| The emergence of drought, the drought continued and the risk level affected by climate, soil, agriculture and natural resource limitations and adaptability of crops, by the local regulation of the available water resources capabilities change, and by the level of socio-economic development constraints. Changes in these factors directly affect the crop suitability, risk of drought and drought in the material, financial, scientific and technological input level. Drought is often seen as emergencies in the past, resulting drought emergency response mode patterns are more focused on post-disaster emergency management and disaster recovery, very little before the occurrence of drought make valid judgments and reaction, and not fundamentally reduce the likelihood of drought and the subsequent potential loss and impact. With the impact of drought on society more and more people realize the inadequacy of drought response area, to promote risk assessment prior to the occurrence of drought are valued, drought risk assessment designed to address the risk of drought likely brought about the probability and the resulting loss.Winter wheat growing period usually in October to June next year, Beijing, Tianjin and Hebei region rainfall is generally concentrated in June-August. Winter precipitation occurs time and time is not uniform water demand phenomenon. Drought direct threat to winter wheat production, have a serious impact on the economy. Beijing-Tianjin-Hebei area of winter wheat yield fluctuations directly affect our food security, scientific assessment of Beijing-Tianjin-Hebei area planted winter wheat drought risk is of great significance for regional drought of winter wheat, reducing the risk of drought, reducing the loss of drought-reduced production, etc. become urgent. Drought risk assessment and zoning of the results can guide the varieties of winter wheat planting area, scientific irrigation and drought prevention science.By GIS Using drought's characteristics for risk assessment, drought index selection and analysis. In accordance with the drought caused by various factors, the degree of re-classification index for the assessment to determine the appropriate weight. Statistical analysis using GIS and spatial overlay analysis functions drought risk assessment, to achieve drought prediction. In winter wheat's nature, natural conditions, socio-economic environment for an evaluation. This paper analysis by AHP weights, using GIS overlay analysis features the Beijing-Tianjin-Hebei area is divided into: high, medium and low risk areas and non-growing areas.Zhangjiakou, Chengde, and Taihang Mountain are winter wheat non-growing areas where the average altitude more than 500 meters. Drought risk score greater than 1.9 the region is a high risk of winter wheat in arid areas, including Beijing, Tianjin, Langfang most parts of the northern Qinhuangdao, Tangshan south, Changzhou and other local areas north. Drought risk score from 1.4 to 1.9 in the region is in drought risk areas, mainly in central and northern Tangshan, Baoding in eastern, central and southern Changzhou, eastern Xingtai, Hengshui and much of the Taihang Mountain. Drought risk score less than 1.4 area is arid, low-risk areas, mainly located in Shijiazhuang, Handan most of the region, Xingtai, Baoding in central and southern areas.In different regions, winter wheat owns nature, natural conditions, socio-economic environment, and the influence of different hazards. For the different regions of drought hazard, to develop regional defense drought is necessary. Drought risk assessment is in accordance with the results, regional location and economic level of agricultural development. The area is divided into non-growing region, Beijing and Tianjin area, Eastern Hebei Plain area, Heilonggang and in the piedmont region of five parts. For the regional conditions, the yield increase of winter wheat and constraints. Proposed defense measures to reduce the risk of drought winter wheat, winter wheat drought risk measures were developed.
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