Drought and Desertification in Iran

Abstract

Iran has different climatic and geographical zones (mountainous and desert areas), mostly arid and semi-arid, which are suffering from land degradation. Desertification as a land degradation process in Iran is created by natural and anthropogenic driving forces. Meteorological drought is a major natural driving force of desertification and occurs due to the extended periods of low precipitation. Scarcity of water, as well as the excessive use of water resources, mainly for agriculture, creates negative water balances and changes in plant cover, and accelerates desertification. Despite various political measures having been taken in the past, desertification is still a serious environmental problem in many regions in Iran. In this study, drought and aridity indices derived from long-term temperature and precipitation data were used in order to show long-term drought occurrence in different climatic zones in Iran. The results indicated the occurrence of severe and extremely severe meteorological droughts in recent decades in the areas studied. Moreover, the De Martonne Aridity Index (IDM) and precipitation variability index (PVI) showed an ongoing negative trend on the basis of long-term data and the conducted regression analysis. Rapid population growth, soil salinization, and poor water resource management are also considered as the main anthropogenic drivers. The percentage of the rural population in Iran is decreasing and the urban area is growing fast. Since the 1970s, the usage of groundwater in Iran has increased around fourfold and the average annual decrease in the groundwater table has been around 0.51 m. The results of the study provide a better ex-post and ex-ante understanding of the occurrence of droughts as key driving forces of the desertification in Iran. Additionally, they can enable policymakers to prepare proper regional-based strategic planning in the future. Desertification cannot be stopped or managed completely, but could be mitigated by the adoption of some proposed sustainable land management strategies.

Application of TRMM Precipitation Data to Evaluate Drought and Its Effects on Water Resources Instability

“…Roodposhti et al [27], using support vector machine algorithm, enhanced vegetation index (EVI), and SPI showed that in the duration of 1978-2008, the most severe drought was in 2008 in the study area, which is consistent with the results presented in Figure 8. Bazrafshan [28] and Emadodin et al [29] showed that, in recent years, at most stations in Iran, including stations in the Kermanshah, the severity of the drought has become more severe with time, which is consistent with the results of this study.…”

Climate Change Effects on Temperate Grassland and Its Implication for Forage Production: A Case Study from Northern Germany

“…Changes in precipitation and seasonal water regimes can result in increased drought, thereby greatly affecting productivity [3]. Anthropogenic climate change, attributed to the greatly increased greenhouse gas (GHG) emissions since the 19th century, has been identified as a cause of increased frequency and severity of droughts [4,5]. Drought is a major contributing factor to land degradation [6], a process that is further accelerated by unsustainable land-use practices such as overgrazing and urbanization [7][8][9][10][11][12], and it has serious potential consequences for global food security.…”

A perspective on the potential of using marine organic fertilizers for the sustainable management of coastal ecosystem services

“…The overuse of soil as a consequence of inappropriate management to meet increasing food demand, including intensive use of fertilizers and pesticides and monoculture cropping, has had direct and adverse effects on soil ecosystem functions and services. Therefore, population growth and soil degradation are often closely linked (Emadodin and Bork 2012;Emadodin et al 2019). Moreover, the conversion of woodland and rangeland into agricultural land for crop and biofuel production has accelerated and triggered additional environmental loads (Millennium Ecosystem Assessment 2005;Emadodin et al 2009;Lobell et al 2011;Bedunah and Angerer 2012;Taube et al 2014;Lal 2015;Vimal et al 2017).…”