Applications of modeling to vegetation management

A review of modeling applied to vegetation management shows that these models range in resolution from simple yield equations to complex representations of processes affecting growth and competition for light, water, and nutrients. The latter models inform scientists and managers about mechanisms involved, while the former are more likely to be applied by managers to estimate effects of competition. Six generic model forms were identified. Models may be further categorized by whether they focus on weed population dynamics or on processes directly affecting growth of crop plants. There is scope for these aspects of vegetation modeling to be combined. Extremely complex models are scientifically satisfying as repositories of knowledge, but they tend to be excessively parametarized and recursive. Models with many parameters are difficult to fit to specific situations because they are ambiguous; the same overall estimates of growth can be achieved in a variety of ways. In addition, their recursive nature leads...