Drought Risk Analysis of Dazhen Irrigated Area
|School||Changsha University of Science and Technology|
|Course||Hydrology and Water Resources|
|Keywords||Drought Risk Risk identification Supply and demand analysis Drought index Risk estimation|
Flooding, drought and water environment deterioration are the three major water problems that china must face with in the 21st century. The drought and water shortage in China mainly is the shortage of water resources and water shortage caused by water pollution, and drought will become the most important factor which will gradually restrict the development of economic and the society in China.Drought and flooding are both the natural disasters that take great harm to human beings. Because of the suddenness of flooding, it can be detected easily. But the occurrence and development process of drought is relatively slow, and there were no clear signs before the disaster comes. Therefore, human beings are not aware of the impact of drought untill the disaster had already come, so the starting and ending time is difficultly defined. Compared to the flooding, drought has its own characteristics, such as long duration, large impact range and significant influence after drought. Globally speaking, the number of drought only make up about 5% of all the number of natural disasters, but the loss of drought shared 30% of all natural disaster losses, ranking first in natural disaster losses.Drought is a natural phenomena caused by caused by imbalance of water and decreased rainfall, natural phenomena. Drought is the first disaster against agricultural production, it affects the distribution, growth, output and quality of crops, and is the important factor that determine agricultural development. Agriculture is the foundation of our national economy, the development of agriculture has crucial influence over economic development and social stability of our country. Thus, the drought evaluation of large-scale irrigation district drought in our evaluation of large-scale irrigation to improve food production played a promoting role in the process of improving the grain output of the large-scale irrigation district greatly.With the frequent occurrence of drought, and the extension of drought territory to the humid areas (for example: in 2010 five provincess including Yunnan, Guangxi, Guizhou, Sichuan and Chongqing suffered from drought, which caused nearly a million hectares of arable land with little or no production, and caused the ecnomic losses worty of 170 billion yuan in only Yunnan province), people is becoming aware of the weakness that crisis management after drought response to drought slowly. In order to reduce the drought damage to a greater extent, human beings began to shift the work focus to monitoring and prevention of the drought before drought happens, which is called drought risk management. The practice and theory risk management began in the U.S. insurance industry around 1930’s, developed a management science in the 1950’s. Drought risk management is such a management model, which establish implementation of drought before the drought happens, carry out real-time monitoring to the drought , and adopt measures according to the different drought stages .The practice and theory risk management began in the U.S. insurance industry around 1930’s, developed a management science in the 1950’s. Drought risk management is such a management model, which establish implementation of drought before the drought happens, carry out real-time monitoring to the drought , and adopt measures according to the different drought stages .In this paper, we analyzed the characteristics and law of grought of Dazhen irrigaed area in Hunan Province, and found the drought causes and development law of Dazhen irrigatied area. The introduction of the concept of risk analysis to the large-scale irrigated area in Hunan Province is to establish of drought plan before drought happened, the development of real-time drought monitoring, according to the different stages of drought mitigation measures on drought disaster assessment model.This article is divided into two parts- risk analysis and risk assessment of drought, to study the focus of agricultural drought based on the drought study of Southern irrigation district, its aim is to analyse the law of the drought in the south irrigation area and discuss drought management pattern that is fit for the south region. This article introduces the concept of risk management to the large-scale irrigation district, and put the concept of drought risk management. drought risk management is a scientific management pattern. On the basis of grasping the temporal and spatial evolution of drought and fully understand the formation mechanism of drought disaster, we use a multi-factor drought index system for early identification of drought.