Determination the most important variations in plant traits related to livestock grazing using multivariate statistical methods in Baladeh-Noor rangeland, Mazandaran Province, Iran

Abstract

Animal grazing affect rangelands ecosystems by changing dimensional characteristics. The aim of this study is to determine the most important variations on plant traits in response to the livestock grazing in Baladeh-Noor rangelands located Mazandaran province in North of Iran. Various plant characteristics were measured in moderate and high grazing intensity and exclosure for three key and palatable species of Artemisia aucheri, Astragalus sp and Bromus tomentellus. In order to detect plant properties variation in three sites (exclosure, moderate grazing and critical grazing) and to determine their sensibility, the DCA and PCA analysis were used. According PCA analysis, the most changes of grazing effect in first principal component is related to the crown and basal large diameter, underground biomass and root. It was observed significant changes in five plant properties. Also, the results showed that 92.98% of changes are described by first and second axes and the most of Eigen value are crown and basal large diameter and root with 0.982, 0.977 and 0.968 respectively. As a result, the correct management of grazing according to the potential of soil and vegetation cover of each site could improve the condition of rangelands and produce the constant and dominant forages and livestock.