Land-use change in the Zagros forests and its impact on soil carbon sequestration

In this study, the amount of organic carbon in the soil of sacred grove lands was examined to determine the Zagros oak forests’ capacity in carbon sequestration. For this purpose, the amount of soil organic carbon (SOC) storage in the Zagros forest and some of their most important characteristics (soil bulk density (BD), %C, SOC, %N, C/N, pH, electrical conductivity (EC)) in four land uses (sacred groves, silvopastoral lands, destroyed forest areas and agricultural lands) were examined and compared. In all four land uses, a total of 200 soil samples at two depths were prepared and analyzed. The results showed that different land uses have a significant effect on the amount of each of the mentioned variables (α=%1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\alpha = \% 1$$\end{document}). Furthermore, at the two studied depths, there was a significant difference in the amount of each of the variables studied except in soil bulk density (BD). SOC rate in sacred groves and agricultural lands had the highest and lowest values, respectively (84.37 and 23.3 t/ha). At the first depth of sacred groves alone, the SOC rate was approximately 1.8 times that of the total of silvopastoral areas, twice the rate of that in destroyed forest areas and more than three times the SOC rate in agricultural lands. At both examined depths, sacred groves soil samples had the highest values of %C, %N, N/C and EC and the lowest bulk density. According to the results, forest ecosystems which are protected against human interference play an important role in the long-term storage of carbon in the soil.