Management strategies for tropical rain forests: Results of ecological models and requirements for ecological-economic modelling

In this study, we use two ecological forest models, namely FORMIX3 and FORREG, to analyse the impact of logging on tropical rain forests and to discuss needs for and problems of an economic extension of these models. The FORMIX3 model simulates spatial-temporal dynamics of tropical forests using an individual and process based approach. The main processes included are growth, mortality, competition, and regeneration of trees. The FORREG model simulates wood growth of tropical forests at landscape scale based on differential equations. Regeneration capabilities of logged forests are analysed and compared for different logging strategies. While conventional management strategies with a short logging cycle (here 20 years) produce low yeilds and cause severe changes in tree species composition, a reduced impact logging strategy with a longer cycle (here 60 years) leads to relatively high yields and causes moderate changes in species composition. Thus, longer logging cycles are preferable from an ecological point of view. However, also economic aspects influence logging decisions, thus a closer analysis of additional economic aspects of forest management is inevitable. We discuss which economic:shortcomings of present rain forest models should be dealt with in the future and which additional data is needed as a consequence. (c) 2006 Elsevier B.V. All rights reserved.