Rhizosphere priming effects on soil carbon and nitrogen dynamics among tree species with and without intraspecific competition
Rhizosphere priming effects on soil carbon and nitrogen dynamics among tree species with and without intraspecific competition
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有或没有种内竞争的树种根际启动对土壤碳氮动态的影响
DOI：
10.1111/nph.15074
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发表时间：
2018
期刊：
影响因子：
9.4
通讯作者：
Cheng Weixin
中科院分区：
文献类型：
--
作者：
Yin Liming;Dijkstra Feike A;Wang Peng;Zhu Biao;Cheng Weixin
土壤微球启动效应在调节土壤有机质矿化过程中起着重要作用。然而，树种和种内竞争对RPE的影响知之甚少。以落叶松、水曲柳和杉木3个树种为试材，研究了3个树种在2种密度下140 d的RPE值，以及种内竞争对RPE值的影响。研究结果表明，不同施肥处理对土壤有机碳（C）分解、总氮（N）矿化和净氮（N）矿化以及植物氮素净吸收的影响程度不同。物种间RPE的差异与植物生物量的差异有关。随着土壤有机碳分解的RPE增加，总氮矿化量和植物净氮吸收量增加，而净氮矿化量减少。种内竞争降低了土壤有机碳分解、氮矿化总量和净矿化量以及植物氮净吸收量的RPE，尤其是水曲柳和杉木。微生物N开采可以解释整个积极的RPE跨物种，而加强植物微生物对N的竞争可能降低了RPE种内竞争。总体而言，树种的物种特异性效应在调节RPEs的大小和机制以及种内竞争对土壤C和N动态的影响中起着重要作用。
Rhizosphere priming effects (RPEs) play a central role in modifying soil organic matter mineralization. However, effects of tree species and intraspecific competition on RPEs are poorly understood.. We investigated RPEs of three tree species (larch, ash and Chinese fir) and the impact of intraspecific competition of these species on the RPE by growing them at two planting densities for 140 d. We determined the RPE on soil organic carbon (C) decomposition, gross and net nitrogen (N) mineralization and net plant N acquisition.. Differences in the RPE among species were associated with differences in plant biomass. Gross N mineralization and net plant N acquisition increased, but net N mineralization decreased, as the RPE on soil organic C decomposition increased. Intraspecific competition reduced the RPE on soil organic C decomposition, gross and net N mineralization, and net plant N acquisition, especially for ash and Chinese fir.. Microbial N mining may explain the overall positive RPEs across species, whereas intensified plant–microbe competition for N may have reduced the RPE with intraspecific competition. Overall, the species-specific effects of tree species play an important role in modulating the magnitude and mechanisms of RPEs and the intraspecific competition on soil C and N dynamics.