石羊河流域1970—2009年气候变化对农业生产结构的影响

Effects of Nearly 40 Years Climate Change of Shiyang River Basin on Agricultural Production Structure

为了提高人们认识气候变暖对农业生产的利弊关系,把握影响粮食生产主要气象因子,适时调整农业种植结构,趋利避害,达到粮食高产稳产的目的,依据石羊河流域5个气象站1970—2009年的资料,将资料分为2个阶段1970—1989年,1990—2009年,然后分别统计年、月、春(3—5月)、夏(6—8月)、秋(9—11月)、冬(11—次年2月)四季平均气温、降水、积温、无霜期日数等相关资料进行前后对比分析,结果表明,1990—2009年较1970—1989年,年平均气温升高了1.0℃,升温春季>冬季>夏秋季;年降水增加了5.7 mm,在月季分布上6月减少了7.1 mm,7月增加了4.4 mm,且时空分布不均;同时农耕期的有效积温明显增多,无霜期日数增加,使农业种植结构发生了变化,玉米、葡萄、棉花等喜温作物种植面积进一步扩大,春小麦、春油菜等喜凉作物种植面积逐年减少,小麦收获后剩余积温增加,热量对套种、复种品种的限制作用大幅降低,使当地农业生产由过去一年一熟朝着一年两熟的趋势发展。

In order to improve people to understand on the favorable and unfavourable relationships between climate warming and agricultural production,grasp main meteorological factors on food production,timely adjust agricultural planting structure,draw on advantages and avoid disadvantages,and to hit the target of high and stable grain output,the meteorological information of five meteorology stations in Shiyang River Basin in Gansu from 1970 to 2009 were involved and analyzed.The related meteorological data were divided into 2 stages,i.e.,1970-1989 for the 1st stage,and 1990-2009 for the 2nd stage.Average temperature,precipitation,accumulated temperature,frost-free period and other relevant data in year,month,spring（March to May）,summer（June to August）,autumn（September to November） and winter（November to February） were subjected to statistical analysis,and compared between the 1st and the 2nd 20 years.The average temperature was increased by 1.0℃ in the 2nd 20 years,as compared to the 1st 20 years.The temperature increase scope was ranked as spring wintersummer and autumn.The average precipitation was increased by 5.7 mm in the 2nd 20 years.The precipitation was decreased by 7.1 mm in June and increased by 4.4 mm in July averagely.The space-time location of the precipitation was not well balanced.In addition,there was a significant increase in the effective accumulated temperature and the frost-free period in the 2nd 20 years,agricultural planting