采用空间代替时间序列的方法，对衡阳紫色土丘陵坡地不同恢复阶段土壤微生物特征与养分的耦合关系进行研究。结果表明，1）不同恢复阶段土壤养分存在明显差异，从裸荒地阶段（Ⅰ）、草本阶段（Ⅱ）、灌木阶段（Ⅲ）到乔木阶段（Ⅳ），土壤含水量、土壤有机质、全氮、碱解氮和速效磷显著增加（P<0.05），全磷、pH 值逐渐减小（P>0.05），全钾和速效钾的差异变化不大。2）不同恢复阶段微生物总数显著增加（P<0.05），其中细菌数量显著增加（P<0.05），真菌数量的大小顺序为草本阶段（Ⅱ）>裸荒地阶段（Ⅰ）>灌木阶段（Ⅲ）>乔木阶段（Ⅳ）（P<0.05）；放线菌数量的大小顺序为草本阶段（Ⅱ）>乔木阶段（Ⅳ）>裸荒地阶段（Ⅰ）>灌木阶段（Ⅲ）（P<0.05）。裸荒地阶段（Ⅰ），细菌数量与放线菌数量呈显著正相关（P<0.05），草本阶段（Ⅱ），放线菌数量与真菌数量呈极显著正相关（P<0.01），灌木阶段（Ⅲ）和乔木阶段（Ⅳ），细菌数量、真菌数量和与放线菌数量之间呈极显著正相关关系（P<0.01）。3）相关分析表明，不同恢复阶段微生物量碳、微生物量氮和微生物量磷之间的相关性性达显著或极显著水平（P<0.05或P<0.01），土壤微生物量与土壤养分的关系密切（P<0.05或P<0.01），而微生物数量与土壤养分的相关性较弱（P>0.05）。4）典型相关分析表明，不同恢复阶段土壤微生物属性和土壤养分的耦合关系不同。裸荒地阶段（Ⅰ），土壤含水量、土壤有机质、全氮和全磷主要影响微生物量碳、微生物量氮和微生物量磷（P<0.01）。草本阶段（Ⅱ），土壤有机质、全磷和 pH 值起较大作用，主要影响微生物量碳、细菌、真菌（P<0.01）。灌木阶段（Ⅲ），土壤有机质、全磷和pH主要影响微生物量碳、微生物量氮和真菌（P<0.01）。乔木阶段（Ⅳ），全磷、碱解氮和pH值主要影响微生物量碳、微生物量氮和细菌（P<0.01）。研究结果对于构建衡阳紫色土丘陵坡地植被恢复技术体系具有理论与实践意义。%The purpose of the paper was to study the coupling relationship between soil microbe with soil nutrients in different re-vegetation stages on sloping-land with purple soils in Hengyang of Hunan Province, South-central China. We took soils of 0~20 cm depth in typical areas in bare land stage(Ⅰ), herbaceous community stage(Ⅰ), shrubby community stage(Ⅰ) and arborea community stage(Ⅳ) as our test objects by using the method of the space for time. The results showed that:1)There were obvious differences in soil nutrients in different re-vegetation stages, from Ⅰ, Ⅱ, Ⅲ to Ⅳ, SWC(Soil water content), SOM(Soil organic matter), TN(Total nitrogen), AN(Alkali-hydrolyzed nitrogen) and AP(Available phosphorus) increased significantly(P<0.05), TP(Total phosphorus), pH value decreased slighly(P>0.05), and there were no significant differences in TK(Total potassium) and AK(Available potassium);2)The number of soil microbes increased significantly(P<0.05), with a significant increase in the number of bacteria, the number of fungi were followed the order asⅡ>Ⅰ>Ⅲ>Ⅳ(P<0.05), the number of actiomycetes were followed the order as Ⅱ>Ⅳ>Ⅰ>Ⅲ(P<0.05). Ⅰ, the number of bacteria significantly positively correlated with the number of actiomycetes(P<0.05),Ⅱ, the number of actiomycetes very significantly positively correlated with the number of fungi(P<0.01),Ⅲand Ⅳ, there existed very significantly positively correlation between the number of bacteria, fungi and actiomycetes(P<0.01);3)Correlation analysis showed that there existed significantly or very significantly correlation among MBC(Microbial biomass carbon), MBN(Microbial biomass nitrogen) and MBP(Microbial biomass phosphorus)(P<0.05 or P<0.01), the relationship between soil microbial factors and soil nutrients differed in different re-vegetation stages, among which the soil microbial biomass was closely with soil nutrients(P<0.05 or P<0.01), while the amount of soil microbial population was weakly related with soil nutrients in the four re-vegetation stages(P>0.05);4)Canonical correlation analysis showed that the coupling relationships between soil microbe and soil nutrient factors were different in different re-vegetation stages.Ⅰ, SWC, SOM, TN and TP had a greater effect on MBC, MBN and MBP(P<0.01).Ⅱ, SOM, TP and pH played a greater role and mainly affected on MBC, bacteria and fungi(P<0.01).Ⅲ, SOM, TP and pH values mainly influenced MBC, MBN and fungi (P<0.01).Ⅳ, TP, AN and pH values proudly affected on MBC, MBN and bacteria(P<0.01). These would have a theoretical and practical significance for building re-vegetation technique system on sloping-land with purple soils in Hengyang of Hunan Province, South-central China.
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