Abstract

In this research, was investigated the effect of grazing intensities on carbon and nitrogen allocation in aerial and belowground biomass of Artemisia austriaca in summer rangelands of Darvishchae (including Alvares, Aldeshin and Asbmarz villages) at southern slope of Sabalan. The study areas based on grazing rate, rangeland condition, previous researches and department of Natural Resources and field survey in three grazing intensity low, medium and heavy was selected. Sampled in each grazing intensity, from vegetation and soil with randomized-systematic method on 3 transects parallel with the length of 200 meters and plot 1×1 m2 was carried out at intervals of 50 meters. Biomass was determined using cut and weighting method. After digging profiles at the base of the plant, roots were harvested. Then, allocation in aerial and underground plant was determined. The comparisonof allocation in plant was conducted using analysis of variance (ANOVA) and Tukey's test was performed to examine the differences between means. Results showed the effect of different grazing intensities (mostly sheep of Moghani breed) on biomass of A. austriaca was significant. Results of compare mean showed that the greatest amount of nitrogen allocation in the aerial biomass of A. austriaca (2.2 mg/kg) was observed in the moderate grazing intensity. Moreover, the greatest amount of carbon allocation in the roots of A. austriaca (22 mg/kg) was occurred in the moderate grazing intensity. In general, attention to effects of grazing different intensities on vegetation factors such as carbon and nitrogen allocation, is essential for rangelands correct management and protection.