Legume-microbiome interactions unlock mineral nutrients in regrowing tropical forests.
Legume-microbiome interactions unlock mineral nutrients in regrowing tropical forests.
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DOI：
10.1073/pnas.2022241118
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发表时间：
2021-03-16
影响因子：
11.1
通讯作者：
Beerling DJ
中科院分区：
文献类型：
--
作者：
Epihov DZ;Saltonstall K;Batterman SA;Hedin LO;Hall JS;van Breugel M;Leake JR;Beerling DJ
共生二氮（N2）固定树在热带森林中通过引入新的氮来实现关键功能，但它们如何克服高度风化、营养不良的热带土壤的限制尚不清楚。我们在巴拿马的田间试验中发现，热带森林中快速生长的固氮树木表现出加速的矿物风化和独特的土壤宏基因组，从而改善了它们在营养贫乏的土壤中获取无机养分的途径，从而推进了森林生物地球化学和微生物生态学的研究。此外，我们发现固氮树木对附近的非固氮树木具有类似的作用，从而忽略了以前对热带森林养分循环的全群落影响。这些结果提供了对固氮树木及其相关微生物组在保护全球生物圈内热带森林功能方面的作用的见解。豆科树木是世界范围内热带森林中丰富且功能重要的组成部分，其固氮共生关系与早期次生演替中促进生长和补充有关。然而，目前尚不清楚氮固定物如何满足养分贫乏的热带土壤上快速生物量积累对无机养分的高需求。本研究表明，在新热带次生林中，固氮树木引发的新鲜原生硅酸盐的原位风化比非固氮树木高两倍，并诱导土壤微生物群落局部增强的养分循环。来自风化矿物的鸟枪宏基因组数据支持氮和碳循环增强在增加酸度和风化中的作用。宏基因组和标记基因分析进一步揭示了氮固定物下微生物对厌氧铁还原的潜力，这是一个调节含铁土壤矿物结合的磷池的过程。我们发现土壤中铁（III）还原基因库主要由嗜酸的酸杆菌组成，其中包括大量以前未被描述过的细菌属，Candidatus Acidoferrum，属novus。铁循环基因库对pH值的依赖决定了酸性较强的固氮分子及其非固氮分子的土壤宏基因组中编码的高铁还原电位。我们推断，通过改变土壤pH值和C:N比率来促进特定的当地微生物组的活动，固氮树木可以通过增强其吸收和储存大气碳的能力的方式影响热带森林生态系统更广泛的生物地球化学功能。
Symbiotic dinitrogen (N2)-fixing trees fulfill a critical function in tropical forests by bringing in new nitrogen, yet it remains unclear how they overcome constraints by highly weathered, nutrient-poor tropical soils. We advance forest biogeochemistry and microbial ecology with the discovery from field trials in Panama that fast-growing N2-fixing trees in tropical forests exhibit accelerated mineral weathering and distinctive soil metagenomes that improve their access to inorganic nutrients in nutrient-poor soils. Furthermore, we show that N2-fixing trees exert similar effects on non-N2–fixing trees nearby thus having previously overlooked community-wide effects on tropical forest nutrient cycling. These results offer insights into the role of N2-fixing trees and their associated microbiomes in safeguarding the function of tropical forests within the global biosphere. Legume trees form an abundant and functionally important component of tropical forests worldwide with N2-fixing symbioses linked to enhanced growth and recruitment in early secondary succession. However, it remains unclear how N2-fixers meet the high demands for inorganic nutrients imposed by rapid biomass accumulation on nutrient-poor tropical soils. Here, we show that N2-fixing trees in secondary Neotropical forests triggered twofold higher in situ weathering of fresh primary silicates compared to non-N2–fixing trees and induced locally enhanced nutrient cycling by the soil microbiome community. Shotgun metagenomic data from weathered minerals support the role of enhanced nitrogen and carbon cycling in increasing acidity and weathering. Metagenomic and marker gene analyses further revealed increased microbial potential beneath N2-fixers for anaerobic iron reduction, a process regulating the pool of phosphorus bound to iron-bearing soil minerals. We find that the Fe(III)-reducing gene pool in soil is dominated by acidophilic Acidobacteria, including a highly abundant genus of previously undescribed bacteria, Candidatus Acidoferrum, genus novus. The resulting dependence of the Fe-cycling gene pool to pH determines the high iron-reducing potential encoded in the metagenome of the more acidic soils of N2-fixers and their nonfixing neighbors. We infer that by promoting the activities of a specialized local microbiome through changes in soil pH and C:N ratios, N2-fixing trees can influence the wider biogeochemical functioning of tropical forest ecosystems in a manner that enhances their ability to assimilate and store atmospheric carbon.
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影响因子：
4.4
作者：
Bloethe, Marco;Akob, Denise M.;Kuesel, Kirsten
通讯作者：
Kuesel, Kirsten
N(2)固定热带豆科植物的进化：新生代风化增强的一个贡献者？
DOI：
10.1098/rspb.2017.0370
发表时间：
2017-08-16
期刊：
Proceedings. Biological sciences
影响因子：
--
作者：
Epihov DZ;Batterman SA;Hedin LO;Leake JR;Smith LM;Beerling DJ
通讯作者：
Beerling DJ
影响因子：
3.7
作者：
Cools, N.;Vesterdal, L.;Hansen, K.
通讯作者：
Hansen, K.
影响因子：
4
作者：
Chacon, N;Silver, WL;Cusack, DF
通讯作者：
Cusack, DF
影响因子：
4.8
作者：
Bala, A;Murphy, PJ;Giller, KE
通讯作者：
Giller, KE