Effects of Rangeland Restoration (Contour Furrows, and Mortar Stone Dam) on Soil Fertilization (Case Study: Silvana Region, West Azerbaijan Province, Iran)

The overgrazing and excessive utilization of rangelands has caused vegetation and soil degradation in many rangelands. In the rangeland management, the soil and vegetation elements, environmental factors and livestock should be considered as decision making agents. Various methods are applicable for the rangeland restoration as contour furrows and mortar stone dam. In order to evaluate the effects of restoration treatment on soil fertility parameters, this research was carried out in Rangelands of Silvana region, West Azerbaijan Province, Iran. Soil samples were taken based on a random method using six 100-m long transects in both treated and control sites. Soil samples were taken from the beginning, middle and end of each transect in both 0-30 cm and 30-60 cm depths. Nitrogen (N), Phosphorus (P) and Potassium (K) contents of soil samples were determined using Kjeldal, P-Olsen and flame photometer method, respectively. Differences between means of soil properties in the restoration and control treatments were compared by applying oneway ANOVA and SNK (P<0.05) test using SPSS18 software. The results showed significant differences between restoration and control for soil properties. N, P and K contents in mortar stone dam treatment in both depth soils were increased as compared to contour furrows and control. According to the results, there are significant differences among P, N and K concentrations in both mortar stone dam and contour furrow treatments between upper and lower soil layers. But, amount of K in the upper soil layer of contour furrow and mortar stone dam treatments was less than lower layer. It was concluded that the constriction of mortar stone dam in the studied area had led to positive impacts on soil fertilization. Overall, the results show that in Silvana region, rangeland improving is possible through applying the mechanical operation of mortar stone dam.