树种多样性对土壤微生物群落结构和元素生物地球化学循环的影响研究进展

森林是陆地生态系统的重要组成部分,其巨大的生产力和生态服务功能对人类的生存和发展至关重要。森林树种多样性增加能够显著提高森林生产力,关于树种多样性如何影响地下生物多样性及生态功能逐渐受到国内外学者的广泛关注。从土壤微生物及其介导的元素生物地球化学循环这一视角出发,综述了树种多样性对土壤细菌和真菌多样性、群落结构及功能的影响,提出需要进一步深入研究的方向。总体来说,树种多样性有利于增加土壤细菌生物量和多样性,是预测病原性真菌和菌根真菌多样性及群落结构的重要生物因子。树种多样性能增加土壤有机碳储量,增强森林土壤的甲烷氧化能力,并提高土壤磷周转速率及有效磷含量。关于树种多样性对森林土壤氮循环的影响需考虑多样性假说和质量比假说的相对贡献。今后应加强树种多样性对多个营养级之间相互作用的研究;关注树种多样性对生态系统多功能的影响;加强学科交叉,引入微生物种群动态模型和气候模型等模型预测方法,研究树种多样性对全球气候变化的应对机制,以期促进地上植物多样性与地下生态系统功能关系的研究,增强森林生态系统应对未来全球环境变化的能力。

Research progresses in the effects of tree species diversity on soil microbial communities and biogeochemical cycling of elements

Forest is an important component of terrestrial ecosystems. Its high productivity and ecosystem services play a key role in anthropogenic survival and development. The increases in forest tree species diversity can significantly increase forest productivity. It has been widely concerned about how tree species diversity influences the belowground biodiversity and ecosystem functioning. From the perspective of soil microorganisms and their mediated biogeochemical cycling of elements, we reviewed the effects of tree species diversity on soil bacterial and fungal diversity, community structure and ecosystem functioning, and further proposed future research directions. In general, tree species diversity is beneficial to increase soil bacterial biomass and diversity. Tree species diversity is an important bio-indicator of the diversity and community structure of pathogenic fungi and mycorrhizal fungi. Tree species diversity can increase soil organic carbon storage, and enhance soil methane oxidation capacity, as well as facilitate soil phosphorus turnover and bioavailability. The relative contribution of diversity hypothesis and mass ratio hypothesis should be taken into consideration in terms of the effects of tree species diversity on the nitrogen cycling. In the future, we should devote great efforts to the influence of tree species diversity on interactions among multiple trophic levels. Meanwhile, more attention should be paid to the effects of tree species diversity on ecosystem multifunctionality. Interdisciplinary research and modelling prediction methods, such as microbial population dynamics model and climate model, should be incorporated to explore the mechanisms of tree species diversity in response to global environmental change. This aims to promote the study on the relationship between aboveground plant diversity and belowground ecosystem functioning, and thus enhance the capacity of forest ecosystem for dealing with future global environmental change.