Climate Risk Evaluation For Single Cropping Rice In Huaihe Watershed On Niche Fitness

With the development of the global climatic change research, the climatic risk study on natural ecosystems and socio-economic systems become the main areas of the climatic change gradually. Research on the spatial differences of crop response to climatic change has great significance to adapt climatic change actively, to draw measurements and countermeasurements and to ensure sustainable development of agriculture.In order to analyze the change of rice climatic suitability and risk in Huaihe Watershed quantitatively, the article selected 50 weather stations, using their precipitation, average temperature and average sunshine per ten days from 1960 to 2005, and chosing the model of rice climatic suitability and risk. Through analysis the author gets the following results.(1) Huaihe Watershed is classified three types: the most suitability region, more suitability region and suitability region through analyzing the spatial differences in rice temperature suitability, precipitation suitability and sunshine suitability in Huaihe Watershed. The result also shows that the rice sunshine suitability and climatic suitability are decreasing by 0.035/10a and 0.01/10a, temperature suitability keeps on current level, precipitation suitability is increasing by 0.001/10a.(2) Based on the suitability change of per station, the rice climatic suitability change in Huaihe Watershed is classified three types: faint decrease, decrease and strong decrease. The decreases of tassel and florescence suitability have great effect on faint decrease region, the decrease of grouting and autumn stage climatic suitability is fastest in all stages in decrease type. And tassel and florescence suitability decrease obviously in strong decrease region.(3) The article analyzed the risk probability distribution of rice output decrease to 10%, 20%, 30%; the result shows that every risk probability distribution of rice output decrease has regionalization and continuity obviously,and the risk probability in the west is higher than in the east.(4) Under the sistuation that the air temperature rise,the temperature suitability of rice in Huaihe Watershed these are calculated , the temperature suitability is increase ,and the increase range in the north is higher than in the south,the article analyzed the growth rate showed a certain regular of latitude distribution from south to north.(5)Based on probability intensity of precipitation, temperature, sunshine and climatic risk in Huaihe Watershed, the precipitation, temperature, sunshine and climatic risks are divided three regional types: low risk region, risk region and high risk region. Through analysis the article can get the following results: the lower suitability in Whole growth period, the greater inter-annual fluctuation, the higher risk of rice normal growing and foison. The change trend of rice risk has the temporal and spatial differences in the basin obviously. The climatic risk in Huaihe Watershed takes on increasing trend in recent decades. In spatial change trend, the climatic risk of the eastern coastal region increases and it is possible to move to inland, and the western regional climatic risk also increases and it is possible to move to the eastern coastal region.