沉积学报2025，Vol.43Issue(6)：2004-2014,11.DOI:10.14027/j.issn.1000-0550.2023.126
沿浦湾红树林沉积物有机碳埋藏特征及来源解析
Burial Characteristics and Source Analysis of Organic Carbon in Mangrove Sediments,Yanpu Bay,China
摘要
Abstract
[Objective]Mangroves are an important coastal blue carbon ecosystem,with a strong carbon sink func-tion that has a profound impact on the global carbon cycle.In recent years,the sources and burial characteristics of organic carbon in mangrove wetland sediments have become a hot topic at home and abroad.However,there are few studies on the sources and biogeochemical cycles of organic carbon in mangrove wetland sediments at high latitudes.[Methods]A high-resolution 210Pb chronostratigraphic framework was established in the Yanpu Bay mangrove re-search area using the 1.5 m deep column sediment collected from the mangrove as a carrier.The sediment accumula-tion rate(SAR),organic carbon accumulation rate(OCAR),potential sources of organic carbon,and their contribu-tion rates were analyzed according to the characteristics of the total organic carbon content(TOC),carbon to nitrogen ratio(C/N),median particle size(D50)and stable isotopes of carbon and nitrogen(δ13C,δ15N).[Results]The sedi-mentation rate of mangrove sediments along Yanpu Bay is approximately 2.2cm/a,and a continuous sedimentary se-quence of almost 70 years has been obtained.The particle size components are mainly silt and clay components.The proportion of different components of particle size and D50 remained unchanged with depth,and the activity of excess 210Pb was closely related to depth,indicating that the sedimentary environment was relatively stable.The average con-tent of TOC is 1.63%,while the average content of TN is 0.10%.There was a significant positive correlation between TOC and TN(R2=0.238 09),and a significant negative correlation between TOC and δ13C(R2=0.472 69),indicating that the sources of organic carbon and nitrogen in sediments were consistent,and carbon sources with lower δ13C values were the main contributors to organic carbon in sediments.According to the vertical trend of TOC content,SAR and OCAR,the sedimentary record of organic carbon can be divided into three stages:the first stage is from 1955 to 1982,the second stage is from 1982 to 2014,and the third stage is from 2014 to 2021.The SAR values ranged from 52.03 to 233.61 g/(cm2·a),with an average value of 177.68 g/(cm2·a),OCAR values ranged from 112.78 to 473.97 g/(m2·a),with an average value of 286.65 g/(m2·a).TOC and OCAR showed no significant correla-tion(R2=0.095 78),while SAR and OCAR showed a significant positive correlation(R2=0.457 66).SAR of man-grove sediments may be an important factor that affects the burial of organic carbon in sediments.According to the dis-tribution range of δ13C,δ15N and C/N values of mangrove columnar sediments,it is preliminarily concluded that the deposition of terrigenous organic matter is mainly contributed by terrigenous plants,C3 plants and organic matter in lost soil.Marine organic matter deposition is mainly caused by aquatic plants,marine phytoplankton and suspended organic particles brought by seawater perfusion.Among them,the contribution rate of mangrove litter was the highest(59.44%),followed by the average contribution rate of POM(25.91%),and the contribution rate of SOM and phyto-plankton was relatively small.The contribution rate of POM is the largest,which is mainly affected by downstream seawater injection and the upstream runoff.The water conservancy facilities are the main limiting factor of the contri-bution rate of POM.Mangrove area and POM delivery are important factors that affect the burial of organic carbon burial in sediments.[Conclusions]Mangrove sediment organic carbon in Yanpu Bay is a mixed source of marine and land,and the sources of organic carbon and nitrogen in the sediment are consistent.Mangrove plant litter is the main contributor to organic carbon in sediments.Extreme weather,natural disasters,and water conservancy projects increase the complexity of sediment organic carbon sources.The sediment mass burial rate is the main factor affecting the organic carbon burial flux of mangrove sediments along Yanpu Bay.The sediment mass burial rate is mainly affected by extreme weather such as typhoon,and the use of upstream sluices and estuarine sluices also has a signifi-cant influence on it.Through reconstruction of the organic carbon burial records of mangrove sediments in Yanpu Bay,it is found that the burial of organic carbon in mangrove sediments is greatly affected by extreme weather and water conservancy projects,forming a phased deposition process.关键词
有机碳/稳定同位素/沉积记录/特征与来源/沿浦湾Key words
organic carbon/stable isotopes/sedimentary records/characteristics and sources/Yanpu Bay分类
海洋科学引用本文复制引用
LI Bin,SHUI BoNian,YU Yang,LÜ CongCong,LI XueLi,SHANGGUAN MingZhu,WEI Zhen,HU ChengYe..沿浦湾红树林沉积物有机碳埋藏特征及来源解析[J].沉积学报,2025,43(6):2004-2014,11.基金项目
国家自然科学基金项目(42306188) （42306188）
浙江省自然科学基金项目(LQ21C030006) （LQ21C030006）
浙江省属高校基本科研业务费(2021J003) （2021J003）
浙江省大学生科技创新活动计划(2022R411A004) （2022R411A004）
国家级大学生创新创业训练计划(202310340058)[National Natural Science Foundation of China,No.42306188 （202310340058）
Natural Science Foundation of Zhejiang Province,No.LQ21C030006 （）
Basic Scientific Research Business Expenses of Zhejiang Provincial Universities,No.2021J003 （）
Zhejiang Province College Student Science and Technology Innovation Activity Plan,No.2022R411A004 （）
China National University Student Innovation&Entrepreneurship Development Program,No.202310340058] （）
