The Arctic LTER Project: Regional Variation in Ecosystem Processes and Landscape Linkages

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This is the fourth stage of the Arctic LTER (ARC) located at the Toolik Lake Field Station, Alaska, where the ecology of tundra, streams, and lakes is studied to understand controls on ecosystem structure and function within the long-term goal of predicting the effects of environmental change. Research has been ongoing at the station since the 1970s, with the LTER project focusing on the biogeochemical components of a series of connected streams and lakes that collectively flow into and affect Toolik Lake, as well as the adjacent headwaters region of the Kuparuk River. Extensive variability exists among the various terrestrial and aquatic ecosystems in the study area, but all are linked via water and materials transport. The goal for this next phase of ARC is to understand changes in the Arctic system at catchment and landscape scales through enhanced knowledge of these linkages and interactions. Research will identify and quantify intra- and inter-system linkages, determine controls of the linkages and how they will be affected by a changing environment, and predict how the entire landscape will respond to environmental change. A suite of biogeochemical studies will target the interactions among the component terrestrial, stream, lake ecosystems within this landscape. Short-term studies will focus on specific materials to better understand inputs, climate drivers and transformations of materials. Long-term studies will investigate effects of changes in species composition, temperature, light and nutrients on four types of tundra and the effects of nutrient loading and climate variability. Lake studies will focus on landscape-to-lake linkages to understand controls of terrestrial patchiness on productivity patterns in lakes. Researchers will also examine in-lake processes and their relations to watershed inputs of nutrients and dissolved organic matter. Objectives are to measure pelagic and benthic production and coupling, illucidate food web structures, and determine how watershed-stream-lake linkages regulate transformations in water chemistry and patterns of productivity. Broader Impacts center around the use of ARC research results to address the important societal goal of predicting responses of Arctic ecosystems to environmental change. Data and insights will be provided to Federal and State officials regulating the development of oil and gas on the Alaskan North Slope. A collaborative undergraduate/graduate course will be held for two weeks in the summers, with undergraduate students trained in the field along with graduate students from ten universities. The MBL's Science Journalism Course facilitates journalist visits to Toolik Lake. The ARC LTER Schoolyard project involves a majority of Native Alaskan students. K-12 students conduct and observe local field experiments similar to those at Toolik Lake. Finally, participating ARC scientists actively engage students, residents and local community officials in the region by presenting volunteer lectures on science topics.