Species shifts induce soil organic matter priming and changes in microbial communities
Species shifts induce soil organic matter priming and changes in microbial communities
复制标题
物种转变导致土壤有机质启动和微生物群落变化
DOI：
10.1016/j.scitotenv.2022.159956
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发表时间：
2023
影响因子：
9.8
通讯作者：
Mozdzer, Thomas J.
中科院分区：
文献类型：
--
作者：
Bernal, Blanca;Kim, Sunghyun;Mozdzer, Thomas J.
具有影响根际的功能性状的植物物种的入侵，如果入侵物种刺激土壤微生物群落，例如增加不稳定碳和氧的供应，则可以对土壤有机质（SOM）动态产生重大影响。我们对这些影响进行了评估，并按时间顺序进行了超过40年的研究。利用富含δ13C和δ15N的基质，我们在已建立、新入侵和原生植物群落的表层（顶部15 cm）、浅层（30-45 cm）和深层（65-80 cm）土壤中分离了som衍生和基质衍生的碳(C)和氮(N)矿化。我们发现，所有土壤都对SOM起效敏感，但不同植被群落对SOM起效的程度不同，原生组合土壤对表层土壤起效最高，而入侵植物对深层土壤起效最高。芦苇土深层功能微生物群落组成的变化，以真菌漆酶的相对丰度增加为证据，解释了这些深层入侵土壤中SOM的启动。研究结果表明，与原生植被相比，入侵芦苇维持了一个能够更快降解SOM的深层微生物群落，这表明植物物种的变化可以从根本上改变土壤生物地球化学，改变元素循环，减少SOM的停留时间。此外，我们的实验设计允许量化实时SOM-C和SOM-N总矿化，从而建立了一个有关这些湿地土壤中C和N矿化的新模型，并为SOM分解如何影响湿地N池中的N有效性和循环提供了新的见解。
Invasion of plant species with functional traits that influences the rhizosphere can have significant effects on soil organic matter (SOM) dynamics if the invasive species stimulates soil microbial communities with, for example, an enhanced supply of labile carbon and oxygen. We evaluated these effects along aPhragmitesinvasion chronosequence spanning over 40 years. Using a δ13C and δ15N enriched substrate, we separated SOM-derived and substrate-derived carbon (C) and nitrogen (N) mineralization in surface (top 15 cm), shallow (30–45 cm), and deep (65–80 cm) soils collected from established, newly invaded, and native plant communities. We found all soils were susceptible to SOM priming, but priming profiles differed between vegetation communities, being highest at the surface in native assemblage soils, whereas highest at depth under invasive plants. Changes in functional microbial community composition at depth inPhragmitessoils, evidenced by an increase in relative fungal laccase abundance, explained the SOM priming in these deep invaded soils. Our results show that invasivePhragmitesmaintains a microbial community at depth able to degrade SOM faster than that under native vegetation, evidencing that plant species shifts can fundamentally change soil biogeochemistry, altering element cycling and decreasing SOM residence time. Furthermore, our experimental design allowed to quantify real-time SOM-C and SOM-N gross mineralization, resulting in a new model relating C and N mineralization in these wetland soils and providing new insights on how SOM decomposition impacts N availability and cycling across wetland N pools.