Monitoring desertification processes using ecological indicators and providing management programs in arid regions of Iran

Desertification is a serious and perilous threat to natural ecosystems. Understanding the spatio-temporal characteristics of this process through the evaluation and monitoring of important indicators appears to be a challenging task. This research was carried out in arid regions of the northeast of Iran, with the objective of assessing desertification intensity and monitoring its progress over time. After collecting the basic data including climate, land use and land cover, roads of access, geology, demographics, pedology, land capability, and drainage network, desertification intensity was firstly assessed using the Iranian Model for Desertification Potential Assessment (IMDPA). Based on the results of the IMDPA model, important desertification indicators were selected and monitored in Geographic Information System (GIS). The results of the model were validated against ground-based data via the non-parametric Mann-Whitney test. The findings of desertification intensity assessment showed a moderate desertification intensity over approximately 41% of the central, northern and northwestern parts of the region. The agriculture criterion along with natural factors such as groundwater level fluctuations, salinity, and erosion had the greatest impact on the severity of desertification. Monitoring important and effective indices (over a 20-year period and in four 5-year intervals from 1995 to 2014) showed that drought, population growth, migration, land-use changes, vegetation degradation, soil erosion, groundwater level fluctuations, deterioration of groundwater quality and expansion of low-yield agricultural lands (2.75% increase in agricultural and residential lands over 2004-2014) led to an increased desertification intensity. Based on the status of desertification, a number of possible management programs were proposed for the study area. Accordingly, the implementation of some land degradation control programs such as replanting vegetation and compatible with salinity and drought are recommended to reduce desertification intensity in the study area.