Quantitative Models and Carbon Dynamics

Climate change has strong influences on high-latitude ecosystems. These habitats contain significant carbon stocks that may become sources for greenhouse gases to the atmosphere in a warming climate. Long-term ecosystem changes are expected with warming, changes in precipitation, and disturbances such as wildfires. We seek to understand and quantify disturbances and other changes in boreal forests by mapping differences between observed and weather-based predictions of boreal forest productivity (performance anomalies). Areas of changing ecosystems and disturbances are identified using time series maps. Histories of lake surface areas give clues to changing hydrology, connectivity to ground water, climate, water chemistry, important wildlife habitat, and sources of carbon efflux. Above-ground biomass quantification and mapping provide detailed information about carbon stocks and ecosystem productivity for biogeochemical modeling and prediction of future ecosystem responses. Below-ground soil organic layer and fall active layer depth are important ecological drivers and indicators. Below-ground remote sensing of near-surface electromagnetic resistivity gives important clues into the spatial distributions of important ecological drivers such as soil organic layers and active layers above permafrost.

Why is this research important?

Boreal forest disturbances and ecological changes give indications of stress and potential vulnerability to long-term ecosystem shifts. Post-fire vegetation recovery can be tracked to highlight significant and unexpected deviations. Models for predicting undisturbed boreal forest productivity using weather and site conditions can also provide estimates of future boreal forest response to scenarios of future climate. Observations of surface water dynamics can be combined with measurement of deeper electromagnetic resistivity to quantify ground water connectivity to lakes and to improve regional ground water modeling and projections. Mapping of exposed lake shore sediments can be used in regional estimates of carbon dioxide and methane efflux. Predictions of waterfowl habitat and water chemistry can be based on observed relationships to surface water histories. Aboveground biomass maps provide an important input for carbon flux models, vegetation models, carbon stock quantification, and ecosystem mapping. Surface electromagnetic surveys provide the ability to map soil organic and active layer thicknesses, which are very important to post-fire succession trends, vegetation changes, and hydrologic changes. This research provides fundamental information needed to understand and predict boreal forest response to climate change and disturbances such as fires and insect invasions.

Principal Investigator: Bruce Wylie, Earth Resouces Observations and Science (EROS) Center