EFFECTS OF DIFFERENT IMPROVEMENT TREATMENTS ON BOTANICAL COMPOSITION AND SEDIMENT MOVEMENT ON GRAZED AND ENCLOSED RANGE SITES

Abstract

This study was carried out on heavily grazed rangelands in Erzurum, during the years 2006-2009, for 4 years period. In this study, four treatments that included artificial pasture, oversowing, fertilization and control were applied on grazed and enclosed rangeland sites. A mixture of Crested wheatgrass (Agropyron cristatum), alfalfa (Medicago sativa) and smooth brome (Bromus inermis) was used for rangeland seeding. Ammonium sulfate and Triple Super Phosphate was applied on fertilization plots in sites grazed and enclosed site. Botanical composition was determined by line intercept methods. After each erosive rain event, the amount of soil (sediment) was determined in each plot. Across of four years, fertilization increased the grass proportion, decreased other species proportion and sediment yield in both sites. Under grazing, over sowing increased the grass proportion, and decreased other species proportion. Lower grass, higher legumes, higher other species proportion and higher sediment yield determined in the third year compared to other years in both sites. The enclosed site had higher grass, lower legumes, other species proportion and sediment yield than the grazed one. Results of this study showed fertilization and over sowing treatment can be effective for soil protection in enclosed and grazed rangelands, similar to this study area. Also, combined with short term enclosure treatment the other improvement treatments can recommend for rangeland restoration and soil protection.