若羌县近50a来气候变暖及其对农业生产影响分析

利用若羌县气象站1958～2007年日平均气温实测资料,深入分析若羌县气候变暖及其对农业生产影响。分析结果显示:(1)近50a来若羌县年均气温呈增加趋势,其线性倾向率为0.204℃/10a,50a增温达1.02℃,年均气温波动基本与我国西北地区气温变化趋势一致。(2)年内气温的季节变化差异明显,各季节气温均呈上升趋势,其中,冬夏两季对全年气温上升贡献较大。(3)近50a来≥0℃、≥10℃、≥20℃活动积温值增加,持续天数增多,而<0℃负积温绝对值明显减少。(4)近50a来若羌县气候显著变暖,热量资源增加,使喜温作物面积扩大,生长期延长,对越冬作物有利;同时病虫害越冬存活率上升,防止难度加大,气候变暖对若羌县农业影响是利弊并存。

Influence of climatic warming on agriculture production for recent 50 years in Ruoqiang county,Xinjiang

Accumulated daily mean temperature,the highest temperature,the lowest temperature were analyzed to illustrated the response of thermal resource to climate warming and the impact of climate warming on agricultural production based on the meteorological data during 1958-2007 in Ruoqiang District,Xinjiang by methods of regression analysis and trend line analysis.The results indicate that :(1) In recent 50years mean annual temperature in this district was in an increase trend,and the increasing rate was 0.19℃/10a.The annual average temperature(11.81℃)fluctuated around the average value and was same trend with the temperature in northwestern China.Seasonal variability of air temperature was obvious.(2)Seasonal temperature showed ascendant trend,in which the contribution of temperature increase in spring and summer to annual temperature increase was high.(3) The daily accumulated mean temperatures of collected ≥0℃ and ≥10℃ increased.The absolute value of negative accumulated temperature <0℃ reduced obviously.(4) As the trends of climate appeared warming since the 1980s in Ruoqiang county of Xinjiang,the heat resource increased,so it was benefits for the winter crops,extending of thermophilic crops' areas.At the same time,it increased winter pest egg(cocoon) survival rate.Consequently,there are both advantages and disadvantages of climate warming to the agriculture in Ruoqiang county.