四川冬小麦产量对气候变化的敏感性和脆弱性研究

论文以四川冬小麦种植区1981—2012年88个县的气象观测数据和冬小麦生产数据为基础,采用一元线性回归和逐步回归等方法,评价四川冬小麦产量对单个气候因子及气候变化的敏感性与脆弱性。结果显示：假设冬小麦生育期内平均气温和日较差升高1 ℃、降水量下降100 mm、辐射量下降100 MJ/m²,冬小麦的产量随之发生变化,全生育期降水量下降导致产量敏感的面积最大,占整个研究区域播种总面积的6.5%;而辐射量下降使产量脆弱的面积最大,为2.4%。从各个生育阶段来看,研究区域内冬小麦产量对播种到拔节期辐射量下降表现为敏感和脆弱的面积比例最大,分别占9.4%和7.9%。受到4种气候因子变化的综合影响,产量对冬小麦生育期内气候变化表现为敏感的面积占播种总面积的40.0%,在7个冬麦区均有分布,产量变化为-23.0%~9.5%;产量脆弱的面积占14.0%,主要分布在川西北高原大部及盆西、盆南和川西南的部分区域。

Study on the Sensitivity and Vulnerability of Winter Wheat Yield to Climate Change in Sichuan Province

Based on the meteorological observation and winter wheat production data during 1981-2012 from 88 counties well spreading over the winter wheat growing regions of Sichuan Province, the sensitivity and vulnerability of winter wheat production to climatic factors and climate change were estimated by using the regression method. The results showed that the air temperature and diurnal temperature range increased in the entire growth period of winter wheat during 1981-2012, but the precipitation and solar radiation showed decreasing trends in some counties while showed increasing trends in others. With a 1 ℃ increase of air temperature in growing-season, 1 ℃ increase of diurnal temperature range, 100 mm decrease of precipitation and a 100 MJ·m^-2 decrease of radiation, the yield of winter wheat in some of these regions was sensitive to the changes. From sowing to maturity, the area of winter wheat that was sensitive to decreasing precipitation is the largest, which took 6.5% of the total sown area. As for vulnerability, the area vulnerable to decreasing radiation was the largest, which was 2.4%. As for different growth stages of winter wheat, the area of winter wheat that were sensitive and vulnerable to the decrease of radiation during sowing to jointing period were the largest, which were 9.4% and 7.9% respectively. Taking the four climatic variables together into consideration, the area of winter wheat that had significant change in yield was roughly 40.0%, and the yield changed -23.0%-9.5%, but the area showed vulnerability took about 14.0%. The region with yield vulnerability mainly located in the northwest plateau of Sichuan, and part of western basin, southern basin and southwest Sichuan.