Estimating Change in Sedimentary Organic Carbon Content During Mangrove Restoration in Southern China Using Carbon Isotopic Measurements  

作　　者：ZHANG Jin-Ping SHEN Cheng-De REN Hai WANG Jun HAN Wei-Dong 

机构地区：[1]Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems,South China Botanical Garden,Chinese Academy of Sciences,Guangzhou 510650(China) [2]Graduate University of Chinese Academy of Sciences,Beijing 100039(China) [3]Key Laboratory of Isotope Geochronology and Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640(China) [4]Guangdong Ocean University,Zhanjiang 524088(China)

出　　处：《Pedosphere》2012年第1期58-66,共9页土壤圈（英文版）

基　　金：Supported by the National Basic Research Program (973 Program) of China (No. 2009CB421101);the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KSCX2-SW-132);the Guangdong Sci-Tech Planning Project(Nos. 2008A030203007 and 2010B060200039)

摘　　要：Based on total carbon(C) and C isotopes in sediment cores,sedimentary organic carbon(SOC) was quantified in three types of mangrove sites(barren flat sites without mangroves,mangrove plantations,and natural mangrove forests),which were considered to represent a continuum from least restored to most restored sites in southern China.SOC densities in the barren sites,plantations,and natural forests were 90,170 and 288 Mg ha 1,respectively.We inferred that mangrove restoration increased SOC accumulation in coastal areas.At 0-70 cm depth,SOC δ 13 C values in both mangrove sites ranged from 27.37‰ to 23.07‰ and exhibited gradual enrichment with depth.In contrast,the values in the barren flat sites remained around 22.19‰ and fluctuated slightly with depth.At 0-60 cm,the 14 C ages of the SOC in the barren flat site,the natural mangrove site,and the artificial mangrove site ranged from 1 397 to 2 608,255 to 2 453,and 391 to 2 512 years BP,respectively.In both types of mangrove sites but not in the barren flat sites,the enrichment of δ 13 C with depth was related to increases in SOC decay and SOC age with depth.According to analysis of 14 C age,much of the mangrove-derived C was transported and stored at 0-60 cm depth under anaerobic conditions in both mangrove sites.The sediments of mangrove forests in southern China sequester large quantities of SOC during mangrove restoration.Based on total carbon （C） and C isotopes in sediment cores, sedimentary organic carbon （SOC） was quantified in three types of mangrove sites （barren flat sites without mangroves, mangrove plantations, and natural mangrove forests）, which were considered to represent a continuum from least restored to most restored sites in southern China. SOC densities in the barren sites, plantations, and natural forests were 90, 170 and 288 Mg ha-1, respectively. We inferred that mangrove restoration increased SOC accumulation in coastal areas. At 0- 70 cm depth, SOC δ13C values in both mangrove sites ranged from -27.37‰ to -23.07‰ and exhibited gradual enrichment with depth. In contrast, the values in the barren flat sites remained around -22.19‰ and fluctuated slightly with depth. At 0- 60 cm, the 14C ages of the SOC in the barren flat site, the natural mangrove site, and the artificial mangrove site ranged from 1 397 to 2 608, 255 to 2 453, and 391 to 2 512 years BP, respectively. In both types of mangrove sites but not in the barren flat sites, the enrichment of δ13C with depth was related to increases in SOC decay and SOC age with depth. According to analysis of 14C age, much of the mangrove-derived C was transported and stored at 0-60 cm depth under anaerobic conditions in both mangrove sites. The sediments of mangrove forests in southern China sequester large quantities of SOC during mangrove restoration.

关 键 词：artificial mangrove 14C age δ13C value natural mangrove radiocarbon 

分 类 号：S718.55[农业科学—林学] P618.13[天文地球—矿床学]