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• 2811. [Article] Weed, water, and nutrient management practices for organic blackberry during establishment

  The study was conducted in an organic trailing blackberry (Rubus L. subgenus Rubus, Watson) planting established at the North Willamette Research and Extension Center in Aurora, OR on 26 May 2010. Three ...

  Citation × Citation Citation Abstract Copy Title: Weed, water, and nutrient management practices for organic blackberry during establishment Author: Harkins, Renee H. The study was conducted in an organic trailing blackberry (Rubus L. subgenus Rubus, Watson) planting established at the North Willamette Research and Extension Center in Aurora, OR on 26 May 2010. Three weed management systems were compared for 'Marion' and 'Black Diamond': 1) non-weeded; 2) hand-hoed two to three times per year (hand weed); and 3) black landscape fabric mulch (weed mat). The planting was certified organic in May 2012, the first fruiting year. Aboveground weed dry weight (DW) increased from 2010 through 2012 in the non-weeded plots. Findings suggest that nitrogen (N) was the major nutrient affecting blackberry cane growth and fruit development. Other nutrients were considered sufficient as evidenced by soil and plant tissue testing, with the exception of calcium (Ca) and boron, which were at the low end of the sufficiency range in some soil and tissue samples. Soil nutrients fluctuated a small amount by distance and location relative to the emitter and sampling depth. However overall nutrient concentrations were adequate for good blackberry growth. Given some of the observed nutrient trends, soil sampling should be completed in-row, under the drip emitters where fertilizer is applied, at a 0.15 cm depth, to ensure proper long-term soil management. Total aboveground plant biomass increased from 0.3 and 2.0 t·ha⁻¹ in the non-fruiting years (2010 and 2011, respectively) to 3.4 t·ha⁻¹ in the fruiting year (2012). Primocane number and plant DW were not affected by cultivar or weed management in 2010. In 2011, 'Black Diamond' had shorter primocanes and less biomass and macro- and micro-nutrient accumulation than 'Marion'. Plants grown without weed control produced fewer but longer primocanes with less biomass and lower nutrient content. In 2012, floricane biomass removed at pruning was greater for ‘Marion’ plants and was least for plants in non-weeded plots, and greatest for plants in weed mat plots. Floricanes had greater macro- and micronutrient concentrations than the primocanes, but less than when the floricane leaves were sampled in July, indicating nutrient loss to the fruit and possibly remobilization of some nutrients during cane senescence. Ultimately, floricanes were also a sink for nutrients, reducing primocane biomass in 2012. During the first harvest year (2012), the cultivars did not differ in the DW yield, however, 'Black Diamond' had a greater fresh yield than 'Marion' (6.0 kg·plant⁻¹ and 5.2 kg·plant⁻¹, respectively). The proportion of above-ground DW biomass allocated to fruit in weed controlled plots averaged 40% in 'Marion' and 56% in 'Black Diamond', suggesting a greater yield efficiency of 'Black Diamond' plants. Non-weeded plots produced approx. half the fresh yield (3.65 kg·plant-1), 39% of the fruit DW biomass as weed mat plots, and the treatment had fruit with lower moisture content, higher percent soluble solids, and lower Ca concentrations, than the other treatments. Net gain of N averaged 41 kg·ha⁻¹ with weed control compared to 25 kg·ha⁻¹ without weed control. Both cultivars accumulated large quantities of N, potassium, and Ca for growth and yield. Nutrient gains may have exceeded fertilizer nutrients available in the fruit production year. Overall, cultivar and weed management strategies had inconsistent effects on tissue and soil nutrient status during the study, with the exception of N. 'Black Diamond' and 'Marion' performed similarly across all three weed management strategies and appeared well suited to organic production for high-value processed markets. Weed mat appeared best suited for organic systems, reducing labor required for weed control, enhancing nutrient uptake by plants, and producing the greatest amount of plant growth and yield. Weed management strategies affected nutrient accumulation and loss, indicating fertilization may need to be adjusted depending on the strategy used. Title: Weed, water, and nutrient management practices for organic blackberry during establishment Author: Harkins, Renee H. The study was conducted in an organic trailing blackberry (Rubus L. subgenus Rubus, Watson) planting established at the North Willamette Research and Extension Center in Aurora, OR on 26 May 2010. Three weed management systems were compared for 'Marion' and 'Black Diamond': 1) non-weeded; 2) hand-hoed two to three times per year (hand weed); and 3) black landscape fabric mulch (weed mat). The planting was certified organic in May 2012, the first fruiting year. Aboveground weed dry weight (DW) increased from 2010 through 2012 in the non-weeded plots. Findings suggest that nitrogen (N) was the major nutrient affecting blackberry cane growth and fruit development. Other nutrients were considered sufficient as evidenced by soil and plant tissue testing, with the exception of calcium (Ca) and boron, which were at the low end of the sufficiency range in some soil and tissue samples. Soil nutrients fluctuated a small amount by distance and location relative to the emitter and sampling depth. However overall nutrient concentrations were adequate for good blackberry growth. Given some of the observed nutrient trends, soil sampling should be completed in-row, under the drip emitters where fertilizer is applied, at a 0.15 cm depth, to ensure proper long-term soil management. Total aboveground plant biomass increased from 0.3 and 2.0 t·ha⁻¹ in the non-fruiting years (2010 and 2011, respectively) to 3.4 t·ha⁻¹ in the fruiting year (2012). Primocane number and plant DW were not affected by cultivar or weed management in 2010. In 2011, 'Black Diamond' had shorter primocanes and less biomass and macro- and micro-nutrient accumulation than 'Marion'. Plants grown without weed control produced fewer but longer primocanes with less biomass and lower nutrient content. In 2012, floricane biomass removed at pruning was greater for ‘Marion’ plants and was least for plants in non-weeded plots, and greatest for plants in weed mat plots. Floricanes had greater macro- and micronutrient concentrations than the primocanes, but less than when the floricane leaves were sampled in July, indicating nutrient loss to the fruit and possibly remobilization of some nutrients during cane senescence. Ultimately, floricanes were also a sink for nutrients, reducing primocane biomass in 2012. During the first harvest year (2012), the cultivars did not differ in the DW yield, however, 'Black Diamond' had a greater fresh yield than 'Marion' (6.0 kg·plant⁻¹ and 5.2 kg·plant⁻¹, respectively). The proportion of above-ground DW biomass allocated to fruit in weed controlled plots averaged 40% in 'Marion' and 56% in 'Black Diamond', suggesting a greater yield efficiency of 'Black Diamond' plants. Non-weeded plots produced approx. half the fresh yield (3.65 kg·plant-1), 39% of the fruit DW biomass as weed mat plots, and the treatment had fruit with lower moisture content, higher percent soluble solids, and lower Ca concentrations, than the other treatments. Net gain of N averaged 41 kg·ha⁻¹ with weed control compared to 25 kg·ha⁻¹ without weed control. Both cultivars accumulated large quantities of N, potassium, and Ca for growth and yield. Nutrient gains may have exceeded fertilizer nutrients available in the fruit production year. Overall, cultivar and weed management strategies had inconsistent effects on tissue and soil nutrient status during the study, with the exception of N. 'Black Diamond' and 'Marion' performed similarly across all three weed management strategies and appeared well suited to organic production for high-value processed markets. Weed mat appeared best suited for organic systems, reducing labor required for weed control, enhancing nutrient uptake by plants, and producing the greatest amount of plant growth and yield. Weed management strategies affected nutrient accumulation and loss, indicating fertilization may need to be adjusted depending on the strategy used. Close

• 2812. [Article] Impacts of Swiss needle cast on Douglas-fir tree-ring stable isotopes and tree carbohydrate reserves

  Understanding the mechanisms of disease in forest pathology is a critical component to learning how to most efficiently manage tree diseases like Swiss needle cast (SNC). SNC is an economically important, ...

  Citation × Citation Citation Abstract Copy Title: Impacts of Swiss needle cast on Douglas-fir tree-ring stable isotopes and tree carbohydrate reserves Author: Saffell, Brandy J. Understanding the mechanisms of disease in forest pathology is a critical component to learning how to most efficiently manage tree diseases like Swiss needle cast (SNC). SNC is an economically important, fungal disease of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) that is prevalent in coastal areas of the Pacific Northwest. This thesis research provides two contributions to the greater understanding of the pathogenic impacts on plant physiological functioning, or pathophysiology, of SNC on Douglas-fir that will ultimately inform management decisions in Pacific Northwest forests affected by SNC. The primary objectives of this thesis research were: (1) to examine the effects of SNC on Douglas-fir tree-ring stable isotope discrimination of carbon (Δ¹³C) and oxygen (δ¹⁸O) and (2) to evaluate the impact of SNC on tree carbohydrate reserves. Thesis Objective 1- I used growth measurements and stable isotopes of carbon and oxygen in tree-rings of Douglas-fir and a non-susceptible reference species (western hemlock, Tsuga heterophylla (Raf.) Sarg.) to evaluate their use as proxies for variation in past SNC infection, particularly in relation to potential explanatory climate factors. Trees were sampled from a site where a fungicide trial took place from 1996 to 2000, which enabled the comparison of years when disease was present and absent, relative to untreated trees which had the infection throughout. Tree-ring Δ¹³C of treated Douglas-fir increased during the treatment period, and was ~1.6 per mil greater than that of untreated Douglas-fir at the end of the years of the fungicide treatment. Both annual growth and tree-ring Δ¹³C increased with treatment such that treated Douglas-fir had values similar to co-occurring western hemlock during the treatment period, which suggests that the use of Δ¹³C in Douglas-fir tree-rings to track SNC disease history may be a practical approach provided a reference species is available to develop a parallel Δ¹³C chronology. There was no difference in tree-ring δ¹⁸O between treated and untreated Douglas-fir. Tree-ring Δ¹³C of diseased Douglas-fir was negatively correlated with relative humidity (RH) during the two previous summers, consistent with increased leaf colonization by SNC under high humidity conditions that then lead to greater disease severity in following years. Thesis Objective 2- The effects of SNC on Douglas-fir carbohydrate reserves were explored to evaluate the extent to which non-structural carbohydrate (NSC) can be mobilized under natural conditions of low water stress and restricted carbon supply in relation to potential demands for growth. Concentrations of starch, sucrose, glucose and fructose were analyzed in twig wood, foliage, and trunk sapwood of 15 Douglas-fir trees expressing a gradient of SNC symptom severity. There were significant negative relationships between disease severity and growth (mean basal area increment, BAI), as well as between disease severity and mean concentration of trunk NSC. The amount of NSC per unit growth (mean NSC/BAI), an index of the relative priority of storage versus growth, increased with disease severity in all three sampled tissues. These results suggest that under reduced carbon supply with SNC, Douglas-fir trees retain NSC at the expense of growth. The crown retains the most NSC, presumably to maintain foliage growth in the spring to compensate for SNC-induced rapid foliage loss in the summer and fall. Title: Impacts of Swiss needle cast on Douglas-fir tree-ring stable isotopes and tree carbohydrate reserves Author: Saffell, Brandy J. Understanding the mechanisms of disease in forest pathology is a critical component to learning how to most efficiently manage tree diseases like Swiss needle cast (SNC). SNC is an economically important, fungal disease of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) that is prevalent in coastal areas of the Pacific Northwest. This thesis research provides two contributions to the greater understanding of the pathogenic impacts on plant physiological functioning, or pathophysiology, of SNC on Douglas-fir that will ultimately inform management decisions in Pacific Northwest forests affected by SNC. The primary objectives of this thesis research were: (1) to examine the effects of SNC on Douglas-fir tree-ring stable isotope discrimination of carbon (Δ¹³C) and oxygen (δ¹⁸O) and (2) to evaluate the impact of SNC on tree carbohydrate reserves. Thesis Objective 1- I used growth measurements and stable isotopes of carbon and oxygen in tree-rings of Douglas-fir and a non-susceptible reference species (western hemlock, Tsuga heterophylla (Raf.) Sarg.) to evaluate their use as proxies for variation in past SNC infection, particularly in relation to potential explanatory climate factors. Trees were sampled from a site where a fungicide trial took place from 1996 to 2000, which enabled the comparison of years when disease was present and absent, relative to untreated trees which had the infection throughout. Tree-ring Δ¹³C of treated Douglas-fir increased during the treatment period, and was ~1.6 per mil greater than that of untreated Douglas-fir at the end of the years of the fungicide treatment. Both annual growth and tree-ring Δ¹³C increased with treatment such that treated Douglas-fir had values similar to co-occurring western hemlock during the treatment period, which suggests that the use of Δ¹³C in Douglas-fir tree-rings to track SNC disease history may be a practical approach provided a reference species is available to develop a parallel Δ¹³C chronology. There was no difference in tree-ring δ¹⁸O between treated and untreated Douglas-fir. Tree-ring Δ¹³C of diseased Douglas-fir was negatively correlated with relative humidity (RH) during the two previous summers, consistent with increased leaf colonization by SNC under high humidity conditions that then lead to greater disease severity in following years. Thesis Objective 2- The effects of SNC on Douglas-fir carbohydrate reserves were explored to evaluate the extent to which non-structural carbohydrate (NSC) can be mobilized under natural conditions of low water stress and restricted carbon supply in relation to potential demands for growth. Concentrations of starch, sucrose, glucose and fructose were analyzed in twig wood, foliage, and trunk sapwood of 15 Douglas-fir trees expressing a gradient of SNC symptom severity. There were significant negative relationships between disease severity and growth (mean basal area increment, BAI), as well as between disease severity and mean concentration of trunk NSC. The amount of NSC per unit growth (mean NSC/BAI), an index of the relative priority of storage versus growth, increased with disease severity in all three sampled tissues. These results suggest that under reduced carbon supply with SNC, Douglas-fir trees retain NSC at the expense of growth. The crown retains the most NSC, presumably to maintain foliage growth in the spring to compensate for SNC-induced rapid foliage loss in the summer and fall. Close

• 2813. [Article] Genetic and environmental differences in age at first estrus and in wool and lamb production of crossbred ewe lambs

  Genetic and environmental factors affecting age of first estrus, wool production, reproduction and lamb production were examined in eight groups of crossbred ewe lambs from two birth years. The 399 ewe ...

  Citation × Citation Citation Abstract Copy Title: Genetic and environmental differences in age at first estrus and in wool and lamb production of crossbred ewe lambs Author: Cedillo, Rose Mary Genetic and environmental factors affecting age of first estrus, wool production, reproduction and lamb production were examined in eight groups of crossbred ewe lambs from two birth years. The 399 ewe lambs whose first year production was analyzed were from eight crossbred groups resulting from mating North Country Cheviot, Dorset, Finnsheep and Romney rams to Suffolk or whiteface Columbia-type range ewes. The ewe lambs were born January through March of both 1973 and 1974, and were raised to weaning on western Oregon hill pastures. They were summered and maintained through the breeding season on irrigated pastures. At the end of the breeding season each year, ewes within each of the eight groups were randomly divided between hill pasture and irrigated valley pasture management systems. After lambing in common facilities, they were returned to the appropriate management environment where they remained throughout lactation. Average age at first estrus for the 90 percent of ewes which did cycle their first fall was 205 days. Age at estrus between years differed by 18 days (P<.01). Sire breed and the sire x dam breed interaction were not significant effects, but ewes with Suffolk dams cycled ten days earlier than ewes with Columbia dams (P<.01). Also a greater proportion of ewes with Columbia dams failed to cycle their first fall (18 percent versus 2 percent for ewes with Suffolk dams). None of the birth year interactions was significant. The regression of age at estrus on birth date of ewe was -.85 days per day (P<.01). The regression of age at estrus on ewe weight at first estrus (estimated by interpolation between bracketing weights) was 0.39 days per pound (P<.01). The unexpected signs of the two regression coefficients probably resulted from shortened day length in the fall triggering estrus at a fairly constant calendar time but at varying ages and weights, depending upon when the lamb was born the previous spring lambing season. Breed of the ewe's dam significantly affected wool grade with Columbia crosses having finer wool. Staple length was longest and about equal for Finn and Romney sired ewes; Dorset crosses produced the shortest wool. Columbia cross wool was longer than Suffolk cross wool only in Finn and Dorset cross ewes. Grease fleece weight of Columbia crosses was consistently heavier than that of Suffolk crosses. Romney sired ewes had the heaviest fleeces followed by Cheviot, Dorset and Finn sired ewes. Observable medullation was most severe in the two Cheviot crossbred groups, with a tendency for slightly greater medullation in Suffolk than in Columbia crosses. Romney x Columbia ewes generated the most wool income, due to heavy fleece weight and high value per pound of clean wool. Ewes with Columbia dams generated higher wool income than did those with Suffolk dams. The reproductive performance of ewes with Finn sires was superior to that of ewes with Dorset, Cheviot or Romney sires, while ewes with Suffolk dams were superior to ewes with Columbia dams. Finn crossbreds had the greater percentage of ewes lambing per ewe bred (72 percent), while Romney x Columbia ewes were lowest (18 percent). Finn sired crossbred ewes averaged 1.62 lambs born per ewe lambing compared to 1.18 for the average of the other crosses. Finn cross ewes excelled for total weight of lamb weaned, followed by Dorset, Cheviot and Romney sired ewes. The greater lamb production of the Suffolk cross ewes more than compensated for their lower wool production. They generated $6.00 more total gross income than did Columbia crosses. Also for gross income, ewes with Finn sires were highest followed by Dorset, Cheviot and Romney sired ewes. Title: Genetic and environmental differences in age at first estrus and in wool and lamb production of crossbred ewe lambs Author: Cedillo, Rose Mary Genetic and environmental factors affecting age of first estrus, wool production, reproduction and lamb production were examined in eight groups of crossbred ewe lambs from two birth years. The 399 ewe lambs whose first year production was analyzed were from eight crossbred groups resulting from mating North Country Cheviot, Dorset, Finnsheep and Romney rams to Suffolk or whiteface Columbia-type range ewes. The ewe lambs were born January through March of both 1973 and 1974, and were raised to weaning on western Oregon hill pastures. They were summered and maintained through the breeding season on irrigated pastures. At the end of the breeding season each year, ewes within each of the eight groups were randomly divided between hill pasture and irrigated valley pasture management systems. After lambing in common facilities, they were returned to the appropriate management environment where they remained throughout lactation. Average age at first estrus for the 90 percent of ewes which did cycle their first fall was 205 days. Age at estrus between years differed by 18 days (P<.01). Sire breed and the sire x dam breed interaction were not significant effects, but ewes with Suffolk dams cycled ten days earlier than ewes with Columbia dams (P<.01). Also a greater proportion of ewes with Columbia dams failed to cycle their first fall (18 percent versus 2 percent for ewes with Suffolk dams). None of the birth year interactions was significant. The regression of age at estrus on birth date of ewe was -.85 days per day (P<.01). The regression of age at estrus on ewe weight at first estrus (estimated by interpolation between bracketing weights) was 0.39 days per pound (P<.01). The unexpected signs of the two regression coefficients probably resulted from shortened day length in the fall triggering estrus at a fairly constant calendar time but at varying ages and weights, depending upon when the lamb was born the previous spring lambing season. Breed of the ewe's dam significantly affected wool grade with Columbia crosses having finer wool. Staple length was longest and about equal for Finn and Romney sired ewes; Dorset crosses produced the shortest wool. Columbia cross wool was longer than Suffolk cross wool only in Finn and Dorset cross ewes. Grease fleece weight of Columbia crosses was consistently heavier than that of Suffolk crosses. Romney sired ewes had the heaviest fleeces followed by Cheviot, Dorset and Finn sired ewes. Observable medullation was most severe in the two Cheviot crossbred groups, with a tendency for slightly greater medullation in Suffolk than in Columbia crosses. Romney x Columbia ewes generated the most wool income, due to heavy fleece weight and high value per pound of clean wool. Ewes with Columbia dams generated higher wool income than did those with Suffolk dams. The reproductive performance of ewes with Finn sires was superior to that of ewes with Dorset, Cheviot or Romney sires, while ewes with Suffolk dams were superior to ewes with Columbia dams. Finn crossbreds had the greater percentage of ewes lambing per ewe bred (72 percent), while Romney x Columbia ewes were lowest (18 percent). Finn sired crossbred ewes averaged 1.62 lambs born per ewe lambing compared to 1.18 for the average of the other crosses. Finn cross ewes excelled for total weight of lamb weaned, followed by Dorset, Cheviot and Romney sired ewes. The greater lamb production of the Suffolk cross ewes more than compensated for their lower wool production. They generated $6.00 more total gross income than did Columbia crosses. Also for gross income, ewes with Finn sires were highest followed by Dorset, Cheviot and Romney sired ewes. Close

• 2814. [Article] Carbon Dynamics in Response to Land Cover Change in Tropical Peatlands, Kalimantan, Indonesia

  This study focuses in providing the knowledge on carbon (C) stocks, emission and ecosystem productivity related to land use/land cover change in tropical peatlands. The field research activities were ...

  Citation × Citation Citation Abstract Copy Title: Carbon Dynamics in Response to Land Cover Change in Tropical Peatlands, Kalimantan, Indonesia Author: Basuki, Imam This study focuses in providing the knowledge on carbon (C) stocks, emission and ecosystem productivity related to land use/land cover change in tropical peatlands. The field research activities were conducted for about 17 months between August 2013 to December 2015, at Pematang Gadung peat dome (peat depth up to 10.5 m), Ketapang Regency, West Kalimantan, Indonesia. The objectives of this study were: a). to quantify C stocks of tropical coastal peat swamp forest, and the potential impact of forest degradation due to draining and logging activities on the forest’s carbon stocks; b). to examine the change in ecosystem C stocks and the potential C emissions in relation to land conversion from intact peat swamp forest (PSF) to logged peat forest (LPSF), early seral (ES) and oil palm plantation (OP); and c). to estimate net primary production (NPP) and net ecosystem production (NEP) in peat swamp forests, logged peat forest, early seral and smallholder - oil palm plantations. The intact peat forest sites have higher total aboveground C stocks (125 Mg C ha-1) than the logged peat forest sites (77 Mg C ha-1). Mean depths of the LPSF was 725 cm and the PSF was 915 cm (p= 0.06). Mean peat carbon stocks at PSF was 4,243 Mg C ha-1, higher than at LPSF that was 3,675 Mg C ha-1. Logging and draining had reduced the biomass of trees and the peat carbon pools. My study demonstrated that tropical coastal PSF has the largest total carbon stocks among terrestrial ecosystems on earth. The large carbon stocks and high rates of PSF degradation, points to the relevance for inclusion of PSF in nationally appropriate climate change mitigation and adaptation strategies. The mean ecosystem carbon stock for the PSF sites was 4,401 Mg C ha-1. Ecosystem C stocks of LPSF, ES and OP was 3,768, 3,147, and 3,442 Mg C ha-1, respectively. PSF stocks was significantly higher than the degraded land covers. At all sites, soils comprised > 96% of the mean ecosystem carbon stock. Using the estimation based on ecosystem carbon loss to total peat depths, the conversion of PSF to LPSF, ES and OP was estimated to result in a net loss of 1,982, 4,259 and 3,176 Mg C-CO2 ha-1, respectively. My results confirm that land cover change significantly impacted soil properties and reduced ecosystem carbon stocks. The tropical peatlands need urgent and significant efforts in conservation and restoration, to regain its function as a C sink and mitigate climate change. I found that land use/land cover change resulted in large shifts in NPP and NEP. LPSF, ES and OP have significantly lower NPP (11.1 Mg C ha-1 yr-1, 10.8 Mg C ha-1 yr-1 and 3.7 Mg C ha-1 yr-1, respectively) than PSF (13.2 Mg C ha-1 yr-1). ES showed lower heterotrophic respiration (30.7 Mg CO2 ha-1 yr-1) than PSF, LPSF and OP (37.7 Mg CO2 ha-1 yr-1, 40.7 Mg CO2 ha-1 yr-1, 38.7 Mg CO2 ha-1 yr-1, respectively). LPSF and OP were net carbon sources; they have negative mean NEP values (-0.1 Mg CO2-e ha-1 yr-1 and -25.1 Mg CO2-e ha-1 yr-1, respectively). In contrast PSF and ES were net carbon sinks (10.8 Mg CO2-e ha-1 yr-1 and 9.1 CCO2 ha-1 yr-1, respectively). PSF is among the most productive of terrestrial ecosystems, with an NPP exceeding that of many tropical rain forests and similar to the most productive mangrove ecosystems. I found that land use decreases productivity of the LPSF and OP sites. The ES had a similar NEP to the PSF, but frequent fires in this ecosystem likely offset carbon gains during the fire intervals. Land use change and forest degradation have shifted tropical PSFs from net carbon sinks to net carbon sources. My study demonstrated that land conversion in tropical peat swamp forests should be halted and degraded peatlands need to be restored in order to mitigate climate change. Title: Carbon Dynamics in Response to Land Cover Change in Tropical Peatlands, Kalimantan, Indonesia Author: Basuki, Imam This study focuses in providing the knowledge on carbon (C) stocks, emission and ecosystem productivity related to land use/land cover change in tropical peatlands. The field research activities were conducted for about 17 months between August 2013 to December 2015, at Pematang Gadung peat dome (peat depth up to 10.5 m), Ketapang Regency, West Kalimantan, Indonesia. The objectives of this study were: a). to quantify C stocks of tropical coastal peat swamp forest, and the potential impact of forest degradation due to draining and logging activities on the forest’s carbon stocks; b). to examine the change in ecosystem C stocks and the potential C emissions in relation to land conversion from intact peat swamp forest (PSF) to logged peat forest (LPSF), early seral (ES) and oil palm plantation (OP); and c). to estimate net primary production (NPP) and net ecosystem production (NEP) in peat swamp forests, logged peat forest, early seral and smallholder - oil palm plantations. The intact peat forest sites have higher total aboveground C stocks (125 Mg C ha-1) than the logged peat forest sites (77 Mg C ha-1). Mean depths of the LPSF was 725 cm and the PSF was 915 cm (p= 0.06). Mean peat carbon stocks at PSF was 4,243 Mg C ha-1, higher than at LPSF that was 3,675 Mg C ha-1. Logging and draining had reduced the biomass of trees and the peat carbon pools. My study demonstrated that tropical coastal PSF has the largest total carbon stocks among terrestrial ecosystems on earth. The large carbon stocks and high rates of PSF degradation, points to the relevance for inclusion of PSF in nationally appropriate climate change mitigation and adaptation strategies. The mean ecosystem carbon stock for the PSF sites was 4,401 Mg C ha-1. Ecosystem C stocks of LPSF, ES and OP was 3,768, 3,147, and 3,442 Mg C ha-1, respectively. PSF stocks was significantly higher than the degraded land covers. At all sites, soils comprised > 96% of the mean ecosystem carbon stock. Using the estimation based on ecosystem carbon loss to total peat depths, the conversion of PSF to LPSF, ES and OP was estimated to result in a net loss of 1,982, 4,259 and 3,176 Mg C-CO2 ha-1, respectively. My results confirm that land cover change significantly impacted soil properties and reduced ecosystem carbon stocks. The tropical peatlands need urgent and significant efforts in conservation and restoration, to regain its function as a C sink and mitigate climate change. I found that land use/land cover change resulted in large shifts in NPP and NEP. LPSF, ES and OP have significantly lower NPP (11.1 Mg C ha-1 yr-1, 10.8 Mg C ha-1 yr-1 and 3.7 Mg C ha-1 yr-1, respectively) than PSF (13.2 Mg C ha-1 yr-1). ES showed lower heterotrophic respiration (30.7 Mg CO2 ha-1 yr-1) than PSF, LPSF and OP (37.7 Mg CO2 ha-1 yr-1, 40.7 Mg CO2 ha-1 yr-1, 38.7 Mg CO2 ha-1 yr-1, respectively). LPSF and OP were net carbon sources; they have negative mean NEP values (-0.1 Mg CO2-e ha-1 yr-1 and -25.1 Mg CO2-e ha-1 yr-1, respectively). In contrast PSF and ES were net carbon sinks (10.8 Mg CO2-e ha-1 yr-1 and 9.1 CCO2 ha-1 yr-1, respectively). PSF is among the most productive of terrestrial ecosystems, with an NPP exceeding that of many tropical rain forests and similar to the most productive mangrove ecosystems. I found that land use decreases productivity of the LPSF and OP sites. The ES had a similar NEP to the PSF, but frequent fires in this ecosystem likely offset carbon gains during the fire intervals. Land use change and forest degradation have shifted tropical PSFs from net carbon sinks to net carbon sources. My study demonstrated that land conversion in tropical peat swamp forests should be halted and degraded peatlands need to be restored in order to mitigate climate change. Close

• 2815. [Article] Scaffold reactivity and large scale Synthesis of organocatalyzed Yamada-Otani Condensation product and investigation of the synthesis and properties of axially chiral 8,8'-biquinolyls and 8-(naphtha-1-yl)quinolines

  In Part I, (4S,5R)-4,5-dimethyl-4-phenylcyclohex-2-enone (19a) was prepared in 73% yield with high enantio- and diastereo-selectivity (er > 98:2, dr > 20:1) on a multigram scale by a Yamada-Otani condensation ...

  Citation × Citation Citation Abstract Copy Title: Scaffold reactivity and large scale Synthesis of organocatalyzed Yamada-Otani Condensation product and investigation of the synthesis and properties of axially chiral 8,8'-biquinolyls and 8-(naphtha-1-yl)quinolines Author: Banerjee, Somdev In Part I, (4S,5R)-4,5-dimethyl-4-phenylcyclohex-2-enone (19a) was prepared in 73% yield with high enantio- and diastereo-selectivity (er > 98:2, dr > 20:1) on a multigram scale by a Yamada-Otani condensation between (E)-pent-3-en-2-one and 2-phenylpropanal catalyzed by a sulfonimide derivative of (S)-proline (18, HuaCat®). Synthetically useful transformations of the cyclohexenone product 19a were demonstrated, as follows: (a) alpha-alkylation via Li-enolate formation (e.g., LDA, DMPU, MeI, THF, –78 °C, 2 h; 86% yield, dr > 20:1), (b) 1,2-addition of organolithiums (e.g., PhLi, THF, –78 °C, 2 h; 82% yield, dr > 20:1), and (c) 1,4-addition of cyanocuprates (e.g., n-BuLi, CuCN, THF, –78 °C, 2 h; 90% yield, dr > 20:1). In Part II, an azaanalog of 1,1´-bi-2-naphthol (BINOL, 38), 7-hydroxy-8-(2-hydroxynaphth-1-yl)quinoline (8-azaBINOL, 67), was prepared in 3 steps and 49% yield from N,N-diethyl O-(7-hydroxy-8-iodoquinolyl) carbamate via Suzuki coupling with 1-naphthyl-boronic acid followed by Sanford oxidation and saponification. 8- AzaBINOL (67) was resolved into (–)-(aS) and (+)-(aR) atropisomers by enzymatic hydrolysis of its racemic divalerate derivative with bovine pancreas acetone powder. The configurational stability of 8-azaBINOL (67) was found to be intermediate to that of 7,7´-dihydroxy-8,8´-biquinolyl ('8,8´-diazaBINOL', 50, least stable) and BINOL (38, most stable). Eyring plot analysis of the enantiomerization kinetics of 50, 67, and 38, in DMSO solution revealed activation parameters of ΔH‡ = +27.4, +19.9, +23.2 kcal mol–1, and ΔS‡ = +3.8, –27.9, –25.3 cal mol–1 K–1, respectively. The unique character of ΔH‡ and ΔS‡ values for biquinolyl 50 suggests that the enantiomerization mechanism for 50 is distinct to that for naphthalenes 67 and 38. Monohydroxy analogs of 67, 7-hydroxy-8-(naphth-1-yl)quinoline (71) and 8-(2-hydroxynaphth-1-yl)quinoline (75), were similarly prepared and their racemization half-lives at rt were determined; τ1/2(rac.) was strongly dependent on solvent for naphthol 75 (τ1/2(rac.) at 24 °C: in CHCl3 = 2.7 h, in MeOH = 89 h) but not for the quinol 71 (τ1/2(rac.) at 24 °C: in CHCl3 = 106 h, in MeOH = 120 h). 8-AzaBINOL (67) and its tosylic acid salt (67•TsOH) were evaluated as potential hydrogen-bonding / Brønsted acid organocatalysts for enantioselective carbon-carbon bond forming processes. Neither form of the compound was an effective catalyst for the Henry reaction between nitromethane and benzaldehyde nor the conjugate addition of acetylacetone to beta-nitrostyrene; however, these quinols did promote the addition of nucleophilic arenes to pyruvate esters (albeit with low enantioselectivity). For example, addition of indole to ethyl trifluoropyruvate (Et2O, –78 °C) gave the expected beta-substituted indole product [(S)-87] in 98% yield and with 5% ee in the presence of free base (S)-67 (10 mol%). The same organocatalyst did not promote addition of indole to ethyl pyruvate (Et2O, –40 °C) but its more reactive tosylate salt (S)-67•TsOH did, resulting in an 82% yield of the addition product with 3% ee. In a collaborative study (with R. Overacker and S. Loesgen), a 45-member library of 8-azaBINOL and 8,8´-diazaBINOL derivatives was evaluated for biological activity in cytotoxicity/cell viability and HIV viral entry inhibition assays. The isopropyl ether of 7-hydroxy-8-(naphth-1-yl)quinoline (92) and the analogous N,N-diethyl carbamate (69) exhibited the most significant bioactivity with respective IC50 = 4.74 μM and 5.18 μM for inhibition of HIV-1 entry into TZM-b1 cells. Comparable 8,8´-diazaBINOLs did not inhibit viral entry. Specific binding of isopropyl ether 92 to purified and immobilized HIV-1 glycoprotein 120 with a KD = 22 ± 2.9 μM was established using biolayer interferometry. Title: Scaffold reactivity and large scale Synthesis of organocatalyzed Yamada-Otani Condensation product and investigation of the synthesis and properties of axially chiral 8,8'-biquinolyls and 8-(naphtha-1-yl)quinolines Author: Banerjee, Somdev In Part I, (4S,5R)-4,5-dimethyl-4-phenylcyclohex-2-enone (19a) was prepared in 73% yield with high enantio- and diastereo-selectivity (er > 98:2, dr > 20:1) on a multigram scale by a Yamada-Otani condensation between (E)-pent-3-en-2-one and 2-phenylpropanal catalyzed by a sulfonimide derivative of (S)-proline (18, HuaCat®). Synthetically useful transformations of the cyclohexenone product 19a were demonstrated, as follows: (a) alpha-alkylation via Li-enolate formation (e.g., LDA, DMPU, MeI, THF, –78 °C, 2 h; 86% yield, dr > 20:1), (b) 1,2-addition of organolithiums (e.g., PhLi, THF, –78 °C, 2 h; 82% yield, dr > 20:1), and (c) 1,4-addition of cyanocuprates (e.g., n-BuLi, CuCN, THF, –78 °C, 2 h; 90% yield, dr > 20:1). In Part II, an azaanalog of 1,1´-bi-2-naphthol (BINOL, 38), 7-hydroxy-8-(2-hydroxynaphth-1-yl)quinoline (8-azaBINOL, 67), was prepared in 3 steps and 49% yield from N,N-diethyl O-(7-hydroxy-8-iodoquinolyl) carbamate via Suzuki coupling with 1-naphthyl-boronic acid followed by Sanford oxidation and saponification. 8- AzaBINOL (67) was resolved into (–)-(aS) and (+)-(aR) atropisomers by enzymatic hydrolysis of its racemic divalerate derivative with bovine pancreas acetone powder. The configurational stability of 8-azaBINOL (67) was found to be intermediate to that of 7,7´-dihydroxy-8,8´-biquinolyl ('8,8´-diazaBINOL', 50, least stable) and BINOL (38, most stable). Eyring plot analysis of the enantiomerization kinetics of 50, 67, and 38, in DMSO solution revealed activation parameters of ΔH‡ = +27.4, +19.9, +23.2 kcal mol–1, and ΔS‡ = +3.8, –27.9, –25.3 cal mol–1 K–1, respectively. The unique character of ΔH‡ and ΔS‡ values for biquinolyl 50 suggests that the enantiomerization mechanism for 50 is distinct to that for naphthalenes 67 and 38. Monohydroxy analogs of 67, 7-hydroxy-8-(naphth-1-yl)quinoline (71) and 8-(2-hydroxynaphth-1-yl)quinoline (75), were similarly prepared and their racemization half-lives at rt were determined; τ1/2(rac.) was strongly dependent on solvent for naphthol 75 (τ1/2(rac.) at 24 °C: in CHCl3 = 2.7 h, in MeOH = 89 h) but not for the quinol 71 (τ1/2(rac.) at 24 °C: in CHCl3 = 106 h, in MeOH = 120 h). 8-AzaBINOL (67) and its tosylic acid salt (67•TsOH) were evaluated as potential hydrogen-bonding / Brønsted acid organocatalysts for enantioselective carbon-carbon bond forming processes. Neither form of the compound was an effective catalyst for the Henry reaction between nitromethane and benzaldehyde nor the conjugate addition of acetylacetone to beta-nitrostyrene; however, these quinols did promote the addition of nucleophilic arenes to pyruvate esters (albeit with low enantioselectivity). For example, addition of indole to ethyl trifluoropyruvate (Et2O, –78 °C) gave the expected beta-substituted indole product [(S)-87] in 98% yield and with 5% ee in the presence of free base (S)-67 (10 mol%). The same organocatalyst did not promote addition of indole to ethyl pyruvate (Et2O, –40 °C) but its more reactive tosylate salt (S)-67•TsOH did, resulting in an 82% yield of the addition product with 3% ee. In a collaborative study (with R. Overacker and S. Loesgen), a 45-member library of 8-azaBINOL and 8,8´-diazaBINOL derivatives was evaluated for biological activity in cytotoxicity/cell viability and HIV viral entry inhibition assays. The isopropyl ether of 7-hydroxy-8-(naphth-1-yl)quinoline (92) and the analogous N,N-diethyl carbamate (69) exhibited the most significant bioactivity with respective IC50 = 4.74 μM and 5.18 μM for inhibition of HIV-1 entry into TZM-b1 cells. Comparable 8,8´-diazaBINOLs did not inhibit viral entry. Specific binding of isopropyl ether 92 to purified and immobilized HIV-1 glycoprotein 120 with a KD = 22 ± 2.9 μM was established using biolayer interferometry. Close

• 2816. [Article] Carboxylesterases in the house fly (Musca domestica, L.), flesh fly (Sarcophaga bullata, Park.), and black blow fly (Phormia regina, Meig.)

  The carboxylesterases of three species of diptera, the flesh fly (Sarcophaga bullata, Park.), the black blow fly (Phormia regina, Meig.), and the house fly (Musca domestica, L.) were compared in relation to ...

  Citation × Citation Citation Abstract Copy Title: Carboxylesterases in the house fly (Musca domestica, L.), flesh fly (Sarcophaga bullata, Park.), and black blow fly (Phormia regina, Meig.) Author: Maa, Can-jen William The carboxylesterases of three species of diptera, the flesh fly (Sarcophaga bullata, Park.), the black blow fly (Phormia regina, Meig.), and the house fly (Musca domestica, L.) were compared in relation to hydrolytic activity against three substrates, response to inhibition and induction, isozyme composition, and age-dependent variation in activity. Similar studies were also conducted with an insecticide-resistant house fly strain. Most of the experiments were with adult female flies but male flies as well as larvae and pupae were included in several experiments. Naphthyl acetate was the substrate common to all experiments and the esterases hydrolyzing this compound were further characterized according to their inhibition by eserine, parahydroxymecuribenzoate (PHNB), and paraoxon. The hydrolytic activity observed in the presence of eserine and PHNB or blocked by paraoxon was considered to be due to carboxylesterases of the B-type. Two other esters, hydroprene, an insect growth regulator similar in structure to the natural juvenile hormone, and juvenile hormone-1, were also used as substrates. Neither the hemolymph nor the cytosol esterases of the three species were susceptible to eserine inhibition, indicating that the samples contained minor quantities of the choline esterases. PHNB had little inhibitory effect on the flesh fly esterases of both hemolymph and soluble fraction. However, this inhibitor reduced the activity of the blow fly esterases by more than 50 percent, indicating a high content of aryl esterases in this species. The house fly esterases were also inhibited by PHNB but to a less extent than those of the blow fly. As expected, paraoxon was a strong inhibitor of the esterases in both hemolymph and soluble fraction of the three species. The total enzyme content of the flies was estimated from the hemolymph volumes determined earlier and the activity per unit volume found in the age-dependency experiments. The daily average activity estimated in this way was highest in the flesh fly, about four times that of the blow fly, and lowest in the house fly, about one-seventh that of the flesh fly. The values were even lower in the case of the resistant house flies, about 1/40th those of the flesh fly. When hydroprene was used as a substrate in the age-dependency experiments, the activity profiles were similar to those found with naphthyl acetate as substrate indicating that the same enzymes were involved in the hydrolysis of this JH analogue. Of the three species, the flesh fly esterases were most active against hydroprene and the blow fly and resistant house fly enzymes were the least active. The flesh fly hemolymph enzymes averaged, on a per-day basis, up to three times more hydroprene cleaving activity than those of the resistant house flies. The electrophorese experiments with hemolymph and cytosol revealed the presence of several carboxylesterase isozymes. As many as 14 different esterase-active bands were found in flesh fly hemolymph, 11 in blow fly hemolymph, and 12 in house fly hemolymph. Similar results were obtained with the cytosol. These bands were placed in five groups according to their mobilities in the poly acrylamide gels and it was evident that the isozymes migrating to the midpoint of the gels were responsible for most of the carboxylesterase activity. Some slow-moving isozymes were also thought to be responsible for this type of activity. Other evidence obtained during the electrophoreses experiments indicated that the isozymes hydrolizing hydroprene were from the same groups as those cleaving naphthyl-acetate while those which attacked JH-1 had different electrophoretic characteristics. Both hydroprene and naphthyl acetate esterases were induced by topically applied hydroprene. The response was dose dependent in the range 1-10 ug for flesh flies and 1-5 ug for house flies and blow flies. However, the response was variable and appeared to depend on the age of the flies at the time of the treatment. Increases in esterase activity ranged from 1.5 to 4-fold with the flesh fly enzymes being the most responsive and those of the blow fly the least. The possibility of JH-1 esterase induction by hydroprene was not investigated. Title: Carboxylesterases in the house fly (Musca domestica, L.), flesh fly (Sarcophaga bullata, Park.), and black blow fly (Phormia regina, Meig.) Author: Maa, Can-jen William The carboxylesterases of three species of diptera, the flesh fly (Sarcophaga bullata, Park.), the black blow fly (Phormia regina, Meig.), and the house fly (Musca domestica, L.) were compared in relation to hydrolytic activity against three substrates, response to inhibition and induction, isozyme composition, and age-dependent variation in activity. Similar studies were also conducted with an insecticide-resistant house fly strain. Most of the experiments were with adult female flies but male flies as well as larvae and pupae were included in several experiments. Naphthyl acetate was the substrate common to all experiments and the esterases hydrolyzing this compound were further characterized according to their inhibition by eserine, parahydroxymecuribenzoate (PHNB), and paraoxon. The hydrolytic activity observed in the presence of eserine and PHNB or blocked by paraoxon was considered to be due to carboxylesterases of the B-type. Two other esters, hydroprene, an insect growth regulator similar in structure to the natural juvenile hormone, and juvenile hormone-1, were also used as substrates. Neither the hemolymph nor the cytosol esterases of the three species were susceptible to eserine inhibition, indicating that the samples contained minor quantities of the choline esterases. PHNB had little inhibitory effect on the flesh fly esterases of both hemolymph and soluble fraction. However, this inhibitor reduced the activity of the blow fly esterases by more than 50 percent, indicating a high content of aryl esterases in this species. The house fly esterases were also inhibited by PHNB but to a less extent than those of the blow fly. As expected, paraoxon was a strong inhibitor of the esterases in both hemolymph and soluble fraction of the three species. The total enzyme content of the flies was estimated from the hemolymph volumes determined earlier and the activity per unit volume found in the age-dependency experiments. The daily average activity estimated in this way was highest in the flesh fly, about four times that of the blow fly, and lowest in the house fly, about one-seventh that of the flesh fly. The values were even lower in the case of the resistant house flies, about 1/40th those of the flesh fly. When hydroprene was used as a substrate in the age-dependency experiments, the activity profiles were similar to those found with naphthyl acetate as substrate indicating that the same enzymes were involved in the hydrolysis of this JH analogue. Of the three species, the flesh fly esterases were most active against hydroprene and the blow fly and resistant house fly enzymes were the least active. The flesh fly hemolymph enzymes averaged, on a per-day basis, up to three times more hydroprene cleaving activity than those of the resistant house flies. The electrophorese experiments with hemolymph and cytosol revealed the presence of several carboxylesterase isozymes. As many as 14 different esterase-active bands were found in flesh fly hemolymph, 11 in blow fly hemolymph, and 12 in house fly hemolymph. Similar results were obtained with the cytosol. These bands were placed in five groups according to their mobilities in the poly acrylamide gels and it was evident that the isozymes migrating to the midpoint of the gels were responsible for most of the carboxylesterase activity. Some slow-moving isozymes were also thought to be responsible for this type of activity. Other evidence obtained during the electrophoreses experiments indicated that the isozymes hydrolizing hydroprene were from the same groups as those cleaving naphthyl-acetate while those which attacked JH-1 had different electrophoretic characteristics. Both hydroprene and naphthyl acetate esterases were induced by topically applied hydroprene. The response was dose dependent in the range 1-10 ug for flesh flies and 1-5 ug for house flies and blow flies. However, the response was variable and appeared to depend on the age of the flies at the time of the treatment. Increases in esterase activity ranged from 1.5 to 4-fold with the flesh fly enzymes being the most responsive and those of the blow fly the least. The possibility of JH-1 esterase induction by hydroprene was not investigated. Close

• 2817. [Article] Geochemistry of Plutonic Rocks of the Western Cascades, Washington & Oregon : Relationship to Crustal Segmentation and Ore Genesis

  The volcanic (~45-10 Ma) and plutonic rocks (~37-12 Ma) comprising the Western Cascades extend from northernmost California to southern British Columbia and are ancestral to modern arc magmatism. The ancestral ...

  Citation × Citation Citation Abstract Copy Title: Geochemistry of Plutonic Rocks of the Western Cascades, Washington & Oregon : Relationship to Crustal Segmentation and Ore Genesis Author: Utevsky, Elinor S. The volcanic (~45-10 Ma) and plutonic rocks (~37-12 Ma) comprising the Western Cascades extend from northernmost California to southern British Columbia and are ancestral to modern arc magmatism. The ancestral arc hosts a series of small plutons that are locally associated with porphyry (Cu-Mo) and epithermal (Au) ore deposits. Three crustal segments identified by Schmidt et al. (2008, 2013) in the modern arc are potentially reflected in the geochemistry of the ancestral Cascades as well: Paleozoic-Mesozoic accreted terranes, metamorphic rocks, and granites to the north; thin Paleocene Siletzia oceanic crust of the Columbia Embayment in the center; and Paleozoic-Mesozoic ultramafic sheets and marine arc-related volcanic and sedimentary rocks of the Klamath Terrane to the south. Therefore, the Western Cascades of Washington and Oregon provide a field laboratory to examine the chemical compositions and ages of granitoid intrusions associated with a variety of magmatic-hydrothermal ore deposits, and to compare the compositions with the along-arc variation of the age, composition and thickness of the underlying crust. The majority of the 15 new zircon U-Pb ages reported in this study are 27 to 12 Ma with the exception of the ~37 Ma Snoqualmie North Fork intrusions of central WA. A total of 610 zircons were analyzed, of which 118 have ages older than the main population and are considered to be xenocrystic or inherited. The north segment contains the oldest (up to 67 Ma) and most continuous inherited population. The absence of inherited grains older than 67 Ma suggests that neither the North Fork nor White River districts overlie old crystalline crust, but instead overlie Paleocene-Eocene volcanics that are the likely source of inherited zircons. Districts of the Columbia segment have sparse inherited zircon populations (n = 38 of 350 total), ranging from 54 to 20 Ma. The dearth of inherited zircons in the center of the arc suggests limited contamination by a source no older than 55 Ma, likely the dominant Eocene sources of detrital zircon found within the Tyee Formation. Districts overlying the Klamath Terrane have slightly more substantial inherited zircon populations than districts overlying Siletzia but still decidedly few inherited grains (a total of 25 out of 85 grains analyzed, ranging from 44 to 19 Ma); these grains are likely sourced from similar contaminants to those underlying the central segment of the arc, instead of from accreted Mesozoic rocks of the Klamath Terrane. The hypabyssal plutonic rocks represent a small area (~1%) of exposures in the Western Cascades, and range in composition from diorites to granodiorites and minor granite. Fe-Ti oxides, where preserved, include magnetite and ilmenite in proportion of ~2:1, and together with presence of hornblende and biotite are suggestive of modest oxidation states of ~ ΔNNO of 0 to 1 (Carmichael & Nicholls, 1967). Abundant hornblende is observed in 31 of 36 available petrographic sections. Ba/Nb values are not obviously correlated with SiO₂ content from any given district, but tend to increase at any given SiO₂ content from north to south. Th/Ta ratios notably increase with SiO₂, and are lowest in the mid-latitude districts (North Santiam, Detroit Dam, Quartzville, and Blue River). While increased slab fluid could increase Ba relative to Nb, the greater abundance of Ba, Th, and Th/Ta southward at given SiO₂ are more consistent with an increased role of crustal contamination. Dy/Yb ratios decrease with increasing SiO₂ contents with the exception of the North Fork District. V/Sc ratios decrease with increasing SiO₂ with the exception of samples of the Spirit Lake Pluton, and slightly increase from south to north at any given SiO₂ content. Zircons in the Western Cascades plutonic rocks have characteristically large negative Eu anomalies (Eu/Eu* < 0.5) and small positive Ce anomalies, correlated with relatively reduced oxidation states and low water contents, even when directly associated with moderately economic porphyry Cu deposits. Although these magmas are sufficiently water-rich to abundantly crystallize and fractionate amphibole (at least 3 wt. % H₂O), it is evident that plagioclase likely crystallized early and was not suppressed by high water contents (> 3 wt. % H₂O). There is no evidence that Western Cascade magmas were strongly oxidized (> NNO +1). Although crustal thickness is poorly constrained in the north and south segments, it is evidently variable along-arc (and may thicken slightly to the south), but is likely relatively thin. I therefore suggest that crustal thickness and lithology substantially control ore potential within the Western Cascade Arc. Title: Geochemistry of Plutonic Rocks of the Western Cascades, Washington & Oregon : Relationship to Crustal Segmentation and Ore Genesis Author: Utevsky, Elinor S. The volcanic (~45-10 Ma) and plutonic rocks (~37-12 Ma) comprising the Western Cascades extend from northernmost California to southern British Columbia and are ancestral to modern arc magmatism. The ancestral arc hosts a series of small plutons that are locally associated with porphyry (Cu-Mo) and epithermal (Au) ore deposits. Three crustal segments identified by Schmidt et al. (2008, 2013) in the modern arc are potentially reflected in the geochemistry of the ancestral Cascades as well: Paleozoic-Mesozoic accreted terranes, metamorphic rocks, and granites to the north; thin Paleocene Siletzia oceanic crust of the Columbia Embayment in the center; and Paleozoic-Mesozoic ultramafic sheets and marine arc-related volcanic and sedimentary rocks of the Klamath Terrane to the south. Therefore, the Western Cascades of Washington and Oregon provide a field laboratory to examine the chemical compositions and ages of granitoid intrusions associated with a variety of magmatic-hydrothermal ore deposits, and to compare the compositions with the along-arc variation of the age, composition and thickness of the underlying crust. The majority of the 15 new zircon U-Pb ages reported in this study are 27 to 12 Ma with the exception of the ~37 Ma Snoqualmie North Fork intrusions of central WA. A total of 610 zircons were analyzed, of which 118 have ages older than the main population and are considered to be xenocrystic or inherited. The north segment contains the oldest (up to 67 Ma) and most continuous inherited population. The absence of inherited grains older than 67 Ma suggests that neither the North Fork nor White River districts overlie old crystalline crust, but instead overlie Paleocene-Eocene volcanics that are the likely source of inherited zircons. Districts of the Columbia segment have sparse inherited zircon populations (n = 38 of 350 total), ranging from 54 to 20 Ma. The dearth of inherited zircons in the center of the arc suggests limited contamination by a source no older than 55 Ma, likely the dominant Eocene sources of detrital zircon found within the Tyee Formation. Districts overlying the Klamath Terrane have slightly more substantial inherited zircon populations than districts overlying Siletzia but still decidedly few inherited grains (a total of 25 out of 85 grains analyzed, ranging from 44 to 19 Ma); these grains are likely sourced from similar contaminants to those underlying the central segment of the arc, instead of from accreted Mesozoic rocks of the Klamath Terrane. The hypabyssal plutonic rocks represent a small area (~1%) of exposures in the Western Cascades, and range in composition from diorites to granodiorites and minor granite. Fe-Ti oxides, where preserved, include magnetite and ilmenite in proportion of ~2:1, and together with presence of hornblende and biotite are suggestive of modest oxidation states of ~ ΔNNO of 0 to 1 (Carmichael & Nicholls, 1967). Abundant hornblende is observed in 31 of 36 available petrographic sections. Ba/Nb values are not obviously correlated with SiO₂ content from any given district, but tend to increase at any given SiO₂ content from north to south. Th/Ta ratios notably increase with SiO₂, and are lowest in the mid-latitude districts (North Santiam, Detroit Dam, Quartzville, and Blue River). While increased slab fluid could increase Ba relative to Nb, the greater abundance of Ba, Th, and Th/Ta southward at given SiO₂ are more consistent with an increased role of crustal contamination. Dy/Yb ratios decrease with increasing SiO₂ contents with the exception of the North Fork District. V/Sc ratios decrease with increasing SiO₂ with the exception of samples of the Spirit Lake Pluton, and slightly increase from south to north at any given SiO₂ content. Zircons in the Western Cascades plutonic rocks have characteristically large negative Eu anomalies (Eu/Eu* < 0.5) and small positive Ce anomalies, correlated with relatively reduced oxidation states and low water contents, even when directly associated with moderately economic porphyry Cu deposits. Although these magmas are sufficiently water-rich to abundantly crystallize and fractionate amphibole (at least 3 wt. % H₂O), it is evident that plagioclase likely crystallized early and was not suppressed by high water contents (> 3 wt. % H₂O). There is no evidence that Western Cascade magmas were strongly oxidized (> NNO +1). Although crustal thickness is poorly constrained in the north and south segments, it is evidently variable along-arc (and may thicken slightly to the south), but is likely relatively thin. I therefore suggest that crustal thickness and lithology substantially control ore potential within the Western Cascade Arc. Close

• 2818. [Article] Adaptive Multiagent Traffic Management for Autonomous Robotic Systems

  There is growing commercial interest in the use of unmanned aerial vehicles (UAVs) in urban environments, specifically for package delivery applications. However, the size, complexity and sheer numbers ...

  Citation × Citation Citation Abstract Copy Title: Adaptive Multiagent Traffic Management for Autonomous Robotic Systems Author: Rebhuhn, Carrie There is growing commercial interest in the use of unmanned aerial vehicles (UAVs) in urban environments, specifically for package delivery applications. However, the size, complexity and sheer numbers of expected UAVs makes conventional air traffic management that relies on human air traffic controllers infeasible. To enable UAVs to safely and efficiently operate in congested environments, it is essential to develop autonomous UAV management strategies. We introduce a dynamic hierarchical traffic control model that reacts to traffic conditions instantaneously to reduce congestion in the airspace. An obstacle-filled airspace lends itself to a modelling as a graph structure similar to a road network. We introduce controller agents, which set costs across the airspace. These agents control traffic similarly to adaptive metering lights in highway traffic. UAVs then plan their paths based on the costs (e.g. conflicts, or delays) they see for traversing particular parts of the airspace. This provides us a decentralized method for reducing traffic in an airspace Our hierarchical structure allows us to separate the traffic reduction problem from the individual robot navigation problem. Each robot does not explicitly coordinate with others in the airspace. Instead, robots execute their own individual internal cost-based planner to travel between locations. We then use neuro-evolution to provide incentives to these cost-based planners to reduce traffic in the environment. Traffic quality can be expressed in several different ways. We first evaluate traffic our traffic reduction policies in terms of `conflicts', which characterizes situations where an aircraft comes too close to another for safety in a physical space. We then examine traffic in terms of the amount of `delay' that all agents incur, which assumes that there is a structure to ensure only a safe number of UAVs occupy the same area. Finally, we look at the total travel time that a UAV can expect to take from the moment it enters the airspace until the time it gets to its destination. To facilitate an exploration of the UTM problem without waiting for a full simulation of UAVS running with A* , we develop an abstraction of the UTM domain that preserves the core UTM problem. We then investigate performance under differing levels of traffic, a well as two different agent structures. Our results show similar performance for both agent definitions, with delay reduction of up to 68% in high traffic cases. With a fast version of the UTM problem, we explore the effect of redefining the control structure such that links, or edges of the UTM graph, set costs individually. This shifts the control paradigm toward controlling directional travel rather than areas in the space, as was the case with sector agents used in previous approaches. Due to our graph structure, we find that there are far more control elements in the link agent approach than in the sector agent approach. We identify a tradeoff; link agents give finer control, but the coordination problem for the sector agents is easier because there are fewer sector agents. This indicates that we can improve performance out of a more distributed link-based setup if we address the challenges of multiagent coordination. However, the UAV traffic management domain presents a uniquely difficult coordination problem; each agent's action can affect the perceived value of every other agent's actions. This means that there is an excessive amount of noise in the system, as another agent's action can have a lot of impact on the reward an agent receives. We reduce the amount of multiagent noise by reducing the number of agents that are capable of learning. We identify that some agents have more ability to influence traffic based on the topology and traffic profile of the graph. This metric we call impactfulness. We use this metric to improve the learning by removing less impactful agents from the learning process, making a more stationary system in which the impactful agents can learn. The contributions of this work are to: - Introduce a cost-based traffic management approach that is platform-agnostic and fast to implement. - Develop a multiagent approach to setting costs in this traffic management system that is adaptive to traffic conditions and learns long-term effects of management decisions. - Create an abstraction of UAV traffic that captures key physical attributes, creating a fast and flexible simulation method. - Quantify agent contributions to system performance by experimenting with single agent learning, single agent exclusion, and a sliding number of agents learning in the system. Title: Adaptive Multiagent Traffic Management for Autonomous Robotic Systems Author: Rebhuhn, Carrie There is growing commercial interest in the use of unmanned aerial vehicles (UAVs) in urban environments, specifically for package delivery applications. However, the size, complexity and sheer numbers of expected UAVs makes conventional air traffic management that relies on human air traffic controllers infeasible. To enable UAVs to safely and efficiently operate in congested environments, it is essential to develop autonomous UAV management strategies. We introduce a dynamic hierarchical traffic control model that reacts to traffic conditions instantaneously to reduce congestion in the airspace. An obstacle-filled airspace lends itself to a modelling as a graph structure similar to a road network. We introduce controller agents, which set costs across the airspace. These agents control traffic similarly to adaptive metering lights in highway traffic. UAVs then plan their paths based on the costs (e.g. conflicts, or delays) they see for traversing particular parts of the airspace. This provides us a decentralized method for reducing traffic in an airspace Our hierarchical structure allows us to separate the traffic reduction problem from the individual robot navigation problem. Each robot does not explicitly coordinate with others in the airspace. Instead, robots execute their own individual internal cost-based planner to travel between locations. We then use neuro-evolution to provide incentives to these cost-based planners to reduce traffic in the environment. Traffic quality can be expressed in several different ways. We first evaluate traffic our traffic reduction policies in terms of `conflicts', which characterizes situations where an aircraft comes too close to another for safety in a physical space. We then examine traffic in terms of the amount of `delay' that all agents incur, which assumes that there is a structure to ensure only a safe number of UAVs occupy the same area. Finally, we look at the total travel time that a UAV can expect to take from the moment it enters the airspace until the time it gets to its destination. To facilitate an exploration of the UTM problem without waiting for a full simulation of UAVS running with A* , we develop an abstraction of the UTM domain that preserves the core UTM problem. We then investigate performance under differing levels of traffic, a well as two different agent structures. Our results show similar performance for both agent definitions, with delay reduction of up to 68% in high traffic cases. With a fast version of the UTM problem, we explore the effect of redefining the control structure such that links, or edges of the UTM graph, set costs individually. This shifts the control paradigm toward controlling directional travel rather than areas in the space, as was the case with sector agents used in previous approaches. Due to our graph structure, we find that there are far more control elements in the link agent approach than in the sector agent approach. We identify a tradeoff; link agents give finer control, but the coordination problem for the sector agents is easier because there are fewer sector agents. This indicates that we can improve performance out of a more distributed link-based setup if we address the challenges of multiagent coordination. However, the UAV traffic management domain presents a uniquely difficult coordination problem; each agent's action can affect the perceived value of every other agent's actions. This means that there is an excessive amount of noise in the system, as another agent's action can have a lot of impact on the reward an agent receives. We reduce the amount of multiagent noise by reducing the number of agents that are capable of learning. We identify that some agents have more ability to influence traffic based on the topology and traffic profile of the graph. This metric we call impactfulness. We use this metric to improve the learning by removing less impactful agents from the learning process, making a more stationary system in which the impactful agents can learn. The contributions of this work are to: - Introduce a cost-based traffic management approach that is platform-agnostic and fast to implement. - Develop a multiagent approach to setting costs in this traffic management system that is adaptive to traffic conditions and learns long-term effects of management decisions. - Create an abstraction of UAV traffic that captures key physical attributes, creating a fast and flexible simulation method. - Quantify agent contributions to system performance by experimenting with single agent learning, single agent exclusion, and a sliding number of agents learning in the system. Close

• 2819. [Image] Water temperature monitoring of the Klamath River mainstem: final report

  	WATER TEMPERATURE MONITORING KLAMATH RIVER MAINSTEM ABSTRACT This report summarizes the water temperature data collected by the Karuk Tribe of California (Karuk Tribe) from July 1993 to September 1997 ...
  	Citation × Citation Citation Abstract Copy Title: Water temperature monitoring of the Klamath River mainstem: final report Author: Karuk Tribe of California Year: 1999, 2005 WATER TEMPERATURE MONITORING KLAMATH RIVER MAINSTEM ABSTRACT This report summarizes the water temperature data collected by the Karuk Tribe of California (Karuk Tribe) from July 1993 to September 1997 at thirteen locations along the Klamath River from Upper Klamath Lake to the mouth of the Klamath River at the Pacific Ocean. This report describes the water temperature monitoring system designed by the Karuk Tribe, the data checks that were performed, and a summary of the water temperature data results. The Karuk Tribe began this study in part in response to the Klamath River Basin Fisheries Task Force stated objective to monitor water temperature conditions above, within, and below existing water projects along the Klamath River. With help from the California Department of Fish and Game, PacifiCorp, and the Klamath National Forest, this project was expanded from six to thirteen original monitoring sites in 1993. Water temperature data were collected by Ryan TempMentor? instruments typically on an hourly time interval. The data was checked for accuracy by consultants and reduced for this report to mean daily water temperature values each year on a monthly basis in US Geological Survey tabular format. Mean value data were entered into a Microsoft Access relational database for use on an IBM compatible computer. Although the period of record for the Klamath River water temperature data stretches over 5 years, several gaps in data inhibit detailed analysis. The analysis presented, illustrates when the minimum and maximum preferred temperature ranges for salmonids are exceeded. In addition, preliminary temperature trend shows that in August water temperature values below Iron Gate Dam were lower than other monitoring stations further downstream. Conversely, water temperature values in October are warmer below Iron Gate than in the unregulated reaches of the Klamath River downstream. Given this information, it appears that releases from Iron Gate Dam do influence the natural water temperature balance in the Klamath River. To more accurately determine the extent of reservoir releases on the natural thermal environment, additional water temperature measurements need to be collected. Title: Water temperature monitoring of the Klamath River mainstem: final report Author: Karuk Tribe of California Year: 1999, 2005 WATER TEMPERATURE MONITORING KLAMATH RIVER MAINSTEM ABSTRACT This report summarizes the water temperature data collected by the Karuk Tribe of California (Karuk Tribe) from July 1993 to September 1997 at thirteen locations along the Klamath River from Upper Klamath Lake to the mouth of the Klamath River at the Pacific Ocean. This report describes the water temperature monitoring system designed by the Karuk Tribe, the data checks that were performed, and a summary of the water temperature data results. The Karuk Tribe began this study in part in response to the Klamath River Basin Fisheries Task Force stated objective to monitor water temperature conditions above, within, and below existing water projects along the Klamath River. With help from the California Department of Fish and Game, PacifiCorp, and the Klamath National Forest, this project was expanded from six to thirteen original monitoring sites in 1993. Water temperature data were collected by Ryan TempMentor? instruments typically on an hourly time interval. The data was checked for accuracy by consultants and reduced for this report to mean daily water temperature values each year on a monthly basis in US Geological Survey tabular format. Mean value data were entered into a Microsoft Access relational database for use on an IBM compatible computer. Although the period of record for the Klamath River water temperature data stretches over 5 years, several gaps in data inhibit detailed analysis. The analysis presented, illustrates when the minimum and maximum preferred temperature ranges for salmonids are exceeded. In addition, preliminary temperature trend shows that in August water temperature values below Iron Gate Dam were lower than other monitoring stations further downstream. Conversely, water temperature values in October are warmer below Iron Gate than in the unregulated reaches of the Klamath River downstream. Given this information, it appears that releases from Iron Gate Dam do influence the natural water temperature balance in the Klamath River. To more accurately determine the extent of reservoir releases on the natural thermal environment, additional water temperature measurements need to be collected. Close

• 2820. [Image] Weather based technologies for residential irrigation scheduling: technical review report: prepared for Municipal Water District

  	"May 2004"
  	Citation × Citation Citation Abstract Copy Title: Weather based technologies for residential irrigation scheduling: technical review report: prepared for Municipal Water District Year: 2004, 2005 "May 2004" Title: Weather based technologies for residential irrigation scheduling: technical review report: prepared for Municipal Water District Year: 2004, 2005 "May 2004" Close