نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه اقتصاد کشاورزی، دانشکده اقتصاد و توسعه کشاورزی، دانشگاه تهران، کرج، ایران
2 گروه اقتصاد کشاورزی، دانشکده اقتصاد و توسعه کشاورزی، دانشگاه تهران، کرج، ایران.
چکیده
کلیدواژهها
Extended Abstract
Objectives
Water is an essential element for human survival without which human life is inconceivable. Iran is located in an area of climate cycle of the northern hemisphere in which the air masses subside. That is why more than two-thirds of this country has arid and semi-arid climates. Inappropriate temporal- spatial precipitation distribution is one of the climatic features of Iran. Iran's share of the world's population is 1.3% and of freshwater resources only 0.2%. The major challenges facing the water resources that cause unsustainability of the drainage basins include unsuitable decrease in renewable water resources, increase of water pollutants, groundwater over-extraction (due to limited available surface water resources), uneven precipitation distribution and non-conformity of urbanization patterns and residential centers with respect to water resources and crop production methods (from the perspective of eco-friendliness). Therefore, a proper understanding of the impact of human activities that manifested in the processes and mechanisms we observe in a drainage basin can help us conserve water resources and contribute to its sustainability. In this regard, integrated water-resource management has been interpreted as the operational method of water-resource sustainability. Therefore, seeking to identify factors impacting non-sustainability, the present research assesses the current situation in the drainage basins of Iran from this perspective.
Methods
For this purpose, social, economic and environmental information and water poverty index (WPI) were used to analyze the conditions of the drainage basins in the country with respect to the five components of resources, access, capacity, consumption, and the environment. Statistical methods were then employed to rank the drainage basins in the country in 2016 in terms of the mentioned components. Since the economic, social and environmental data collection on the drainage basin scale is costly and time consuming, and given the share each county has in the rescaled drainage basins, the data were extracted on the administrative (political boundaries) scale.
Results
The results showed that the average value of the WPI in all the drainage basins was 43.73 with its lowest and highest values recorded in the Sefidrood Drainage basin (57.58) and the Kavir Drainage Basin in Anjir (27.55). Investigation of the five WPI components in the drainage basins also indicated that the resources and consumption components with 19.24 and 36.86 had the lowest values among the components. This demonstrated the poor conditions of the drainage basins in the country in terms of the resource component and in relation to the high share that water consumption had in the agricultural sector regarding unsustainability of the drainage basins. The access component had the third place with an average of 46.60 which indicated inadequate access of the sectors with water demands to wastewater discharge and treatment systems. Moreover, based on the ranking in the WPI, the Kavir in Anjir drainage basin in Southern Baluchistan and the Hamun-e- Jazmourian, the Gharasoo, the Gorgan, the Kal, the Mehran and the Bandar Abbas-Sedij drainage basins were unsustainable, and the Greater Sefidrood, the West Border, the Lake Urmia, and the Greater Karun drainage basins lacked water stress and enjoyed total water sustainability. The results of the correlation matrix indicating the correlations between the WPI and its components revealed that all five components, except for the capacity component, had significant positive correlations with the WPI. Therefore, it can be said that increased access to water resources will improve the ability and efficiency of the management system and raise the per capita domestic water consumption in the drainage basins. In addition, increased ability and efficiency of the water-resource management system led to savings in water consumption.
Discussion
Based on the results, it is suggested that, in line with the establishment of integrated water resources management, holistic approaches be used to evaluate the situation of water resources in the various regions. Considering the inappropriate conditions of the resources component in the drainage basins, it is also recommended that the government supervise the consumption volumes of the limited water resources and take steps toward integrated water-resource management by promoting water consumption savings. Due to the large share that the consumption component has in the unsustainable situation of the drainage basins, it is suggested that increases in area dedicated to irrigated agriculture be limited in the drainage basins that face water stress. Moreover, because of the significant positive correlation between the consumption component and the WPI, one can expect improvement in water sustainability through promoting savings in water consumption and reducing acreage of land under cultivation of irrigated crops. Regarding the components of capacity, access and the environment, there are positive and significant relationship between them and the WPI. Therefore, it is recommended that the government implement policies to increase social capacity, equipment and facilities required for providing water resources and water treatment plants and to reduce fertilizer application in the country's drainage basins.
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