Li Zheng, Kravchenko Alexandra N, Cupples Alison, Guber Andrey K, Kuzyakov Yakov, Philip Robertson G, Blagodatskaya Evgenia
Department to Civil and Environmental Engineering, Michigan State University, East Lansing, MI, USA.
Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA.
Nat Commun. 2024 Apr 27;15(1):3578. doi: 10.1038/s41467-024-47755-x.
Delineation of microbial habitats within the soil matrix and characterization of their environments and metabolic processes are crucial to understand soil functioning, yet their experimental identification remains persistently limited. We combined single- and triple-energy X-ray computed microtomography with pore specific allocation of C labeled glucose and subsequent stable isotope probing to demonstrate how long-term disparities in vegetation history modify spatial distribution patterns of soil pore and particulate organic matter drivers of microbial habitats, and to probe bacterial communities populating such habitats. Here we show striking differences between large (30-150 µm Ø) and small (4-10 µm Ø) soil pores in (i) microbial diversity, composition, and life-strategies, (ii) responses to added substrate, (iii) metabolic pathways, and (iv) the processing and fate of labile C. We propose a microbial habitat classification concept based on biogeochemical mechanisms and localization of soil processes and also suggests interventions to mitigate the environmental consequences of agricultural management.
描绘土壤基质中的微生物栖息地，并对其环境和代谢过程进行表征，对于理解土壤功能至关重要，但对它们的实验鉴定仍然一直受到限制。我们将单能和三能X射线计算机断层扫描与用碳标记葡萄糖的孔隙特异性分配以及随后的稳定同位素探测相结合，以证明植被历史的长期差异如何改变土壤孔隙和微生物栖息地的颗粒有机物质驱动因素的空间分布模式，并探测占据此类栖息地的细菌群落。在这里，我们展示了大（直径30 - 150 µm）小（直径4 - 10 µm）土壤孔隙在以下方面的显著差异：（i）微生物多样性、组成和生命策略；（ii）对添加底物的反应；（iii）代谢途径；以及（iv）不稳定碳的处理和归宿。我们基于生物地球化学机制和土壤过程的定位提出了一种微生物栖息地分类概念，并还提出了减轻农业管理对环境影响的干预措施。
