高级检索

    黄土丘陵沟壑区退耕地自然恢复植被特征及其与土壤环境的关系

    Characteristics of vegetation with natural restoration in removal lands in loess hilly-gully region and the relationship between the characteristics and soil environment

    • 摘要: 为给黄土高原退耕地的植被恢复和重建提供科学依据,以黄土高原丘陵沟壑区的安塞县为例,用系统聚类和逐步多元回归的分析方法,对退耕地自然恢复植被的演替阶段进行划分,并定量分析群落演替过程中的植被特征及其与土壤环境的关系。结果表明:黄土丘陵沟壑区退耕地自然恢复草地的演替,依次经历猪毛蒿群落→赖草群落→长芒草群落、铁杆蒿群落、达乌里胡枝子群落→白羊草群落。随着退耕地植被恢复的不断进行,Gleason指数、Margalef指数等丰富度指数以及群落Pielou指数,都呈现出先减小后增大的趋势,Simpson指数在演替初期及平衡阶段较大,群落生态优势度与物种丰富度的变化趋势相反。在群落的演替过程中,土壤有机质、全N、有效N和速效K的含量不断增加,土壤pH值和速效P含量不断减小,土壤表层密度变小,孔隙度变大。A层土壤全N、有效N含量、土壤pH值和C层土壤全N含量与物种丰富度呈显著正相关,A、C层土壤有机质含量和B层土壤速效K含量与其关系相反;B层土壤速效P的含量与群落生态优势度呈显著正相关;A、B层土壤速效K含量与植被群落盖度呈正相关关系,B层土壤速效P含量与其关系相反。

       

      Abstract: To supply vegetation restoration and reconstruction of removal lands in loess hilly-gully region with scientific basis, based on the data of Ansai in the typical loess hilly-gully region, the vegetation communities were analysed using hierarchical cluster analysis and step by step regression procedure to classify the stages of vegetation succession with natural restoration and quantitatively determine the relationship between the communities and soil environmental factors. The results showed that the stages of succession on removal lands as follows: Artemisia secoparia community-Leymus scalinus community-Stipa bungeana community Artemisia gmelinii communityLespedeza daurica community-Bothriochloa ischaemum community. Rich indexes of Gleason and Margalef and Pielou index decrease with removal time passing by at first and then increase, Simpson index is relatively bigger at the early and later balance stages, and the trend of ecological dominance of the communities is opposite to that of species rich index. The contents of soil organic matter, total N, available N and readily available K increase and that of readily available P and soil PH value decrease in the process of succession. Soil surface density decreases and soil porosity increases.There is very significantly positive correlation between the contents of total N, available N, soil pH value in the layer A and the contents of total N in the layer C and species richness, and there is very significantly negative correlation between the contents of soil organic matter in the layer A,C and the contents of soil readily available K in the layer B and species richness. There is very significant and positive correlation between the contents of soil readily available P in the layer B and ecological dominance of the community. There is very significant and positive correlation between the contents of soil readily available K in the layer A,B and vegetation coverage, and the relationship between the contents of soil readily available P in the layer B and vegetation coverage is on the contrary.

       

    /

    返回文章
    返回