PROGRAM TITLE: Atmosphere/Biosphere Gas and Energy Exchange (ATBIOX) ACTIVITY STREAMS: Process/Observation, Modeling SCIENCE ELEMENT:
Biogeochemical Dynamics U.S. DEPARTMENT OF AGRICULTURE Forest ServiceDESCRIPTION: Research emphasizes the linkages and interdependency between ecosystem cycles including carbon sequestration and other means for mitigating or adapting to global change. This FSGCRP Program Element will encompass all major ecosystems and climates that contain important natural resources, such as timber, water, rangeland, wildlife, and recreational resources. ECOSYSTEMS AND SOILS--Research examines ecosystems and soils through the way in which climate and atmospheric chemistry shape and are shaped by the biological world. The research is conducted at scales from the regional to local. It focuses on (1) the carbon cycle and carbon budget with particular attention to the flux of carbon between soils, water, the atmosphere, and the biosphere; (2) greenhouse gas (CO2, CH4, N2O, H2O) exchanges with terrestrial ecosystems; (3) nutrient cycles and energy flows, and (4) regional and local climate change scenarios. A number of methodologies and modeling techniques are applied to ATBIOXÊ research. Measurements of the atmosphere adjacent to plants and communities are currently being made to determine biogenic gas fluxes- especially carbonÊdioxide and methane- and to monitor ozone and acidic deposition at manyÊlocations. Chamber experiments provide these data and UV-B radiation as well as information on increased insect stress. Soils are monitored to determineÊ trends in carbon storage and to develop an understanding of the processes that control the flux of carbon between soils, aquatic systems, the atmosphere, and the biosphere. Mechanistic models for individual species, functional groupings, and specificÊecosystems are under development to describe processes of carbon sequestration and allocation, water balance, and nutrient cycles. Biogeochemical soil models that couple climate to nutrient budgets, soil organisms, soil structure,Êfunction, and productivity are being developed. Climate change scenarios and carbon dioxide levels and distribution are applied to predict future vegetation and productivity of forests and rangelands in the U.S. Regional adaptations to global climate scenarios are provided through local and mesoscale meteorologyÊ modeling. WOOD -- Wood in use is an important adjunct to living ecosystems in mitigatingÊ the adverse impacts of global change phenomena. Sequestration of carbon inÊvirgin and recycled products is a major factor in the carbon cycle. If wood in use is maintained in service for as long as the normal growth rotation forÊ trees the sequestration of carbon per rotation is extended by a factor of 2.5.Ê Use of wood as a replacement for fossil fuel, and re-growing wood eliminatesÊ atmospheric accumulation of CO2 from fossil fuel and because of its lowÊ energy intensity, wood may be used as a material to conserve energy. RecyclingÊ wood increases carbon sequestration through extension of service life andÊ conserves the wood resource with less expenditure of energy. Ê This FSGCRP Program Element is vital to understanding and predicting theÊ structure and composition of future ecosystems. Research which quantifiesÊ carbon sequestration in biomass, organic matter, the soils of forests andÊ related ecosystems, and wood in use will be accelerated. Forests are a majorÊ repository of carbon taken from the atmosphere. Understanding the carbon cycle and its interrelationship with nutrient, water, and energy cycles is vital toÊ determining the dynamics of the global carbon budget. This program is criticalÊ to understanding and predicting CO2, CH4, and sensible and latent heatÊ fluxes in changing land use patterns. Of special interest is the role andÊ interactions of mycrorhizal fungi and other organisms in the rhizosphere withÊ host and associated environments. STAKEHOLDERS: Cooperators are DOT, EPA, DOE, NSF, NASA, U.S. Industries, Canada Department of Energy, Mines, and Resources Primary beneficiaries are consumers, industry and other researchers. SHORT-TERM POLICY PAYOFFS: Information to hold 1990 levels of carbon emissions through the year 2000.