ارزيابي پهنه بندي شاخص شوري زمين شناسي مؤثر بر تخريب آب و خاك (بررسي موردي: حوزه آبخيز حبله رود)

Zonation of the Effective Geologic Salinity Index of Water and Land Degradation (Case Study: Hableh-Rood Drainage Basin)

Land degradation and desertification in arid and semi-arid regions occur due to natural factors and human influences such as overgrazing, improper landuse and exploitation of groundwater resource. Salinity criteria might be due to geological conditions of the area. Due to the litologic diversity and the presence of saline formations including diapers, Hablehrood Drainage Basin was chosen for studying the effect of geology on salinization of the area. The objective of this research is to study the salinity index with geologic origin which is effective in degradation of some parts of Hablehrood Drainage Basin. First, by overlaying slope, land use and geologic maps of the area, working unit map was prepared as homogenous map of the area. Then sampling was performed randomly and top soil at the depth of 0-10 cm was sampled in each working unit. Then, chemical analyses were performed on each sample in the laboratory. It resulted the salinity map of the area having six classes and the relationship between salinity and geologic formations and rocks was then determined. The results showed that the order of formation having salinity problem from high to low are as follow: Lower Red Formation, Upper Red Formation, Qom Formation and Kond Formation.