文献类型：期刊文献

英文题名：Quantifying Nitrogen Uptake Preferences in Mature Tropical Plantation Trees with an In Situ Whole-Tree Paired 15N Labeling Method

作者：Bao, Terun[1,2] Wang, Ang[1,3,4] Wang, Xueyan[5] Qu, Yuying[1,3,4] Zhu, Feifei[1,3,4] Tu, Ying[1,3,4] Su, Chenxia[1,3,4] Zhang, Tao[6] Chen, Dexiang[6] Li, Yinghua[2] Fang, Yunting[1,4]

第一作者：Bao, Terun

通信作者：Wang, A[1];Li, YH[2];Wang, A[3];Wang, A[4]

机构：[1]Chinese Acad Sci, Inst Appl Ecol, CAS Key Lab Forest Ecol & Silviculture, Shenyang 110016, Peoples R China;[2]Northeastern Univ, Sch Resources & Civil Engn, Shenyang 110819, Peoples R China;[3]Natl Observat & Res Stn, Qingyuan Forest CERN, Shenyang 110016, Peoples R China;[4]Key Lab Stable Isotope Tech & Applicat, Shenyang 110016, Peoples R China;[5]Shenyang Inst Technol, Sch Energy & Water Resources, Fushun 113122, Peoples R China;[6]Chinese Acad Forestry, Res Inst Trop Forestry, Guangzhou 311400, Peoples R China

年份：2025

卷号：16

期号：12

外文期刊名：FORESTS

收录：;EI(收录号：20255219807765);Scopus(收录号：2-s2.0-105025804527);WOS:【SCI-EXPANDED(收录号:WOS:001647209200001)】；

基金：This study was supported by the National Key Research and Development Program of China (2023YFD1500800), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA28020302), the National Natural Science Foundation of China (32271671, 42507318, and 32571856), the Youth Innovation Promotion Association CAS to CW (2022194), the Natural Science Foundation of Liaoning Province (2023-MSLH-206), the Basic Research Project of the Educational Department of Liaoning Province (LJ212413201006), and the Liaoning Province Science and Technology Project (2022-JH2/101300128 and 2023012116-JH3/4500). Liaoning Provincial Science and Technology Plan Joint Program (Key Research and Development Program Project) (Grant No. 2023JH2/101800056).

语种：英文

外文关键词：mycorrhizal type; nitrate assimilation; nitrogen-fixing capacity; nitrogen uptake strategy

摘要：The nitrogen (N) uptake preferences of mature tropical trees remain poorly understood, largely because traditional hydroponic methods fail to adequately simulate field conditions. To address this, we applied an in situ whole-tree paired 15N labeling experiment to quantify N acquisition strategies in three common species of tropical plantations in southern China: Hevea brasiliensis, Pinus caribaea, and Acacia mangium. The in situ whole-tree paired 15N labeling experiment revealed distinct species-specific nitrogen uptake strategies: Hevea brasiliensis preferentially absorbed nitrate (contributing 76% to total N uptake), Pinus caribaea relied more heavily on ammonium (61%), while Acacia mangium exhibited no strong preference for either N form but demonstrated the highest N uptake rate. These findings indicate the significant role of mycorrhizal type and biological nitrogen fixation in shaping N uptake patterns. Importantly, even when accounting for the dilution by the soil nitrogen pool, nitrate still contributed 42-99% of the total nitrogen uptake across the three tree species. All three species showed a substantial capacity for nitrate assimilation, challenging the conventional view of ammonium dominance in tropical trees and providing a mechanistic basis for refining nitrogen management practices in plantation forestry.