Spatial and temporal variations of sedimented organic matter in Xiaohai Lagoon,Hainan Island

作     者：LIU Xingjian GE Chendong 

作者机构：Ministry of Education Key Laboratory for Coast and Island DevelopmentNanjing UniversityNanjing 210093China School of Geographic and Oceanographic SciencesNanjing UniversityNanjing 210093China 

出 版 物：《Acta Oceanologica Sinica》 (海洋学报（英文版）)

年 卷 期：2012年第31卷第3期

页      面：74-86页

核心收录：

学科分类：07[理学] 

基　　金：The National Natural Science Foundation of China (NSFC) under contract No. 40376014 a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions 

主　　题：TOC TOC/TN ratios δ13C mean grain size sedimentation rate Xiaohai Lagoon 

摘      要：The characteristics of grain-size,total organic carbon (TOC) and total nitrogen (TN) contents,TOC/TN ratios,stable carbon isotope (δ13C) and 210Pb dating were measured in six sediment cores from the Xiaohai *** results show distinct spatial and temporal variations in sedimentation *** sediments are dominated by clayey silt,sandy silt and by silty sand in the southern,middle lagoon and the northern lagoon,*** and TN contents decline from south to *** rates,determined by 210Pb dating,tend to decrease from south to ***,the determination of sedimentation rate in the north is *** spatial variations are related to the variations in sediment sources and hydrodynamic conditions in the Xiaohai *** variations of organic matter signatures can be divided into two stages in the cores from the southern and middle *** 1988,the organic matter signatures are relatively *** contribution of terrestrial organic carbon sources varies between 60％ and 85％.After 1988,the organic matter signatures demonstrate significant *** and TN contents increase rapidly,TOC/TN ratios decrease,δ13C values shift to higher and the contribution of terrestrial organic carbon sources decreases to 40％-50％.The contributions of phytoplankton organic matter have increased in the sediment since *** aquaculture activities have had a significant impact on organic matter signatures since *** sedimentation rates have increased rapidly in the southern and middle lagoon since 1988 due to the anthropogenic activities which include aquaculture,mining and *** activities have caused eutrophication and increased siltation in the southern and middle lagoon.