Resource Partitioning between Bacteria, Fungi, and Protists in the Detritusphere of an Agricultural Soil.
Resource Partitioning between Bacteria, Fungi, and Protists in the Detritusphere of an Agricultural Soil.
复制标题
在农业土壤的碎屑中，细菌，真菌和生物之间的资源分配。
DOI：
10.3389/fmicb.2016.01524
复制
发表时间：
2016
影响因子：
5.2
通讯作者：
Kandeler E
中科院分区：
文献类型：
--
作者：
Kramer S;Dibbern D;Moll J;Huenninghaus M;Koller R;Krueger D;Marhan S;Urich T;Wubet T;Bonkowski M;Buscot F;Lueders T;Kandeler E
土壤中植物源碳的流动是全球碳循环的关键组成部分。土壤营养碳通量的概念模型假设碎屑圈中存在独立的细菌和真菌能量通道，受基质复杂性和顽抗性控制。然而，对所涉及的关键人群及其之间的生态位划分的详细了解是有限的。在这里，进行了微观实验，以追踪农业土壤中底物类似物（葡萄糖、纤维素）和植物生物量改良剂（玉米叶、根）中碎屑球 C 的流动。通过 rRNA 稳定同位素探测和三个微生物界的扩增子测序来追踪碳流。放线菌门、拟杆菌门、γ变形菌门、担子菌门、子囊菌门以及霜孢菌门内的不同谱系被确定为重要的主要底物消费者。观察到主要消费者的动态连续性，尤其是在纤维素处理中，而且随着时间的推移在植物改良剂中也是如此。虽然清楚地观察到界内生态位划分，但不同的细菌和真菌能量通道并不明显。此外，虽然主要底物消费者的多样性并未随着底物复杂性而显着增加，但消费者演替和与食细菌和食真菌微生物的次要营养联系导致更顽固的底物中食物网的复杂性增加。这表明，消费者演替以及王国内和王国间的交叉喂养应被视为支持碎屑圈食物网复杂性的机制，而不是底物定义的能量通道。
The flow of plant-derived carbon in soil is a key component of global carbon cycling. Conceptual models of trophic carbon fluxes in soil have assumed separate bacterial and fungal energy channels in the detritusphere, controlled by both substrate complexity and recalcitrance. However, detailed understanding of the key populations involved and niche-partitioning between them is limited. Here, a microcosm experiment was performed to trace the flow of detritusphere C from substrate analogs (glucose, cellulose) and plant biomass amendments (maize leaves, roots) in an agricultural soil. Carbon flow was traced by rRNA stable isotope probing and amplicon sequencing across three microbial kingdoms. Distinct lineages within the Actinobacteria, Bacteroidetes, Gammaproteobacteria, Basidiomycota, Ascomycota as well as Peronosporomycetes were identified as important primary substrate consumers. A dynamic succession of primary consumers was observed especially in the cellulose treatments, but also in plant amendments over time. While intra-kingdom niche partitioning was clearly observed, distinct bacterial and fungal energy channels were not apparent. Furthermore, while the diversity of primary substrate consumers did not notably increase with substrate complexity, consumer succession and secondary trophic links to bacterivorous and fungivorous microbes resulted in increased food web complexity in the more recalcitrant substrates. This suggests that rather than substrate-defined energy channels, consumer succession as well as intra- and inter-kingdom cross-feeding should be considered as mechanisms supporting food web complexity in the detritusphere.