magma accumulation through to post-climactic effusions that are part of the resurgent history of the caldera, to be examined. Analysis of the high-K, calcalkaline suite of andesite to high Si-rhyolite Tara pyroclastic deposits provides insights into the storage conditions and magma dynamics leading up to a supervolcanic eruption. The Tara eruptive products define a liquid line of descent from the basal andesite lava (62 wt % SiO₂) to the high-silica rhyolite post-collapse Chajnantor Dome lava (78 wt.% SiO₂), with major and trace element trends consistent with fractionation of quartz, plagioclase, orthopyroxene, hornblende, sanidine, biotite, and Fe-Ti oxides. Isotope ratios span a significant range in ⁸⁷Sr/⁸⁶Sr (0.709 to 0.713) and a relatively narrow range in ¹⁴³Nd/¹⁴⁴Nd (0.512179 to 0.512297) and δ¹⁸O[subscript (qtz)] (+8.68 to +8.43‰). These data require AFC processes to explain both the isotope and trace element compositions in the Tara magmas. Geothermobarometry reveals pre-eruptive temperatures (~800 - 950 °C), pressures (~200 MPa), and H₂O contents (~5 wt%) that suggest storage of a large-volume rhyodacite magma reservoir between 5 and 9 km depth in the upper crust. Analyses of quartz-hosted melt inclusions from pumices in the climactic plinian and ignimbrite phase of eruption reveal that pre-eruptive H₂O contents in the plinian pumice overlap with those in the ignimbrite pumice (2.2 to 6.0 and 2.1 to 5.4 wt.% H₂O, respectively). The ignimbrite magma, however, contains higher CO₂ (<630 versus <300 ppm) suggesting a vertically arranged pre-climactic magma column from 7.5 km to 4 km depth, which is in agreement with the geothermobarometry from mineral analysis. Andesite recharge can account for significant compositional heterogeneities identified in the Tara magmas. Variations in trace element concentrations from melt inclusions from each of the three eruptive phases also suggest that the large-volume pre-climactic reservoir, as well as the remnant magma, contained significant chemical heterogeneities due to variations in the degree of crystal fractionation and the influence of recharge magma. Based on Ti diffusion in quartz, we estimate that the recharge event occurred within <100 years of eruption and may signal the onset of the pressurization of the system that led to eruption. The following petrogenetic model is proposed for the Tara magmatic system: andesite recharge magma ascended into a large-volume rhyodacite magma reservoir in the upper crust, where it cooled and crystallized to form a small volume of rhyolite, crystal-poor, residual melt. Andesite erupted onto what is now the Guacha II caldera-floor, and was followed by an explosive plinian eruption that produced a rhyolite pumice fall deposit outside the caldera to the east and south. Based on melt inclusions, the plinian eruption tapped a less-evolved, crystal poor (~10 vol.%), more roofward liquid that syneruptively mixed with the highly crystalline (<30 vol.%), large volume rhyodacite magma reservoir. Caldera collapse was accompanied by an explosive eruption of the large-volume rhyodacite magma reservoir and subsequent column collapse, resulting in a pyroclastic flow that produced the >800 km³ Tara ignimbrite. Extrusion of three post-caldera domes followed caldera collapse. Subtle differences between these domes invoke separate coexisting "pods" of magma that evolved independently from one another from the remnant magma that is represented by the ignimbrite. Analyses of quartz-hosted melt inclusions from the post-collapse Chajnantor Dome suggest that the highly-differentiated remnant magma contained no detectable CO₂ and low H₂O contents, representative of a degassed magma. The eruptive transition during the climactic eruption was not controlled by the volatile budget of the melt but more likely by external factors such as vent geometry and conduit evolution. Post climactic effusive volcanism reflects the degassed nature of the remnant magma. Using a suite of volcanic rocks from the CVZ, we quantify the effect of assimilation of continental crust on magmatic oxygen fugacity (ƒO₂). We use several proxies to estimate the ƒO₂ recorded by lavas, pumice and scoria: 1) whole rock Fe³⁺/ΣFe ratios, 2) Fe³⁺/ΣFe ratios in quartz-hosted melt inclusions, and 3) Fe-Ti oxide oxybarometry. Samples span a range of crustal contribution, as indicated by their radiogenic isotope compositions (⁸⁷Sr/⁸⁶Sr = 0.705-0.713), and cover the full suite of magma compositions erupted during the Neogene history of the arc (52 - 74 wt.% SiO₂). Some samples show excellent agreement across multiple ƒO₂ proxies. In other cases, where pumices show evidence of alteration in hand-sample for example, the ƒO₂ recorded by bulk Fe³⁺/ΣFe ratios is two orders of magnitude more oxidized than corresponding ratios from melt inclusions or Fe-Ti oxides. This suggests modification of whole rock Fe³⁺/ΣFe ratios, but not melt inclusion Fe³⁺/ΣFe ratios, by syn- or post-eruptive processes and that care must be taken when relying on bulk techniques to determine magmatic ƒO₂. We cannot resolve any oxidation due to crystal fractionation in our sample suite. Crustal assimilation, however, can oxidize arc magmas. The increase in ƒO₂ due to crustal assimilation reaches, but does not exceed, ~1 log unit - even in the Andes, where crustal assimilation is extreme. Close

• 12300. [Article] The role of lutein and zeaxanthin in protecting the retina from light damage

  Purpose: The xanthophyll carotenoids lutein and zeaxanthin are concentrated in the macula lutea of the retina. It is thought that the two plant pigments may play a role in preventing the development of ...

  Citation × Citation Citation Abstract Copy Title: The role of lutein and zeaxanthin in protecting the retina from light damage Author: Derenick, Rhianna A. Purpose: The xanthophyll carotenoids lutein and zeaxanthin are concentrated in the macula lutea of the retina. It is thought that the two plant pigments may play a role in preventing the development of age-related macular degeneration (AMD). Exposure to damaging light plays a role in retinal deterioration and AMD. The antioxidant capabilities of lutein and zeaxanthin, combined with their ability to filter short-wavelength blue light, may serve to protect the retina from photooxidative damage and photoreceptor cell death. In the first study, chicks’ were fed diets supplemented with lutein and zeaxanthin and exposed to damaging light; functionality of the retinas was assessed with electroretinography. The second study attempted to create lutein and zeaxanthin-deficient chicks to investigate carotenoid deficiency and the impact on retinal functionality. Methods: In the first study, 12 newly hatched White Leghorn chicks were fed a control diet or a lutein and zeaxanthin supplemented diet for 32 days. The supplemented diet was prepared by supplementing the control diet with 30g/g of lutein and 15g/g of zeaxanthin. All chicks were raised in cyclic light. At 32 days of age, 6 were exposed to 10 hours of intermittent light. Baseline and post-treatment electroretinography (ERG) data were collected on all groups of chicks, 32 days and 36 days, respectively. Biochemical analysis of lutein and zeaxanthin in plasma, retina, and other tissues was assessed by HPLC at Day 40. In the second study, lutein and zeaxanthin-deficient chicks were to be produced from White Leghorn laying hens fed a deficient diet. Hens were placed on a deficient diet and after 28-30 days mated with a rooster. The subsequent fertilized eggs were collected. The eggs were stored in an incubator for hatching. Biochemical analysis was used to confirm that egg yolks were deficient in lutein and zeaxanthin. Hatched chicks were to be raised on deficient diets for 32 days and exposed to the same methods employed in the first study. Results: In the first study, plasma and tissue levels of chicks significantly increased their contents of lutein with the supplemented diet; the same result was found for zeaxanthin except for the plasma and skin. Interestingly, total zeaxanthin levels were greater in the retina than the total lutein levels in both groups of chicks (6.40 g/g versus 3.62 g/g). In the retina, zeaxanthin also was found to exist in the cis form. There were significantly greater levels of cis in supplemented diet groups independent of light exposure. For both the supplemented and control diet chicks, there were significant differences within baseline and post-treatment ERG responses in non-light exposed and light exposed chicks (F 9.1, p 0.007,=0.05). No significant difference was found for the maximum amplitude or sensitivity (Kd) ERG responses for lutein supplemented or control chicks between treatment groups. In the second study, the lutein and zeaxanthin content of yolks from eggs laid by laying hens fed a carotenoid-deficient diet declined from Day 2 to Day 36 (11.19 g/g and 18.09 g/g to 0.19 g/g and 0.23 g/g, respectively). However, the laying hens suffered dramatic weight loss, decreased egg laying and hatchability, and illness during the course of the experiment. Even with new housing facilities, a new rooster, and increased animal care, the hens did not produce carotenoid-deficient progeny and thus the proposed light exposure experiments could not be accomplished. Conclusions: In the first study, plasma levels and tissues of chicks fed supplemented diets significantly increased in lutein and zeaxanthin concentrations; the retina actually had higher levels of zeaxanthin even though the diet had greater lutein levels. This suggests the retina has a preference for zeaxanthin. The cis isomer of zeaxanthin, which is isomerized from the trans form by bright light, was only present in the retina. However, significantly greater cis was present in the retinas of supplemented diet chicks a result of higher zeaxanthin levels in the diet and not light exposure. In addition, there were no significant differences between control and supplemented diet chicks as a result of light damage in retinal photoreceptor sensitivity and maximum amplitude response. These results indicate that damage to the retinas of both supplemented and control diet chicks did not occur as a result of light damage treatment. In the second study, assessment of retinal function in carotenoid-deficient chicks could not be accomplished due to lack of production of deficient progeny. Lutein and zeaxanthin concentrations in egg yolks dramatically decreased with subsequent deterioration of the maternal hens’ healths. The conclusions drawn from our efforts were that producing carotenoid-deficient chicks from a maternal hen is difficult and perhaps physiologically impossible. Modifying the experimental design for the deficient hen and investigating other methods to produce carotenoid-deficient progeny are necessary for further studies. In conclusion, these two studies were the first attempts at investigating retinal function, dietary intervention, and light damage within the chick model. With greater power and different experimental approaches more promising results that can be generalized for the human eye disease, AMD, may be uncovered. Title: The role of lutein and zeaxanthin in protecting the retina from light damage Author: Derenick, Rhianna A. Purpose: The xanthophyll carotenoids lutein and zeaxanthin are concentrated in the macula lutea of the retina. It is thought that the two plant pigments may play a role in preventing the development of age-related macular degeneration (AMD). Exposure to damaging light plays a role in retinal deterioration and AMD. The antioxidant capabilities of lutein and zeaxanthin, combined with their ability to filter short-wavelength blue light, may serve to protect the retina from photooxidative damage and photoreceptor cell death. In the first study, chicks’ were fed diets supplemented with lutein and zeaxanthin and exposed to damaging light; functionality of the retinas was assessed with electroretinography. The second study attempted to create lutein and zeaxanthin-deficient chicks to investigate carotenoid deficiency and the impact on retinal functionality. Methods: In the first study, 12 newly hatched White Leghorn chicks were fed a control diet or a lutein and zeaxanthin supplemented diet for 32 days. The supplemented diet was prepared by supplementing the control diet with 30g/g of lutein and 15g/g of zeaxanthin. All chicks were raised in cyclic light. At 32 days of age, 6 were exposed to 10 hours of intermittent light. Baseline and post-treatment electroretinography (ERG) data were collected on all groups of chicks, 32 days and 36 days, respectively. Biochemical analysis of lutein and zeaxanthin in plasma, retina, and other tissues was assessed by HPLC at Day 40. In the second study, lutein and zeaxanthin-deficient chicks were to be produced from White Leghorn laying hens fed a deficient diet. Hens were placed on a deficient diet and after 28-30 days mated with a rooster. The subsequent fertilized eggs were collected. The eggs were stored in an incubator for hatching. Biochemical analysis was used to confirm that egg yolks were deficient in lutein and zeaxanthin. Hatched chicks were to be raised on deficient diets for 32 days and exposed to the same methods employed in the first study. Results: In the first study, plasma and tissue levels of chicks significantly increased their contents of lutein with the supplemented diet; the same result was found for zeaxanthin except for the plasma and skin. Interestingly, total zeaxanthin levels were greater in the retina than the total lutein levels in both groups of chicks (6.40 g/g versus 3.62 g/g). In the retina, zeaxanthin also was found to exist in the cis form. There were significantly greater levels of cis in supplemented diet groups independent of light exposure. For both the supplemented and control diet chicks, there were significant differences within baseline and post-treatment ERG responses in non-light exposed and light exposed chicks (F 9.1, p 0.007,=0.05). No significant difference was found for the maximum amplitude or sensitivity (Kd) ERG responses for lutein supplemented or control chicks between treatment groups. In the second study, the lutein and zeaxanthin content of yolks from eggs laid by laying hens fed a carotenoid-deficient diet declined from Day 2 to Day 36 (11.19 g/g and 18.09 g/g to 0.19 g/g and 0.23 g/g, respectively). However, the laying hens suffered dramatic weight loss, decreased egg laying and hatchability, and illness during the course of the experiment. Even with new housing facilities, a new rooster, and increased animal care, the hens did not produce carotenoid-deficient progeny and thus the proposed light exposure experiments could not be accomplished. Conclusions: In the first study, plasma levels and tissues of chicks fed supplemented diets significantly increased in lutein and zeaxanthin concentrations; the retina actually had higher levels of zeaxanthin even though the diet had greater lutein levels. This suggests the retina has a preference for zeaxanthin. The cis isomer of zeaxanthin, which is isomerized from the trans form by bright light, was only present in the retina. However, significantly greater cis was present in the retinas of supplemented diet chicks a result of higher zeaxanthin levels in the diet and not light exposure. In addition, there were no significant differences between control and supplemented diet chicks as a result of light damage in retinal photoreceptor sensitivity and maximum amplitude response. These results indicate that damage to the retinas of both supplemented and control diet chicks did not occur as a result of light damage treatment. In the second study, assessment of retinal function in carotenoid-deficient chicks could not be accomplished due to lack of production of deficient progeny. Lutein and zeaxanthin concentrations in egg yolks dramatically decreased with subsequent deterioration of the maternal hens’ healths. The conclusions drawn from our efforts were that producing carotenoid-deficient chicks from a maternal hen is difficult and perhaps physiologically impossible. Modifying the experimental design for the deficient hen and investigating other methods to produce carotenoid-deficient progeny are necessary for further studies. In conclusion, these two studies were the first attempts at investigating retinal function, dietary intervention, and light damage within the chick model. With greater power and different experimental approaches more promising results that can be generalized for the human eye disease, AMD, may be uncovered. Close