Investigation of the relationship between production and biodiversity in steppe rangelands of Isfahan province

Biodiversity is one of the important concepts in ecology and vegetation management, and plays an important role in the health, production, and evaluation of ecosystems. Species diversity is a major part of biodiversity and one of the most important parameters of ecosystem changes. In this research, the data of the rangeland evaluation different climate zones of Isfahan province were used in five range sites of Alavijeh, Charmshahr, Khondab, Kalahroud and Mouteh to study the variations of the diversity and richness of species with production in the steppe rangelands. The sampling was done on random -systematic and the density and percent of vegetation conopy of each species along the transects using constant plots and production are also estimated by double measurement using the coating. The diversity numerical indices were calculated using Excel, PAST, Ecological Methodology and PRIMER softwares. In order to investigate the relationship and presentation of the model between species diversity indices with parameters (production, density, and canopy cover percentage) from pearson correlation analysis and multivariate regression analysis were used in spss software. The results from the correlation analysis mirror the significant correlation between some species diversity indices and vegetation parameters. The results from the correlation analysis show mirror the significant correlation between some species diversity indices and plant cover parameters. The correlation coefficient of different indices of biodiversity in different regions with density of 0.76 to 0.98, vegetation percentage is 0.74 to 0.92 and production is 0.71 to 0.92. Also, the results from the multivariate regression analysis reflect the effect of the density, vegetation of herbaceous broadleaf (%), and total Coverage on the production. In the rangelands under study, Menhinickchr('39')s richness index was able to justify 13.1% of the changes of herbaceous broadleaf productions. Among the species diversity indices, Hill’s index N2, Simpson index, and McIntosh index and among the evenness indices, Camargochr('39')s index and Shannon-Wiener’s index had the most connection with production and they can justify its changes.