Aquatic Plant Control Research Program. A Mathematical Model of Submersed Aquatic Plants.

Submersed auatic plants or macrophytes often contribute significantly to primary production in lakes and reservoirs. Macrtophyte growth and decomposition can influence the physical, chemical, and biological characteristics of aquatic ecosystems, including temperature and concentrations of dissolved oxygen, nitrogen, phosphorus, inorganic carbon, detritus, phytoplankton, and fish. A mathematical model of submersed aquatic macrophyte growth and decomposition was developed for use with the US Army Corps of Engineers one-dimensional reservoir water quality model, CE-QUAL-R1, which was developed under the Environmental and Water Quality Operational Studies EWQOS. The ecological processes recommended for inclusion with the macrophyte compartment include gross production, dark respiration, photorespiration, nonpredatory mortality, and grazing. The influence of these processes on other compartments in CE-QUAL-R1 is described. Select process equations have been validated using a stand-alone version of the recommended model based upon experimental results derived from the literature and other research at the US Army Engineer Waterways Experiment Station for two macrophyte species, Myriophyllum spicatum and Hydrilla verticillata. Management control strategies can be simulated for mechanical harvesting and chemical control of the plants. Keywords Aquatic ecology Aquatic plants--Mathematical models Eurasian watermillfoil and Water quality management.