Assessment of long-term land use and land cover change effects on soil erosion and soil organic carbon stock in humid ecosystem condition

Abstract

This study examined the consequences of land use and cover (LULC) changes on soil erosion and soil organic carbon in the Ünye district of Ordu province in the Central Black Sea Region where humid conditions prevailed in 1999, 2009, and 2019. GIS-based Revised Universal Soil Loss Equation (RUSLE) modeling approach, geostatistics and remote sensing techniques were employed in the study. According to the results considering the long years in the study area, the most relative change among LULC species was hazelnut fields with an increase of 167%. In this process, it has been determined that there are few spatial changes that occurred in artificial areas and pasture lands. In addition, in the classes of soil erosion rates defined by RUSLE, the areas classified as Very Low–Low (< 5 tons ha−1 year−1) for many years inhabit the largest area in the study area. The loss in the amount of soil organic carbon (SOC) is determined to have occurred mostly in areas with Very Low and Low erosion rates. However, it has been determined that SOC loss ensues in areas with Very High (> 20 tons ha−1 year−1) erosion rates, albeit slightly. Therefore, even in the areas with very slight erosion, soil conservation practices should be expanded to secure the long-term sustainability of the production system, especially in agriculture and hazelnut areas.