Study of Grazing Intensity on Organic Matter and Soil Nitrogen Changes at GardanehZanbouri Rangeland of Arsanjan, Iran

Presence of livestock as an integral component in rangeland ecosystems could be effective as different ways on grassland soil. Assessing the effects of grazing for finding of appropriation management policy and adopting of appropriate strategy is necessary for grazing in the rangelands of country. This is very important especially in arid and semiarid ranges.To investigate of grazing intensity effect on organic matter and soil nitrogen changes at 3 zones: The reference zone, Critical zone and key zone at Gardaneh Zanbouri rangeland of Arsanjan, soil sampling was carried out as systematic randomly and from two horizons from 0 to 15 cm and from 15 to 30 cm. At every horizon, 5 samples were sampling and organic carbon factors, organic matter percentage, the ratio of carbon to nitrogen and the total of nitrogen were measured. Data analysis was carried out by SPSS software and comparing of mean values for each factor and between areas with different grazing intensity was done by Tukey test. The results of two- way analysis and Tukey test showed that there is not any significant difference between critical and reference zones as studied factors. But, at key zone the values of organic carbon, organic matter and nitrogen percentage is lesser than critical and reference zones, while the value of C/N is greater than the other two zones.