The Study Of Climate Change And Its Impacts On Winter Wheat Yield In Huaibei City

Under the background of global warming, study on the characteristics of climate change and extreme weather events change in certain area, analyze the impact of climate change on winter wheat production, can provide a theoretical reference for the local climate prediction, disaster prevention and mitigation and winter wheat production. In this paper, use daily meteorological data and winter wheat yield data, using trend analysis, wavelet transform and mutation analysis to study the variation of climate change and extreme weather events, analyzes the impact of climate change on the production of winter wheat,the main conclusions are as follows:(1) The annual average temperature, maximum temperature, minimum temperature, spring, autumn and winter temperatures showed a significant increasing trend, winter temperatures had the largest increase (0.51℃/10a), summer temperatures has a weak downward trend; the annual average temperature is the lowest in 70s, highest in the first 10 years of the 21st century; changes in the frequency is high of temperatures; significant quasi-periodic oscillations 4-6a exist in annual and seasonal temperature; a low to high mutation occurs around 1993 of the annual average temperature.Annual precipitation, spring, autumn and winter precipitation tended to decrease, decreasing trend is remarkable in autumn rainfall, summer precipitation shows a slight increase trend, decreasing trend is significantly of the number of precipitation days; the annual precipitation is at leas in the 80s and at most in 60s; in addition to the winter precipitation exists a significant periods of quasi-12a scale, precipitation exist quasi 3-6a-scale oscillations; low to high mutation occurs around 1966 of the annual rainfall.Annual sunshine hours, summer and winter sunshine hours tended to decrease, decreasing trend in summer sunshine hours is significant, sunshine hours in spring and autumn showed a slight increasing trend; the sunshine hours is at leas in the 80s and at most in 60s; in addition to the spring sunshine hours exists a significant periods of quasi-3-5a scale, sunshine hours exist quasi 16-24a-scale oscillations; point mutation was not detected in annual sunshine hours.High temperature days and extreme temperature showed a decreasing trend, decreasing trend is significantly of high temperature days and cold days, increasing trend is significantly of extreme low temperatures; storm and days of heavy rain showed a slight reduction trends, a slight increase trends is showed in storm intensity.(2)The average temperature, the maximum temperature, minimum temperature of winter wheat showed a significant upward trend, where the minimum temperature rise the most significant trends and a low to high mutation occurs around 1989 of the annual average temperature in winter wheat. The temperature factors (average temperature, average maximum temperature, mean minimum temperature) of the growth stage 7 in winter wheat show the same trend, reviving-jointing stage has the most significant warming rate, the average maximum temperature showed a decreasing trend of grouting-maturity, the average minimum temperature showed a significant increasing trendy 0℃ accumulated temperature in growth period and before winter period of winter wheat show a significant increasing trend (p<0.05), the heat resource increased in growth period of winter wheat. Precipitation and sunshine hours tended to decrease, fluctuations is greater in climate yield.(3) The actual yield of winter wheat change significantly increased in 1962-2010. After warming, the fluctuations of climate yield in winter wheat instability increases, average temperature of seeding-tillering stage and sunshine hours of filling-maturity stage are the most significant factor; flood disaster increased frequency in the growth period,heavy floods and big flood disasters are the major disaster to lead a large fluctuations in winter wheat production; the frequency of droughts is reduce, but the extent of drought disasters strengthened; the probability appeared greater in the increased year of climate production,local climatic conditions are more suitable for the production of winter wheat.