Soil erosion and its trend in Iran by comparing several case studies

The Soil erosion in Iran is considered as one of the serious impacts and threats to the environment.According to the latest official statistics, ۲ billion tons of soil is eroded annually in Iran. Soil erosion, due tothe topographic conditions of the region and the type of land use and resource utilization, has an increasingtrend and ongoing measures to reduce erosion are very small. According to the United Nations, global soilerosion has increased to ۲۴ billion tons per year, and the world's fertile soil is being destroyed. Theworrying and important point is that one twelfth of the total soil erosion in the world, i.e. about ۲ billiontons, occurs in Iran alone; this is while Iran has only one percent of the world's land. In other words, therate of soil erosion in Iran is ۸ times the global average. On the other hand, climate change, uncontrolledhuman exploitation of nature, destruction of vegetation due to overgrazing, traditional and unprincipledagriculture, deforestation, water shortage and Iran's location on the erosion belt of the world are otherfactors that aggravate soil erosion. They are considered in the country. In this study, a comparison has beenmade between erosion statuses in three regions over a period of about ten years. For this purpose, inaddition to field visits, the MPSIAC experimental model and sedimentological and geophysical studieshave been used. The results show that in all three areas the erosion is more advanced and has neverstopped. In all three areas, the climate has become drier, vegetation has declined, and runoff productionhas become easier. Also, land use change has increased lands prone to erosion and this trend is expandingrapidly.