DOI: 10.1029/2017GB005848
论文题名: Eutrophication Leads to Accumulation of Recalcitrant Autochthonous Organic Matter in Coastal Environment
作者: Asmala E. ; Haraguchi L. ; Markager S. ; Massicotte P. ; Riemann B. ; Staehr P.A. ; Carstensen J.
刊名: Global Biogeochemical Cycles
ISSN: 0886-6236
EISSN: 1944-9224
出版年: 2018
卷: 32, 期: 11 语种: 英语
英文关键词: anthropogenic effect
; autochthony
; coastal zone
; dissolved organic matter
; estuarine pollution
; eutrophic environment
; eutrophication
; freshwater ecosystem
; isotopic analysis
; marine ecosystem
; mixing
; nutrient cycling
; nutrient enrichment
; organic matter
; primary production
; Denmark
; Roskilde Fjord
学科: CDOM
; dissolved organic matter
; estuarine mixing
; nutrient cycling
中文摘要: Anthropogenic nutrient enrichment is changing the structure and the function of coastal ecosystems. These coastal zones are transitions between freshwater and marine systems where multiple biogeochemical processes remove, produce, and transform organic matter. The extent to which the coastal zone is merely a conduit for terrestrial (allochthonous) organic matter versus a distinct source of autochthonous organic matter fueled by eutrophication is unclear. To address this issue, we characterized the freshwater and marine dissolved organic matter (DOM) pools in a eutrophic estuary with a long water residence time (Roskilde Fjord, Denmark) over an annual cycle. We combined elemental, optical (absorbance and fluorescence), and isotopic analyses to obtain insight about the bulk properties of the DOM pool during this period. We also used sediment traps to analyze the changes related to the exchange of organic matter between the particulate organic matter and DOM fractions. The results showed that labile autochthonous DOM from in situ primary production was rapidly transformed to more recalcitrant DOM that accumulated in the estuary despite continuous exchange with the open sea. Also, parts of the particulate organic matter pool were degraded rapidly (within 24 hr) and transformed into the DOM pool. Accumulated DOM was characterized by relatively low molecular size and stable carbon isotopic value and by high protein-like fluorescence. These results indicate that autotrophic material can be a major source of specific recalcitrant DOM in eutrophic coastal waters, contributing significantly to the flux of organic carbon to the ocean. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/160180
Appears in Collections: 气候变化与战略
There are no files associated with this item.
作者单位: Tvärminne Zoological Station, University of Helsinki, Hanko, Finland; Department of Bioscience, Aarhus University, Roskilde, Denmark; Takuvik Joint International Laboratory, Université Laval and Centre National de la Recherche Scientifique, Québec, QC, Canada
Recommended Citation:
Asmala E.,Haraguchi L.,Markager S.,et al. Eutrophication Leads to Accumulation of Recalcitrant Autochthonous Organic Matter in Coastal Environment[J]. Global Biogeochemical Cycles,2018-01-01,32(11)