Health assessment of agro-ecosystems in Birjand region

In order to evaluate the health of agro-ecosystems in the Birjand region during the yearsof 1991-2011, a studywas conducted between 2011 and 2012. In this study, 38 indices were chosen as health indicators, all of whichwere calculated according to their scientific and quantitative definitions. In order to fitthe relevant equations and observe the variation process, regression analysis was used. At the next step, the relevant positive and negative indices (from to -3) were determined taking into account the positive or negative states of each indicator and the degree of its effect on agro-ecosystem health. Also, after standardizing the datum, the relevant indices have been applied for setting the datum at between zero and one. As a result, the total health index for each year was determined through an algebraic summation of the total indicators’ scores. Finally, the total health index of agroecosystems throughout the 21-year period was calculated from the algebraic summation of the scores finallyachieved. In order to determine the level of quality of the total health index during these 21 years, qualitative classification of the scores was conducted. Based on the findings, the total health index of agro-ecosystems in the Birjand region, obtained from the summation of total scores of 38 indicators during the study years, was placed in a weak health ranking with a score of .92. The health index showed a decreasing trend from the beginning of the study in 1988, when it was closer to the frontier of health and, from then on up to the end of the period, when it reached to the level of an absence of health. The most positive and negative among all the indicators affecting the total health index, were the indicator for agricultural co-operatives and the indicator for damage to agricultural products at .60 and -33.67, respectively.