摘要
研究草原生态系统的蒸降差变化,对探讨气候变化条件下的水分循环和草原生产力等具有重要意义。本文利用1960-2004年内蒙古典型草原区及其周边38个气象台站的气候资料,采用Penman-Monteith公式计算暖季(4-8月)的潜在蒸散量及相应的蒸降差,用经验正交函数(EOF)和旋转正交函数(REOF)研究蒸降差的时空分异特征。结果表明:内蒙古典型草原区暖季蒸降差的主要空间异常型表现为全区一致偏高或偏低,这是典型草原区主要的空间型;暖季蒸降差空间分异大致可划分为4个异常区即北部区、东北部、中部和西部区;随时间的推移暖季蒸降差有降低的趋势,且具有明显的阶段性变化特征。
The variations of differences between the evapotranspiration and precipitation in the grassland ecosystem were studied to reveal the water circulation and the productivity in the grassland under the climate change conditions. Based on the climate data of 38 stations throughout the Inner Mongolian steppe during 1960 to 2004, the spatial and temporal variations of differences between the evapotranspiration and the precipitation during April to August were studied, by using Penman - Monteith formula. The results showed that the main spatial anomaly feature of the differences between the evapotranspiration and the precipitation during warm season was coincidently high or low. The steppe could be divided into four anomaly regions in accordance with differences between the evapotranspiration and the precipitation. With times lapse, the differences between the evapotranspiration and the precipitation showed a declining tendency during past 45 years.
出处
《中国农业气象》
CSCD
2008年第3期264-267,共4页
Chinese Journal of Agrometeorology
基金
国家社会公益研究专项(2004DIB4J170)“内蒙古草原干旱监测预测研究”
关键词
典型草原
潜在蒸散
蒸降差
时空分异
Steppe
Evapotranspiration
Spatial and temporal variation
Difference between evapotranspiration and precipitation
