Contribution of Climate Warming to Rice Yield in Heilongjiang Province
近20年气候变暖对黑龙江省水稻增产的贡献

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.