Assessment of changes in soil degradation coefficient in Godrahav watershed

ASSESSMENT OF CHANGES IN SOIL DEGRADATION COEFFICIENT IN GODRAHAV WATERSHED Soil degradation index is a quantitative form of expression of soil degradation, which is defined as the fact that the soil changes so much that it cannot perform its function within the ecosystem due to natural or human-induced reasons. This study was carried out to determine the degradation index values of the soils in the Godrahav basin, in order to make terrestrial variability analyses and to create forecast maps. In the first stage of the study, after the literature review, the study area was divided into 500x500m transects with the help of ArcGIS software and 137 disturbed and undisturbed soil samples were taken from 0-10 cm depth at the intersections of these transects. Following the completion of the necessary pre-treatments, soil texture, aggregate stability, aggregation rate, mean weight diameter, dispersion rate, bulk density, porosity, field capacity, permanent wilting point, organic matter content, pH, electrical conductivity (EC) were analyzed. In the second stage of the study, mapping of the topographic features (slope, elevation, aspect), and land use, and (forest canopy density) of the basin and the land use was carried out using ArcGIS software. Semivariograms were calculated to determine the local dependency of the properties and models that define the relations in the most appropriate way were created. The degradation index values were calculated for each sampling point using two different weighting methods. As a result of variance analysis, it was determined that there was no statistically difference between the distortion index values in terms of methods. When the scatter maps were analyzed, it was determined that the soil properties and the degradation index value differ according to the land use, closure rate and the plot condition of the land, but they do not show a relation with the slope. The results of the study are thought to provide useful information to practitioners in integrated watershed management studies.