PS 47-135
Decomposition in aquatic and terrestrial invaded systems: A collaboration among ecologists at primarily undergraduate institutions

Wednesday, August 7, 2013
Exhibit Hall B, Minneapolis Convention Center
Tracy B. Gartner, Environmental Science and Biology, Carthage College, WI
Carolyn L. Thomas, Ferrum College

Through the Ecological Research as Education (EREN) Network, researchers from Primarily Undergraduate Institutions (PUIs) have been developing collaborative research projects to  maximize student engagement in science while generating data to address regional to continental questions. Participants in one of the EREN pilot research projects, the Decomposition in Aquatic and Terrestrial Invaded Systems (DATIS), are using a common, web-accessible litterbag protocol to collect decomposition data for invasive and native species. Leaf decomposition in aquatic and terrestrial ecosystems is a critical ecosystem level process and many invasive species have been documented to significantly alter nutrient dynamics within the areas they invade. Furthermore, while there are many experiments that have examined decomposition in aquatic or terrestrial systems, methods tend to vary between these two types of ecosystems and there have been few attempts to link these interacting environments. Our objectives for this study are to (1) develop and test integrative protocols for aquatic and terrestrial decomposition that can be conducted at PUIs, (2) evaluate previous studies suggesting decomposition rates of invasive species are faster than the decomposition rates of native species across a wide range of environments and (3) identify the threshold of invasive abundance necessary to affect decomposition rates.


Though results are preliminary and are expected to vary among sites, invasive litter did decay faster than its native pairing when it was decaying in an aquatic environment in Minnesota, with 60.3 ± 31.3% mass loss in invasive buckthorn (Rhamnus cathartica) compared to 2.5 ± 2.7% mass loss from native black cherry (Prunus serotina), and 39.16 ± 14.2% mass loss in a 50:50 mixture of the two species. Other sites should soon be reporting their first datasets for comparison. Thirty-one faculty participants at 27 different institutions have been active in this first year of the project. Throughout the project, most faculty have tried to integrate this project into their laboratory curriculum, and one emerging challenge has been finding pedagogically useful classroom time to dedicate to the iterative nature of the project after the content and skills have initially been explored. We have found that combining types of experiences across courses (e.g. field experience from one traditional class partnering with an independent researcher) has been effective in addressing these concerns. Ultimately, EREN facilitates collaboration among faculty and the students at PUIs and is an essential tool for researchers and educators at these institutions.