内蒙古草地退化对区域气候影响研究进展

地表覆被变化能改变地表能量平衡和水文循环,土地利用/覆盖变化的气候和环境效应已受到广泛关注。笔者对20年来内蒙草地退化对区域气候影响研究方面的进展进行了分析总结。50年来在人文和自然因子驱动下内蒙草地严重退化,草地产量下降,植被覆盖度减小,沙化面积增加。全球气候模式和区域气候模式荒漠化数值试验结果表明,内蒙草地退化可使该地区夏季降水减小,气温升高,加剧了干旱化。草地退化气候影响机制是植被退化使得植被覆盖度和叶面积指数减少,陆面参数变化引起了水分循环和能量收支的变化并进一步影响大气环流的结构。

Research Progress in Effects of Grassland Degradation on Regional Climate in Inner Mongolia Region

Changes of land cover can alter hydrological cycle and surface energy balance.The effects of changes of land cover on climate and environment have attracted a wide concern.The paper analyzes and summarizes progress in studies on effects of grassland degradation on regional climate in the Inner Mongolian region.Continual drought,rapidly expanding population,increasing human land use and overgrazing have led to grassland degradation in the past 50 years.Numerical studies with globe climate model and regional climate model coupling a land surface model indicated that grassland degradation made drought more serious by reducing summer precipitation and increasing surface air temperature.Mechanisms involved in effects of degradation on climate are that grassland degradation reduces vegetation cover and leaf area index and changes surface parameters,which results in changes in energy balance and water cycle and finally effects air circulation.