近20年气候变暖对黑龙江省水稻增产的贡献

Contribution of Climate Warming to Rice Yield in Heilongjiang Province

研究过去的气候变暖对作物产量的影响是认识变暖对农业影响的有效途径,但如何定量区分出气候变化和技术发展对粮食作物的影响程度是目前研究的难点.本文提出的算法在一定程度上可以克服传统算法缺陷,用此方法估算过去20年气候变暖对黑龙江省水稻单产增加的贡献率,结果表明:20世纪80年代相对于70年代水稻单产增加了30.6%,其中由气候变暖带来的增产量占实际增产量的12.8%～16.1%,相当于使70年代的单产增加3.9%～4.9%.20世纪90年代水稻单产较80年代增产42.7%,其中,气候变暖对单产增加的贡献率约为23.2%～28.8%,相当于在20世纪80年代的单产水平上增产9.9%～12.3%.

Studying impact of the happened climate warming to the crop yield is an effective approach for understanding the impacts of climate change on agriculture. In this paper, a new method is put forward to calculate climate yield with a climate trend, which may overcome the disadvantage of traditional method. In the new method, a referenced period that satisfies the hypothesis of traditional method is selected to construct a function on the main meteorological factor and climate influence coefficient by regression. This function can be used to calculate climate influence coefficient of other years. Rice yield in Heilongjiang province is mainly restricted by temperature. A case study on contribution of climate change to rice yield change from 1952 to 2000 is made in this region. The result shows that, although non-climatic forces have likely dominated the trends in per unit area rice yield in Heilongjiang province, the impact of climate warming on rice becomes more and more prominent during the past 20 years. The real rice yield per unit area in the 1980s is 30.6% higher than that in the 1970s. The increased yield due to climate warming is 12.8%-16.1% of the real increased yield. The real rice yield per unit area in the 1990s is 42.7% higher than that in the 1980s. The increased yield due to climate warming is 23.2%-28.8% of the real increased yield.