Rhizosphere priming of grassland species under different water and nitrogen conditions: a mechanistic hypothesis of C-N interactions
Rhizosphere priming of grassland species under different water and nitrogen conditions: a mechanistic hypothesis of C-N interactions
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不同水氮条件下草地物种的根际启动：C-N相互作用的机制假说
DOI：
10.1007/s11104-018-3699-1
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发表时间：
2018-05
期刊：
影响因子：
4.9
通讯作者：
Cheng Weixin
中科院分区：
文献类型：
--
作者：
Lu Jiayu;Dijkstra Feike A.;Wang Peng;Cheng Weixin
根际启动效应（RPE）在土壤有机质分解和全球碳循环中起着重要作用。尽管已经研究了影响RPE的植物、土壤和环境因素，但是仍然不清楚土壤水和氮（N）状况如何一起改变RPE。我们用两种植物做了一个半自然的实验（Leymus chinnensis和Medicago sativa）在两种土壤水分水平（持水量的45%和85%）下生长，有或没有N施肥（0和10 g N m−2 y−1）。我们使用了天然的13 C丰度示踪方法测量RPE，和N预算方法测量净N矿化或immobilization.ResultsBoth积极（高达253%）和消极（下降到-21%）RPE观察到在不同的治疗组合。L.中华绒螯蟹的RPE高于M. sativa在低土壤水分条件下的根系生长，可能是由于其特殊的根系构型和根系活力。chinensis。高土壤水分显著降低了RPE，而氮肥显著增加了RPE。为了调和我们目前的结果和以前的观察与现有的个人假设有关的RPE，我们提出了一个新的假设：当N矿化占主导地位，根际输入增强RPE;当N固定占主导地位，根际输入降低RPE.ConclusionOverall，这项研究表明，RPE对土壤有机碳分解是密切相关的N过程和土壤水分状况。
Background and aimsThe rhizosphere priming effect (RPE) plays an important role in the decomposition of soil organic matter (SOM) and the global carbon cycle. Although plant, soil, and environmental factors affecting the RPE have been examined, it is still unclear how soil water and nitrogen (N) status together alter the RPE.MethodsIn order to examine plant, water, and N interacting effects on the RPE, we conducted a semi-natural experiment with two plant species (Leymus chinnensis and Medicago sativa) grown at two soil moisture levels (45 and 85% of water holding capacity) with or without N fertilization (0 and 10 g N m−2 y−1). We used a natural 13C abundance tracer method for measuring the RPE, and an N budgeting method for measuring net N mineralization or immobilization.ResultsBoth positive (up to 253%) and negative (down to −21%) RPEs were observed in different treatment combinations. L. chinensis exhibited greater RPE than M. sativa under low soil moisture, possibly due to specific root architecture and root activity of L. chinensis. High soil moisture significantly reduced the RPE, while N fertilization significantly increased the RPE. To reconcile our current results and previous observations with existing individual hypotheses related to the RPE, we put forward a new hypothesis: when N mineralization dominates, the rhizosphere input enhances the RPE; when N immobilization dominates, the rhizosphere input reduces the RPE.ConclusionOverall, this study demonstrates that the RPE on soil organic carbon decomposition is intimately linked with N processes and soil water status.
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影响因子：
9.7
作者：
B. Zhu;B. Zhu;J. Gutknecht;J. Gutknecht;D. Herman;D. Keck;D. Keck;M. Firestone;W. Cheng
通讯作者：
B. Zhu;B. Zhu;J. Gutknecht;J. Gutknecht;D. Herman;D. Keck;D. Keck;M. Firestone;W. Cheng
影响因子：
9.7
作者：
B. Zhu;W. Cheng
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B. Zhu;W. Cheng
影响因子：
9.7
作者：
J. Pausch;S. Loeppmann;Anna Kühnel;Kelsey Forbush;Y. Kuzyakov;W. Cheng
通讯作者：
J. Pausch;S. Loeppmann;Anna Kühnel;Kelsey Forbush;Y. Kuzyakov;W. Cheng
DOI：
10.2134/agronmonogr48
发表时间：
2005
期刊：
--
影响因子：
--
作者：
R. Zobel;S. Wright
通讯作者：
R. Zobel;S. Wright
影响因子：
9.7
作者：
Dijkstra, Feike A.;Bader, Nicholas E.;Cheng, Weixin
通讯作者：
Cheng, Weixin