LargeCO(2)release and tidal flushing in salt marsh crab burrows reduce the potential for blue carbon sequestration

Xiao, Kai1; Wilson, Alicia M.2; Li, Hailong1; Santos, Isaac R.3,4; Tamborski, Joseph5,6; Smith, Erik2; Lang, Susan Q.2; Zheng, Chunmiao1; Luo, Xin7; Lu, Meiqing7; Correa, Rogger E.3

2020-09-04

10.1002/lno.11582

LIMNOLOGY AND OCEANOGRAPHY   影响因子和分区

0024-3590

1939-5590

Abundant crab burrows in carbon-rich, muddy salt marsh soils act as preferential water flow conduits, potentially enhancing carbon transport across the soil-water interface. With increasing recognition of blue carbon systems (salt marshes, mangroves, and seagrass) as hotspots of soil carbon sequestration, it is important to understand drivers of soil carbon cycling and fluxes. We conducted field observations and flow modeling to assess how crab burrows drive carbon exchange over time scales of minutes to weeks in an intertidal marsh in South Carolina. Results showed that continuous advective porewater exchange between the crab burrows and the surrounding soil matrix occurs because of tidally driven hydraulic gradients. The concentrations of dissolved inorganic (DIC) and organic (DOC) carbon in crab burrow porewater differ with that in the surrounding soil matrix, implying a diffusive C flux in the low-permeability marsh soil. Gas-phase concentrations of CO(2)in similar to 300 crab burrows were approximately six times greater than ambient air. The estimated total C export rate via porewater exchange (1.0 +/- 0.7 g C m(-2)d(-1)) was much greater than via passive diffusion transport (6.7 +/- 2 mg C m(-2)d(-1)) and gas-phase CO(2)release (1.8 mg C m(-2)d(-1)). The burrow-related carbon export was comparable to the regional salt marsh DIC export, groundwater-derived DIC export, and the net primary production previously estimated using ecosystem-scale approaches. These insights reveal how crab burrows modify blue carbon sequestration in salt marshes and contribute to coastal carbon budgets.

SCI

英语

第一 ; 通讯

National Natural Science Foundation of China[41907162][41972260]

Marine & Freshwater Biology ; Oceanography

Limnology ; Oceanography

WOS:000565790400001

WILEY

ENVIRONMENT/ECOLOGY

Web of Science

1.Southern Univ Sci & Technol, Sch Environm Sci & Engn, State Environm Protect Key Lab Integrated Surface, Shenzhen, Peoples R China
2.Univ South Carolina, Sch Earth Ocean & Environm, Columbia, SC 29208 USA
3.Southern Cross Univ, Natl Marine Sci Ctr, Coffs Harbour, NSW, Australia
4.Univ Gothenbrug, Dept Marine Sci, Gothenburg, Sweden
5.Woods Hole Oceanog Inst, Dept Marine Chem & Geochem, Woods Hole, MA 02543 USA
6.Dalhousie Univ, Ctr Water Resources Studies, Halifax, NS, Canada
7.Univ Hong Kong, Dept Earth Sci, Hong Kong, Peoples R China

Xiao, Kai,Wilson, Alicia M.,Li, Hailong,et al. LargeCO(2)release and tidal flushing in salt marsh crab burrows reduce the potential for blue carbon sequestration[J]. LIMNOLOGY AND OCEANOGRAPHY,2020,66(1).

Xiao, Kai.,Wilson, Alicia M..,Li, Hailong.,Santos, Isaac R..,Tamborski, Joseph.,...&Correa, Rogger E..(2020).LargeCO(2)release and tidal flushing in salt marsh crab burrows reduce the potential for blue carbon sequestration.LIMNOLOGY AND OCEANOGRAPHY,66(1).

Xiao, Kai,et al."LargeCO(2)release and tidal flushing in salt marsh crab burrows reduce the potential for blue carbon sequestration".LIMNOLOGY AND OCEANOGRAPHY 66.1(2020).