Investigation of the sensitivity of Hamoon-E- Saberi bed to desertification phenomenon

In recent decades, the decrease of the Helmand River water's feeding from Afghanistan and consequently desiccation of Hamoon Lake’s bed also, the continuity of the 120-day winds, has been resulted in frequency of dust storms originated from the bed of Hamoon International Wetland. These storms not only affect vast areas from Sistan plain to Zahedan also, include an extent of ​​about 200 square kilometers in Afghanistan and Pakistan in Iran border’s proximity. Based on investigation of satellite images of significant storms, the bed of Hamoon- E- Saberi with About 1000 square kilometers was identified as the largest and the main origin of dust particles in the Sistan plain, where land degradation caused by natural and human factors resulted in irreparable damages to the environment and human communities. Therefore, control and preventive measures in both planning and implementation phase require to determination and classification of the Hamoon bed susceptibility to desertification.

In order to determine the sensitivity of Hamoon Saberi bed to desertification phenomenon due to better compatibility of Madalus model indicators with the natural state of Sistan plain and available data, this comprehensive model was used to determine the sensitivity of work units in 2016. In this regard, geomorphological units were considered as working units and the status of five criteria of soil quality, vegetation quality, climate quality, management quality and erosion quality in those units were evaluated. Finally, by summarizing the scores, the sensitivity of the units to erosion was determined and its drawings were drawn in Arcgis software.

Results that is achieved by investigation criteria and sum up scores showed that by reducing the water level and finally complete wetland desiccation due to high range of evapotranspiration also soil quality reduction due to salt accumulation, land cover  has been decreased in the region. These changes accompanying with the presence of erosive winds in the region, has provided the conditions for land degradation and soil erosion, so that the QT3 unit with an average score of 1.83 in the wetland’s bed which is included areas such as Chong-e-Yekdast and Chong-e-Rig is located in class IV (very severe) while other work units with an average score of 1.48 are located in class III (severe).

Based on the results of the research, in planning to deal with wind erosion in Sistan plain and all desertification executive projects, QT3 work units should be given priority over other units due to their high sensitivity to desertification, So that in the management of wind erosion crisis, better results and more effectiveness can be achieved in a shorter period of time.