MODELING THE DYNAMICS OF WETLAND MACROPHYTES - KEOLADEO NATIONAL-PARKWETLAND, INDIA

Mathematical model studies have been conducted to investigate the effe ct of excessive growth of wild grasses such as Paspalum distichum on t he growth of other macrophytes in the wetland of the Keoladeo National Park, Bharatpur, India. The model parameters are determined by the re gression analysis of the observed biomass data for the Paspalum distic hum and other aquatic macrophytes. A good agreement of numerical solut ions with the observed data shows the applicability of the model. The model results show fast growth or the Paspalum distichum to its carryi ng capacity and decay of other macrophytes to a low equilibrium densit y thus demanding proper management of the wetland. A non-linear stabil ity analysis of the control model incorporating the effort of removal of the grasses establishes the unconditional stability of the model so lutions. Applying the model to the Park's wetland, it is found that an increasing effort is required to control the wild grasses. It is also seen that an increased rate of depletion of the grasses not only redu ces their equilibrium and peak densities but also helps in restoring o ther macrophytes to the initial state. (C) 1998 Elsevier Science B.V. All rights reserved.