Rhizosphere stoichiometry: are C : N : P ratios of plants, soils, and enzymes conserved at the plant species-level?
Rhizosphere stoichiometry: are C : N : P ratios of plants, soils, and enzymes conserved at the plant species-level?
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DOI：
10.1111/nph.12531
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发表时间：
2014-01-01
期刊：
影响因子：
9.4
通讯作者：
Wallenstein, Matthew D.
中科院分区：
文献类型：
--
作者：
Bell, Colin;Carrillo, Yolima;Wallenstein, Matthew D.
由于土壤，植物和微生物之间的紧密联系，栖息在根际，我们假设，土壤养分和微生物的化学计量将不同的植物物种和植物根际内相关。我们评估了植物组织碳（C）：氮（N）：磷（P）的比例为8种植物代表4个不同的植物功能群在半干旱草原在近高峰生物量。使用完整的植物物种特定的根际，我们研究了土壤C：N：P，微生物生物量C：N，和土壤酶C：N：P养分收购活动。我们发现，很少有植物物种的根际表现出明显的化学计量性质，从其他植物物种和非植被土壤。C4植物布克洛和豆科植物拉氏黄芪的组织养分比和地下根际化学计量组成主要不同。C-4牧草B. daclidides根际土壤微生物碳含量较高，土壤氮含量较低，说明土壤有机质分解和养分矿化活性明显。植物根际生态化学计量学是一种高分辨率的工具，可用于将植物群落组成与地下土壤微生物和养分特征联系起来。通过确定植物物种之间的根际差异，我们可以更好地评估植物群落变化如何影响与生态系统水平过程相关的植物-微生物相互作用。
As a consequence of the tight linkages among soils, plants and microbes inhabiting the rhizosphere, we hypothesized that soil nutrient and microbial stoichiometry would differ among plant species and be correlated within plant rhizospheres. We assessed plant tissue carbon (C):nitrogen (N):phosphorus (P) ratios for eight species representing four different plant functional groups in a semiarid grassland during near-peak biomass. Using intact plant species-specific rhizospheres, we examined soil C:N:P, microbial biomass C:N, and soil enzyme C:N:P nutrient acquisition activities. We found that few of the plant species' rhizospheres demonstrated distinct stoichiometric properties from other plant species and unvegetated soil. Plant tissue nutrient ratios and components of below-ground rhizosphere stoichiometry predominantly differed between the C-4 plant species Buchloe dactyloides and the legume Astragalus laxmannii. The rhizospheres under the C-4 grass B.dactyloides exhibited relatively higher microbial C and lower soil N, indicative of distinct soil organic matter (SOM) decomposition and nutrient mineralization activities. Assessing the ecological stoichiometry among plant species' rhizospheres is a high-resolution tool useful for linking plant community composition to below-ground soil microbial and nutrient characteristics. By identifying how rhizospheres differ among plant species, we can better assess how plant-microbial interactions associated with ecosystem-level processes may be influenced by plant community shifts.