Algae and Aquatic Macrophytes

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Algae and Aquatic Macrophytes below Glen Canyon Dam Primary production from algae represents the base of food webs in many rivers, and dissolved oxygen is a by-product of primary production. By developing detailed dissolved oxygen budgets for a river reach, which account for rates of air-water gas exchange, it is possible to estimate rates of primary production for entire reaches of river. GCMRCs Sediment Transport Group is continuously measuring dissolved oxygen concentration at 5 locations downstream of Glen Canyon Dam. In collaboration with Robert Hall and Robert Payne, the Aquatic Ecology Group is developing models for continuously estimating rates of primary production of the Colorado River in Glen, Marble, and Grand Canyon. [1]

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Updates Chara Cladophora

Links and Information Aquatic Foodbase GCMRC Aquatic Food Base Lab Measuring Primary Production in the Lees Ferry Reach Papers and Presentations 2012 Hall et al. 2012. Air-water oxygen exchange in a large whitewater river. Limnology and Oceanography: Fluids and Environments 2: 1-11. 1991 Algal and Invertebrate Biota in the Colorado River: Comparison of Pre- and Post-Dam Conditions 1988 The utilization of Cladophora glomerata and epiphytic diatoms as a food resource by rainbow trout in the Colorado River below Glen Canyon Dam, Arizona 1981 A survey of the aquatic flora and fauna of the Grand Canyon Other Stuff Cladophora is a structural host for Gammarus and chironomids below Glen Canyon Dam (Shannon et al., 1994; Stevens et al., 1997), and diatom epiphytes on the alga provide a food resource for these invertebrates (Blinn et al., 1992; Stevens et al., 1997). [2]