Long-term Collaborative and Site-based Projects
We are involved in three long-term research projects funded by the National Science Foundation (NSF) and a fourth project that we are pursuing funding to continue:
- Luquillo NSF-LTER Project: Luquillo Experimental Forest in the El Yunque National Forest in the mountains of northeastern Puerto Rico (1985-present)
- Coweeta NSF-LTER Project: Coweeta Hydrologic Laboratory in the Nantahala National Forest in the southern Appalachian Mountains of North Carolina (1980-present)
- STREAMS NSF-LTREB Project: La Selva Biological Station in lowland Costa Rica (1986-present)
- TADS – Tropical Amphibian Declines Project: Panama (2000-present)
Both the Luquillo and Coweeta Long Term Ecological Research (LTER) Projects are part of the larger NSF-LTER network of 25 site-based projects across the US. The ecological consequences of land use change and hydroclimatic variability is a convergent theme of both projects. Our studies of stream ecosystems build on a rich history of prior LTER research, made possible by relatively continuous NSF funding over decades (i.e. extending beyond typical 3-year funding cycles) combined with support from the USDA Forest Service. This has resulted in valuable long-term data sets that better inform our research questions. Our collaborative relationship with the USDA Forest Service at both LTER sites has resulted in management applications of scientific research.
Likewise, our Costa Rica STREAMS LTREB (Long Term Research in Environmental Biology) Project, which is funded by NSF’s LTREB Program, has evolved over the decades to pursue new research directions in response to emergent patterns in long-term data: analysis of >25 year datasets on stream solute chemistry and precipitation led us to redirect our research from stream trophic dynamics and phosphorus cycling to the ecological consequences of climate-driven stream acidification.
Finally, the long-term Tropical Amphibian Declines (TADS) Project in Panama examines ecosystem-level effects of the disease-driven extinction of stream-dwelling frogs. This project builds on pre- and post-extinction datasets on stream ecosystem structure and function, providing invaluable baseline data for continued quantification of the long-term effects of an extinction event that removed an entire community assemblage of stream vertebrates.
In Situ Experimental Research in Streams
Our lab has a history of in situ experimental research in streams. We developed an experimental electric exclosure technique to isolate top-down effects of stream macroconsumers (e.g., fish, crayfish, shrimps) on ecosystem properties and processes by excluding them from foraging on the stream bottom (Figs. 1 & 2). This technique results in exclusion of macroconsumers at a local scale, and is particularly effective when combined with (or nested within) reach-scale experimental manipulations. We initially implemented this technique in our studies in Puerto Rico and Costa Rica, and it has since been used in stream studies across the world.
Environmental Outreach Activities
Environmental outreach and education have been incorporated into past and ongoing research projects. Examples range from development of posters on riverine biota and connectivity (see posters below) to the development of an outreach program (Water for Life/Agua para Vida) as part of our long-term NSF-LTREB STREAMS Project in Costa Rica.
Click on posters to enlarge