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• 1. [Article] How Will Climate Change and Bioenergy Harvest Affect Carbon Storage in the Oregon Coast Range

  This poster shows how the researchers used a simulation model to explore the impacts of varying scenarios of climate change and forest management on the ecosystem carbon.

  Citation × Citation Citation Abstract Copy Title: How Will Climate Change and Bioenergy Harvest Affect Carbon Storage in the Oregon Coast Range Author: Creutzburg, Megan K., Scheller, Robert M., Lucash, Melissa S., LeDuc, Stephen D., Evers, Louisa B., Johnson, Mark G. Year: 2014 This poster shows how the researchers used a simulation model to explore the impacts of varying scenarios of climate change and forest management on the ecosystem carbon. Title: How Will Climate Change and Bioenergy Harvest Affect Carbon Storage in the Oregon Coast Range Author: Creutzburg, Megan K., Scheller, Robert M., Lucash, Melissa S., LeDuc, Stephen D., Evers, Louisa B., Johnson, Mark G. Year: 2014 This poster shows how the researchers used a simulation model to explore the impacts of varying scenarios of climate change and forest management on the ecosystem carbon. Close

• 2. [Article] Internal Temperature of Douglas-Fir Buds is Altered at Elevated Temperature

  Pseudotsuga menziesii (Douglas-fir) saplings were grown in sun-lit controlled environment chambers at ambient or elevated (4°C above ambient) temperature. We measured internal temperatures of vegetative ...

  Citation × Citation Citation Abstract Copy Title: Internal Temperature of Douglas-Fir Buds is Altered at Elevated Temperature Author: Apple, Martha E., Lucash, Melissa S., Olszyk, David M., Tingey, David T., Phillips, Donald L. Year: 1999 Pseudotsuga menziesii (Douglas-fir) saplings were grown in sun-lit controlled environment chambers at ambient or elevated (4°C above ambient) temperature. We measured internal temperatures of vegetative buds with thermocouple probes and compared temperatures of normal buds and abnormal buds with loosened, rosetted outer scales in elevated temperature chambers. The abnormal buds had higher and earlier peak daily temperatures than normal buds. Elevated temperature may influence the internal temperature of buds and contribute to the development of abnormal, rosetted buds with loosened outer scales. Abnormal bud development may alter branching patterns and allometry of Douglas-fir trees subjected to climatic change. Title: Internal Temperature of Douglas-Fir Buds is Altered at Elevated Temperature Author: Apple, Martha E., Lucash, Melissa S., Olszyk, David M., Tingey, David T., Phillips, Donald L. Year: 1999 Pseudotsuga menziesii (Douglas-fir) saplings were grown in sun-lit controlled environment chambers at ambient or elevated (4°C above ambient) temperature. We measured internal temperatures of vegetative buds with thermocouple probes and compared temperatures of normal buds and abnormal buds with loosened, rosetted outer scales in elevated temperature chambers. The abnormal buds had higher and earlier peak daily temperatures than normal buds. Elevated temperature may influence the internal temperature of buds and contribute to the development of abnormal, rosetted buds with loosened outer scales. Abnormal bud development may alter branching patterns and allometry of Douglas-fir trees subjected to climatic change. Close

• 3. [Article] Response of Sagebrush Steppe Species to Elevated CO2 and Soil Temperature

  Elevated atmospheric CO2 may cause long-term changes in the productivity and species composition of the sagebrush steppe. Few studies, however, have evaluated the effects of increased CO2 on growth and ...

  Citation × Citation Citation Abstract Copy Title: Response of Sagebrush Steppe Species to Elevated CO2 and Soil Temperature Author: Lucash, Melissa S., Farnsworth, Blake, Winner, William E. Year: 2005 Elevated atmospheric CO2 may cause long-term changes in the productivity and species composition of the sagebrush steppe. Few studies, however, have evaluated the effects of increased CO2 on growth and physiology of species important to this ecosystem. Since the response of plants to elevated CO2 may be limited by environmental factors, soil temperature was also examined to determine if low soil temperatures limit CO2 response. To determine how CO2 and soil temperature affect the growth of species native to the sagebrush steppe, bottlebrush squirreltail [Elymus elymoides (Raf.) Swezey], Thurber needlegrass (Stipa thurberiana Piper), and Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle) were grown in ambient (374 mL L–1) or high (567 mL L–1) CO2 and low (13°C) or high (18°C) soil temperature for approximately 4 months. Although soil temperature affected the growth of squirreltail and needlegrass, temperature did not modify their response to elevated CO2. Total biomass of sagebrush was consistent across soil temperature and CO2 treatments, reflecting its slow-growing strategy. All 3 species had higher leaf water-use efficiency at elevated CO2 due to higher net photosynthesis and lower transpiration rates. We conclude that elevated CO2 and soil warming may increase the growth of grasses more than shrubs. Field studies in the sagebrush steppe are necessary to determine if differences in biomass, resulting from changes in CO2 and soil temperature, are exhibited in the field. Title: Response of Sagebrush Steppe Species to Elevated CO2 and Soil Temperature Author: Lucash, Melissa S., Farnsworth, Blake, Winner, William E. Year: 2005 Elevated atmospheric CO2 may cause long-term changes in the productivity and species composition of the sagebrush steppe. Few studies, however, have evaluated the effects of increased CO2 on growth and physiology of species important to this ecosystem. Since the response of plants to elevated CO2 may be limited by environmental factors, soil temperature was also examined to determine if low soil temperatures limit CO2 response. To determine how CO2 and soil temperature affect the growth of species native to the sagebrush steppe, bottlebrush squirreltail [Elymus elymoides (Raf.) Swezey], Thurber needlegrass (Stipa thurberiana Piper), and Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle) were grown in ambient (374 mL L–1) or high (567 mL L–1) CO2 and low (13°C) or high (18°C) soil temperature for approximately 4 months. Although soil temperature affected the growth of squirreltail and needlegrass, temperature did not modify their response to elevated CO2. Total biomass of sagebrush was consistent across soil temperature and CO2 treatments, reflecting its slow-growing strategy. All 3 species had higher leaf water-use efficiency at elevated CO2 due to higher net photosynthesis and lower transpiration rates. We conclude that elevated CO2 and soil warming may increase the growth of grasses more than shrubs. Field studies in the sagebrush steppe are necessary to determine if differences in biomass, resulting from changes in CO2 and soil temperature, are exhibited in the field. Close

• 4. [Article] Relationships Between Needle Nitrogen Concentration and Photosynthetic Responses of Douglas-Fir Seedlings to Elevated CO2 and Temperature

  Here we examined correlations between needle nitrogen concentration ([N]) and photosynthetic responses of Douglas-fir (Pseudotsuga menziesii) seedlings to growth in elevated temperatures and atmospheric ...

  Citation × Citation Citation Abstract Copy Title: Relationships Between Needle Nitrogen Concentration and Photosynthetic Responses of Douglas-Fir Seedlings to Elevated CO2 and Temperature Author: Lewis, James D., Lucash, Melissa S., Olszyk, David M., Tingey, David T. Year: 2004 Here we examined correlations between needle nitrogen concentration ([N]) and photosynthetic responses of Douglas-fir (Pseudotsuga menziesii) seedlings to growth in elevated temperatures and atmospheric carbon dioxide concentrations ([CO2]). Seedlings were grown in sunlit, climate-controlled chambers at ambient or ambient+3.5° C and ambient or ambient +180 μmol mol-1 CO2 in a full factorial design. Photosynthetic parameters and needle [N] were measured six times over a 21-month period. Needle [N] varied seasonally, and accounted for 30–50% of the variation in photosynthetic parameters. Across measurement periods, elevated temperature increased needle [N] by 26% and light-saturated net photosynthetic rates by 17%. Elevated [CO2] decreased needle [N] by 12%, and reduced net photosynthetic rates measured at a common [CO2], maximum carboxylation activity (Vc,max) and electrontransport capacity (Jmax), indicating photosynthetic acclimatization. Even so, elevated [CO2] enhanced net photosynthesis, and this effect increased with needle [N]. These results suggest that needle [N] may regulate photosynthetic responses of Douglas-fir to climate change. Further, needle [N] may be altered by climate change. However, effects of elevated [CO2] on photosynthesis may be similar across growth temperatures. Title: Relationships Between Needle Nitrogen Concentration and Photosynthetic Responses of Douglas-Fir Seedlings to Elevated CO2 and Temperature Author: Lewis, James D., Lucash, Melissa S., Olszyk, David M., Tingey, David T. Year: 2004 Here we examined correlations between needle nitrogen concentration ([N]) and photosynthetic responses of Douglas-fir (Pseudotsuga menziesii) seedlings to growth in elevated temperatures and atmospheric carbon dioxide concentrations ([CO2]). Seedlings were grown in sunlit, climate-controlled chambers at ambient or ambient+3.5° C and ambient or ambient +180 μmol mol-1 CO2 in a full factorial design. Photosynthetic parameters and needle [N] were measured six times over a 21-month period. Needle [N] varied seasonally, and accounted for 30–50% of the variation in photosynthetic parameters. Across measurement periods, elevated temperature increased needle [N] by 26% and light-saturated net photosynthetic rates by 17%. Elevated [CO2] decreased needle [N] by 12%, and reduced net photosynthetic rates measured at a common [CO2], maximum carboxylation activity (Vc,max) and electrontransport capacity (Jmax), indicating photosynthetic acclimatization. Even so, elevated [CO2] enhanced net photosynthesis, and this effect increased with needle [N]. These results suggest that needle [N] may regulate photosynthetic responses of Douglas-fir to climate change. Further, needle [N] may be altered by climate change. However, effects of elevated [CO2] on photosynthesis may be similar across growth temperatures. Close

• 5. [Article] Stomatal Responses of Douglas-Fir Seedlings to Elevated Carbon Dioxide and Temperature During the Third and Fourth Years of Exposure

  Two major components of climate change, increasing atmospheric [CO2] and increasing temperature, may substantially alter the effects of water availability to plants through effects on the rate of water ...

  Citation × Citation Citation Abstract Copy Title: Stomatal Responses of Douglas-Fir Seedlings to Elevated Carbon Dioxide and Temperature During the Third and Fourth Years of Exposure Author: Lewis, James D., Lucash, Melissa S., Olszyk, David M., Tingey, David T. Year: 2002 Two major components of climate change, increasing atmospheric [CO2] and increasing temperature, may substantially alter the effects of water availability to plants through effects on the rate of water loss from leaves. We examined the interactive effects of elevated [CO2] and temperature on seasonal patterns of stomatal conductance (gs), transpiration (E) and instantaneous transpiration efficiency (ITE) in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings. Seedlings were grown in sunlit chambers at either ambient CO2 (AC) or ambient + 180 µmol mol-1 CO2 (EC), and at ambient temperature (AT) or ambient + 3.5° C (ET) in a full-factorial design. Needle gas exchange at the target growth conditions was measured approximately monthly over 21 months. Across the study period and across temperature treatments, growth in elevated [CO2] decreased E by an average of 12% and increased ITE by an average of 46%. The absolute reduction of E associated with elevated [CO2] significantly increased with seasonal increases in the needle-to-air vapour pressure deficit (D). Across CO2 treatments, growth in elevated temperature increased E an average of 37%, and did not affect ITE. Combined, growth in elevated [CO2] and elevated temperature increased E an average of 19% compared with the ACAT treatment. The CO2 supply and growth temperature did not significantly affect stomatal sensitivity to D or the relationship between gs and net photosynthetic rates. This study suggests that elevated [CO2] may not completely ameliorate the effect of elevated temperature on E, and that climate change may substantially alter needle-level water loss and water use efficiency of Douglas-fir seedlings. Title: Stomatal Responses of Douglas-Fir Seedlings to Elevated Carbon Dioxide and Temperature During the Third and Fourth Years of Exposure Author: Lewis, James D., Lucash, Melissa S., Olszyk, David M., Tingey, David T. Year: 2002 Two major components of climate change, increasing atmospheric [CO2] and increasing temperature, may substantially alter the effects of water availability to plants through effects on the rate of water loss from leaves. We examined the interactive effects of elevated [CO2] and temperature on seasonal patterns of stomatal conductance (gs), transpiration (E) and instantaneous transpiration efficiency (ITE) in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings. Seedlings were grown in sunlit chambers at either ambient CO2 (AC) or ambient + 180 µmol mol-1 CO2 (EC), and at ambient temperature (AT) or ambient + 3.5° C (ET) in a full-factorial design. Needle gas exchange at the target growth conditions was measured approximately monthly over 21 months. Across the study period and across temperature treatments, growth in elevated [CO2] decreased E by an average of 12% and increased ITE by an average of 46%. The absolute reduction of E associated with elevated [CO2] significantly increased with seasonal increases in the needle-to-air vapour pressure deficit (D). Across CO2 treatments, growth in elevated temperature increased E an average of 37%, and did not affect ITE. Combined, growth in elevated [CO2] and elevated temperature increased E an average of 19% compared with the ACAT treatment. The CO2 supply and growth temperature did not significantly affect stomatal sensitivity to D or the relationship between gs and net photosynthetic rates. This study suggests that elevated [CO2] may not completely ameliorate the effect of elevated temperature on E, and that climate change may substantially alter needle-level water loss and water use efficiency of Douglas-fir seedlings. Close

• 6. [Article] Seasonal Patterns of Photosynthesis in Douglas Fir Seedlings During the Third and Fourth Year of Exposure to Elevated CO2 and Temperature

  The interactive effects of elevated atmospheric CO2 and temperature on seasonal patterns of photosynthesis in Douglas fir (Psuedotsuga menziesii (Mirb.) Franco) seedlings were examined. Seedlings were ...

  Citation × Citation Citation Abstract Copy Title: Seasonal Patterns of Photosynthesis in Douglas Fir Seedlings During the Third and Fourth Year of Exposure to Elevated CO2 and Temperature Author: Lewis, James D., Lucash, Melissa S., Olszyk, David M., Tingey, David T. Year: 2001 The interactive effects of elevated atmospheric CO2 and temperature on seasonal patterns of photosynthesis in Douglas fir (Psuedotsuga menziesii (Mirb.) Franco) seedlings were examined. Seedlings were grown in sunlit chambers controlled to track either ambient (~400 p.p.m.) CO2 or ambient +200 p.p.m. CO2, and either ambient temperature or ambient +4 °C. Light-saturated net photosynthetic rates were measured approximately monthly over a 21 month period. Elevated CO2 increased net photosynthetic rates by an average of 21% across temperature treatments during both the 1996 hydrologic year, the third year of exposure, and the 1997 hydrologic year. Elevated mean annual temperature increased net photosynthetic rates by an average of 33% across CO2 treatments during both years. Seasonal temperature changes also affected net photosynthetic rates. Across treatments, net photosynthetic rates were highest in the spring and autumn, and lowest in July, August and December–January. Seasonal increases in temperature were not correlated with increases in the relative photosynthetic response to elevated CO2. Seasonal shifts in the photosynthetic temperature optimum reduced temperature effects on the relative response to elevated CO2. These results suggest that the effects of elevated CO2 on net photosynthetic rates in Douglas fir are largely independent of temperature. Title: Seasonal Patterns of Photosynthesis in Douglas Fir Seedlings During the Third and Fourth Year of Exposure to Elevated CO2 and Temperature Author: Lewis, James D., Lucash, Melissa S., Olszyk, David M., Tingey, David T. Year: 2001 The interactive effects of elevated atmospheric CO2 and temperature on seasonal patterns of photosynthesis in Douglas fir (Psuedotsuga menziesii (Mirb.) Franco) seedlings were examined. Seedlings were grown in sunlit chambers controlled to track either ambient (~400 p.p.m.) CO2 or ambient +200 p.p.m. CO2, and either ambient temperature or ambient +4 °C. Light-saturated net photosynthetic rates were measured approximately monthly over a 21 month period. Elevated CO2 increased net photosynthetic rates by an average of 21% across temperature treatments during both the 1996 hydrologic year, the third year of exposure, and the 1997 hydrologic year. Elevated mean annual temperature increased net photosynthetic rates by an average of 33% across CO2 treatments during both years. Seasonal temperature changes also affected net photosynthetic rates. Across treatments, net photosynthetic rates were highest in the spring and autumn, and lowest in July, August and December–January. Seasonal increases in temperature were not correlated with increases in the relative photosynthetic response to elevated CO2. Seasonal shifts in the photosynthetic temperature optimum reduced temperature effects on the relative response to elevated CO2. These results suggest that the effects of elevated CO2 on net photosynthetic rates in Douglas fir are largely independent of temperature. Close

• 7. [Article] Morphogenesis of Douglas Fir Buds is Altered at Elevated Temperature but not at Elevated CO2

  Global climatic change as expressed by increased CO2 and temperature has the potential for dramatic effects on trees. To determine what its effects may be on Pacific Northwest forests, Douglas-fir (Pseudotsuga ...

  Citation × Citation Citation Abstract Copy Title: Morphogenesis of Douglas Fir Buds is Altered at Elevated Temperature but not at Elevated CO2 Author: Apple, Martha E., Lucash, Melissa S., Olszyk, David M., Tingey, David T. Year: 1998 Global climatic change as expressed by increased CO2 and temperature has the potential for dramatic effects on trees. To determine what its effects may be on Pacific Northwest forests, Douglas-fir (Pseudotsuga menziesii ) seedlings were grown in sun-lit controlled environment chambers at ambient or elevated (+4°C above ambient) temperature, and at ambient or elevated (+200 ppm above ambient) CO2. In 1995–1996 and 1996–1997, elevated CO2 had no effect on vegetative bud morphology, while the following unusual morphological characteristics were found with greater frequency at elevated temperature than at ambient: rosetted buds with reflexed and loosened outer scales, convoluted inner scales, clusters of small buds, needles elongating between scales, needle primordia with white, hyaline apical extensions, and buds with hardened scales inside of unbroken buds. Buds became rosetted in elevated temperature chambers after temperatures exceeded 40°C in July, 1996. Rosettes were induced within 48-h in buds placed in a 40°C oven; fewer rosettes formed at 20°C. Induction was reversible in buds transferred from 40 to 20°C, implying that rosetting is a physical rather than a growth phenomenon. It appears that rosettes form after long-term exposure to elevated temperature and after shorter periods of exposure to intense heat. Elevated temperature influences bud morphology and may therefore influence the overall branching structure of Douglas-fir seedlings. Title: Morphogenesis of Douglas Fir Buds is Altered at Elevated Temperature but not at Elevated CO2 Author: Apple, Martha E., Lucash, Melissa S., Olszyk, David M., Tingey, David T. Year: 1998 Global climatic change as expressed by increased CO2 and temperature has the potential for dramatic effects on trees. To determine what its effects may be on Pacific Northwest forests, Douglas-fir (Pseudotsuga menziesii ) seedlings were grown in sun-lit controlled environment chambers at ambient or elevated (+4°C above ambient) temperature, and at ambient or elevated (+200 ppm above ambient) CO2. In 1995–1996 and 1996–1997, elevated CO2 had no effect on vegetative bud morphology, while the following unusual morphological characteristics were found with greater frequency at elevated temperature than at ambient: rosetted buds with reflexed and loosened outer scales, convoluted inner scales, clusters of small buds, needles elongating between scales, needle primordia with white, hyaline apical extensions, and buds with hardened scales inside of unbroken buds. Buds became rosetted in elevated temperature chambers after temperatures exceeded 40°C in July, 1996. Rosettes were induced within 48-h in buds placed in a 40°C oven; fewer rosettes formed at 20°C. Induction was reversible in buds transferred from 40 to 20°C, implying that rosetting is a physical rather than a growth phenomenon. It appears that rosettes form after long-term exposure to elevated temperature and after shorter periods of exposure to intense heat. Elevated temperature influences bud morphology and may therefore influence the overall branching structure of Douglas-fir seedlings. Close

• 8. [Article] Disequilibrium of Fire-prone Forests Sets the Stage for a Rapid Decline in Conifer Dominance during the 21st Century

  As trees are long-lived organisms, the impacts of climate change on forest communities may not be apparent on the time scale of years to decades. While lagged responses to environmental change are common ...

  Citation × Citation Citation Abstract Copy Title: Disequilibrium of Fire-prone Forests Sets the Stage for a Rapid Decline in Conifer Dominance during the 21st Century Author: Serra-Diaz, Josep M., Maxwell, Charles, Lucash, Melissa S., Scheller, Robert M., Laflower, Danelle M., Miller, Adam D., Tepley, Alan J., Epstein, Howard E., Anderson-Teixeira, Kristina J., Thompson, Jonathan R. Year: 2017 As trees are long-lived organisms, the impacts of climate change on forest communities may not be apparent on the time scale of years to decades. While lagged responses to environmental change are common in forested systems, potential for abrupt transitions under climate change may occur in environments where alternative vegetation states are influenced by disturbances, such as fire. The Klamath mountains (northern California and southwest Oregon, USA) are currently dominated by carbon rich and hyper-diverse temperate conifer forests, but climate change could disrupt the mechanisms promoting forest stability– regeneration and fire tolerance— via shifts in the fire regime in conjunction with lower fitness of conifers under a hotter climate. Understanding how this landscape will respond to near-term climate change (before 2100) is critical for predicting potential climate change feedbacks and to developing sound forest conservation and management plans. Using a landscape simulation model, we estimate that 1/3 of the Klamath could transition from conifer forest to shrub/hardwood chaparral, triggered by an enhanced fire activity coupled with lower post-fire conifer establishment. Such shifts were more prevalent under higher climate change forcing (RCP 8.5) but were also simulated under the climate of 1950-2000, reflecting the joint influences of early warming trends and historical forest legacies. Our results demonstrate that there is a large potential for loss of conifer forest dominance—and associated carbon stocks and biodiversity-- in the Klamath before the end of the century, and that some losses would likely occur even without the influence of climate change. Thus, in the Klamath and other forested landscapes subject to similar feedback dynamics, major ecosystem shifts should be expected when climate change disrupts key stabilizing feedbacks that maintain the dominance of long-lived, slowly regenerating trees. Title: Disequilibrium of Fire-prone Forests Sets the Stage for a Rapid Decline in Conifer Dominance during the 21st Century Author: Serra-Diaz, Josep M., Maxwell, Charles, Lucash, Melissa S., Scheller, Robert M., Laflower, Danelle M., Miller, Adam D., Tepley, Alan J., Epstein, Howard E., Anderson-Teixeira, Kristina J., Thompson, Jonathan R. Year: 2017 As trees are long-lived organisms, the impacts of climate change on forest communities may not be apparent on the time scale of years to decades. While lagged responses to environmental change are common in forested systems, potential for abrupt transitions under climate change may occur in environments where alternative vegetation states are influenced by disturbances, such as fire. The Klamath mountains (northern California and southwest Oregon, USA) are currently dominated by carbon rich and hyper-diverse temperate conifer forests, but climate change could disrupt the mechanisms promoting forest stability– regeneration and fire tolerance— via shifts in the fire regime in conjunction with lower fitness of conifers under a hotter climate. Understanding how this landscape will respond to near-term climate change (before 2100) is critical for predicting potential climate change feedbacks and to developing sound forest conservation and management plans. Using a landscape simulation model, we estimate that 1/3 of the Klamath could transition from conifer forest to shrub/hardwood chaparral, triggered by an enhanced fire activity coupled with lower post-fire conifer establishment. Such shifts were more prevalent under higher climate change forcing (RCP 8.5) but were also simulated under the climate of 1950-2000, reflecting the joint influences of early warming trends and historical forest legacies. Our results demonstrate that there is a large potential for loss of conifer forest dominance—and associated carbon stocks and biodiversity-- in the Klamath before the end of the century, and that some losses would likely occur even without the influence of climate change. Thus, in the Klamath and other forested landscapes subject to similar feedback dynamics, major ecosystem shifts should be expected when climate change disrupts key stabilizing feedbacks that maintain the dominance of long-lived, slowly regenerating trees. Close

• 9. [Article] Divergent Carbon Dynamics under Climate Change in Forests with Diverse Soils, Tree Species, and Land Use Histories

  Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding ...

  Citation × Citation Citation Abstract Copy Title: Divergent Carbon Dynamics under Climate Change in Forests with Diverse Soils, Tree Species, and Land Use Histories Author: Scheller, Robert M., Kretchun, Alec M., Van Tuyl, Steve, Clark, Kenneth L., Lucash, Melissa S., Hom, John Year: 2012 Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding of forest carbon dynamics is, however, challenging in systems characterized by historic over-utilization, diverse soils and tree species, and frequent disturbance. In order to elucidate the cascading effects of potential climate change on such systems, we projected forest carbon dynamics, including soil carbon changes, and shifts in tree species composition as a consequence of wildfires and climate change in the New Jersey pine barrens (NJPB) over the next 100 years. To do so, we used the LANDIS-II succession and disturbance model combined with the CENTURY soil model. The model was calibrated and validated using data from three eddy flux towers and the available empirical or literature data. Our results suggest that climate change will not appreciably increase fire sizes and intensity. The recovery of C stocks following substantial disturbances at the turn of the 20th century will play a limited but important role in this system. In areas characterized by high soil water holding capacity, reduced soil moisture may lead to lower total C and these forests may switch from being carbon sinks to becoming carbon neutral towards the latter part of the 21st century. In contrast, other areas characterized by lower soil water holding capacity and drought tolerant species are projected to experience relatively little change over the next 100 years. Across all soil types, however, the regeneration of many key tree species may decline leading to longer-term (beyond 2100) risks to forest C. These divergent responses were largely a function of the dominant tree species, and their respective temperature and soil moisture tolerances, and soil water holding capacity. In summary, the system is initially C conservative but by the end of the 21st century, there is increasing risk of de-stabilization due to declining growth and regeneration. Title: Divergent Carbon Dynamics under Climate Change in Forests with Diverse Soils, Tree Species, and Land Use Histories Author: Scheller, Robert M., Kretchun, Alec M., Van Tuyl, Steve, Clark, Kenneth L., Lucash, Melissa S., Hom, John Year: 2012 Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding of forest carbon dynamics is, however, challenging in systems characterized by historic over-utilization, diverse soils and tree species, and frequent disturbance. In order to elucidate the cascading effects of potential climate change on such systems, we projected forest carbon dynamics, including soil carbon changes, and shifts in tree species composition as a consequence of wildfires and climate change in the New Jersey pine barrens (NJPB) over the next 100 years. To do so, we used the LANDIS-II succession and disturbance model combined with the CENTURY soil model. The model was calibrated and validated using data from three eddy flux towers and the available empirical or literature data. Our results suggest that climate change will not appreciably increase fire sizes and intensity. The recovery of C stocks following substantial disturbances at the turn of the 20th century will play a limited but important role in this system. In areas characterized by high soil water holding capacity, reduced soil moisture may lead to lower total C and these forests may switch from being carbon sinks to becoming carbon neutral towards the latter part of the 21st century. In contrast, other areas characterized by lower soil water holding capacity and drought tolerant species are projected to experience relatively little change over the next 100 years. Across all soil types, however, the regeneration of many key tree species may decline leading to longer-term (beyond 2100) risks to forest C. These divergent responses were largely a function of the dominant tree species, and their respective temperature and soil moisture tolerances, and soil water holding capacity. In summary, the system is initially C conservative but by the end of the 21st century, there is increasing risk of de-stabilization due to declining growth and regeneration. Close

• 10. [Article] Quantifying Resilience of Multiple Ecosystem Services and Biodiversity in a Temperate Forest Landscape

  Resilience is increasingly being considered as a new paradigm of forest management among scientists, practitioners, and policymakers. However, metrics of resilience to environmental change are lacking. ...

  Citation × Citation Citation Abstract Copy Title: Quantifying Resilience of Multiple Ecosystem Services and Biodiversity in a Temperate Forest Landscape Author: Cantarello, Elena, Newton, Adrian C., Martin, Phillip A., Evans, Paul M., Gosal, Arjan, Lucash, Melissa S. Year: 2017 Resilience is increasingly being considered as a new paradigm of forest management among scientists, practitioners, and policymakers. However, metrics of resilience to environmental change are lacking. Faced with novel disturbances, forests may be able to sustain existing ecosystem services and biodiversity by exhibiting resilience, or alternatively these attributes may undergo either a linear or nonlinear decline. Here we provide a novel quantitative approach for assessing forest resilience that focuses on three components of resilience, namely resistance, recovery, and net change, using a spatially explicit model of forest dynamics. Under the pulse set scenarios, we explored the resilience of nine ecosystem services and four biodiversity measures following a one-off disturbance applied to an increasing percentage of forest area. Under the pulse + press set scenarios, the six disturbance intensities explored during the pulse set were followed by a continuous disturbance. We detected thresholds in net change under pulse + press scenarios for the majority of the ecosystem services and biodiversity measures, which started to decline sharply when disturbance affected >40% of the landscape. Thresholds in net change were not observed under the pulse scenarios, with the exception of timber volume and ground flora species richness. Thresholds were most pronounced for aboveground biomass, timber volume with respect to the ecosystem services, and ectomycorrhizal fungi and ground flora species richness with respect to the biodiversity measures. Synthesis and applications. The approach presented here illustrates how the multidimensionality of stability research in ecology can be addressed and how forest resilience can be estimated in practice. Managers should adopt specific management actions to support each of the three components of resilience separately, as these may respond differently to disturbance. In addition, management interventions aiming to deliver resilience should incorporate an assessment of both pulse and press disturbances to ensure detection of threshold responses to disturbance, so that appropriate management interventions can be identified. Title: Quantifying Resilience of Multiple Ecosystem Services and Biodiversity in a Temperate Forest Landscape Author: Cantarello, Elena, Newton, Adrian C., Martin, Phillip A., Evans, Paul M., Gosal, Arjan, Lucash, Melissa S. Year: 2017 Resilience is increasingly being considered as a new paradigm of forest management among scientists, practitioners, and policymakers. However, metrics of resilience to environmental change are lacking. Faced with novel disturbances, forests may be able to sustain existing ecosystem services and biodiversity by exhibiting resilience, or alternatively these attributes may undergo either a linear or nonlinear decline. Here we provide a novel quantitative approach for assessing forest resilience that focuses on three components of resilience, namely resistance, recovery, and net change, using a spatially explicit model of forest dynamics. Under the pulse set scenarios, we explored the resilience of nine ecosystem services and four biodiversity measures following a one-off disturbance applied to an increasing percentage of forest area. Under the pulse + press set scenarios, the six disturbance intensities explored during the pulse set were followed by a continuous disturbance. We detected thresholds in net change under pulse + press scenarios for the majority of the ecosystem services and biodiversity measures, which started to decline sharply when disturbance affected >40% of the landscape. Thresholds in net change were not observed under the pulse scenarios, with the exception of timber volume and ground flora species richness. Thresholds were most pronounced for aboveground biomass, timber volume with respect to the ecosystem services, and ectomycorrhizal fungi and ground flora species richness with respect to the biodiversity measures. Synthesis and applications. The approach presented here illustrates how the multidimensionality of stability research in ecology can be addressed and how forest resilience can be estimated in practice. Managers should adopt specific management actions to support each of the three components of resilience separately, as these may respond differently to disturbance. In addition, management interventions aiming to deliver resilience should incorporate an assessment of both pulse and press disturbances to ensure detection of threshold responses to disturbance, so that appropriate management interventions can be identified. Close