土壤有机质周转过程及其矿物和团聚体物理调控机制

Soil organic matter turnover and controlling mechanisms of mineralogy and aggregation:new insights

土壤有机质是陆地最大的碳库,是保障土壤健康和粮食安全的基础资源,其微量变化就会对气候产生巨大的影响。全球气候变暖背景下,植被初级生产量的增加将导致输入土壤的植物凋落物和根际分泌物量增加。输入有机物驱动土壤有机质循环,其分解产物转化为新的土壤有机质,同时促进原土壤有机质分解,进而更新土壤肥力并反作用于气候变化,相关研究是土壤有机质研究的热点和重点,但是关于矿物和团聚体物理保护的研究较少。本文从生态系统角度综述了对土壤有机质周转中形成和分解过程的新认识,明确了土壤矿物和团聚体物理保护的重要性,并阐述了未来的研究方向。

Soil organic matter(SOM)is the largest terrestrial carbon pool and the fundamental resource to ensure soil health and food security.The slight change in SOM stock can cause a huge impact on climate.Global warming increases primary production and the amount of plant litter and root exudates released into soils.Plant-C input will drive the formation of new SOM through the transformation of its decomposition products and the decomposition of native SOM.These processes renew soil fertility and feedback the climate changes.Understanding the processes,driving mechanisms,and controlling factors of SOM turnover is the focus and priority of related sciences.This study reviews the recent progress on SOM turnover from an ecosystem viewpoint.It highlights the role and research needs of the physical protection by soil minerals and aggregates.