Investigation of Changes in Rangeland Soil Characteristics and its Functional Attributes Affected by Different Grazing Intensities (Case study: mountainous rangelands of Nesho, Mazandaran province)

Soil is a suitable place for vegetation and plant growth, and if this valuable wealth is not preserved, shortage of food, erosion and damage of natural resources will be occured. In this paper effects of different grazing intensities in reference area, key area (moderate grazing) and critical area (heavy grazing) on soil characteristics were investigated at mountainous rangelands of Nesho in Mazandaran province. Sampling was performed by a random-systematic strategy and sampling unit was linear transect. In each region, 3 transects of 50 m were settled at a distance of 50 m on the downstream slope. Five repeats of patches were randomly selected and for determination of three functional attributes including stability, infiltration and nutrient cycling, 11 soil surface indicators were scored according to the Landscape function analysis (LFA) method instructions. Along each transect at intervals of 10 m, a square 1×1 m2 plot was placed for measuring the canopy cover and soil sampling. The results of LFA method showed that the reference area had the highest stability, infiltration and nutrient cycling and also significant differences with moderate grazing and heavy grazing (p≤0.05). Results of the statistical analysis of the soil characteristics showed that the different grazing intensities had significant effects on the organic matter percentage, available potassium and soil surface resistance to penetration. By comparing the results obtained from the LFA method and analysis of the soil samples taken from the area, it was found that both methods were almost led to similar results, regarding the effect of grazing intensity on soil characteristics. Keywords