长江河口盐沼湿地酸挥发性硫化物的时空分布特征及影响因素  

Spatial and seasonal variation of acid volatile sulfide(AVS) and its influence factors in intertidal salt marsh of Yangtze River estuary

作　　者：王永杰[1] 郑祥民[1] 周立旻[1] 翟立群[1] 钱鹏[1,2] 吴永红[1,3] 

机构地区：[1]华东师范大学资源与环境科学学院地理系,上海200062 [2]南通大学地理科学学院,江苏南通226019 [3]闽江学院地理科学系,福建福州350108

出　　处：《地球化学》2012年第2期158-165,共8页Geochimica

基　　金：上海市科委项目(08DZ1207900;10DZ1200703)

摘　　要：以长江河口典型潮间带(崇明东滩湿地)不同地貌单元植被根际柱样沉积物(0~33 cm)为研究对象,探讨了长江河口潮间带表层沉积环境中酸挥发性硫化物(AVS)的时空间变化特征及其与环境因子的关系。结果表明,不同植被根际沉积物中AVS含量存在显著季节变化,表现为:互花米草大于海三棱藨草和芦苇。各采样点根际沉积物中AVS含量垂向变化为:高潮滩芦苇,随深度的增加而降低;中潮滩互花米草与海三棱藨草,随深度的增加先增大后减小,且在地面下约20 cm处显著增大。Pearson相关分析表明,沉积物中AVS含量与<16μm的颗粒物、有机碳含量及含水率之间不存在简单的正相关关系。根际沉积物中AVS含量的时空变化可能受潮汐、植被生长等因素的综合影响,其时空变化特征反映了长江河口潮滩复杂多变的氧化还原条件。与芦苇和海三棱藨草相比,入侵物种互花米草对沉积物中硫酸盐异化还原有显著影响,其可能改变了潮滩湿地生态系统原有的氧化-还原生物地球化学循环过程。In order to investigate spatial and seasonal variation of acid volatile sulfide （AVS） in salt marsh and its influence factors, several cores of the rhizosphere sediments （0-33 cm） were collected from different landforms of the intertidal zone in Dongtan wetland of Chongming Island, the Yangtze River estuary. The results demonstrate that AVS concentrations obviously vary with season in different rhizosphere sediments. AVS concentrations are greater in the rhizosphere of Spartina alterniflora than in the rhizospheres of both Scirpus mariqueter and Phragmites australis throughout the growing seasons. The distribution pattern of AVS concentrations shows a rapid decrease with depth in the rhizosphere of P. australis, but another profile, i.e. rapidly increase with depth at first and then decrease, is presented for both 5~ alterniflora and 5~ mariqueter rhizospheres. Pearson correlation analysis shows that no obvious positive correlation is observed between AVS concentrations and fine-grain particle percent （〈 16 ~tm）, T^C, and water content of sediments. Spatial and seasonal variations of AVS in the rhizosphere sediments are probably influenced by some factors, such as tide and vegetation growth. So it can be used to reveal complex redox conditions in the salt marsh of Yangtze River estuary Compared to P australis and S. mariqueter, the invading exotic species S. alterniflora has an obvious influence on the sulfate reduction in sediments, whichpossibly change the biogeochemical cycle of salt marsh ecosystem.

关 键 词：盐沼湿地 酸挥发性硫化物(AVS) 互花米草 长江河口 

分 类 号：P595[天文地球—地球化学]