Effect of Grazing on Plant and Soil Parameters of Steppe Pastures on Mount Aragats, Armenia

Abstract

Steppe pastures are characteristic of the Armenian landscape and play an important role in supporting livelihoods and biodiversity conservation. The productivity and biodiversity of steppe pastures depend on grazing management, soil types, and climatic and topographical characteristics. As a whole, they form local small-scale sites. Our data on five study sites located on the southeast slope of Mt. Aragats summarized the impact of sites and grazing on canopy height; productivity; grass, legume, and forb biomass; nitrogen, phosphorus, and potassium concentrations; pH; and litter contents in the soil. Five grazed and ungrazed plots (ca. 600–800 m2) were established at each study site. Within each plot, two permanent 40 m long transects were installed. The canopy height was recorded in ungrazed and freely grazed plots. The aboveground biomass was cut at the soil surface from May to June; grouped into grass, legumes, and forbs; dried; and weighed. Soil samples were collected in every ungrazed and freely grazed plot. The results indicated that grazing decreased the plant parameters and nitrogen and litter content across all sites, while it had no effect on the phosphorus and potassium content or the pH. It seems that plant parameters, as well as soil parameters, were more affected by the management strategy than by the topographical and climatic features of the sites, as revealed via redundancy analysis. Our results suggest that it is important to introduce livestock rotation practices for sites with respect to the sustainable management of steppe pastures. This management strategy could ensure ecosystem services, high forage quality, and soil fertility.