Ecological applications : a publication of the Ecological Society of America, Jan 21, 2016
Balancing economic, ecological and social values has long been a challenge in the forests of the ... more Balancing economic, ecological and social values has long been a challenge in the forests of the Pacific Northwest, where conflict over timber harvest and old-growth habitat on public lands has been contentious for the past several decades. The Northwest Forest Plan, adopted two decades ago to guide management on federal lands, is currently being revised as the region searches for a balance between sustainable timber yields and habitat for sensitive species. In addition, climate change imposes a high degree of uncertainty on future forest productivity, sustainability of timber harvest, wildfire risk, and species habitat. We evaluated the long-term, landscape-scale tradeoffs among carbon (C) storage, timber yield, and old forest habitat given projected climate change and shifts in forest management policy across 2.1 million hectares of forests in the Oregon Coast Range. Projections highlight the divergence between private and public lands under business-as-usual forest management, wh...
Bulletin of The Ecological Society of America, 1995
This study tests the potential for interactions between root-zone temperature and COâ for plants ... more This study tests the potential for interactions between root-zone temperature and COâ for plants which co-occur in a habitat where root-zone temperature fluctuate throughout the day. Controlled environment studies were conducted to expose desert plants to combinations of low or high root zone temperatures and low or high COâ. Artemisia tridentata, Sitanion hystrix, and Stipa thurberiana were chosen for study
Background/Question/Methods The complex interactions among disturbances under a changing climate ... more Background/Question/Methods The complex interactions among disturbances under a changing climate are difficult to disentangle, especially given their dynamic nature. To improve our understanding of how windstorms and climate change may affect carbon cycling, we are using a forest landscape disturbance and succession model (LANDIS-II, Century extension) to project carbon sequestration in northern Minnesota under multiple climate change and disturbance scenarios. The model was calibrated and validated using empirical estimates of aboveground productivity (ANPP) and net ecosystem exchange. Results/Conclusions Our preliminary simulations suggest that climate change will have a much greater impact on C sequestration than windstorms. Climate change lowered C sequestration by 20%, whereas wind reduced sink strength by only 13%. Under the GFDL A1FI climate scenario, windstorms initially lowered C sequestration but by year 2050, wind actually increased C sequestration through higher ANPP. Ou...
Background/Question/Methods Forests are a major component of the global carbon cycle, and scienti... more Background/Question/Methods Forests are a major component of the global carbon cycle, and scientists and managers are exploring the use of forest management options for climate change mitigation. In the highly productive forests of the Oregon Coast Range, climate change mitigation could take the form of different management strategies, including restricting harvest to maximize ecosystem carbon sequestration, or removing forest residue along with harvesting as a source of renewable woody biomass energy. However, the long-term consequences of bioenergy harvesting are unknown, particularly as Coast Range forests face novel conditions resulting from climate change. We used the LANDIS-II forest simulation model to project the impacts of climate change and management actions on above- and below-ground carbon and nitrogen dynamics in a small watershed in the northeastern Oregon Coast Range. We explored scenarios varying in future climatic conditions (including current climate and six scena...
ABSTRACT Root biomass, root production and lifespan, and root-mycorrhizal interactions govern soi... more ABSTRACT Root biomass, root production and lifespan, and root-mycorrhizal interactions govern soil carbon fluxes and resource uptake and are critical components of terrestrial models. However, limitations in data and confusions over terminology, together with a strong dependence on a small set of conceptual frameworks, have limited the exploration of root function in terrestrial models. We review the key root processes of interest to both field ecologists and modelers including root classification, production, turnover, biomass, resource uptake, and depth distribution to ask (1) what are contemporary approaches for modeling roots in terrestrial models? and (2) can these approaches be improved via recent advancements in field research methods? We isolate several emerging themes that are ready for collaboration among field scientists and modelers: (1) alternatives to size-class based root classifications based on function and the inclusion of fungal symbioses, (2) dynamic root allocation and phenology as a function of root environment, rather than leaf demand alone, (3) improved understanding of the treatment of root turnover in models, including the role of root tissue chemistry on root lifespan, (4) better estimates of root stocks across sites and species to parameterize or validate models, and (5) dynamic interplay among rooting depth, resource availability and resource uptake. Greater attention to model parameterization and structural representation of roots will lead to greater appreciation for belowground processes in terrestrial models and improve estimates of ecosystem resilience to global change drivers.
... Apatite, a ubiquitous but trace mineral in parent material, has been shown to be disproportio... more ... Apatite, a ubiquitous but trace mineral in parent material, has been shown to be disproportionately impor-tant as a source of Ca and P in young soils, because of its high weathering rate Melissa S. Lucash Dep. of Environmental Science and Management Portland State Univ. ...
Ecological applications : a publication of the Ecological Society of America, Jan 21, 2016
Balancing economic, ecological and social values has long been a challenge in the forests of the ... more Balancing economic, ecological and social values has long been a challenge in the forests of the Pacific Northwest, where conflict over timber harvest and old-growth habitat on public lands has been contentious for the past several decades. The Northwest Forest Plan, adopted two decades ago to guide management on federal lands, is currently being revised as the region searches for a balance between sustainable timber yields and habitat for sensitive species. In addition, climate change imposes a high degree of uncertainty on future forest productivity, sustainability of timber harvest, wildfire risk, and species habitat. We evaluated the long-term, landscape-scale tradeoffs among carbon (C) storage, timber yield, and old forest habitat given projected climate change and shifts in forest management policy across 2.1 million hectares of forests in the Oregon Coast Range. Projections highlight the divergence between private and public lands under business-as-usual forest management, wh...
Bulletin of The Ecological Society of America, 1995
This study tests the potential for interactions between root-zone temperature and COâ for plants ... more This study tests the potential for interactions between root-zone temperature and COâ for plants which co-occur in a habitat where root-zone temperature fluctuate throughout the day. Controlled environment studies were conducted to expose desert plants to combinations of low or high root zone temperatures and low or high COâ. Artemisia tridentata, Sitanion hystrix, and Stipa thurberiana were chosen for study
Background/Question/Methods The complex interactions among disturbances under a changing climate ... more Background/Question/Methods The complex interactions among disturbances under a changing climate are difficult to disentangle, especially given their dynamic nature. To improve our understanding of how windstorms and climate change may affect carbon cycling, we are using a forest landscape disturbance and succession model (LANDIS-II, Century extension) to project carbon sequestration in northern Minnesota under multiple climate change and disturbance scenarios. The model was calibrated and validated using empirical estimates of aboveground productivity (ANPP) and net ecosystem exchange. Results/Conclusions Our preliminary simulations suggest that climate change will have a much greater impact on C sequestration than windstorms. Climate change lowered C sequestration by 20%, whereas wind reduced sink strength by only 13%. Under the GFDL A1FI climate scenario, windstorms initially lowered C sequestration but by year 2050, wind actually increased C sequestration through higher ANPP. Ou...
Background/Question/Methods Forests are a major component of the global carbon cycle, and scienti... more Background/Question/Methods Forests are a major component of the global carbon cycle, and scientists and managers are exploring the use of forest management options for climate change mitigation. In the highly productive forests of the Oregon Coast Range, climate change mitigation could take the form of different management strategies, including restricting harvest to maximize ecosystem carbon sequestration, or removing forest residue along with harvesting as a source of renewable woody biomass energy. However, the long-term consequences of bioenergy harvesting are unknown, particularly as Coast Range forests face novel conditions resulting from climate change. We used the LANDIS-II forest simulation model to project the impacts of climate change and management actions on above- and below-ground carbon and nitrogen dynamics in a small watershed in the northeastern Oregon Coast Range. We explored scenarios varying in future climatic conditions (including current climate and six scena...
ABSTRACT Root biomass, root production and lifespan, and root-mycorrhizal interactions govern soi... more ABSTRACT Root biomass, root production and lifespan, and root-mycorrhizal interactions govern soil carbon fluxes and resource uptake and are critical components of terrestrial models. However, limitations in data and confusions over terminology, together with a strong dependence on a small set of conceptual frameworks, have limited the exploration of root function in terrestrial models. We review the key root processes of interest to both field ecologists and modelers including root classification, production, turnover, biomass, resource uptake, and depth distribution to ask (1) what are contemporary approaches for modeling roots in terrestrial models? and (2) can these approaches be improved via recent advancements in field research methods? We isolate several emerging themes that are ready for collaboration among field scientists and modelers: (1) alternatives to size-class based root classifications based on function and the inclusion of fungal symbioses, (2) dynamic root allocation and phenology as a function of root environment, rather than leaf demand alone, (3) improved understanding of the treatment of root turnover in models, including the role of root tissue chemistry on root lifespan, (4) better estimates of root stocks across sites and species to parameterize or validate models, and (5) dynamic interplay among rooting depth, resource availability and resource uptake. Greater attention to model parameterization and structural representation of roots will lead to greater appreciation for belowground processes in terrestrial models and improve estimates of ecosystem resilience to global change drivers.
... Apatite, a ubiquitous but trace mineral in parent material, has been shown to be disproportio... more ... Apatite, a ubiquitous but trace mineral in parent material, has been shown to be disproportionately impor-tant as a source of Ca and P in young soils, because of its high weathering rate Melissa S. Lucash Dep. of Environmental Science and Management Portland State Univ. ...
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