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通过对湖南省中部地区不同石漠化程度的样地进行植被调查及土壤样品分析,并结合主成分分析方法,探讨了石漠化(RD)演替对土壤综合肥力的影响。结果表明:石漠化演替对土壤相关肥力指标有不同程度的影响,其中有机质(OM)和全氮(TN)变化规律为潜在石漠化(PRD)>轻度石漠化(LRD)>中度石漠化(MRD)>重度石漠化(SRD),其它肥力指标变化与石漠化演替方向不完全一致;石漠化演替中土壤微生物量(C、N、P)变化幅度较大,分别为251.08～124.26、31.40～69.42、2.13～4.45 mg.kg-1;土壤综合肥力大小为PRD>MRD>LRD>SRD;土壤OM、TN、全磷(TP)、阳离子交换量(CEC)、微生物量碳(MBC)、微生物量氮(MBN)、微生物量磷(MBP)、容重(BD)与综合肥力关系密切,可作为石漠化土壤肥力评价的核心指标。土壤肥力退化与石漠化演替方向基本一致,但地区差异和人为干预也对石漠化土壤肥力产生巨大影响。
Through the vegetation survey and soil sample analysis of different rocky desertification areas in the central area of Hunan Province, the effects of rocky desertification (RD) succession on the comprehensive soil fertility were discussed with the method of principal component analysis. The results showed that the succession of rocky desertification had different degrees of influence on soil fertility index, and the variation regularity of organic matter (OM) and total nitrogen (TN) were the potential rocky desertification (PRD)> mild rocky desertification (LRD) Moderate rocky desertification (MRD)> severe rocky desertification (SRD), and the changes of other fertility indices are not completely consistent with the succession of rocky desertification. The change of soil microbial biomass (C, N, P) (P> 0.05). The total soil fertility was PRD> MRD> LRD> SRD. Soil OM, TN, total phosphorus (TP), cation exchange capacity CEC, MBC, MBN, MBP and BD were closely related to comprehensive fertility, which could be used as the core index for evaluating soil fertility of rocky desertification. The degradation of soil fertility is consistent with the succession of rocky desertification, but regional differences and human intervention also have a huge impact on the soil fertility of rocky desertification.