闽江河口芦苇与短叶茳芏湿地植物钴生物富集全年变化特征  

Temporal variations of cobalt bioaccumulation in marsh plants of Phragmites australis and Cyperus malaccensis in the Minjiang estuary

作　　者：师自香 孙志高[1,2,3] 李晓 胡星云[1,2] 陈冰冰[1,2,4] 李亚瑾[1,2] SHI Zixiang;SUN Zhigao;LI Xiao;HU Xingyun;CHEN Bingbing;LI Yajin(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;Wetland Ecosystem Research Station of Minjiang Estuary,National Forestry and Grassland Administration,Fuzhou 350215;College of Tourism,Resources and Environment,Zaozhuang University,Zaozhuang 277000)

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 [4]枣庄学院旅游与资源环境学院,枣庄277000

出　　处：《环境科学学报》2024年第4期356-367,共12页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金面上项目(No.41971128,42371105);福建省自然科学基金重点项目(No.2023J02012);福建省“闽江学者奖励计划”项目。

摘　　要：河口湿地位于陆海相互作用地带,是痕量有益元素的重要源、汇或转换器.在当前河口复杂环境变化及人类活动影响下,探讨湿地植物痕量有益元素的生物富集特征具有重要意义.本研究选择闽江河口鳝鱼滩的典型芦苇湿地和短叶茳芏湿地为研究对象,探讨了不同湿地植物钴(Co)生物富集的全年变化特征及其主要影响因素.结果表明,研究区湿地土壤Co含量的全年平均值((13.47±1.50)mg·kg^(-1))明显高于福建省表层土壤的背景值(7.41 mg·kg^(-1)),存在中等程度富集.芦苇和短叶茳芏湿地不同土层Co含量的全年变化特征较为相似,二者在1—4月均骤然降低,在5—9月变化不大,而在10—12月均迅速增加;除0~10 cm土层外,后者10~60 cm土层的Co含量均显著高于前者(p<0.05).植物生长节律及土层深度是影响芦苇和短叶茳芏湿地土壤Co含量时空变化的重要因素.芦苇与短叶茳芏不同器官的Co含量及富集系数(BCF_(Co))均以根最高,说明根均是二者Co的重要富集器官;二者根、叶、立枯体的BCF_(Co)在1—6月均呈先增加后降低趋势,之后至12月则呈不同波动变化,这主要与二者生长节律以及其对Co的富集能力差异有关.芦苇与短叶茳芏湿地土壤均是Co的重要储库,其占植物-土壤系统Co储量的比例均超过99.7%.研究发现,短叶茳芏不同器官的Co含量、BCF_(Co)及储量均明显高于芦苇,说明其对于Co具有更强的生物富集能力.Estuarine marshes,located in land-sea interaction zone,are important sources,sinks or converters of trace beneficial elements.As affected by complex environmental changes and human activities in estuaries,it is significance to explore the bioaccumulation for trace beneficial elements by marsh plants.To investigate the temporal variations of cobalt(Co) bioaccumulation in different marsh plants in Shanyutan of the Minjiang estuary across a year and explore its key influencing factors,the typical Phragmites australis marsh(PAM) and Cyperus malaccensis marsh(CMM) were studied.Results showed that the average Co content in marsh soils of the study region throughout a year((13.47±1.50) mg·kg^(-1)) was significantly higher than the background value in topsoil of the Fujian Province(7.41 mg·kg^(-1)),indicating moderate soil enrichment.The temporal variations of Co content in different soil layers of PAM and CMM in whole year were similar,with abrupt decrease from January to April,slight changes during May to September,and rapid increases from October to December.Except for the 0~10 cm depth,the Co contents in soils at 10~60 cm depths in the CMM were significantly higher than those in the PAM(p < 0.05).Both plant growth rhythm and soil depth influenced variations of Co contents in soils of PAM and CMM.roots of P.australis(PA) and C.malaccensis(CM) exhibited significantly higher Co accumulation and bioconcentration factor(BCF_(Co)) compared to other organs,indicating that root was an important organ for Co accumulation.The BCF_(Co) in roots,leaves and standing litters of PA and CM generally increased from January to June,followed by diverse fluctuantions,influenced by plant growth rhythm of different plants and their bioaccumulation capacities for Co.Both marsh soils of PAM and CMM acted as important reservoirs for Co,which accounted for more than 99.7% of the total Co stock in plant-soil systems.Significantly higher Co contents,stocks and BCF_(Co) of Co in organs of CM compared to PA,implying that the CM showed higher b

关 键 词：钴 生物富集 芦苇 短叶茳芏 闽江河口 

分 类 号：X14[环境科学与工程—环境科学]