Nitrogen addition has contrasting effects on particulate and mineral-associated soil organic carbon in a subtropical forest
Nitrogen addition has contrasting effects on particulate and mineral-associated soil organic carbon in a subtropical forest
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添加氮对亚热带森林中颗粒物和矿物质相关的土壤有机碳具有相反的影响
DOI：
10.1016/j.soilbio.2020.107708
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发表时间：
2020-03
影响因子：
9.7
通讯作者：
Zhu Biao
中科院分区：
文献类型：
--
作者：
Chen Jungang;Xiao Wen;Zheng Chengyang;Zhu Biao
大气氮沉降的增加对森林生态系统的碳和养分循环产生了重大影响。然而，不同的土壤有机碳（SOC）组分与不同的周转率对氮添加的反应是高度分歧的，其内在机制仍然是难以捉摸的。在这项研究中，我们探讨了表层土壤（0-10厘米）的特性和微生物群落的响应，6年的实验N添加（0，50，100和150公斤N公顷-1yr-1）在中国南方的亚热带万年青阔叶林。结果表明，施氮导致土壤酸化（pH值从5.3到4.9）。微生物生物量碳和总的微生物，细菌和真菌丰度（磷脂脂肪酸，PLFA）的N添加减少，但参与C，N和磷（P）循环的胞外酶不响应N添加。施氮对土壤中可提取的Ca ~（2+）含量有一定的降低作用，而对其它阳离子（Fe ~（3+）、Al ~（3+）、Mg ~（2+）、K ~+、Na ~+）含量无明显影响。此外，氮的添加并没有显着改变土壤的C和N的浓度。通过湿筛将土壤分为颗粒有机质（>53 μm，POM）和矿物结合有机质（<53 μm，MAOM）两部分。有趣的是，POM组分中的C通过N添加显著增加，而MAOM组分中的C通过N添加耗尽。相关性分析和结构方程模拟结果表明，氮的添加可以抑制微生物对植物输入的分解，从而导致POM组分中C的积累，而它可以减少微生物坏死物质和产物的矿物吸附，从而导致MAOM组分中C的耗尽。两者合计，我们的研究结果强调了土壤C的脆弱性，在稳定的MAOM部分，氮添加，并强调了土壤金属（特别是可提取的Ca 2+）和pH值的作用，在控制土壤C储存下，氮添加。
Increasing atmospheric nitrogen (N) deposition has substantially affected carbon (C) and nutrient cycling in forest ecosystems. However, the responses of different soil organic carbon (SOC) fractions with different turnover rates to N addition are highly divergent, and the underlying mechanisms remain elusive. In this study, we explored the responses of surface soil (0–10 cm) characteristics and microbial communities to six years of experimental N addition (0, 50, 100 and 150 kg N ha−1yr−1) in a subtropical evergreen broadleaf forest in southern China. Our results showed that N addition led to significant soil acidification (pH from 5.3 to 4.9). Microbial biomass carbon and total microbial, bacterial and fungal abundance (phospholipid fatty acid, PLFA) were reduced by N addition, but extracellular enzymes involved in C, N and phosphorus (P) cycling were not responsive to N addition. Soil extractable Ca2+concentration was depleted by N addition, while other extractable cations (Fe3+, Al3+, Mg2+, K+, Na+) were not affected. Moreover, N addition did not significantly change the C and N concentration of bulk soil. We further separated the bulk soil into particulate organic matter (>53 μm, POM) and mineral-associated organic matter (<53 μm, MAOM) fractions by wet sieving. Interestingly, C in the POM fraction was significantly increased by N addition, while C in the MAOM fraction was depleted by N addition. Correlation analysis and structural equation modeling results suggested that N addition may suppress microbial decomposition of plant inputs and thus lead to accumulation of C in the POM fraction, while it may reduce the mineral sorption of microbial necromass and products and thus cause depletion of C in the MAOM fraction. Taken together, our results highlighted the vulnerability of soil C in the stable MAOM fraction to N addition, and emphasized the role of soil metals (particularly extractable Ca2+) and pH in controlling soil C storage under N addition.
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影响因子：
4
作者：
C. Riggs;S. Hobbie;E. Bach;K. Hofmockel;Clare E. Kazanski
通讯作者：
C. Riggs;S. Hobbie;E. Bach;K. Hofmockel;Clare E. Kazanski
影响因子：
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作者：
Qiaohan Wang;Chengzhi Zheng;Xin-Yang Zhang;Zeng Faxu;A. Juan
通讯作者：
Qiaohan Wang;Chengzhi Zheng;Xin-Yang Zhang;Zeng Faxu;A. Juan
DOI：
10.1101/455071
发表时间：
2018-10
期刊：
bioRxiv
影响因子：
--
作者：
A. Malik;J. Puissant;T. Goodall;S. Allison;R. Griffiths
通讯作者：
A. Malik;J. Puissant;T. Goodall;S. Allison;R. Griffiths
富氮条件下根系动态的整体模式
影响因子：
6.4
作者：
Peng Yunfeng;Guo Dali;Yang Yuanhe
通讯作者：
Yang Yuanhe
协调氮富集对土壤碳的多重影响：植物、微生物和地球化学控制
影响因子：
8.8
作者：
Ye Chenglong;Chen Dima;Hall Steven J.;Pan Shang;Yan Xuebin;Bai Tongshuo;Guo Hui;Zhang Yi;Bai Yongfei;Hu Shuijin
通讯作者：
Hu Shuijin