DETERMINING THE FACTORS AFFECTING RANGELAND SUITABILITY FOR LIVESTOCK AND WILDLIFE GRAZING

Rangelands have a significant role in the supply of forage for grazing livestock and wildlife.Therefore, it is necessary to evaluate the rangeland grazing suitability for livestock and wildlife.In this study, the Jeliz Jand Basin was selected.This basin, with an area of 16210.44 ha, lies between longitudes 52° 36' to 50° 52' E and latitudes 35° 44' to 35° 57' N. It is located in north of Firouzkooh city, Tehran Province, Iran, and has a cold semi-arid climate.Data integration was carried out according to the FAO method (1991) using GIS on a scale of 1: 20000.For livestock and wildlife grazing, information on physical factors and vegetation in the form of three sub-models including forage production, water resources and soil sensitivity to erosion was integrated and the final model of rangeland suitability was produced.According to the results, the range suitability for sheep and goats grazing in the study area was determined to be moderate (S2) for 11.3% (1560.3ha), low (S3) for 80.5% (11148 ha) and unsuitable (N) for 8.3% (1146.5 ha), respectively.Rangeland suitability for cattle grazing in the study area was determined to be high (S1) for 1.7% (228.9 ha), moderate (S2) for 3.6% (498.6%),low (S3) for 0.8% (111 ha) and unsuitable (N) for cattle grazing was 93.9% (13016.9ha), respectively.Also, about 1491 ha of rangelands were low suitable for wildlife grazing.It is worth mentioning that slope percentage, vegetation composition (presence of class II and III species) and low vegetation cover because of overgrazing and the past land-use conversions were the most important factors limiting rangeland suitability in this Basin.However, it is necessary to reduce the population of cattle and goat, and grazing program should be set up and continued with sheep according to the principles of range management.