1981年至2010年中国东北地区春玉米气候潜力时空变化分析

Temporal-spatial Variation of Spring Maize Climatic Productivity from 1981 to 2010 in Northeastern China

在1981年-2010年中国东北地区108个农业气象站逐年气象数据基础上,本文通过运用AEZ模型模拟其春玉米光温潜力、气候潜力变化过程,分析了其春玉米气候潜力年际变化特征和变化趋势。研究中以1年为单位的模拟实验减少了玉米气候潜力变化分析的不确定性,而全区尺度的模拟从宏观角度揭示了玉米气候潜力变化空间格局。结果表明:东北地区春玉米气候潜力年际变化大,标准差为3.05t/hm2,大兴安岭南部和东北平原西部为全区高值区。气候潜力年际变化大的主要影响因子是水分条件,其次是光照和热量。近30年东北地区春玉米气候潜力明显减少且减少趋势空间差异明显,呼伦贝尔高原-大兴安岭南部-吉林西部一带减少最快。气候潜力主要因降水量减少而下降,升温的作用较小。该研究结果可为东北地区玉米种植宏观决策提供支持。

Maize is a major food crop in China,widely used to feed livestock,and an important industrial resource;however,climate change is a significant threat to food security in China.China is currently the number two producer of maize and has the second largest plantation area in the world;northeastern China is a main maize cropping zones in China.Recent research has revealed that maize production is expected to be affected by climate change but little research has focused on the spatial pattern and annual fluctuation of maize climatic productivity in this region.Because of the existing monsoon climate,information on temporal and spatial variation in maize climatic productivity in northeastern China is crucial for maize production decision-making.Based on an AEZ model and using climatic data from 108 observation stations across northeastern China from 1981-2010,we estimated annual photosynthesis-temperature productivity and climatic productivity of spring maize.Annual variation and trends in spring maize climatic productivity were then analyzed using GIS technology.By modeling productivity per year the experiment reduced merge error,took a regional perspective,and allowed us to analyze maize climatic productivity at two levels（photosynthesis-temperature productivity and climatic productivity）.We found that average annual variation in spring maize climatic productivity was 3.05t/ha and this varied spatially.Average annual variation in spring maize climatic productivity in the south of the Daxing＇an Mountain range and west of the Northeast China Plain was higher than for other areas.Water supply is the main factor constraining average annual variation,followed by sunshine and heat conditions.In the last 30 years,spring maize climatic productivity has obviously decreased and the average decreasing trend for the whole region was a 0.7t/hm2 decrease per 10 years.This rate of decline in spring maize climatic productivity varied spatially and was higher for the Hulunbeier Plateau,south of the Daxing＇an Mountains and west of Jinlin province.The decrease in spring maize climatic productivity in northeastern China was mainly caused by reduced precipitation,and to a lesser extent warming temperatures.Our analysis will provide scientific information for governments to expand spring maize production in northeastern China and provide a foundation for climate change research in the region.