气候变化领域集成服务门户(CCPortal): A Cross-System Comparison of Dark Carbon Fixation in Coastal Sediments

CCPortal

DOI	10.1029/2019GB006298
	A Cross-System Comparison of Dark Carbon Fixation in Coastal Sediments
	Vasquez-Cardenas D.; Meysman F.J.R.; Boschker H.T.S.
发表日期	2020
ISSN	0886-6236
EISSN	1944-9224
卷号	34 期号:2
英文摘要	Dark carbon fixation (DCF) by chemoautotrophic microorganisms can sustain food webs in the seafloor by local production of organic matter independent of photosynthesis. The process has received considerable attention in deep sea systems, such as hydrothermal vents, but the regulation, depth distribution, and global importance of coastal sedimentary DCF have not been systematically investigated. Here we surveyed eight coastal sediments by means of stable isotope probing (13C-DIC) combined with bacterial biomarkers (phospholipid-derived fatty acids) and compiled additional rates from literature into a global database. DCF rates in coastal sediments range from 0.07 to 36.30 mmol C m−2 day−1, and there is a linear relation between DCF and water depth. The CO2 fixation ratio (DCF/CO2 respired) also shows a trend with water depth, decreasing from 0.09 in nearshore environments to 0.04 in continental shelf sediments. Five types of depth distributions of chemoautotrophic activity are identified based on the mode of pore water transport (advective, bioturbated, and diffusive) and the dominant pathway of microbial sulfur oxidation. Extrapolated to the global coastal ocean, we estimate a DCF rate of 0.04 to 0.06 Pg C year−1, which is less than previous estimates based on indirect measurements (0.15 Pg C year−1), but remains substantially higher than the global DCF rate at deep sea hydrothermal vents (0.001–0.002 Pg C year−1). ©2020. The Authors.
英文关键词	Beggiatoa; bioturbation; cable bacteria; chemoautotrophy; fatty acids; salt marsh
语种	英语
scopus关键词	bioturbation; carbon fixation; chemoautotrophy; continental shelf; fatty acid; hydrothermal vent; microbial activity; porewater; saltmarsh; seafloor; stable isotope; sulfur compound; Bacteria (microorganisms); Beggiatoa
来源期刊	Global Biogeochemical Cycles
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/129671
作者单位	Department of Biotechnology, Delft University of Technology, Delft, Netherlands; Department of Biology, University of Antwerp, Antwerp, Belgium
推荐引用方式 GB/T 7714	Vasquez-Cardenas D.,Meysman F.J.R.,Boschker H.T.S.. A Cross-System Comparison of Dark Carbon Fixation in Coastal Sediments[J],2020,34(2).
APA	Vasquez-Cardenas D.,Meysman F.J.R.,&Boschker H.T.S..(2020).A Cross-System Comparison of Dark Carbon Fixation in Coastal Sediments.Global Biogeochemical Cycles,34(2).
MLA	Vasquez-Cardenas D.,et al."A Cross-System Comparison of Dark Carbon Fixation in Coastal Sediments".Global Biogeochemical Cycles 34.2(2020).