土壤生物与可持续农业研究进展

农业的可持续发展是人类文明持续繁荣的重要保障。从原始农业到工业化农业的发展历程,是"自然力"不断削弱,"人为调控力"不断加强的过程。新兴的可持续农业,则希望将人为调控和自然过程协调融合,建立近自然的高效的现代农业体系。但是,面对土壤生物极高的多样性、生物和非生物过程的复杂互作及其高度的时空异质性,基于还原论的传统科学研究方法探究地下生态系统的"自然过程"困难重重。人为管理措施对农田生态过程调控的针对性和调控效果受到极大限制。尽管如此,土壤生物在生态系统服务中的作用已在世界范围内得到空前重视。如何充分发挥土壤生物在可持续农业中的作用,已成为现代农业研究领域的重要突破口。简述了土壤生物与可持续农业研究的学科发展历史,总结了农业管理措施对土壤生物及土壤食物网特征的影响,突出了土壤生物群落在可持续农业模式中土壤结构改善、土壤肥力提高和化肥农药减施等方面的积极作用;最后探讨了当前的研究难点和未来的研究方向,并对如何充分发挥土壤生物在现代农业中的贡献进行了初步的思考。认为:土壤有机质,土壤结构和土壤食物网以及三者的内在联系是可持续农业研究的关键。土壤有机质管理是调控土壤结构、土壤食物网及生态系统生产力的重要支点,但也是可持续农业模式不确定性的重要来源。基于同位素示踪等整体性分析方法,开展典型农田生态系统土壤食物网特征及其生态功能的系统研究,揭示农业模式、土壤食物网特征及生态系统生产力的关键联系,是充分发挥土壤生物在可持续农业中的积极作用的基础。

Soil biota and sustainable agriculture: A review

The sustainable development of agriculture is one of the key bases of continuous prosperity of human civilization. During the progress from primitive farming to industrial agriculture, the influences of "natural force" decreased but those of "anthropogenic regulation force" increased. The oncoming sustainable agriculture aims to integrate the two forces to establish a modern farming system which is expected being characterized by both close-to-nature and high efficiency. However, the conventional reductionism approach fails to fully explore the natural processes in belowground ecosystems due to their extremely high biodiversity, complex biotic and/or abiotic interactions, and great spatial and temporal heterogeneity. Consequently, it is difficult to develop a precision agricultural management to regulate a specific process successfully. Nevertheless, the critical contributions of soil biota to ecosystem services have now been universally recognized. It is an important cutting-edge research field of modern agriculture to fully improve the positive influences of soil biota on sustainable agriculture. In this study, we outlined the history and state-of-the-art in studies of soil biota and sustainable agriculture, summarized the impacts of agricultural management practices on the characteristics of soil biota and soil food webs. We emphasized the critical roles of soil biota community in sustainable farms for improving soil structure and soil fertility and reducing applications of chemical fertilizers and biocides. Finally, the research challenges and prospective research fields as well as the framework of improving the performance of soil biota in the modern farming systems were discussed. We considered that the key aspects in sustainable agriculture studies are soil organic matter, soil structure and soil food web, as well as the inherent connections among them. While the management of soil organic matter is the base and key point in regulating soil structure, soil food web and ecosystem productivity, however, it is also one of the most important uncertainty sources in sustainable farming. The systematical investigation of soil food web characteristics and their ecological functioning in representative agricultural ecosystems, based on application of holistic approaches such as isotope tracing, are needed. Thereby, the key connections among agricultural mode, soil food web characteristic and ecosystem productivity could be explored, and thus, the potential contributions of soil biota to sustainable agriculture could be fully stimulated.