【摘 要】
：
近年来,江河源区存在草场严重退化、土地荒漠化过程加剧、水土流失加重以及湿地生态衰退等以草地生态系统为主的生态环境退化问题.分析研究结果表明,在青藏高原特殊的地理气
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近年来,江河源区存在草场严重退化、土地荒漠化过程加剧、水土流失加重以及湿地生态衰退等以草地生态系统为主的生态环境退化问题.分析研究结果表明,在青藏高原特殊的地理气候背景下,经过长期自然演化形成的江河源区脆弱的草地生态系统,对外界环境条件反应极其敏感,季节性过牧等人类活动是造成该区近期草地迅速退化的突破口和主导因素,从而促使气候、鼠害等自然因子作用加剧.江河源区的草地退化,是人为因素和自然因素共同作用下人为加速加剧的结果.
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