英文摘要: | Stream and rivers are being assaulted by myriad environmental stresses, including elevated nutrient inputs, species extinctions and invasions, and loss of biodiversity. In the contiguous US, nitrogen inputs have tripled relative to levels during pre-European settlement, primarily due to synthetic fertilizer production, atmospheric deposition from the combustion of fossil fuels, and through agricultural practices. Consequently, many streams have dramatically higher nutrient concentrations than they did historically, which can lead to algal blooms, fish die-offs, and increased export of nutrients to marine ecosystems. Streams can be important for regulating nutrient exports from continents to oceans, but the functioning is, in part, mediated by biodiversity, and rates of species losses in streams are among the highest on the planet. Therefore, understanding interactions among changing nutrient inputs, and declining biodiversity are major and immediate challenges for conservation and management of freshwater ecosystems. The number of available datasets on stream nutrient concentrations, stream flow, and biodiversity has increased rapidly, but many have yet to be evaluated for temporal or spatial trends, analyzed with state of the art statistical and modeling techniques, or compared across regions. Further, many large datasets are coming online in the near future, and stream ecologists need to develop strategies to best utilize this emerging information. The goal of the Stream Resiliency Research Coordination Network is to link stream ecologists with hydrologists, statisticians, modelers, and resource managers to develop a synthetic understanding of how streams and river ecosystems will respond to chronic nutrient inputs and changing species diversity. The network will meet through a series of workshops and webinars to develop new approaches to analyzing existing and forthcoming stream nutrient and organism datasets, and conduct state of the knowledge syntheses. An initial one-day planning workshop associated with the 2014 Joint Aquatic Sciences meeting will be hosted to engage the research community. Following the planning meeting, four three-day workshops will be held addressing topics focused on understanding long-term change in stream ecosystems, how ecosystem processes vary across river networks from small headwater streams to larger rivers, and the interactions among organisms in the context of changing climate, altered land-use, and loss of biodiversity. Each workshop will include one day focused on training in data analysis and modeling approaches not typically used by stream ecologists, and two days focused on data analyses and synthesis. In the last year of funding, a workshop will be hosted at the annual meeting of the Society for Freshwater Science to report back to the scientific community the activities of the network, and host a series of presentations about the state of knowledge.
Key functions of the network include enabling interactions among researchers and managers, and providing opportunities for young scientists to collaborate with established scientists. The network will focus on developing novel conceptual frameworks and new analytical approaches to facilitate the synthesis of a wealth of existing datasets, as well as to provide the foundations for interpreting and guiding new research projects and sampling, and training opportunities for the next generation of scientists in the methods needed to deal with long-term datasets spanning large spatial scales. Each workshop will include training of a targeted statistical or modeling approach, provide educational opportunity for both graduate students and established researchers, and produce tangible applied products for natural resource managers and policy makers. In addition, an online graduate level seminar will be hosted focusing on stream functioning in a changing environment, providing an opportunity for students across the globe to learn about the activities and findings from the network. |