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Ecosystem Dynamics Research
The Ecosystem Dynamics research component focuses on the response
of terrestrial and aquatic ecosystems (forest, range, and wildland;
wetlands, lakes, and rivers) to global change. 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. Ecosystems Dynamics research employs a variety
of techniques and methodologies that are dependent on the scale
of inquiry. So, it has been divided into three sub-elements according
to scale:
Basic Plant Processes -- To understand basic plant processes, chamber
experiments are conducted to determine plant responses to altered
physical environments -- enhanced CO2, O3, and acidic deposition;
changes in temperature and moisture availability; and increased
insect stress. Controlled experiments provide data on genetic resilience
to stress and adaptability of individual plants to changing environments.
Ecosystem Processes -- To understand ecosystem processes, long-term
investigations of hydrology, soils, and forest communities are conducted
in experimental forests and watersheds maintained by the Forest
Service and cooperators. Additional extensive observations are made
along environmental gradients and across ecotones. Paleoecology
is used as an historical base for forest health and productivity.
Sensitivity of the mechanisms of nutrient cycling by microbes and
small soil animals to global change is also studied.
Regional Impacts -- At the regional scale, ecosystem models and
resource production models are used to synthesize and extrapolate
the results of experimental and observational research. Such models
help us understand and predict how ecosystem productivity and vegetation
distribution may respond to global change.
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