PROGRAM TITLE:  	Ecological System Dynamics (ECODYN)
ACTIVITY STREAMS:  	Process/Observations, Modeling, Assessment
SCIENCE ELEMENT:  	Ecological Systems and Dynamics
Forest Service
DESCRIPTION:  The Ecosystem Dynamics research component of our 
mission focuses on the response of terrestrial and aquatic ecosystems--forest, 
range, and  wildland; wetlands, lakes, and rivers--to global change.  Research 
is conducted  at the local and regional levels.  It is directed at (1) 
understanding basic ecosystem processes, such as elemental cycling and 
responses to a changing physical and chemical environment; (2) 
determination of plant and animal species composition and the critical 
characteristics that ensure viable  functioning of each component of the 
whole ecosystem; (3) evaluation of water quality and quantity and the impact 
of changes in these characteristics on biological diversity as well as the role of 
forests and rangeland in protecting  water quality and quantity; and, (4) 
assessment of environmental impacts on vegetation and soil and the 
resulting effects on ecosystem dynamics.
 The objective of this research is to understand and anticipate the 
ecosystem changes that will result from altered environmental conditions 
and to understand the sensitivity of key ecosystem processes and components 
to different levels of stress.  Species migration and ecosystems composition  
changes will be predicted based on climate, weather, and air 
pollution scenarios derived from general circulation models and other 
sources.  Threshold limits of ecosystem stability and diversity will be 
determined.  Life  histories, population dynamics, competitive interactions, 
and community dynamics of plants and animals under altered environments 
are being studied.  Threatened, endangered, and sensitive species are also 
being studied.
 Accomplishments to date include an extensive information base on current 
forest and rangeland health, experimental results defining health and 
function of forest tree species and ecosystem process under current and 
estimated future  climate and pollution.  Numerous modeling research 
projects have provided distribution and productivity for major vegetation 
types.  Modeling projects  have also identified how individual plant and 
communities are impacted by pollution and climate.  Ecosystem and biome-
level projection of soil-water balance and streamflow have also been 
completed.  A number of projects have analyzed the role of forests (both 
vegetation and forest soils) as sinks and sources of greenhouse gases.  
Management and adaptation strategies are being investigated.  Scientists in 
the program are active participants in the Intergovernmental Panel for 
Climate Change assessments and USDA Forest Service global change 
summaries for the Resource, Planning, and Assessment five-year reports to 
 The products and performance measures are peer reviewed publications 
from this effort numerous peer reviewed publications have been completed 
and many more are being compiled or are planned.
STAKEHOLDERS:  Forest land managers, policy makers, producers and 
consumers of forest products (both market and non-market), and federal 
SHORT-TERM POLICY PAYOFFS:  Input to President's greenhouse gas 
emission policy, sound management of this critical sector of the economy.