Environmental challenges and drought hazard assessment of Hamoun Desert Lake in Sistan region, Iran, based on the time series of satellite imagery

Abstract

The Sistan area is located in the east of Iran, enclosure to Afghanistan border. It is a densely populated enclave in the scarcely populated arid area of the eastern part of Iran, where the life strongly depends on the shallow water of Hamoun Lake and wetlands in the delta of the Helmand River flows from the Hindukush Mountains in western Afghanistan. As the water resources are scarce in this arid region, the availability of freshwater in Hamoun Lake has caused many socioeconomic and environmental effects in study area during several years. Various categories of socioeconomic criteria have been defined that are influenced by the Hamoun wetland, namely employment, economic value of fish catch, reeds harvest and birds hunt, food supplying and its influence on the microclimate of the region and the severity of the sandstorms, health and finally provision of recreational opportunities in the region. On the other hand, the high evaporation rates in a very dry region and climatic fluctuations make very vulnerable ecosystem, causing several environmental challenges into human activities. Prolonged droughts due to decrease in annual rainfall in the Hirmand watershed based on climate change in the last decade have been recorded in this environmental hazardous area. Drying up of Hamoun Lake and dead reed system in the wetlands was monitored in the present study using the time series of satellite imagery. The lifelessness of Hamoun Lake has caused several environmental effects such as sandstorm and dust hazard, destroying vegetation, vanishing crop production, damage to fish and bird habitat, extensively decreasing reeds harvesting, reducing livestock and increasing wildlife death rates, increasing air pollution and consequently health problems, salty soil movement over the agriculture fields, etc., which have been identified as the outcome of this research.