Consistent Effects of Canopy vs. Understory Nitrogen Addition on Soil Respiration and Net Ecosystem Production in Moso Bamboo Forests
Consistent Effects of Canopy vs. Understory Nitrogen Addition on Soil Respiration and Net Ecosystem Production in Moso Bamboo Forests
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林冠与林下氮添加对毛竹林土壤呼吸和净生态系统生产的一致影响
DOI：
10.3390/f12101427
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发表时间：
2021-10
期刊：
影响因子：
2.9
通讯作者：
Tang Xiaolu
中科院分区：
文献类型：
--
作者：
Cai Chunju;Yang Zhihan;Liu Liang;Lai Yunsen;Lei Junjie;Fan Shaohui;Tang Xiaolu
氮沉降对生态系统碳循环的影响已被充分证实。然而，大多数通过直接向森林地面添加N来刺激N沉积的研究忽略了森林冠层中的一些关键生态过程（例如，氮的保留和吸收），可能不能完全代表现实的大气氮沉降及其对生态系统碳循环的影响。在这项研究中，我们模拟了冠层和林下氮沉降（50和100 kg N ha−1年−1），当地大气NHx：NOy比为2.08：1，旨在评估冠层和林下氮沉降是否对毛竹林的土壤呼吸（RS）和净生态系统生产力（NEP）具有相似的影响。结果表明，在没有氮沉降（CN 0）的情况下，RS、土壤自养（RA）和异养呼吸（RH）分别为2971 ± 597、1472 ± 579和1499 ± 56 g CO2 m−2年−1。冠层和林下氮沉降没有显着影响RS，RA和RH，冠层和林下氮沉降对这些土壤通量的影响是相似的。毛竹林的净生态效益为1940 ± 826 g CO2 m−2 year−1，是一个碳汇，表明毛竹林在减缓全球气候变化方面具有重要作用。同时，冠层和林下氮沉降对NEP的影响相似。这些研究结果并不支持先前的预测假设，林下氮沉降会高估氮沉降对碳循环的影响。然而，由于氮沉降持续时间短的限制，增加氮沉降操作的持续时间是迫切和必要的，以提高我们的理解冠层过程在生态系统碳通量的未来。
Nitrogen (N) deposition has been well documented to cause substantial impacts on ecosystem carbon cycling. However, the majority studies of stimulating N deposition by direct N addition to forest floor have neglected some key ecological processes in forest canopy (e.g., N retention and absorption) and might not fully represent realistic atmospheric N deposition and its effects on ecosystem carbon cycling. In this study, we stimulated both canopy and understory N deposition (50 and 100 kg N ha−1 year−1) with a local atmospheric NHx:NOy ratio of 2.08:1, aiming to assess whether canopy and understory N deposition had similar effects on soil respiration (RS) and net ecosystem production (NEP) in Moso bamboo forests. Results showed that RS, soil autotrophic (RA), and heterotrophic respiration (RH) were 2971 ± 597, 1472 ± 579, and 1499 ± 56 g CO2 m−2 year−1 for sites without N deposition (CN0), respectively. Canopy and understory N deposition did not significantly affect RS, RA, and RH, and the effects of canopy and understory N deposition on these soil fluxes were similar. NEP was 1940 ± 826 g CO2 m−2 year−1 for CN0, which was a carbon sink, indicating that Moso bamboo forest the potential to play an important role alleviating global climate change. Meanwhile, the effects of canopy and understory N deposition on NEP were similar. These findings did not support the previous predictions postulating that understory N deposition would overestimate the effects of N deposition on carbon cycling. However, due to the limitation of short duration of N deposition, an increase in the duration of N deposition manipulation is urgent and essential to enhance our understanding of the role of canopy processes in ecosystem carbon fluxes in the future.
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影响因子：
2.8
作者：
Houxi Zhang;Shunyao Zhuang;Bo Sun;Haibao Ji;Chang-Ming Li;Sai-xia Zhou
通讯作者：
Houxi Zhang;Shunyao Zhuang;Bo Sun;Haibao Ji;Chang-Ming Li;Sai-xia Zhou
冠层添加氮能更好地说明大气氮沉降对森林生态系统的影响吗？
影响因子：
4.6
作者：
Zhang W;Shen W;Zhu S;Wan S;Luo Y;Yan J;Wang K;Liu L;Dai H;Li P;Dai K;Zhang W;Liu Z;Wang F;Kuang Y;Li Z;Lin Y;Rao X;Li J;Zou B;Cai X;Mo J;Zhao P;Ye Q;Huang J;Fu S
通讯作者：
Fu S
影响因子：
2.7
作者：
J. Sparks
通讯作者：
J. Sparks
影响因子：
5
作者：
Changhui Peng;Zhengyong Zhao;Zhiting Zhang;Baohua Guo
通讯作者：
Baohua Guo
影响因子：
9.7
作者：
Jian, Jinshi;Steele, Meredith K.;Hodges, Steven C.
通讯作者：
Hodges, Steven C.