Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
J Environ Manage. 2022 Jan 15;302(Pt B):114130. doi: 10.1016/j.jenvman.2021.114130. Epub 2021 Nov 18.
Although soil fungi play a pivotal role in determining soil ecosystematic feedbacks to afforestation, there remains a big knowledge gap in the effects of afforestation on soil fungal communities, especially at a watershed scale. In this study, the variations of soil fungal diversity and community structures under afforestation were investigated in Nanliu River Basin, where paddy field and dry farmland were converted to eucalyptus plantation at an unprecedented speed. Spatial distance along the upper, middle and lower reaches of the Basin were also considered to analyze the dominant sources of the variations. The results demonstrated that eucalyptus afforestation had little effect on soil fungal diversity but could significantly influence fungal community structures. As paddy field and dry farmland converted to eucalyptus plantation, dominant fungal phylum shifted from Ascomycota to Ascomycota and Basidiomycota. Compared with afforestation from dry farmland, much bigger variation of fungal community structures was found in afforestation from paddy field. In addition, the significant change of fungal community structures exhibited in the upper reaches was from dry farmland, while presented in the middle reaches was from paddy field. However, afforestation comprised a larger source of variation than spatial distance within the soil fungal community structures, and Fusarium, Westerdykella,Zopfiella and Scleroderma were the most sensitive genera affected by afforestation. These results showed that afforestation did not always cause soil fungal diversity change and the heterogeneity of fungal community structures under afforestation was mainly controlled by original land use practices, while spatial distance partly decided the results.
虽然土壤真菌在决定森林对土壤生态系统反馈方面起着关键作用，但在造林对土壤真菌群落的影响方面，仍存在很大的知识差距，尤其是在流域尺度上。在这项研究中，我们调查了南流河流域造林后土壤真菌多样性和群落结构的变化，在该流域，水田和旱地以前所未有的速度被改造成桉树人工林。还考虑了沿流域上游、中游和下游的空间距离，以分析变化的主要来源。结果表明，桉树造林对土壤真菌多样性影响不大，但能显著影响真菌群落结构。随着水田和旱地转化为桉树人工林，主要真菌门从子囊菌门转变为子囊菌门和担子菌门。与旱地造林相比，水田造林导致的真菌群落结构变化更大。此外，上游土壤真菌群落结构的显著变化来自旱地，而中游则来自水田。然而，造林对土壤真菌群落结构的变异的贡献大于空间距离，镰刀菌属、威斯特代克氏菌属、Zopfiella 和坚木层孔菌属是受造林影响最敏感的属。这些结果表明，造林并不总是导致土壤真菌多样性的变化，造林下真菌群落结构的异质性主要受原始土地利用方式的控制，而空间距离在一定程度上决定了结果。
