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出 处:《西南农业学报》2009年第6期1662-1664,共3页Southwest China Journal of Agricultural Sciences
摘 要:经近40年连续遥感监测发现,四川省若尔盖高原草地沙化与湿地退化现象十分严重。2004与1966年相比,草地沙化面积增加52 898.4 hm2,增幅达586.7%,2005与1986年相比,沼泽湿地减少115 051.0 hm2,减幅达54.2%。这两种事实表明,该地区土地荒漠化正在加剧。究其原因有:排干沼泽和牲畜超载等人为因素是主要原因,气候干暖趋势加剧了这一变化。若尔盖高原处于"长江上游生态屏障"的重要部位,其土地荒漠化严重趋势应引起各方高度重视。The desertifieation of grassland and degradation of wetland in Ruoergai plateau in the northwest of Sichuan Province were very serious by continuous 40 years remote sensing monitoring. The area of grassland desertification in 2004 was more 52898.4 hm2 than that in 1966 and had an increase amplitude of 586.7 %. The area of marsh wetland in 2005 was less 115051.0 hm2 than that in 1986 and had a reduction amplitude of 54.2%. The results showed that the desertifieation in Ruoergai plateau was aggravating. The reasons were human factors ,including livestock overloading and etc. ,and climate warming also accelerated the desertifieafion in Ruoergai plateau
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