Evidence for involvement of keystone fungal taxa in organic phosphorus mineralization in subtropical soil and the impact of labile carbon
Evidence for involvement of keystone fungal taxa in organic phosphorus mineralization in subtropical soil and the impact of labile carbon
复制标题
关键真菌类群参与亚热带土壤有机磷矿化以及活性碳影响的证据
DOI：
10.1016/j.soilbio.2020.107900
复制
发表时间：
2020-09-01
影响因子：
9.7
通讯作者：
Sun, Bo
中科院分区：
文献类型：
--
作者：
Chen, Yan;Sun, Ruibo;Sun, Bo
土壤有机碳（SOC）通过增加有机磷（Po）在全磷中所占的比例来提高磷(P)的有效性，但SOC在将Po转化为速效磷（AP）的过程中起什么作用，以及是谁调节了Po矿化，目前尚不清楚。在本研究中，我们收集了三种不同有机（无碳、秸秆和粪肥）投入长期田间处理的土壤样品。通过比较细菌和真菌富含卵磷脂的液体培养，我们发现富含卵磷脂的真菌群落具有更高的Po矿化能力。利用高通量测序和富含卵磷脂的微生物群落，我们确定了土壤中的磷矿化类群。共现网络分析表明，真菌网络中的关键真菌类群Geastrum sp.和Chaetomium sp.与磷矿化真菌类群呈负相关，而关键细菌类群与磷矿化细菌无直接关系。研究发现，不稳定的C限制了关键真菌分类群的生长，而乳糖的添加通过增加Po矿化真菌分类群的丰度来增强Po矿化。本研究结果从群落角度强调了酸性土壤中土壤真菌对磷素矿化的重要性，并提供了易降解的碳驱动磷素矿化的证据，并通过限制关键真菌类群影响磷素有效性。我们的研究揭示了有机碳诱导真菌类群之间特定相互作用的生物学机制，并为促进磷循环提供了重要信息。
Soil organic carbon (SOC) derived from manure increase phosphorus (P) availability by increasing the proportion of organic P (Po) in total P. However, what role SOC plays in the process of converting Po to available P (AP) and who modulates Po mineralization are still poorly understood. In this study, we collected three soil samples under long-term filed treatment with different organic (no carbon, straw, and manure) inputs. By comparing bacterial and fungal lecithin-enrichment liquid cultures, we observed that the lecithin-enriched fungal community showed higher capability for Po mineralization. Using high-throughput sequencing of the field and lecithin-enriched microbial communities, we identified Po-mineralizing taxa in the soil. Co-occurrence network analysis revealed that the keystone fungal taxa Geastrum sp. and Chaetomium sp. in the fungal network negatively associated with Po-mineralizing fungal taxa, whereas keystone bacterial taxon was not directly related to Po-mineralizing bacteria. We found labile C limits the growth of keystone fungal taxa and that the addition of lactose enhanced Po mineralization by increasing the abundance of Po-mineralizing fungal taxa. Our results emphasize the importance of soil fungi for Po mineralization in acidic soil from a community perspective and provide evidence that easily degradable C drives Po mineralization and influences P availability through limitation of keystone fungal taxa. Our study gives insight into the biological mechanisms underlying specific organic carbon-induced interactions between fungal taxa and provides crucial information for the facilitation of P cycling.