Why sample streams?  Streams serve as integrators of the landscape and by measuring various constituents within the water we are able to assess watershedfunctions (e.g. nutrient availability).  In addition, sampling streams provides us information about the stream ecosystem and how it functions (e.g. dissolved organic material quality and quantity and planktonic community composition).

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By monitoring the biogeochemistry of the streams draining the 3 catchments we are able to assess how variations in erosional regime translate to stream nutrient and carbon dynamics. Characterization of dissolved organic matter (DOM) is a focus of a number of researchers.  DOM is of interest because it is exuded by vegetation and in turn influences weathering rates (See Weathering Section), feeds and is transformed by soil microbial communities (See Microbe Section) and is eventually leached to streams. 

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Concomitant measurements of nitrogen constituents and processes within the streams will be linked back to the quality and quantity of available organic matter.  By combining this information with microbial community characterizations (Microbe Section) process based models examining the interactions between microbes, nutrient fluxes, and vegetation can be built for both terrestrial and stream environments.

 

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These models will inform us about the availability of stream phosphorus and nitrogen which potentially influences the presence of an invasive diatom, Didymosphenia geminata (World of Didymo). While not toxic to humans, the spread of didymo disrupts stream habitats, affecting macroinvertebrate and fish communities.