油蒿群落不同恢复阶段的土壤水分空间异质性及植被特征

Spatial Heterogeneity of Soil Moisture and Vegetation Characteristics in Artemisia Ordosica Community at Different Succession Stages

[目的]分析沙地恢复不同阶段(流动沙地、半固定沙地、固定沙地)油蒿(Artemisia ordosica)群落的土壤水分空间变异规律以及植被响应特征,为荒漠地区植被恢复提供科学依据。[方法]利用经典统计学与地统计学相结合的方法进行分析。[结果](1)从流动沙地到固定沙地的演替过程中,土壤水分逐步减少,其空间结构呈现出明显的斑块状和条带状布局特点,同时沙地土壤水分空间异质性逐步增加,土壤水分在不同恢复阶段均表现出随着土层深度的增加,空间相关性逐渐增强的特征。(2)在沙地恢复过程中,油蒿种群的植被覆盖度、生物量、密度呈现逐渐增加的趋势,而植被特征的空间变异性则趋于减弱。(3)在流动沙地和固定沙地上,油蒿种群特征与土壤水分呈现显著负相关(p<0.01)。[结论]油蒿种群的植被格局在一定程度上改变了土壤水分的空间异质性与分布格局。

[Objective]The research investigated the spatial patterns of soil moisture and the responses of vegetation in Artemisia ordosica community at different succession stages（shifting dunes,semi-fixed dunes and fixed dunes）in order to provide scientific basis for vegetation restoration in desert region.[Methods]The experiment was conducted in three Artemisia ordosica communities and the data were analyzed by classical statistical and geo-statistical method.[Results]（1）In the succession of shifting dunes to fixed dunes,soil moisture of Artemisia ordosica community was gradually getting worse.And the spatial distribution of soil moisture was obviously characterized by a strip-like or patchy structure;Meanwhile the spatial variability of soil moisture was increasing.The spatial autocorrelation of soil moisture gradually increased with the increase of soil depth in all three Artemisia ordosicacommunities.（2）In the revegetation process,community coverage,biomass and density gradually increased,while spatial variation of community characteristics decreased.（3）Community characteristics of Artemisia ordosica had significantly negative correlation with soil moisture in shifting dunes and fixed dunes.[Conclusion]Vegetation pattern of Artemisia ordosicalargely influenced the spatial distribution and heterogeneity of soil moisture.