Natural Disaster Risk Assessment of Grain Production in Dongting Lake Area, China

Dongting Lake area is one of the primary commodity grain bases in China, while the grain production there is suffering from serious harm of natural disaster such as flood, drought, pests and mouse damage. In general, the historical data recorded of natural disasters in small region are not enough to be used for estimating the probability distribution in risk assessment, because the size of the sample observed is smal1. In this study, the method “Information Diffusion” is used to change limited sample observations into fuzzy sets, and a quantitative analyzing model for natural disasters risk assessment is proposed. Based on the statistical data of grain planting area and hazard area during the period of 1986-2006 in Dongting Lake area, the probability of natural disaster risk of grain production was calculated by using the Information Diffusion Theory in each county. The results showed that the probabilities of natural disaster risk of the area hazard ratio (AHR) of grain production over 10% , 20%, 30%, 40% were between 0.3576∼0.9344, 0.0880∼0.8618, 0.0080∼0.7757, 0∼0.6569 respectively in different county. Meanwhile, the natural disaster risk assessment maps of grain production were obtained based on GIS. The spatial distribution characteristics of natural disasters risk of grain production were analyzed. Finally, the strategies and measures were put forward to reduce natural disaster risk of grain production in Dongting Lake area.