氮负荷增强对闽江河口湿地植物-土壤系统硫分布及其转运特征的影响  

Effects of enhanced nitrogen load on total sulfur distribution and transference in plant-soil system of marsh in the Minjiang estuary

作　　者：夏星辰 孙志高[1,2,3,4] 胡星云 李亚瑾[1,2,4] 师自香 宋振阳 贺攀霏 武慧慧 XIA Xingchen;SUN Zhigao;HU Xingyun;LI Yajin;SHI Zixiang;SONG Zhenyang;He Panfei;WU Huihui(Fujian Provincial Key Laboratory for Subtropical Resources and Environment,Fujian Normal University,Fuzhou 350007;Key Laboratory of Humid Subtropical Eco˗geographical Process(Fujian Normal University),Ministry of Education,Fuzhou 350007;Institute of Geography,Fujian Normal University,Fuzhou 350004;.Wetland Ecosystem Research Station of Minjiang Estuary,National Forestry and Grassland Administration,Fuzhou 350215)

机构地区：[1]福建师范大学福建省亚热带资源与环境重点实验室,福州350007 [2]福建师范大学湿润亚热带生态地理过程教育部重点实验室,福州350007 [3]福建师范大学地理研究所,福州350007 [4]福建闽江河口湿地生态系统国家定位观测研究站(国家林业和草原局),福州350215

出　　处：《环境科学学报》2023年第6期483-493,共11页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.41971128);福建省“闽江学者奖励计划”项目。

摘　　要：选择闽江河口典型短叶茳芏(Cyperus malaccensis)湿地为研究对象,基于野外原位氮(N)负荷增强模拟实验,探讨了不同氮负荷梯度下(NL0(对照处理):0 g·m^(-2)·a^(-1);NL1(低氮处理):37.5 g·m^(-2)·a^(-1);NL2(中氮处理):50 g·m^(-2)·a^(-1);NL3(高氮处理):100 g·m^(-2)·a^(-1))湿地植物-土壤系统硫分布及其转运特征.结果表明,不同氮负荷处理下湿地土壤的TS含量整体表现为NL3>NL2>NL0>NL1(p<0.05).相较于NL0处理,NL2和NL3处理下的TS平均含量分别增加了10.02%和37.25%,而在NL1处理下其值降低了38.07%.植被生态特征是影响不同氮负荷处理下土壤TS含量分布的共性因素,而高氮负荷处理下的土壤TS含量还受到pH和EC变化的影响.氮负荷增强条件下植物不同器官的TS含量均发生了明显变化,除NL3处理下根与茎的TS含量较NL0处理升高外,其它氮负荷处理下(NL1和NL2)的各器官TS含量均降低.不同氮负荷处理下湿地植物-土壤系统的硫储量整体表现为NL3>NL2>NL0>NL1,土壤是硫库的主体;不同氮负荷处理下植物不同部分的硫储量均低于NL0处理,原因可能与氮负荷增强条件下植物的“自疏效应”以及其对硫养分的吸收与转运有关.研究发现,尽管氮负荷增强并未改变湿地植物-土壤系统的硫分配格局,但其明显改变了植物的硫养分分配状况.短叶茳芏在低氮和中氮负荷条件下可能将更多的硫养分优先分配给根系,并通过拓展地下空间和提高地下生物量的方式来适应氮负荷环境;但在高氮负荷条件下,其可能将更多硫养分优先分配给茎,并通过拓展地上空间的方式来适应氮负荷环境.The study investigated the effects of enhanced nitrogen(N)load on distribution and transference of sulfur(S)in plant-soil system in a typical Cyperus malaccensis marsh in the Minjiang estuary,with four N load levels:(NL0,no N addition,0 g·m^(-2)·a^(-1);NL1,low N addition,37.5 g·m^(-2)·a^(-1);NL2,medium N addition,50 g·m^(-2)·a^(-1);and NL3,high N addition,100 g·m^(-2)·a^(-1)).Result showed that increasing N load generally increased total S(TS)content in soil but had varying effects on TS content in different parts of plants.The contents of TS in marsh soil in different N load treatments generally followed the sequence of NL3>NL2>NL0>NL1(p<0.05).Compared with the control treatment,the average contents of TS increase by 10.02%and 37.25%,under NL2 and NL3 treatments,while decreased by 38.07%in NL1 treatment.The spatial distribution of TS contents was primarily influenced by the variations of plant ecological traits with additional influence from changes in pH and EC under high N load condition.Compared with the NL0 treatment,the contents of TS in roots and stems in the NL3 treatment generally increased,while those in the NL1 and NL2 treatments decreased greatly.Soil was found to be the main body for S stock across all treatments while S stock within organs varied greatly among treatments.The S stock in organs of plant in different N load treatments were much lower than those in the NL0 treatment,which might be related to the"self-thinning effect"of plants under N load conditions and their absorption and transport for S nutrient.This study found that although enhanced N load did not alter the S allocation pattern in plant-soil system of C.malaccensis marsh,it significantly changed the distribution of S nutrient in organs of plant.The C.malaccensis in the low and medium N load levels preferentially allocated more S nutrient to the roots as they adapted to enriched environments through belowground expansion whereas those exposed to higher loads preferred allocating more nutrients above ground through stem expan

关 键 词：全硫 氮负荷 植物-土壤系统 湿地 闽江河口 

分 类 号：X522[环境科学与工程—环境工程] X17