A dynamic programming approach to optimal grazing strategies using a succession model for a tropical grassland

Abstract

This paper shows an application of operations research techniques for promotion of decision making in grazing management. The research described here simulated grass-land succession on an Indian grassland on the basis of plant cover data collected for two successive years in pastures having different intensities of grazing. The succession simulation was developed using a transfer matrix for yearly change of plant cover between species. Transfer functions were then developed for each of four intensities of grazing from ungrazed to heavily grazed. These were used in developing a long-term optimal grazing pattern using dynamic programming. The objective function was not simply to optimize utilization, but was to achieve a combined objective involving diversity, leguminous plants, bare space, and the density of the dominant forage plant Dichanthium annulatum as well as utilization. Results from the optimization show a combination of moderate grazing with an occasional light grazing year as the best grazing strategy for our objectives over a 12-year grazing horizon.