Comparison of Litter and Aerial Organs Quality in Three Rangeland Species (Case study: Taleghan Rangelands)

The goal of this research is to compare the quality of litter and aerial organs in three rangeland species including Bromus tomentellus, Agropyron tauri and Psathyrostachys fragilis on the basis of nitrogen, phosphorous, potassium, carbon amounts and C/N proportion. After recognition of the species sites in Taleghan Watershed, litter and aerial organs of the mentioned species were collected. Sampling was done in key areas of each site along four transects using randomized-systematic method. Transect length was determined according to the area and variation of the key region.. Ten plots were placed along each transect and the dimensions of sampling plots were selected on the basis of species type and distribution using minimal area method. The obtained results of analysis of variance and comparison of means showed that B. tomentellus has maximum amounts of carbon and C/N proportion in its litter while P. fragilis has maximum amount of phosphorous and finally the maximum amount of nitrogen in litter is related to A. tauri. Meanwhile, P. fragilis showed maximum amounts of nitrogen, carbon and C/N proportion in its areal organs. The highest amounts of phosphorous and potassium are related to B. tomentellus. Totally A. tauri species showed the better condition than other species based on quality of litter and aerial organs.