应用多元统计分析方法,建立能够揭示退化喀斯特植被恢复对土壤微生态影响效果的生物学指标评价体系。研究结果表明:细菌、真菌、放线菌、微生物总数等微生物活性指标在评价土壤生物学肥力质量时具有十分重要的作用;氨化细菌数量、微生物熵、代谢熵等微生物活性指标在土壤生物学肥力评价中也具有一定的作用,但对土壤肥力质量评价的影响较小。利用土壤综合肥力指标值综合评价结果表明,不同退化喀斯特植被恢复阶段土壤生物学肥力具有明显的垂直变化特征,均表现A层〉B层的特点,这说明各恢复阶段的土壤生物学肥力具有随土壤层次加深而下降的变化趋势。同时,从裸地阶段→草本群落阶段→灌木群落阶段→乔木群落阶段,由于土壤物质循环逐渐加快,微生物活性逐渐增强,土壤生物学肥力逐步提高。
In this paper, the system of soil biological evaluating indicators that affect soil biological characteristics during degraded karst vegetation restoration is set up by applying statistical analysis method. The resuits show that the soil microbial activity indicators ( including the amount of bacteria, fungi, antinomies, total microbes, nitrifying bacteria, cellulose decomposing microbes, Nitrogen fixing bacteria, ammonification, nitrification, decomposition of cellulose, nitrogen fixation, microbial biomass carbon, basal respiration, mi- crobial community metabolism, Shannon index, Simpson index, invertase, amylase, unease, phosphatase and catalase as well aspolyphenoloxidase) play very important role to evaluate soil biological fertility quality; but the effect of ammonifiers amount, microbial quotient, metabolic quotient on the evaluation of the soil bi- ological fertility quality is quite smaller. The results of comprehensive evaluation by using soil synthetic fertility index value indicate that soil biological fertility quality has obvious vertical variation features at different recovery stages of degraded karst vegetation, displaying the variation features of layer A〉layer B. It explains that soil biological fertility quality assumes decreasing trend with the soil layer depth in different recovery stages. In addition, from the bare land stage→herbaceous community stage→shrubby community stage→arboreal community stage, the soil biological fertility is improved gradually since the soil material cycling accelerates gradually and microbial activity increases gradually.