淮河流域降水变化对主要农作物气候生产潜力的限制

Influence of precipitation change on climatic potential productivity of major crops in the Huaihe River Basin

针对淮河流域粮食主产区旱涝灾害频繁,严重制约粮食作物生产能力的问题,本文基于淮河流域171站1971-2010年的气象资料及121站作物历年生育期资料,采用气候生产潜力逐级订正模型计算了冬小麦、夏玉米和一季稻的气候生产潜力,着重分析了气候变暖背景下降水变化对作物气候生产潜力的影响。结果表明:近40年淮河流域三种主要农作物的气候生产潜力以一季稻最高,其次是夏玉米,冬小麦最低;各作物气候生产潜力的年际间变异系数均超过10%,其中冬小麦超过20%,但三种作物均无显著的时间变化趋势。各作物气候生产潜力占光温生产潜力的比例(简称气候比)以冬小麦最低,多年平均值仅为49.7%,且变异系数达到25.4%;夏玉米和一季稻的多年平均值分别为67.3%和66.4%,变异系数仅为12.9%和16.3%。降水变化对三种作物气候生产潜力的限制以冬小麦最大,其次是夏玉米,一季稻最小。冬小麦生育期间降水量严重不足,且降水变异系数大,构成了对气候生产潜力的双重限制作用;夏玉米生长季内降水量的偏多偏少和变异系数均是限制夏玉米的气候生产潜力的主要因素;一季稻的气候比则仅与生长季降水量相关显著,气候生产潜力主要受降水量多少的影响。

Frequent droughts and floods in the Huaihe River basin have severely restricted crops production capabilities. To evaluate the influence of climate change on crop productivity, the climatic potential productivity （CPP）of wheat, maize and single-season rice were calculated using weather data from 171 stations and crop growth period data from 121 stations from 1971 to 2010 and stepwise correction modeling. The influence of precipitation changes on crop CPP under the background of climate warming was emphatically analyzed. In the last 40 years, in the Huaihe River basin the single-season rice CPP was the maximum, then maize; wheat was the minimum. The inter-annual variation coefficient of each crop＇s CPP was more than 10%, among which wheat CPP was more than 20%. However, each did not have an obvious change over time. The ratio of CPP to light and temperature potential productivity （abbreviation：climate ratio）of three crops was also analyzed. Multiyear mean climate ratio of wheat was the lowest, only 49.7%, and the variation coefficient was 25.4%, while that of maize and rice were 67.3% and 66.4% respectively, and the variation coefficients were 12.9% and 16.3%. The influence of precipitation change on wheat CPP is most serious, then maize CPP and that of rice CPP is the lowest. Serious shortages in precipitation during the wheat growing season and high precipitation variation coefficient both restricted wheat CPP. The main reasons limiting maize CPP were more precipitation, fewer precipitation and precipitation variation during the growing season. The climate ratio of single- season rice was only significantly correlated to precipitation during the growing season, thus rice CPP was mainly influenced by the amount of precipitation.