Development of a Spatial Decision Support System (SDSS) for Grape Cultivation by Using a Geographical Information System (GIS): Çatak (Turkey) Example

This study aims to develop a spatial decision support system (SDSS) by evaluating climate, soil, and topography factors together with the help of a Geographical Information System (GIS) and by using this modelled SDSS to determine the potentially suitable areas where grape varieties with different ripening levels within the study area (Çatak, Turkey) can be grown. The study was carried out in the Çatak district, located in the south of Lake Van, between 4080000 and 4240000 north latitudes and 300000 and 370000 east longitudes (UTM WGS84) in eastern Turkey in 2021–2022. In the study, some important individual factors for vine growing such as the effect of heat summation (EHS), number of frost-free days, minimum winter temperature, aspect, slope, soil depth, and land use capability were evaluated using the GIS and weighted notation ratio result method, and based on this, a suitability analysis was carried out. It was determined that the distributions of the study area for first, second, and third suitability levels, respectively, were 0.72–26.05–52.50% for the earliest variety, 4.58–33.84–48.28% for the early variety, 1.15–22.56–58.47% for the mid-early varieties, 3.95–20.52–49.07% for the mid-season varieties, and 1.18–13.20–44.61% for the late variety. It was seen that the variables and the modelling used were effective in determining suitable areas for grape cultivation.