Integration of atmospheric deposition and water quality monitoring in the El Yunque National Forest, Puerto Rico

Anita K. Rose1, Richard Pouyat2, Linda Geiser3, David Levinson4, Chelcy Miniat5, Bret A. Anderson6, Helen M. Amos7 and Denice Shaw8

Excess levels of nutrients (nitrogen and phosphorus) in surface water are associated with increased biological stress and decreased biological diversity. There is a significant need to enhance connections between atmospheric deposition monitoring and surface water quality monitoring to better understand linkages between air quality and the health of aquatic ecosystems. The limited integrated air/water monitoring we currently have is almost exclusively concentrated in temperate latitudes. El Yunque National Forest, Puerto Rico offers a unique opportunity to investigate air/water linkages because (1) watershed N/P loads are dominated by atmospheric inputs, (2) it already has an NADP super site, and (3) it is a tropical rainforest that experiences frequent, intense convective storms that are major source of lightning NOx. As part of WADeIn (Water Quality & Atmospheric Deposition Integration) -- an interagency collaboration improving the coordination and integration of atmospheric deposition and surface water quality monitoring to fill critical knowledge gaps about the sources, transport, and impacts of N and P -- the USDA Forest Service is proposing to install real-time water quality sensors for nutrients in the El Yunque National Forest. The goal is to integrate the resulting data with those from the NADP super site that currently exists in the National Forest. This pilot study will demonstrate the usefulness of the selected water sensors for quantification of nutrients in stream and provide quantitative information about how closely coupled stream nutrient exports are to atmospheric inputs. The window of opportunity for the El Yunque pilot is very timely and will be able to leverage a number of other pilots launching on similar timelines by other agencies and organizations. Additional benefits of the El Yunque pilot include: outreach to the local community through the El Yunque National Forest visitor center; test usefulness of sensors to be deployed as part of the recently established Watershed Condition Framework; foster collaborations between the Forest Service’s National Forest System and Research and Development branches, EPA, NOAA, and USGS. Results from this pilot study will provide an opportunity to further explore integrated air/water quality monitoring, as well as provide a much needed investigation into the status of watershed/water quality in the El Yunque National Forest.


1USDA Forest Service,
2USDA Forest Service,
3USDA Forest Service,
4USDA Forest Service,
5USDA Forest Service,
6USDA Forest Service,