文献类型：期刊文献

英文题名：Contrasting nitrogen cycling between herbaceous wetland and terrestrial ecosystems inferred from plant and soil nitrogen isotopes across China

作者：Hu, Yu-Kun[1,2,3] Liu, Guo-Fang[2] Pan, Xu[3] Song, Yao-Bin[1] Dong, Ming[1,2,4] Cornelissen, Johannes H. C.[5]

第一作者：Hu, Yu-Kun;胡宇坤

通信作者：Song, YB[1];Dong, M[1];Dong, M[2];Dong, M[3]

机构：[1]Hangzhou Normal Univ, Coll Life & Environm Sci, Key Lab Hangzhou City Ecosyst Protect & Restorat, Hangzhou, Peoples R China;[2]Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China;[3]Chinese Acad Forestry, Inst Wetland Res, Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China;[4]Mianyang Normal Univ, Ecol Secur & Protect Key Lab Sichuan Prov, Mianyang, Sichuan, Peoples R China;[5]Vrije Univ Amsterdam, Dept Ecol Sci, Syst Ecol, Amsterdam, Netherlands

年份：2022

卷号：110

期号：6

起止页码：1259-1270

外文期刊名：JOURNAL OF ECOLOGY

收录：;Scopus(收录号：2-s2.0-85126011907);WOS:【SCI-EXPANDED(收录号:WOS:000767113600001)】；

基金：National Natural Science Foundation of China, Grant/Award Number: 31670429, 31400346, 31261120580, 31470712 and 31901149; China Scholarship Council, Grant/Award Number: 201903270009; KNAW-CEP, Grant/Award Number: 12CDP007

语种：英文

外文关键词：large environmental gradients; mycorrhizal types; nitrogen availability; nitrogen dynamics; plant functional types; plant-soil systems; stable isotopes; wetlands

摘要：Understanding nitrogen (N) cycling in different ecosystems is crucial to predicting and mitigating the global effects of altered N inputs. Although wetlands have always been assumed to differ largely from terrestrial ecosystems in N cycling, evidence from direct comparison from the field along wide environmental gradients is lacking. Here, we hypothesized strong coupling of plant and soil delta N-15 in terrestrial ecosystems due to lower N inputs and losses but weak coupling of plant and soil delta N-15 in wetlands because of higher N inputs and losses. We performed a large-scale field investigation on 26 pairs of herbaceous wetland and terrestrial sites across China covering 21 degrees of latitude and determined natural abundance of nitrogen isotopes (delta N-15) in soils and leaves of 346 dominant and subordinate plant species. We analysed the relationships between leaf and soil delta N-15 and their drivers including plant functional types in these two types of ecosystems. Plant functional types including mycorrhizal type and N-2-fixing status had consistently significant influences on leaf delta N-15 in herbaceous wetland and terrestrial ecosystems. Leaf delta N-15 increased significantly with soil delta N-15 within and across mycorrhizal types in both ecosystems, and, as hypothesized, the relationships were stronger and steeper in terrestrial than in wetland ecosystems. Moreover, leaf and soil delta N-15 were positively and significantly correlated within both N-2-fixers and non-N-2-fixers in terrestrial ecosystems and within only non-N-2-fixers in wetlands. At the community level, we also found more highly significant relationships between leaf and soil delta N-15 in terrestrial than in wetland ecosystems. Besides plant functional types, climatic and soil factors contributed to the variation in leaf delta N-15 in both ecosystems. Synthesis. Weaker relationships between plant and soil delta N-15 in wetlands at species and community levels support the hypothesis that larger N inputs and losses lead to weaker coupling in the plant-soil systems in wetlands than in terrestrial ecosystems. This provides strong evidence from a large spatial scale for contrasting N cycling in these two types of ecosystems regardless of plant functional type in terms of nutrient uptake strategy. Our findings add to our predictive power of ecosystem N dynamics under environmental changes, for example, land-use changes and elevated N inputs.