Document Type : Research Paper
The aim of this study was to assess the conversion of forest to vineyard on different physical pools of organic matter in Zrebar Lake watershed. Soil samples were collected from the two major land use types including forest and vineyard land at 0-30; 30-60, and 60-90-cm depths. In each land use, different SOC fractions were measured. According to the results of size fractionation of organic carbon in 0-30-cm layer, the highest and lowest amount of sand sized fraction organic carbon was obtained in forest and vineyard land use; respectively. The amount of sand sized fraction SOC was decreased with depth. In the forest land the content of light fraction in each depths was more relative to vineyard. The light and sand sized fractions in surface layers were showed high response to management changes. Organic carbon storage in the surface layer has been more than other depths. It is proposed to apply special management in surface layers of soils to mitigate the loss of different SOC fractions.