research project details
Project Title: Hydrologic Forecasting for Characterization of Non-linear Response
of Freshwater Wetlands to Climatic and Land Use Change in the Susquehanna River Basin
Investigator(s): Denice
Wardrop, Rob
Brooks, Kevin
Dressler, Chris
Duffy, William
Easterling, Ray
Najjar, Rich
Ready, and Jim Shortle
Sponsor: National
Science Foundation
Objective: To characterize nonlinear responses to global climate change in linked aquatic and terrestrial ecosystems through
- Selection of a linked terrestrial-aquatic ecosystem that provides critical ecosystem services and ecological functions,
- Characterization of various global change scenarios, incorporating both climate and land cover, and a method of assessing their effect on the identified ecosystem through the primary forcing factor of hydrology (both alone and in conjunction with other human-associated stressors),
- Identification of potential nonlinear ecological responses (sensu Scheffer et al., 2002) in the selected ecosystem as a result of these changes, and
- Estimation of the resultant change in ecosystem services on a watershed and Basin-wide scale in the Susquehanna River Basin.
Approach: Our general approach to investigating the response of freshwater wetlands to climatic and land use change is based on tools and products of four previous EPA-STAR grants, and involves the following series of activities:
- Develop scenarios of climate and land cover change, operating on a scale of decades, relevant to the Susquehanna River Basin (SRB).
- Using these scenarios, in conjunction with a coupled surface-ground water model, develop a number of predictive hydrologic scenarios for a collection of 11-digit HUC watersheds representing a range of human-associated land uses in the SRB.
- Characterize the relationships between hydrologic and landcover parameters and ecosystem characteristics and services in wetlands of various types in the SRB, focusing on those with preliminary evidence of non-linearity and/or thresholds.
- Utilize the predicted hydrologic scenarios to forecast changes in ecosystem services across the entire Susquehanna River Basin, clearly identifying where and when non-linearities and/or thresholds in response occur, utilizing a series of unique statistical tools to develop a probability surface.
Expected Results: We will develop a unique analytical method for prediction of climate and land cover change impacts, incorporating the forecasting of hydrologic conditions, which can be used to identify thresholds and non-linearities in the functional performance of freshwater wetlands. Any set of hydrologic/land cover change conditions can then be placed upon the probability surface, allowing the statistical model to be used in a predictive fashion. The method could be applied to a wide variety of aquatic ecosystems for which state changes occur over either a spatial and temporal extent, or both.