Study On The Risk Assessment Of Regional Agricultural Drought

In recent years, as global warming and increasing water demand, the droughtfrequency, drought intensity and drought extent in our country have increasedsignificantly, which poses a serious threat to country’s food security, water supplysecurity and ecological security. The drought has become one of the major naturaldisasters that restrict the sustainable development of economy and society in China.However, compared with the basic research of flood and flood management system,the basic research of drought and drought management is still quite weak. At this stage,strengthening basic research of drought to transform drought crisis management modeto risk management model is the key to enhance the level of drought control anddisaster reduction in China. As the core content of drought risk management, droughtrisk assessment plays an important role in drought relief practice. Whether from theresearch level or application level, to establish a more complete theory of drought riskassessment and technical methodology has important theoretical and practical value.From the above, based on the study of the basic theory and methods of drought riskassessment, the theory and methodology of regional agricultural drought riskassessment are put forward, then some application researches are made in this paper.The main results obtained are as follows:(1)Based on the summary of related researchs about drought risk, the relationshipbetween drought and drought disaster is analyzed, then the concept, connotation andcharacteristics of drought risk are specified. After that, the basic pattern of drought riskassessment is expounded. According to the basic theory of drought risk assessment,the basic theory of agricultural drought risk assessment is built. The content ofagricultural drought risk assessment is specified and the model of agricultural droughtrisk assessment is established. On this basis, a relatively systematic and scientifictheoretical basis of agricultural drought risk assessment is formed.(2)A model of agricultural drought risk assessment which is based on causes of agriculturaldrought risk is built, and specific methods of the model are refined. The methodology ofregional agricultural drought risk assessment contained of key technologies such asdrought frequency and return period computation, capacity of drought resistanceanalysis, agricultural drought loss assessment is established. According to thecharacteristics of agricultural drought risk, the application mode that can be described as agricultural drought risk atlas consisted of agricultural drought hazard maps,agricultural drought vulnerability maps and agricultural drought risk curves isestablished, which can characterize the spatial and temporal distribution as well asseverity of regional agricultural drought risk.(3)The applied study of regional agricultural drought risk assessment at each city inthe Huaibei Plain of Anhui Province is made. The results show that: in2007, thedisturation pattern of agricultural drought risk in the Huaibei plain presents apparentnorth-south difference, with the risk of northern part is higher than that in the south.The risk level of4northern cities represented as Huaibei is higher than that of2southern cities represented as Huainan. The application results show that: the proposedmethodology of regional agricultural drought risk assessment has many advantagessuch as solid theoretical basis, comprehensive assessment contents, wide applicationrange, strong operational and so on, which can totally present the information ofdrought probability and agricultural loss suffered from different magnitude drought ofdifferent regions and is conducive to quantitativly asses the indeterminacy anddynamic process of agricultural drought risk in a changing environment.