Effects of temperature increase and nitrogen addition on the early litter decomposition in permafrost peatlands
Effects of temperature increase and nitrogen addition on the early litter decomposition in permafrost peatlands
复制标题
升温和氮添加对多年冻土泥炭地凋落物早期分解的影响
DOI：
10.1016/j.catena.2021.105801
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发表时间：
2021-10-21
期刊：
影响因子：
6.2
通讯作者：
Du, Yu
中科院分区：
文献类型：
--
作者：
Gao, Siqi;Song, Yanyu;Du, Yu
泥炭地是全球最重要的碳汇之一，对气候变化非常敏感。凋落物分解在泥炭地固碳和养分利用中起着重要作用。为揭示多年冻土泥炭地凋落物分解对气候变暖和氮素添加的响应机制，以大兴安岭多年冻土泥炭地典型植物羊胡子草和泥炭藓为研究对象，在10 ℃和20 ℃条件下进行了54 d的凋落物分解试验。试验设3个氮素添加处理（CK：0 mg Ng（-1），N1：2.5 mg Ng（-1），N2：5 mg Ng（-1））。结果表明，E.温度的升高显著促进了泥炭藓凋落物的分解和CO2的排放。vaginatwn和泥炭藓。N的加入促进了E. N1处理促进泥炭藓凋落物的分解，N2处理抑制泥炭藓凋落物的分解。随着温度的升高，两种凋落物中的酶活性均受到抑制。细菌和真菌的丰度与E. vaginatwn和泥炭藓凋落物的分解，表明温度和施氮量对植物凋落物分解的影响主要受微生物的调节。该研究为了解和预测全球气候变化对北方泥炭地植物凋落物分解的影响提供了理论依据。
As one kind of the most important carbon (C) sink in the world, peatlands are sensitive to climate change. The decomposition of litter plays an important role in C fixation and nutrient utilization in peatlands. To reveal the mechanism of response of the litter decomposition to climate warming and the addition of nitrogen (N) in permafrost peatlands, we selected two typical plants, Eriophorum vaginatum and Sphagnum palustre, in the permafrost peatland of Da Xing' anling Mountains, China, as the research objects and conducted a 54-day litter decomposition experiment at 10 degrees C and 20 degrees C. Three N addition treatments (CK: 0 mg N g(-1), N1: 2.5 mg N g(-1) and N2: 5 mg N g(-1)) were established. Our results showed that the E. vaginatwn litter decomposed more quickly than that of Sphagnum, and an increase in temperature significantly promoted the litter decomposition and CO2 emission of E. vaginatwn and Sphagnum. The addition of N promoted the decomposition of E. vaginatum litter, whereas the decomposition of Sphagnum litter was promoted by the N1 treatment but was inhibited by the N2 treatment. The enzyme activity in both types of litter was inhibited with the increase in temperature. The abundances of bacteria and fungi positively correlated with the decomposition constant and mean CO2 release rate by E. vaginatwn and Sphagnum litter, indicating that the effects of temperature and N addition on the decomposition of plant litter were primarily regulated by microorganisms. This study provides a theoretical basis to understand and predict the effects of global climate change on the decomposition of plant litter in boreal peatlands.