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若尔盖草原是中国高寒湿润地区发生大面积沙漠化的典型案例,其沙漠化的成因及发展趋势一直受到极大关注。通过野外考察、遥感卫星影像解译等,着重探讨了鼠害在若尔盖草原沙漠化的形成和发展过程中的作用。结果表明:旱獭洞的分布与丘陵沙丘在坡度和坡向上有高度的相似性。地表致密草皮层发生机械性破坏,致使下伏松散沙暴露是若尔盖草原沙漠化的关键一步。旱獭洞的坍塌在草皮层的破坏过程中起到了至关重要的作用。草皮层破坏后,下伏松散沙被侵蚀,引起草皮层坍塌,导致古沙丘活化,形成流动沙丘。在此过程中,自然因素如风、降水、冻融、重力,人为因素如过牧、牲畜活动,都起到了不同的作用。小型鼠类如高原鼢鼠、高原鼠兔的严重鼠害区可以形成轻度沙漠化。
The Ruoergai grassland is a typical case of large-scale desertification in humid and alpine regions of China. The causes and development trends of desertification have drawn great attention. Through field investigation and interpretation of remote sensing satellite images, the role of rodent pests in the formation and development of desertification in the Ruoergai steppe has been discussed. The results show that the distribution of marmot holes is highly similar to that of hills and dunes in slope and aspect. Mechanical damage to the soil surface of the dense turf layer caused the next loose sand exposure to be a crucial step toward desertification in the Ruoergai steppe. The collapse of the Marmota hole played a crucial role in the destruction of the turf. After the destruction of the turf, the underlying loose sand is eroded, causing the turf to collapse, causing the ancient sand dunes to activate and form a mobile sand dune. In the process, natural factors such as wind, precipitation, freezing and thawing, gravity, human factors such as overgrazing and livestock activities all play different roles. Small mice such as plateau zokor, plateau pika severe rodent area can form mild desertification.