The proposed project represents a synthesis of classical ecological stream research and the use of new applications of remote sensing to detect an important ecological response variable, attached algae. A series of laboratory experiments will be conducted where artificial stream pools with natural bottom substrates will be manipulated to determine the effects of water depth, surface reflectance, turbidity, and phytoplankton density on attached algal spectral reflectance. Also, an in situ stream experiment will be conducted to determine the effects of benthic complexity and nutrient availability on the cascading trophic patterns, which controlled benthic algal biomass in the laboratory experiments. Spectral reflectance from all experiments will be measured using a narrow-band spectroradiometer and ground-truth samples will be taken for periphyton chlorophyll content and pertinent water quality variables. Two similar in situ stream experiments conducted by other researchers in different geographic locations will be sampled in the same way. In collaboration with remote sensing experts from the University of Kansas, University of Nebraska, and Creighton University (NB), spectral reflectance data from this project will be used to develop and refine a spectral reflectance model for periphyton in streams.
