Potential Impacts of Exogenous Nitrogen Enrichment on Distribution and Transfer of Nitrogen in Plant-Soil System of Suaeda salsa Marsh in the Yellow River Estuary, China  

作　　者：HU Xingyun SUN Zhigao YU Linying CHEN Bingbing 

机构地区：[1]Fujian Provincial Key Laboratory for Subtropical Resources and Environment,Fujian Normal University,Fuzhou 350007,China [2]Key Laboratory of Humid Subtropical Eco-Geographical Process(Fujian Normal University),Ministry of Education,Fuzhou 350007,China [3]Institute of Geography,Fujian Normal University,Fuzhou 350007,China

出　　处：《Journal of Ocean University of China》2023年第1期258-270,共13页中国海洋大学学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.41371104,41971128);the Award Program for Min River Scholar in Fujian Province(No.Min[2015]31).

摘　　要：To determine the potential impacts of exogenous nitrogen(N)enrichment on distribution and transfer of N in Suaeda salsa marsh in the Yellow River Estuary,the variations of N in plant-soil system during the growing season were investigated by field N addition experiment.The experiment included four treatments:NN(no N input treatment,0gNm^(−2) yr^(−1)),LN(low N input treatment,3.0 gNm^(−2) yr^(−1)),MN(medium N input treatment,6 gNm^(−2) yr^(−1))and HN(high N input treatment,12 gNm^(−2) yr^(−1)).Results showed that N additions generally increased the contents of total nitrogen(TN),ammonia nitrogen(NH_(4)^(+)-N)and nitrate nitrogen(NO_(3)^(−)-N)in different soil layers and the increasing trend was particularly evident in topsoil.Compared with the NN treatment,the average contents of TN in topsoil in the LN,MN and HN treatments during the growing season increased by 10.85%,30.14%and 43.98%,the mean contents of NH_(4)^(+)-N increased by 8.56%,6.96%and 14.34%,and the average contents of NO_(3)^(−)-N increased by 35.73%,45.99%and 46.66%,respectively.Although exogenous N import did not alter the temporal variation patterns of TN contents in organs,the N transfer and accumulation differed among tissues in different treatments.With increasing N import,both the N stocks in soil and plant showed increasing trend and the values in N addition treatments increased by 9.43%–38.22%and 13.40%–62.20%,respectively.It was worth noting that,compared with other treatments,the S.salsa in the MN treatments was very likely to have special response to N enrichment since not only the period of peak growth was prolonged by about 20 days but also the maximum of TN content in leaves was advanced by approximately one month.This paper found that,as N loading reached MN level in future,the growth rhythm of S.salsa and the accumulation and transference of N in its tissues would be altered significantly,which might generate great impact on the stability and health of S.salsa marsh ecosystem.

关 键 词：nitrogen import nitrogen transfer plant-soil system Suaeda salsa Yellow River Estuary 

分 类 号：Q948[生物学—植物学]