A GIS-BASED DYNAMIC LAND USE MODEL FOR BARTIN-ULUPINAR WATERSHED MANAGEMENT Melih ÖZTÜRK Boğaziçi University, Institute of Environmental Sciences, 34342, Bebek-stanbul. melih.ozturk@boun.edu.tr Ali Kerem SAYSEL Nadim COPTY Abdurrahim AYDIN stanbul University, Forestry Faculty, Bahçeköy-stanbul ABSTRACT A dynamic land use model is being developed for Bartın-Ulupınar watershed management. The watershed covers 375 km 2 , ultimately draining to a reservoir that supplies water to Bartın, Amasra and İnkumu city centers. Land use types repre- sented in the model structure are based on two digitized maps for years 1986 and 2006. The model structure consists of state variables representing land use types within the watershed such as forest, agriculture, settlement, forest open space, pas- ture and sand dune. Forest lands are further categorized according to their stand type as coniferous, deciduous or mixed, and according to their stand age (DBH- Diameter at the Breast Height) and stand crown closure that characterize their major hydrological parameters: the leaf area index (LAI) and the root distribution function (RDF). The model simulates the regeneration, intensification, maturation, purifica- tion and degradation processes of the different forest categories, various plantation activities of forestry authorities and land transformation in between agricultural, settled and forested lands. For initializing the model, the 1986 land use map is digi- tized using Geographical Information Systems (GIS). According to the initial simula- tion results, the change in land use categories does almost correlate the change in 1986-2006 maps. However, yet, further information is required to enrich and test the current model hypotheses on land transformation. In future work, the dynamic land