Formulating and Solving Nonlinear Integrated Ecological-Economic Models Using GAMS

In order to analyze, understand and prescribe natural resourcemanagement strategies, the decision making framework should ideallycapture the dynamics of inter-dependency between the economic andecological systems in an integrated manner. However, by including twocomplex systems within a single integrated framework makes many of thepresent analytical tools redundant. Computational models on the otherhand are ideally suited to meet this challenge. The size and complexityof models solved through numerical techniques have increasedexponentially over the last decade. This is especially true fornon-linear optimization models. However, although the science of solvingnon-linear models has improved significantly, the solving of thesemodels is still an art. In this paper, we look at the criticalparameters that a modeler needs to be aware of when developingintegrated economic-ecology models and some `tricks' to solve them withthe minimum of effort through the use of the optimization software GAMS(General Algebraic Modeling System).