Suitability assessment of saline winter rangelands for sheep grazing (Case study: Gomishan Plain)

Range suitability assessment for different objectives is along with management principles and guarantees sustainable development. A considerable area of Golestan Province plains is covered with halophytes, grazed by different livestock including sheep. A study was done to assess the suitability of saline winter rangelands with dominant species of Halocnemum strobilaceum and Aleuropus lagopoides for sheep grazing. The F.A.O method in GIS environment was used in this research for Gomishan Plain, Golestan province, Iran. In the method, three criteria of vegetation, water and soil erodibility were used as the sub-models and constituted the final model components. For vegetation sub-model, vegetation types, cover percentage, forage production, range condition and trend and range capacity were determined. Distance from water resources, water quantity and quality were determined for water sub-model. For the soil erodiblity sub-model evaluated by the EPM model, slope, rock and soil sensitivity to erosion were determined. The final model of range suitability for sheep grazing revealed that 38.69 and 61.31 percent of the region were classified as low suitability and no suitability, respectively. Among all factors determined in sub-models, the distance from water resource was the most limiting factor for sheep grazing and forage production was the most reducing factor of range suitability. Finally, utilization of rangelands in the region could be improved by reducing grazing intensity and implementing range restoration practices.