Plant litter chemistry alters the content and composition of organic carbon associated with soil mineral and aggregate fractions in invaded ecosystems
Plant litter chemistry alters the content and composition of organic carbon associated with soil mineral and aggregate fractions in invaded ecosystems
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DOI：
10.1111/gcb.13751
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发表时间：
2017-10
影响因子：
11.6
通讯作者：
Mioko Tamura;V. Suseela;M. Simpson;B. Powell;N. Tharayil
中科院分区：
文献类型：
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作者：
Mioko Tamura;V. Suseela;M. Simpson;B. Powell;N. Tharayil
通过输入不成比例的化学性质不同的凋落物，入侵植物可能会影响与土壤矿物和团聚体部分在一些生态系统中，他们入侵的有机物质的命运。虽然上下文依赖，这些本地生态系统受到外来植物的长期入侵可能有助于区分植物-微生物-矿物相互作用的作用，从更广泛的土壤和气候的影响，土壤有机质（SOM）的形成。我们假设，土壤受到长期入侵的外来植物，输入柑橘凋落物与输入不稳定凋落物的原生植被所居住的相邻土壤相比，日本虎杖（Polygonum cuspidatum）在团聚体组分中具有更大比例的植物来源碳（C），而输入不稳定凋落物的入侵者下的土壤（黄葛藤，野葛）在粉质粘土部分中微生物来源的C的比例会比接收黄葛藤凋落物的邻近土壤中的微生物来源的C的比例更大。在虎杖网站，较高的C含量在土壤下P.虎杖，与非侵入性土壤居住的草和杂类草相比，仅限于大团聚体部分，这是丰富的植物生物标志物。在这个网站的非侵入土壤中的矿物和微团聚体部分和木栓质中的大团聚体部分，木质素的丰度较高，部分原因是本地物种的根密度较大，这可能有一个压倒性的影响，对化学的地上凋落物输入。在Alzuzu站点，尽管接收了类似数量的松凋落物，但在0-5 cm土壤深度的所有粒度级中，裂叶松下的土壤具有较低的C含量。与我们的预测相反，非侵入性土壤接收黄松凋落物有一个类似的丰富的植物生物标志物在矿物和聚合物组分，可能是因为在这个网站的土壤矿物的表面积较高。与未入侵的松树林相比，植物生物标志物在P. lobata入侵土壤的团聚体组分中较低，可能表明松树衍生化合物的微生物共代谢。这些结果突出了凋落物化学，土壤生物群和矿物之间的复杂的相互作用，在介导土壤C存储在未管理的生态系统，这些相互作用是特别重要的全球变化下，可能会改变植物物种组成，从而在陆地生态系统中的凋落物投入的数量和化学。
Through the input of disproportionate quantities of chemically distinct litter, invasive plants may potentially influence the fate of organic matter associated with soil mineral and aggregate fractions in some of the ecosystems they invade. Although context dependent, these native ecosystems subjected to prolonged invasion by exotic plants may be instrumental in distinguishing the role of plant–microbe–mineral interactions from the broader edaphic and climatic influences on the formation of soil organic matter (SOM). We hypothesized that the soils subjected to prolonged invasion by an exotic plant that input recalcitrant litter (Japanese knotweed, Polygonum cuspidatum) would have a greater proportion of plant‐derived carbon (C) in the aggregate fractions, as compared with that in adjacent soil inhabited by native vegetation that input labile litter, whereas the soils under an invader that input labile litter (kudzu, Pueraria lobata) would have a greater proportion of microbial‐derived C in the silt‐clay fraction, as compared with that in adjacent soils that receive recalcitrant litter. At the knotweed site, the higher C content in soils under P. cuspidatum, compared with noninvaded soils inhabited by grasses and forbs, was limited to the macroaggregate fraction, which was abundant in plant biomarkers. The noninvaded soils at this site had a higher abundance of lignins in mineral and microaggregate fractions and suberin in the macroaggregate fraction, partly because of the greater root density of the native species, which might have had an overriding influence on the chemistry of the above‐ground litter input. At the kudzu site, soils under P. lobata had lower C content across all size fractions at a 0–5 cm soil depth despite receiving similar amounts of Pinus litter. Contrary to our prediction, the noninvaded soils receiving recalcitrant Pinus litter had a similar abundance of plant biomarkers across both mineral and aggregate fractions, potentially because of the higher surface area of soil minerals at this site. The plant biomarkers were lower in the aggregate fractions of the P. lobata‐invaded soils, compared with noninvaded pine stands, potentially suggesting a microbial co‐metabolism of pine‐derived compounds. These results highlight the complex interactions among litter chemistry, soil biota, and minerals in mediating soil C storage in unmanaged ecosystems; these interactions are particularly important under global changes that may alter plant species composition and hence the quantity and chemistry of litter inputs in terrestrial ecosystems.