| It has become an indisputable fact that climate warming is the main features ofthe global climate change. Under the background of the global climate warming,regional climate has significantly changed. Agriculture production is most closelysector with climatic resource, the growth, development and level of production ofcrop are heavily influenced by meteorological factors such as light, heat, water, powerand control.Hedong region of Gansu is located in the eastern monsoon area, in the NorthwestArid area of China and the Qinghai-Tibet cold plateau either, the agriculture there issemi-arid and sub-humid rain-fed agriculture. Hedong region is not only the sensitivearea of climate change, but also the ecological environment vulnerable area.The use of accurate meteorological date, we made a profound analysis on thevariation characteristics and the impact on Agricultural production of agriculturalclimate resources in the study area, thus, the appropriate use of agricultural climateresources and effective measures will have important significance to promote thesustained and stable development of agriculture in the region.Based on the observed data which provided by13stations of the StateMeteorological Administration and31sequence longer local sites in Hedong region ofGansu from1961-2010. The research methods such as climate tendency rate method,Inverse distance interpolation space, FAO Penman-Monteith formula method andtrend surface simulation and spatial interpolation are used in analyzing temporalvariation characteristics of climate resources in the study area. On this basis, farmingand animal husbandry observation dates are combined to analyse crop growth anddevelopment, planting structure, production, the growth of the animal husbandry andthe response to the climate change, we get the following conclusions:（1）Under the background of the global warming, the temperature of GansuHedong region has a obvious rising trend, the annual average temperature tendencyrate is0.26°C/10, it has passed the significance level test of0.05. Temperaturechanges in overall showed an increasing trend on the spatial distribution, among that,the north-central plateau of Longdong and in the northern part of the region inLongzhong plateau is the most obvious. As for the season, different space interannual difference is presented in each season temperature, but the seasonal and annualtemperatures are both on the rise, and temperatures in winter showed the mostsignificant rise.The average annual temperature is exist13a transformation periodand1993a mutations from low to high.≥0℃and≥10℃accumulated temperaturewere significantly increased, and＜0℃negative accumulated temperature showed atrend of decrease. The stability through the first day of0℃、10℃earlier, the last daycame later, the day numbers of duration showed an increasing trend.（2）The average annual rainfall has a downward trend in nearly50years, and bythe speed of14.16mm on average every10a, there is a transform of positive tonegative, and it has a periodic transformation of19a,the mutation is not obvious. Onthe spatial distribution, precipitation in most of the area showed a decreasing trend,and the decrease in the southeastern region is higher than the northwest. As for theseason, Except that the winter precipitation was slightly increased, precipitation inother season showed a trend of decrease, and the tendency is the most obvious in insummer and autumn. The potential evapotranspiration quantity showed a pattern of“The east is greater than the west, Mountain area is greater than the plateau” on thespatial distribution, in addition, it increases at a rate of about10.63mm/10a, passedthe significance level test of0.01.The annual surface humid index decreases at aspeed of0.02/10a,it showed a significant difference between north and south, and itdecreases from south to north in the spatial distribution. In seasonal distribution, therate of change of humid index in spring, summer, autumn, winter four seasons isrespectively-0.015/10a、-0.019/10a、-0.066/10a、0.08/10a, Except that humid indexrises in winter, it reduces in other seasons, among that, the range of decrease is themost in autumn, and the least in spring.（3）The climate trend rate of sunshine time in the whole region has a tendencyof reduction, the speed is4.69h in per decade. As for the season, spring and autumnsunshine hours showed an increasing trend, the most significant of the increasingtrend in spring, summer, winter downward trend, At the same time, annual sunshinetime there is a cycle of about25a. Annual wind speed also showed a slight decrease,every10years reduced to0.05m/s, is about27a transformation period and in1963a and1963a mutation occurred. In terms of season, except there was a slight increase in the winter, other season showed a trend of decrease.（4）The annual crop climate productive potential has a tendency of reduction inHedong region, the linear trend rate is-1.60g m-2a-1.There is a shift from thepositive to the negative in1986, the main reason is nearly50years Hedong regiontemperatures rise and declining precipitation caused. The production potential of cropseasons showed different degrees of reduction trend, especially in autumn the mostsignificant, followed by the summer. Winter wheat significantly shorten the trend inthe whole stages, each of10a shortened6-7d, seeding time delay, Heading stage tomilking stage extended interval, milking stage to maturity shorten, spring wheatgrowth period shorten, each of10a shortened4-5d, milking stage to maturity intervalshortened. Corn sowing, seedling emergence postponed trend and heading stage,silking stage, mature over time showed a trend advance. The spring wheat areareduced year by year, winter wheat planting area is expanding, corn plantingproportion also rise year by year in Hedong region, mainly due to temperature rise,≥0℃and≥10℃accumulated temperature increase caused. Climate warming,result in great changes of crop planting structure,21st century compared with beforethe90s, the winter wheat planting boundary to the north, the west extension, andexpand to the high altitude. Observation area in winter and spring wheat and maizeproduction tended to decrease, mainly due to the decrease in precipitation in thegrowing season and high temperature both synergy.（5）The region’s major grass advantage forage grass Elymus nutans. Astemperatures rises, the grass flowering period has been moved up10-12d,and20-22din mature period in recent20years. At the early stage of the forage growth anddevelopment of seedling stage, heading stage, yellow withered in the late stage,affected by indignities of moderate rainfall, forage development period is fluctuated.Due to warm and dry climate, drought, grassland degeneration, desertification andPest rampant become a serious problem, which made the feed-animal balancecontinuously compounded. |
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