Multi-purpose land monitoring using the Collect Earth: A case study of the Upper Sakarya basin, Turkey

Upper Sakarya Basin in Turkey, which has Cropland, Forestland, Grassland, forest, pastureland and settlements characteristics, is an effective part of the ecosystem including industry, agriculture and culture landscape. In addition, it is the main basin that needs to be monitored and evaluated for land cover and land use in terms of the sustainability of ecosystem services due to its population and current landscape. Therefore, some studies have been conducted within the scope of the Upper Sakarya Basin Global Environment Facility (GEF) project. The goal of this study is to collect tangible data for the determination of land use/cover change, land productivity, loss / gain areas within the scope of Land Degradation Neutrality (LDN), and to contribute to the existing project results by providing data to the studies within the scope of the GEF project. As a relevant methodology, the Collect Earth (CE) method was used by Food and Agriculture Organization (FAO) was employed. The findings showed that between 2000 and 2020, land use/cover classes change was in favor of forest areas, while loss areas were in favor of residential areas. According to the plant index data, the gain areas covering the improvement/greening areas were determined to be about 5 times the size of the lost areas covering the degradation/desertification areas. The same proportion was reflected in the Net Primary Productivity (NPP) increases. In this study, the first two of the change parameters in an area within the scope of LDN, land cover and use, and NPP data were collected. The other criterion, Soil Organic Carbon (SOC) data are missing in this study. As a result of this study, two main criteria were determined among the UNCCD's progress reporting indicators for LDN and proved the effectiveness of the relevant methodology in land monitoring and evaluation studies by using the Collect Earth method.