The effect of mining on changes in diversity, richness and vegetation structure of rangelands (Case study Copper Mine in Dareh Zereshk, Yazd province, Iran)

Mining has increased dramatically in recent years and, destroys natural resources and the environment. This study was carried out to investigate the effect of mining activities on diversity, richness, evenness and structure of vegetation cover in rangelands around copper mine of Dareh Zereshk located in Yazd province. Three sampling sites (0-200), (200-500) and (500-1000) meters far from the mine were selected for the study. Then, on each site, 3 transects of 200 m with 50 m apart, Were affected Perpendicular to the slope direction. In each plot, canopy cover percentage and density of plant species of existing species was recorded. The results of variance analysis for different indicators of species diversity, richness and evenness showed that all indicators had significant differences in the three study areas (p <0.05). So that the richness and diversity indices increased with distance from the mine and instead the evenness index was higher near the mine. Also, increasing the distance from the mine significantly increased the percentage of canopy cover of Asteraceae, Fabaceae, Poaceae, Chenopodiaceae and Lamiaceae(p <0.05). In addition, some structure of vegetation cover such as geophyte, chamophyte, hemicryptophyte, shrubs, grasses and perennials were significantly reduced near the mine. In general, the results showed that mining operations had a significant effect on the structure of vegetation in the area and reduced plant diversity. Therefore, it is necessary to pay attention to the pasture damage in the rangeland.