| Summary: | The Arctic appears to be affected by climate change more so than any other region on Earth. Some of the most significant climate change impacts reported for the Arctic are associated with dramatic shifts in the hydrologic regime of terrestrial ecosystems. Understanding the hydrologic processes that are associated with different components of arctic terrestrial ecosystems is important because water in the form of snow or rain influences a range of properties and processes such as land-atmosphere energy and trace gas fluxes, nutrient cycling, ecosystem dynamics, biodiversity, periglacial processes and surface albedo. Furthermore, plants, animals, and native people of the Arctic depend on these ecosystems and a substantial hydrologic shift could significantly impact provision of ecosystem goods and services and, therefore, natural system and human well being. A climatic warming and drying trend has been observed in Northern Alaska, near the Iñupiat Village of Barrow as well as elsewhere in the Arctic. Importantly, there remains a great deal of uncertainty as to how coastal tundra ecosystems will respond to such a trend. To assist in addressing this uncertainty, a large-scale, multi-investigator flooding and draining experiment was initiated in summer 2005, and plot to landscape responses of multiple parameters (i.e. soil moisture, plant phenology, and trace gas flux) were measured. The experimental area was situated on the Barrow Environmental Observatory in a vegetated drained thaw-lake basin (DTLB) that was divided into three treatment areas: an experimentally flooded section, an experimentally drained section, and a control section that was not flooded or drained. For this thesis, baseline hydrology data were gathered between 2005 and 2007, prior to the initiation of the flooding and draining experiment. Measurements were continued in 2008 but under experimental conditions (+/- 10 cm flooding/draining respectively). The overarching goal of this thesis is to characterize baseline hydrologic conditions in the ...
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