Archive for seagrass

Gulf of Mexico: A blue carbon hotspot of mangroves, seagrass and marshes

Posted by mmaheigan 
· Wednesday, February 20th, 2019 

The Gulf of Mexico (GoM) is an important global hotspot that comprises over 2.1615 million hectares of blue carbon habitats, including mangroves, seagrasses, and salt marshes, which collectively store 480.5 Tg of organic carbon (Corg) just in the upper 1 meter of sediment. Some of these important areas of carbon sequestration are protected or conserved, but much of the area is vulnerable, as 69 million people (US and Mexico) live within 50 miles of these blue carbon habitats, so the potential for development and subsequent habitat loss is high. In a recent study published in Science of the Total Environment, the estuaries around the GoM were delineated to determine areal extent and associated carbon stocks for all three habitats.

Figure 1: Map of blue carbon extent and stock for six sub-regions in the Gulf of Mexico estuaries and the Florida Shelf. The areal extent in hectares (ha) and associated organic carbon (Corg) stock in Tg is listed for each blue carbon system (MN = mangroves, SG = seagrass, SM = saltmarsh) in each sub-region. The underlying blue carbon map shows the distribution of mangroves (red), saltmarsh (yellow), and seagrass (blue) (used with permission from Chmura and Short, 2015).

 

Of the GoM blue carbon systems studied, mangroves sequester the most carbon, storing nearly 200 Tg Corg over 650,482 ha (Figure 1). Seagrass is ubiquitous throughout the GoM basin, spanning over 1 million ha and storing 184 Tg Corg, Salt marshes, which are predominantly found in the northwestern quadrant of the GoM account for just under 100 Tg Corg. In addition to presenting these updated blue carbon stock estimates for the GoM, this study estimates anthropogenic impacts on GoM blue carbon storage and compares GoM vs. Atlantic shoreline blue carbon habitat stocks and extents.

 

Authors:
Anitra L. Thorhaug (Yale University)
Helen M. Poulos (Wesleyan University)
Jorge López-Portillo (Instituto de Ecología Mexico)
Jordan Barr (Elder Research)
Ana Laura Lara-Domínguez (Instituto de Ecología Mexico)
Tim C. Ku (Wesleyan University)
Graeme P.Berlyn (Yale University

Seagrass carbon dynamics: Gulf of Mexico

Posted by mmaheigan 
· Thursday, March 1st, 2018 

Seagrasses have died-off in great numbers, resulting in the release of stored carbon. Seagrasses represent a substantive and relatively unconstrained North American and Caribbean Sea blue carbon sink in the tropical Western Hemisphere. Fine-scale estimates of regional seagrass carbon stocks, as well as carbon fluxes from anthropogenic disturbances and natural processes and gains in sedimentary carbon from seagrass restoration are currently lacking for the bulk of tropical Western Hemisphere seagrass systems.

To address this knowledge gap, in the subtropics and tropics, a recent study yielded estimates of organic carbon (Corg) stocks, losses, and restoration gains from several seagrass beds around the Gulf of Mexico (GoM). GoM-wide seagrass natural Corg stocks were estimated to be ~37.2–37.5Tg Corg. A unique method involving quadruplicate sampling in naturally-occurring, restored, continually-historically barren, and previously-disturbed-now-barren sites provided the first available Corg loss measurements for subtropical-tropical seagrasses. GoM Corg losses were slow, occurring over multiple years, and differed between sites, depending on disturbance type. Mean restored seagrass bed Corg stocks exceeded those of natural seagrass beds, underscoring the importance of seagrass restoration as a viable carbon sequestration strategy. For restored seagrass areas, the older the restoration site, the greater the Corg stock.

Organic carbon stocks for Gulf of Mexico sediments for the top 20 cm of sediment in always barren, impacted barren, natural seagrass, and restored seagrass sites. Natural and restored seagrass beds had significantly higher organic carbon stocks than impacted barren or always barren sediments.

Seagrass restoration appears to be an important tool for climate-change mitigation. In the USA and throughout the tropics and subtropics, restoration could reduce sedimentary carbon leakage and bolster total blue carbon stores, while facilitating increased fisheries and shoreline stability. Although well-planned and executed restoration of seagrass is more difficult than mangroves or marshes, there are >1 million hectares of degraded seagrass habitats that could be restored, which would greatly increase blue carbon sinks and support diverse marine species that rely on seagrass for habitat and food.

 

Authors:
Anitra Thorhaug (Yale School of Forestry)
Helen M. Poulos (Earth Sci., Wesleyan Univ.)
Jorge López-Portillo (Inecol, Mexico)
Timothy C.W. Ku (Earth Sci., Wesleyan Univ.)
Graeme P. Berlyn (Yale School of Forestry)

Quantifying coastal and marine ecosystem carbon storage potential for climate mitigation policy and management

Posted by mmaheigan 
· Wednesday, June 21st, 2017 

Under the increasing threat of climate change, conservation practitioners and policy makers are seeking innovative and data–driven recommendations for mitigating emissions and increasing natural carbon sinks through nature-based solutions. While the ocean and terrestrial forests, and more recently, coastal wetlands, are well known carbon sinks, there is interest in exploring the carbon storage potential of other coastal and marine ecosystems such as coral reefs, kelp forests, phytoplankton, planktonic calcifiers, krill, and teleost fish. A recent study in Frontiers in Ecology and the Environment reviewed the potential and feasibility of managing these other coastal and marine ecosystems for climate mitigation. The authors concluded, that while important parts of the carbon cycle, coral reefs, kelp forests, planktonic calcifiers, krill, and teleost fish do not represent long-term carbon stores, and in the case of fish, do not represent a sequestration pathway. Phytoplankton do sequester globally significant amounts of carbon and contribute to long-term carbon storage in the deep ocean, but there is currently no good way to manage them to increase their carbon storage capacity; additionally, the vast majority of phytoplankton is located in international waters that are outside national jurisdictions, making it very difficult to include them in current climate mitigation policy frameworks.

Comparatively, coastal wetlands (mangroves, tidal marshes, and seagrasses) effectively sequester carbon long-term (up to 10x more carbon stored per unit area than terrestrial forests with 50-90% of the stored carbon residing in the soil), and fall within clear national jurisdictions, which facilitates effective and quantifiable management actions. In addition, wetland degradation has the potential to release vast amounts of stored carbon back into the atmosphere and water column, meaning that conservation and restoration of these systems can also reduce potential emissions. The authors conclude that coastal wetland protection and restoration should be a primary focus in comprehensive climate change mitigation plans along with reducing emissions.

Authors:
Jennifer Howard (Conservation International)
Ariana Sutton-Grier (University of Maryland, NOAA)
Dorothée Herr (IUCN)
Joan Kleypas (NCAR)
Emily Landis (The Nature Conservancy)
Elizabeth Mcleod (The Nature Conservancy)
Emily Pidgeon (Conservation International)
Stefanie Simpson (Restore America’s Estuaries)

Original paper: http://onlinelibrary.wiley.com/doi/10.1002/fee.1451/full

Filter by Keyword

acidification air-sea interactions allometry AMOC Antarctica anthropogenic carbon aragonite saturation aragonite saturation state arctic argo arsenic Atlantic Atlantic modeling atmospheric CO2 atmospheric nitrogen deposition autonomous observing autonomous platforms BATS bcg-argo biogeochemical cycles biogeochemical models biological pump biological uptake biophysics bloom blooms blue carbon bottom water CaCO3 calcification calcite carbon-climate feedback carbon cycle carbon sequestration Caribbean CCS changing marine ecosystems changing ocean chemistry chemoautotroph chl a chlorophyll circulation climate change CO2 coastal and estuarine coastal carbon fluxes coastal ocean coastal oceans cobalt community composition conservation cooling effect copepod coral reefs currents DCM deep convection deep ocean deep sea coral diatoms DIC dimethylsulfide DOC domoic acid dust earth system models eddy Education Ekman transport emissions ENSO enzyme equatorial regions estuarine and coastal carbon fluxes estuary EXPORTS filter feeders filtration rates fish Fish carbon fisheries floats fluid dynamics fluorescence food web food webs forams freshening geochemistry geoengineering GEOTRACES glaciers gliders global carbon budget global warming go-ship greenhouse gas Greenland Gulf of Maine Gulf of Mexico Gulf Stream gyre harmful algal bloom high latitude human impact hydrothermal hypoxia ice age ice ages ice cores ice cover industrial onset iron iron fertilization isotopes katabatic winds kelvin waves kuroshio larvaceans lateral transport lidar ligands mangroves marine boundary layer marine snowfall marshes meltwater mesopelagic mesoscale metagenome metals methane microbes microlayer microorganisms microscale microzooplankton midwater mixed layer mixotrophy modeling models mode water formation molecular diffusion MPT multi-decade NASA net community production new technology nitrogen nitrogen fixation nitrous oxide north atlantic north pacific nutricline nutrient budget nutrient cycling nutrient flux nutrient limitation nutrients OA ocean-atmosphere ocean acidification ocean carbon uptake and storage ocean color ocean observatories ODZ oligotrophic omics OMZ open ocean organic particles overturning circulation oxygen pacific pacific ocean paleoceanography particle flux particulate organic carbon pCO2 PDO pH phosphorus photosynthesis physical processes physiology phytoplankton plankton POC polar regions pollutants prediction primary production primary productivity pteropods radioisotopes remineralization remote sensing residence time respiration rivers Rossby waves Ross Sea ROV salinity salt marsh satellite scale seagrass sea ice sea level rise seasonal patterns sediments sensors shelf system ship-based observations sinking particles size SOCCOM southern ocean south pacific speciation species oscillations subduction submesoscale subpolar subtropical subtropical gyres subtropical mode water surface ocean teleconnections temperature thermohaline thorium tidal time-series time of emergence top predators trace element trace elements trace metals trait-based transfer efficiency transient features trophic transfer tropical turbulence twilight zone upper ocean upper water column upwelling US CLIVAR validation velocity gradient ventilation vertical flux vertical migration vertical transport vertical transport/flux western boundary currents wetlands winter mixing zooplankton

Copyright © 2019 - OCB Project Office, Woods Hole Oceanographic Institution, 266 Woods Hole Rd, MS #25, Woods Hole, MA 02543 USA Phone: 508-289-2838  •  Fax: 508-457-2193  •  Email: ocb_news@us-ocb.org

link to nsflink to noaalink to WHOI

Funding for the Ocean Carbon & Biogeochemistry Project Office is provided by the National Science Foundation (NSF) and the National Aeronautics and Space Administration (NASA). The OCB Project Office is housed at the Woods Hole Oceanographic Institution.