Linking Watershed-Scale Indicators of Changes in Atmospheric Deposition to Regional Response patterns

EPA Grant Number: R825762
Title: Linking Watershed-Scale Indicators of Changes in Atmospheric Deposition to Regional Response patterns
Investigators: Kahl, Jeffrey , Ballard, S. , Cosby, Bernard , Fernandez, Ivan , Ludwig, P. , Mageean, Deirdre , Norton, Sharon , Rustad, Lindsey
Institution: University of Maine , University of Virginia
Current Institution: University of Maine
EPA Project Officer: Hiscock, Michael
Project Period: September 1, 1997 through August 31, 2000 (Extended to September 30, 2001)
Project Amount: $623,395
RFA: Water and Watersheds Research (1997) RFA Text |  Recipients Lists
Research Category: Water , Water and Watersheds


This research is part of a program addressing scientific and societal needs by investigating the processes and indicators of response and recovery at the Bear Brook Watershed in Maine (BBWM). We will use the geochemical model MAGIC to predict site specific results and will then scale the results from BBWM to the regional level by re-examining the parallel spatial and temporal chemical trends in the High Elevation Lakes in Maine (HELM) and their watersheds. Concurrently, we will develop the mechanisms to present these findings in a practical format for state and federal resource managers and decision-makers, guiding them to information relevant to their goals. This latter objective is especially relevant in Maine, because of the importance of the forest products industry to the state economy.


The ecological tasks are hierarchical from site specific to regional: First, we will examine the geochemical indicators of, and model predictions for, acidification at the whole-catchment experimental site at BBWM. Because of the 7 year experimental acidification, this site is the only terrestrial ecosystem in the US where documented acidification has occurred, and where significant recovery will occur after the treatment is terminated. We will employ (MAGIC) and its sequels to predict acidification and response. This project will determine mechanisms and patterns of response in soils and stream chemistry, and in forest growth, while developing the experimentally-altered ecosystem response necessary for the evaluation of recovery. Second,, we will scale the site intensive information to a regional level using HELM watersheds. The spatial and temporal patterns for NO3 in the these lakes have not been examined since 1987 (an information need also addressed here). We will determine key soil and forest growth characteristics for these watersheds, to determine if regional soil chemical characteristics relate to nitrogen saturation and flux in the terrestrial landscape of watersheds that are already experiencing nitrate loss. Concurrently, we will focus on transferring new information about changes in water quality and forest productivity to state planners, forest products industry, and federal agencies.

Expected Results:

This information is fundamental for EPA to meet the Congressional mandate in the Clean Air Act Amendments (CAAA) to ascertain trends in ecological response, and to determine the effectiveness of the CAAA in influencing these trends. Site specific data from BBWM scaled to the regional HELM population will also provide a template for the recognition and under standing of possible N-saturation and base cation depletion that may be occurring in watersheds in the region. This information will be presented and evaluated for use in management and policy decisions by industry, and at the local, state and federal level.

Publications and Presentations:

Publications have been submitted on this project: View all 84 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 20 journal articles for this project

Supplemental Keywords:

acid deposition, sensitive populations, public policy, modeling, surveys,, RFA, Scientific Discipline, Geographic Area, Water, Ecosystem Protection/Environmental Exposure & Risk, Hydrology, Nutrients, Water & Watershed, Ecosystem/Assessment/Indicators, Ecosystem Protection, State, Ecological Effects - Environmental Exposure & Risk, Air Deposition, Ecological Risk Assessment, Ecology and Ecosystems, Watersheds, Ecological Indicators, atmospheric processes, ecosystem modeling, hydrological stability, risk assessment, acidification, geochemical modeling, atmospheric deposits, nutrient stress, aquatic ecosystems, forests, nitrate loss, regional response patterns, water quality, spatial and temporal patterns, Maine (ME), ecosystem stress, atmospheric deposition

Progress and Final Reports:

  • 1998
  • 1999 Progress Report
  • 2000 Progress Report
  • 2001
  • Final Report