半干旱黄土丘陵区不同整地方式下退化草地植物群落恢复特征

Vegetation Restoration with Different Land Preparation Methods in Degraded Grassland in Semi-arid Loess Hilly Region

[目的]对比分析2种造林整地措施处理后的草地植物群落特征,为宁南半干旱黄土丘陵区植被恢复和建设提供理论依据。[方法]以固定样地与群落样方调查数据为基础,对比了"88542"水平沟、鱼鳞坑2种不同整地方式下群落动态特征。[结果](1)在一定的时间尺度上,生境的异质性对鱼鳞坑整地植物群落的结构影响较大,整地方式对植物群落结构特征的影响不明显。(2)生境条件的不同影响了群落的多样性。鱼鳞坑整地的植物群落由于生境的异质性较大,促成了较高的多样性。植物群落物种多样性由高到低的顺序为:鱼鳞坑整地>"88542"水平沟整地>天然封育草地。(3)植物群落多样性总体表现出随着年限的延伸,整个示范区的植物群落物种的多样性开始下降。[结论]不同人为干扰方式和不同生境对植物群落多样性有明显影响。

[Objective] The effect of two site preparation methods was analyzed on plant community characteristics of grassland in order to provide scientific basis for vegetation restoration and construction in the semiarid loess hilly region of Southern Ningxia region.[Methods] By investigating the fixed sample plots and communities data, we compared the community dynamic characteristics effected by site preparation methods of ＂88542＂ level trench and fish-scale pits.[Results] （1） In temporal scale, the heterogeneity of habitat greatly affected the plant community structures in fish-scale pit site preparing mode. Site preparing mode had a little effect on the characteristics of plant community structure. （2） The difference of habitat environmental affected species diversity. Fish-scale pit site preparing mode led to higher heterogeneity of habitat environment, thus improving diversity. The order of species diversity among three sampling plots was fish-scale pit site preparing 〉 ＂88542＂ level furrow site preparing 〉 natural closed steppe. （3） The community diversity of the demonstration area was declining with time.[Conclusion] Different artificial disturbance and different habitat environment had important effect on plant diversity.