Determination of soil quality index for sunflower cultivated soils with SMAF model. Case study; Tokat-Zile, Belpınar village

There are many approaches to improve and disseminate the methods used to identify and evaluate changes in soil functions of soil management practices. One of them is the SMAF (Soil Management Assessment Framework) model. The aim of this study to determine physical, chemical and biological soil quality index values and total soil quality characteristics of cultivated soils for sunflower in agricultural areas of Tokat-Zile Plain which has semi-arid terrestrial ecosystems by using SMAF (Soil Management Assessment Framework) model. For this purpose, 175 soil samples were collected from surface soil (0-30 cm) in the study area which covers about 1667 ha. SMAF model includes 13 indicators such as aggregate stability, available water content, water-filled pore volume, total organic carbon, pH, electrical conductivity, the sodium adsorption ratio (SAR), microbial biomass carbon, available phosphorus, βeta-Glukosidaz enzyme activity, total nitrogen and available potassium as physical, chemical and biological indicators. According to obtained results, it is determined that while the chemical quality index of the soils cultivated for sunflower was in the low class, biological quality of them was found in high quality class. In addition, physical and total soil quality indexes were found as moderate and high quality class. Distribution of physical, chemical, biological and total soil quality index show higher value in the sought part of the research area, when it is compared with the other parts of the study area.