Soil Erosion Models and Implications for Conservation of Sloping Tropical Lands

*C.W. Rose, Faculty of Environmental Sciences, Griffith University, Queensland 4111, Australia. *Corresponding author: [email protected] ABSTRACT A catena of modeling approaches are briefly reviewed including dynamic stochastic and deterministic approaches. It is shown that a dynamic stochastic description of soil erosion, with appropriate parameter identification, can be identified with a deterministic description of processes, but these descriptions are mutually helpful. The role of such dynamic process models is reviewed, but more attention is given to simpler limited-parameter models and their use in extensive multi-country field studies in Southeast Asia and Australia. Extensive hydrologic data collected on runoff could be adequately interpreted using a single-parameter model of infiltration reflecting the dominant dependence of infiltration rate on rainfall rate. Data on soil and water loss from bare-plot treatments were interpreted to yield a single soil erodibility parameter at each site. The effectiveness of a variety of soil conservation options appropriate to the humid tropics was evaluated, and process studies drawn upon to seek generalization of this evaluation. The issues of model prediction of soil and water loss are also briefly considered.