陕北黄土区不同地形自然恢复的植物多样性  

Plant diversity with natural recovery on different topographies in north Shaanxi loess area

作　　者：陈文思[1] 朱清科[1] 卢纪元 李镇[1] 艾宁[1] 于长城 

机构地区：[1]北京林业大学水土保持学院水土保持与荒漠化防治教育部重点实验室,北京100083 [2]内蒙古巴彦淖尔市乌拉特前旗园林局,内蒙古巴彦淖尔014400

出　　处：《中国水土保持科学》2016年第2期103-110,共8页Science of Soil and Water Conservation

基　　金：林业公益性行业科研专项经费课题"黄土丘陵严重侵蚀区植被恢复和重建技术研究"(201104002-2)

摘　　要：以陕北吴旗县自然恢复15年的合沟流域为例,探究植被在自然恢复过程中的群落结构和植物多样性特征,为半干旱黄土区人工林草植被构建提供科学依据。实验采用样方法,从地貌部位、坡向及坡度3个方面对研究区植物群落结构和植物多样性进行调查分析。结果表明:1)合沟流域自然恢复15年后仍以草本群落为主,地带性植被类型是铁杆蒿+长芒草群落;2)先锋乔木和灌木已经出现在沟底和切沟、塌陷地、缓台等土壤水分条件较好的坡面微地形中;3)植物多样性在地貌部位上从大到小的顺序依次是梁峁坡、梁峁顶、沟坡和沟底,随坡向的大小顺序是阴坡>半阳坡>半阴坡>阳坡,随坡度的增大呈现先减小后增大再减小的"S"形变化,在32°处取得最大值。建议在人工植被建设的过程中,沟底和水分条件好的坡面微地形可以适当配置乔木和灌木,而阳坡陡坡以保护和恢复草本植物为主。[ Background] The characteristic of the plant community structure and the plant diversity in the course of natural restoration of vegetation is a scientific basis to construct artificial vegetation in semi- arid loess area of northern Shaanxi, which is the typical fragile ecological region. [ Methodsl The paper explored what was the influence mechanism of the topography on natural vegetation in this region, for Hegou watershed in Wuqi County of Shaanxi Province as an example. Based on the vegetation survey in 50 sampling plots, the community structure and the plant diversity were analyzed from three aspects of landform, slope and gradient. [ Results] The results showed that the plant community was still mainly herbaceous and the zonal vegetation type was Artemisia sacrorum ＋ Stipa bungeana communities in this watershed, which had been fenced for 15 years. Not only were there Populus simonii and Salix matsudana on gully bottom, but there were also three trees of P. simonii, Ulmus pumila and Ameniaca sibirica and six shrubs of Buddleja alternifolia, Prinsepia utilis, Spiraea trilobata, Caragana korshinskii, Caragana microphylla and Periploca sepium on some micro-topographies of slope aspect with favorable water condition, i. e. , gully, collapse and platform. On different landforms, the order of the richness index was valley slope 〉 gully slope 〉 top valley 〉 gully bottom; that of the diversity index was valley slope 〉 top valley 〉 gully slope 〉 gully bottom; and that of the evenness index diminished from top to bottom. On different slopes, both the diversity and evenness indices were in the same order of size, i. e. , shady slope 〉 semi-sunny slope 〉 semi-shady slope 〉 sunny slope, but the richness index was in the order of semi-shady slope 〉 semi-sunny slope 〉 shady slope 〉 sunny slope. Moreover, with the increase of gradient, the richness index decreased gradually, and the evenness and diversity indices were both of ＂ S＂ types, and its maximum value was at 32~ of gradient. [ Conclus

关 键 词：地貌部位 坡向 坡度 植物多样性 半干旱区 

分 类 号：Q948[生物学—植物学]