天水地区粮食生产对气候变化的响应

收集1978～2010年天水市7个县(区)农业生产资料和气象站逐日气温、降水资料,应用柯布-道格拉斯生产函数方法将粮食产量分解为气候产量和经济产量,然后用数理统计方法分析了粮食产量、气候影响程度指数、≥10℃积温、生长季降水的年际变化特征及其关系。结果表明,33年间天水粮食产量呈稳步增加趋势;气候变化为温度上升、降水减少趋势,≥10℃积温、降水大约在1993年出现明显上升和下降转折点;气候变暖对粮食生产有利,降水减少对粮食生产不利;33年间气候影响程度总体趋势增大,且年际差异明显,1993年之前积温、降水对产量的影响程度为正贡献,1994～2000年积温增多、降水减少对粮食产量为负贡献,2000年之后为正贡献。≥10℃积温、生长季降水对粮食产量的影响以积温更为敏感。

Impact of Climate Change on Crop Yields in TianShui

Collecting agriculture production data,precipitation data and everyday air temperature during 1978-2010 in 7 area in Tianshui City,resolved grain yield into climate yield and economic yield by using Cobb-Douglas production function,the interannual variation of grain yield,climatic index,accumulated temperature of ≥ 10 ℃ and precipitation in grow up age were analyzed by mathematical statistics method.The results showed that: In 33 years,the grain yield have a trend of steady rise;The climatic variation have a trend of rise in temperature and reduce in precipitation,the accumulated temperature of ≥ 10 ℃ and the precipitation have a very clear rise and reduce turning point in 1993;Climatic warming is beneficial to agriculture production,precipitation reducing is harmful to agriculture production;In 33 years climatic impact have a rise trend in total and have a clear interannual difference,the accumulated temperature and precipitation have a positive effect to grain yield before 1993,the accumulated temperature rising and precipitation reducing have a negative effect to grain yield from 1994 to 2000,after 2000 they have a positive effect to grain yield.The accumulated temperature of ≥ 10 ℃ and precipitation in grow up age both influence the grain yield but the accumulated temperature is more sensitive.