Vulnerability assessment to Drought in Various Provinces, approach towards risk management in the country

The water crisis is one of the main challenges of the current century. Drought is one of the most costly natural disasters in Iran. During the past 40 years, our country has experienced 27 droughts. It seems a necessary step to deal with the consequences of drought and reducing its effects, thorough understanding and knowledge of each region's vulnerability, which is neglected in our country, unfortunately. It is necessary to study the influencing factors in determining vulnerability and makes it visible. On the other hand, due to the continuing drought conditions intensified in recent years and its impact on different economic sectors, especially the agricultural sector in the country need to assess vulnerability to drought in the country will double.
Fuzzy AHP method based on the concept of fuzzy sets introduced by LotfeiZadeh. There are several ways to use fuzzy theory and hierarchical structure proposed merger. Cheng in 1996 suggested a new approach to solve problems using Fuzzy AHP calibration values within the membership and (TFNs). Extent Analysis Method proposed by Chang is one of the common ways to solve problems. In this study, we developed a method based on fuzzy analytic hierarchy Chang that has been developed by Zhu et al. and Van Alhag.
Vulnerability to drought conditions is determined by factors such as economic, social and physical sensitivity to the damaging effects of drought increases. This study is designed in the hierarchy. The purpose of this study is assessing the vulnerability of the country to drought. Vulnerability of this study includes economic vulnerability, social vulnerability and physical vulnerability. Economic vulnerability to drought indicates that the economy is vulnerable to external shocks due to drought and the inability of the economy to withstand the effects of the event and recover the situation. Social vulnerability determines the capacity to deal with drought in the community and reflect the effects of drought on people's ability to cope with the event. The physical vulnerability is related to the characteristics and the structure of society, infrastructure and services that are the result of the damage caused by drought. In the present study, the economic dimension of vulnerability, including GDP per capita, value added in agriculture, value added in industry and the impact of drought on the GDP. Under the criteria of social vulnerability, population density, population growth, the rate of literacy, vulnerable populations, the costs of health and safety and the impact of drought on employment were considered. The physical dimensions of vulnerability include the rate of irrigated land and road density since the objective of this study was to assess vulnerability to drought in various provinces of the country, the required data for all provinces except for Alborz province was collected in 1391 from intelligence sources. To determine the importance of different dimensions of vulnerability as well as the sub-phase in each dimension, the questionnaire was used for paired comparisons. As for the tens of experts, specialists and professionals who have expertise using the Delphi method is incorporated. In general, the importance of physical vulnerability is more than economic and social vulnerability. On the other hand, according to the results the economic and social vulnerability is important, too. The results of this study showed that the importance of the physical vulnerability was more than the economic and social vulnerability and economic vulnerability and social importance were the same. In the economic vulnerability sub-criteria of per capita GDP, in the social vulnerability sub-criteria of population density and in the physical vulnerability sub-criteria of road density have the most importance. These findings may reflect the fact that when drought occurs, access to infrastructure, services and markets can considerably reduce the harmful effects of drought. According to the results, Semnan, Tehran and Gilan provinces jointly are economically vulnerable. On the other hand, in terms of criteria for social vulnerability, provinces of Fars, Khuzestan and Gilan were the most social vulnerable and Isfahan, Kermanshah and Ilam are the least vulnerable. Also, according to the results the province of Khuzestan, Fars and Khorasan were the most; and Yazd, Bushehr and Kohgiluyeh Boyer were the least physical vulnerability.
In this study, in order to assess vulnerability to drought in various provinces, , after determining the hierarchy and collect relevant data, the importance of each criteria and sub-criteria were determined. In order to determine the importance of different aspects of vulnerability (the economic, social and physical) Fuzzy AHP method was used in each dimension. According to the results of this study, the province of Khuzestan, Fars and Khorasan are the most and Yazd, Bushehr and Kohgiluyeh Boyer were the least physical vulnerability. Since different provinces have significant differences in vulnerability to drought and vulnerability in various aspects of economic, social and physical, in order to achieve drought management based on risk management, recommended in policy and planning make attention the effects of drought in the various provinces.