奈曼旗过牧沙漠化草地在封育条件下植被的演变及其恢复

对内蒙古奈曼旗沙漠化草地封育2年、3年和8年保护地围栏内、外植被调查,通过聚类分析分出9个植物群落类型。研究表明:沙漠化草地封育后植被盖度增加,植物群落类型增多。同时促进了沙漠化草地中沙丘的固定,并使地表起伏趋于平缓。在强烈发展中的沙漠化土地中进行草地封育,生物量至少在8年内呈提高趋势。计算表明,封育效果和封育时间成正比,但以封育2、3年内的植被恢复较快。

SUCCESSION AND RECOVERAGE OF OVERGRAZING PASTURE VEGETATION UNDER ENCLOSURE IN NAIMAN BANNER

In this study the changes in landscape and vegetation between insideand outside the enclosures (had been fenced for 2, 3 and 8 years repec-tively) in the desertified rangelands of Naiman Banner were compared.The comparison shows that the original shifting sandyland within the en-closures become fixed and the association of different plant communitytypes are getting complexed with duration of protection. The biomass andplant coverage in the protected area have been increasing during a protec-ted period of at least 8 years. During the first 3 years of protectionthe restoration of vegetation is more active than during the later time.