红壤侵蚀区恢复森林群落物种多样性对土壤生物学特性的影响

Species Diversity of Restored Forests and Their Effects on Soil Biological Properties in Red Soil Eroded Region

研究了南方红壤丘陵区不同森林恢复类型下生物多样性的变化,并用逐步多元回归分析法探讨了10种土壤生物学指标对多样性变化的响应。结果表明:研究样地中物种多样性以天然次生林最高。不同土壤生物学指标对物种多样性变化的响应不尽相同,其中土壤有机质、微生物生物量碳、细菌数量、真菌数量、微生物总数、脲酶、酸性磷酸酶等7个指标随着灌木物种多样性的增加而得到改善;细菌数量和酸性磷酸酶随乔木物种多样性的增加而增加;放线菌数量和多酚氧化酶随灌木个体数的增加而增加;真菌数量和酸性磷酸酶活性随乔木个体数的增加而减少;转化酶与物种多样性指数没有直接线性关系。最后建立了上述9个指标与物种多样性的相关数学模型。保护和提高南方红壤丘陵区植物群落物种多样性能促进部分土壤生物学活性指标的改善和生态功能的恢复。灌木物种多样性的恢复在人工造林恢复植被过程中应予以重视,它对于土壤生物学肥力的提高具有重要意义。

Species diversity of different forest restoration types was studied in red soil eroded region, and the responses of soil biological indicators to the changes of species diversity were also discussed with multiple regression analyses. The results showed that the restoration rate of species diversity was the fast in natural secondary. The changes of species composition for arbor, shrub and herbage were different. Soil organic matter, microbial biomass carbon, bacteria amount, fungi amount, microbial amount, urease, acid phosphatase were improved along with increasing species diversity of shrub. Bacteria amount and acid phosphatase increased with the increase of arbor species diversity. Actinomyces amount and polyphenol oxidase increased with the increase of shrub number. But fungi amount and acid phosphatase decreased with the increase of tree number. Invertase wasn't correlated with species diversity. We also developed the correlative equations of the above-mentioned 9 soil biological indicators with the species diversity indices. Protecting and increasing species diversity in red soil eroded region can improve part of soil biological indicators and promote the restoration of ecological functions. Much attention should be paid to shrub species diversity during artificial reforestation because shrub species diversity has important values for improving soil biological fertility.