Stand Age- and Climate Variability-effects on Ecosystem Exchange at the Wind River Experimental Forest, Washington, USA PDF Download

Author: Sonia Wharton
Publisher:
ISBN:
Category :
Languages : en
Pages : 350

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Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 57

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Book Description
This study examines how stand age affects ecosystem mass and energy exchange response to seasonal drought in three adjacent Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests. The sites include two early seral stands (ES) (0-15 years old) and an old-growth (OG) (≈ 450-500) forest in the Wind River Experiment Forest, Washington, USA. We use eddy covariance flux measurements of carbon dioxide (F{sub NEE}), latent energy ([lambda]E) and sensible heat (H) to derive evapotranspiration rate (E{sub T}), bowen ratio ([beta]), water use efficiency (WUE), canopy conductance (G{sub c}), the Priestley-Taylor coefficient ([alpha]) and a canopy decoupling factor ([Omega]). The canopy and bulk parameters are examined to see how ecophysiological responses to water stress, including changes in available soil water ([theta]{sub r}) and vapor pressure deficit ([delta]e) differ among the two forest successional-stages. Despite very different rainfall patterns in 2006 and 2007, we observed distinct successional-stage relationships between E{sub T}, [alpha], and G{sub c} to [delta]e and [theta]{sub r} during both years. The largest stand differences were (1) higher morning G{sub c} (> 10 mm s−1) at the OG forest coinciding with higher CO2 uptake (F{sub NEE} = -9 to -6 [mu]mol m−2 s−1) but a strong negative response in G{sub c} to moderate [delta]e later in the day and a subsequent reduction in E{sub T}, and (2) higher E{sub T} at the ES stands because midday canopy conductance did not decrease until very low water availability levels (

Author: Michael J. Furniss
Publisher: DIANE Publishing
ISBN: 1437939848
Category : Nature
Languages : en
Pages : 80

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This is a print on demand edition of a hard to find publication. Water from forested watersheds provides irreplaceable habitat for aquatic and riparian species and supports our homes, farms, industries, and energy production. Yet population pressures, land uses, and rapid climate change combine to seriously threaten these waters and the resilience of watersheds in most places. Forest land managers are expected to anticipate and respond to these threats and steward forested watersheds to ensure the sustained protection and provision of water and the services it provides. Contents of this report: (1) Intro.; (2) Background: Forests and Water; Climate Change: Hydrologic Responses and Ecosystem Services; (3) Moving Forward: Think; Collaborate; Act; (4) Closing; (5) Examples of Watershed Stewardship. Illus.

Author: David Greenland
Publisher:
ISBN:
Category : Bioclimatology
Languages : en
Pages : 100

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Author:
Publisher:
ISBN:
Category : Climatic changes
Languages : en
Pages : 8

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Author: James M. Vose
Publisher:
ISBN:
Category : Climatic changes
Languages : en
Pages : 265

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Book Description
This report is a scientific assessment of the current condition and likely future condition of forest resources in the United States relative to climatic variability and change. It serves as the U.S. Forest Service forest sector technical report for the National Climate Assessment and includes descriptions of key regional issues and examples of a risk-based framework for assessing climate-change effects. By the end of the 21st century, forest ecosystems in the United States will differ from those of today as a result of changing climate. Although increases in temperature, changes in precipitation, higher atmospheric concentrations of carbon dioxide (CO2), and higher nitrogen (N) deposition may change ecosystem structure and function, the most rapidly visible and most significant short-term effects on forest ecosystems will be caused by altered disturbance regimes. For example, wildfires, insect infestations, pulses of erosion and flooding, and drought-induced tree mortality are all expected to increase during the 21st century. These direct and indirect climate-change effects are likely to cause losses of ecosystem services in some areas, but may also improve and expand ecosystem services in others. Some areas may be particularly vulnerable because current infrastructure and resource production are based on past climate and steady-state conditions. The ability of communities with resource-based economies to adapt to climate change is linked to their direct exposure to these changes, as well as to the social and institutional structures present in each environment. Human communities that have diverse economies and are resilient to change today will also be prepared for future climatic stresses. Significant progress has been made in developing scientific principles and tools for adapting to climate change through science-management partnerships focused on education, assessment of vulnerability of natural resources, and development of adaptation strategies and tactics. In addition, climate change has motivated increased use of bioenergy and carbon (C) sequestration policy options as mitigation strategies, emphasizing the effects of climate change-human interactions on forests, as well as the role of forests in mitigating climate change. Forest growth and afforestation in the United States currently account for a net gain in C storage and offset approximately 13 percent of the Nation's fossil fuel CO2 production. Climate change mitigation through forest C management focuses on (1) land use change to increase forest area (afforestation) and avoid deforestation, (2) C management in existing forests, and (3) use of wood as biomass energy, in place of fossil fuel or in wood products for C storage and in place of other building materials. Although climate change is an important issue for management and policy, the interaction of changes in biophysical environments (e.g., climate, disturbance, and invasive species) and human responses to those changes (management and policy) will ultimately determine outcomes for ecosystem services and people. Although uncertainty exists about the magnitude and timing of climate-change effects on forest ecosystems, sufficient scientific information is available to begin taking action now. Building on practices compatible with adapting to climate change provides a good starting point for land managers who may want to begin the adaptation process. Establishing a foundation for managing forest ecosystems in the context of climate change as soon as possible will ensure that a broad range of options will be available for managing forest resources sustainably.

Author: Peterson David L.
Publisher: Springer
ISBN: 9789402402728
Category : Science
Languages : en
Pages : 0

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This volume offers a scientific assessment of the effects of climatic variability and change on forest resources in the United States. Derived from a report that provides technical input to the 2013 U.S. Global Change Research Program National Climate Assessment, the book serves as a framework for managing U.S. forest resources in the context of climate change. The authors focus on topics having the greatest potential to alter the structure and function of forest ecosystems, and therefore ecosystem services, by the end of the 21st century. Part I provides an environmental context for assessing the effects of climate change on forest resources, summarizing changes in environmental stressors, followed by state-of-science projections for future climatic conditions relevant to forest ecosystems. Part II offers a wide-ranging assessment of vulnerability of forest ecosystems and ecosystem services to climate change. The authors anticipate that altered disturbance regimes and stressors will have the biggest effects on forest ecosystems, causing long-term changes in forest conditions. Part III outlines responses to climate change, summarizing current status and trends in forest carbon, effects of carbon management, and carbon mitigation strategies. Adaptation strategies and a proposed framework for risk assessment, including case studies, provide a structured approach for projecting and responding to future changes in resource conditions and ecosystem services. Part IV describes how sustainable forest management, which guides activities on most public and private lands in the United States, can provide an overarching structure for mitigating and adapting to climate change.

Author: Paul Hanson
Publisher: Springer Science & Business Media
ISBN: 1461300215
Category : Science
Languages : en
Pages : 487

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Large-scale experimentation allows scientists to test the specific responses of ecosystems to changing environmental conditions. Researchers at Oak Ridge National Laboratory together with other Federal and University scientists conducted a large-scale climatic change experiment at the Walker Branch Watershed in Tennessee, a model upland hardwood forest in North America. This volume synthesizes mechanisms of forest ecosystem response to changing hydrologic budgets associated with climatic change drivers. The authors explain the implications of changes at both the plant and stand levels, and they extrapolate the data to ecosystem-level responses, such as changes in nutrient cycling, biodiversity and carbon sequestration. In analyzing data, they also discuss similarities and differences with other temperate deciduous forests. Source data for the experiment has been archived by the authors in the U.S. Department of Energy's Carbon Dioxide Information and Analysis Center (CDIAC) for future analysis and modeling by independent investigators.

Author: Martin Beniston
Publisher: Springer
ISBN: 3540691073
Category : Science
Languages : en
Pages : 471

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This volume contains a selection of scientific papers which were presented at an international workshop on the impacts of climatic variability held in Wengen, Switzerland, September 1997. For the first time, an assessment is made of the interactions between physical and biological elements of the Earth System on the basis of shifts in extreme climatic conditions, rather than simply changes in mean atmospheric conditions which research has tended to focus on until recently. Natural ecosystems and forests are typical examples of systems which, while constrained within certain ranges of mean climate, can undergo rapid and often irreversible damage in the face of short-lived but intense extreme events.

Author: Paul Hanson
Publisher: Springer
ISBN: 9780387003092
Category : Science
Languages : en
Pages : 472

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Book Description
Large-scale experimentation allows scientists to test the specific responses of ecosystems to changing environmental conditions. Researchers at Oak Ridge National Laboratory together with other Federal and University scientists conducted a large-scale climatic change experiment at the Walker Branch Watershed in Tennessee, a model upland hardwood forest in North America. This volume synthesizes mechanisms of forest ecosystem response to changing hydrologic budgets associated with climatic change drivers. The authors explain the implications of changes at both the plant and stand levels, and they extrapolate the data to ecosystem-level responses, such as changes in nutrient cycling, biodiversity and carbon sequestration. In analyzing data, they also discuss similarities and differences with other temperate deciduous forests. Source data for the experiment has been archived by the authors in the U.S. Department of Energy's Carbon Dioxide Information and Analysis Center (CDIAC) for future analysis and modeling by independent investigators.