文献类型：期刊文献

英文题名：Variations in nitrogen-15 natural abundance of plant and soil systems in four remote tropical rainforests, southern China

作者：Wang, Ang[1] Fang, Yun-Ting[2] Chen, De-Xiang[1] Koba, Keisuke[3] Makabe, Akiko[3] Li, Yi-De[1] Luo, Tu-Shou[1] Yoh, Muneoki[3]

通信作者：Chen, DX[1]

机构：[1]Chinese Acad Forestry, Res Inst Trop Forestry, Guangzhou 510520, Guangdong, Peoples R China;[2]Chinese Acad Sci, Inst Appl Ecol, State Key Lab Forest & Soil Ecol, Shenyang 110164, Peoples R China;[3]Tokyo Univ Agr & Technol, Inst Agr, Fuchu, Tokyo 1838509, Japan

年份：2014

卷号：174

期号：2

起止页码：567-580

外文期刊名：OECOLOGIA

收录：;Scopus(收录号：2-s2.0-84892842214);WOS:【SCI-EXPANDED(收录号:WOS:000330734100023)】；

基金：This study was jointly supported by the Special Research Program for Public-Welfare Forestry (no. 201104009-06), Grants-in-Aid for Scientific Research (21310008), the Program to Create an Independent Research Environment for Young Researchers from the Ministry of Education, Culture, Sports, Science and Technology, Japan, and the NEXT Program (GS008) from the Japan Society for the Promotion of Science, the State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, CAS (no. Y1SRC111J6), the Special Research Program of the Research Institute for Tropical Forestry, CAF (no. RITFYWZX2011-02), the National Natural Science Foundation of China (no. 41171040). The study was also supported by CFERN and GENE Award Funds for ecological papers. The authors wish to thank Mr. Xiaoming Fang, Mr. Jiong Li, Dr. Han Xu, Mr. Mingxian Lin, Mr. Zhang Zhou, Mr. Lai Jiang, Mr. Huai Yang and the staff of Jianfengling National Natural Reserve for their kind help in sampling and laboratory analysis.

语种：英文

外文关键词：Foliar stable nitrogen isotope ratio; Nitrogen availability; Nitrogen status; Southern China; Tropical forests

摘要：The foliar stable N isotope ratio (delta N-15) can provide integrated information on ecosystem N cycling. Here we present the delta N-15 of plant and soil in four remote typical tropical rainforests (one primary and three secondary) of southern China. We aimed to examine if (1) foliar delta N-15 in the study forests is negative, as observed in other tropical and subtropical sites in eastern Asia; (2) variation in delta N-15 among different species is smaller compared to that in many N-limited temperate and boreal ecosystems; and (3) the primary forest is more N rich than the younger secondary forests and therefore is more N-15 enriched. Our results show that foliar delta N-15 ranged from -5.1 to 1.3 aEuro degrees for 39 collected plant species with different growth strategies and mycorrhizal types, and that for 35 species it was negative. Soil NO3 (-) had low delta N-15 (-11.4 to -3.2 aEuro degrees) and plant NO3 (-) uptake could not explain the negative foliar delta N-15 values (NH4 (+) was dominant in the soil inorganic-N fraction). We suggest that negative values might be caused by isotope fractionation during soil NH4 (+) uptake and mycorrhizal N transfer, and by direct uptake of atmospheric NH3/NH4 (+). The variation in foliar delta N-15 among species (by about 6 aEuro degrees) was smaller than in many N-limited ecosystems, which is typically about or over 10 aEuro degrees. The primary forest had a larger N capital in plants than the secondary forests. Foliar delta N-15 and the enrichment factor (foliar delta N-15 minus soil delta N-15) were higher in the primary forest than in the secondary forests, albeit differences were small, while there was no consistent pattern in soil delta N-15 between primary and secondary forests.