Project Watershed Releases 5 Years of Research Work on Blue Carbon
Feature by Paul Horgen, Board Chair of Project Watershed
As announced in the recent state of the climate report, July 2016 was the hottest month
on record for the globe and marked 15 consecutive months of record-breaking
temperatures. The earth is warming as a result of human activity which is causing an
increase in the levels of the greenhouse gas Carbon dioxide (CO2) in the atmosphere.
Locally, we have experienced this effect with an increase in storm events, storm surges
and flooding—and this year, the surpassing of a 100 year high water mark as indicated
by Project Watershed research.
One of the ways we can attempt to manage this climate change trend locally is to
understand how Carbon dioxide (CO2) is removed by vegetation in our local
environment. Blue Carbon refers to the long-term storage of Carbon in sediments
underlying marine and aquatic plants. The sea grass/eelgrass (Zostera marina) and
saltmarsh habitats are known to remove CO2 from the atmosphere and store Carbon in
marine and aquatic plants at very high levels compared to vegetation on land (this is
also referred as Carbon burial/storage/sequestration).
The Comox Valley Project Watershed Society has developed a community-based
protocol to allow coastal organizations in the Salish Sea to assess and identify Blue
Carbon storage opportunities in their local estuary. We developed a method to map
eelgrass and saltmarsh with minimal technical expertise yet provide very accurate
results.
"In 2010, Project Watershed began reviewing published information on Blue Carbon and
prepared a series of successful grant proposals on eelgrass, saltmarsh and blue
carbon", reflects Horgen. From 2013 to present (with an annual budget of $500,000 per
year), we have focused our restoration and research activities on estuarine restorations
of shorelines, sea grasses and kelp.
We have also conducted specific research on Blue Carbon and Carbon burial. Two
reports have been prepared, these are:
1. A Blue Carbon Pilot Project report for NAPECA (North American Partnership
for Environmental Community Action)
2. Shoreline Burial and DNA Detection of Sea Grass
Both reports can be accessed from our website http://projectwatershed.ca/estuarystewardship/komoks-estuary-projects/blue-carbon/
Our results suggest that Carbon burial is influenced by local geography and hydrology
so that different areas of the estuary buries Carbon at different rates and much of the
carbon associated with eelgrass detritus is buried in sediments below eelgrass beds,
deposited on the shore (to become buried or degraded), or carried out of the estuary.
Our reports suggest that these factors should be considered when selecting an area to
carry out Blue Carbon projects and eelgrass habitat restoration. Our Royal Roads
University MSc graduate, Angela Spooner, thesis summary recommended, “Protection
and preservation of seagrass ecosystems will have the greatest effect at preserving
global carbon stocks and limiting the release to the atmosphere of Carbon dioxide from
disturbed beds and will maintain current carbon sequestration rates”. This is crucial
when seagrass meadows are experiencing a global loss of between 0.4 and 2.5% per
year in areas with some authors reporting rates as high as 5% per year.
The history of our estuary and development along its shorelines suggest that huge areas
of tidal saltmarsh disappeared as a result of human activity and farming in the flood
plain. This means that we no longer are removing CO2 from areas lost. Project
Watershed’s restoration activities help bring back these areas that can store Carbon.
Empirical observations suggest that during storms and heavy wave action sluff eelgrass
may become buried under the stone and gravel rubble along the shoreline, and
hydrological assessments and observations on secluded shorelines have revealed major
dumps of eelgrass along these shores. In an attempt to follow where the Carbon burial
of the eelgrass occurs, we initiated a pilot study sampling sediments from shoreline and
other areas in the estuary to assess sea grass DNA distribution (a measure of Carbon
burial). We tested for the presence of eelgrass and the eelgrass unique and specific
DNA signature sequence in shoreline sediments and core samples taken from various
areas. This innovative DNA approach allows us to measure with high accuracy where
the specific sea grass DNA is buried. "This is an excellent example of how specific
expertise on our Project Watershed Board and our outreach to BC universities have led
the way to a new and novel approach in the area of Blue Carbon research" notes Paul
Horgen.
Christine Hodgson, lead scientist on the NAPECA Blue Carbon efforts, remarks "our
stewardship team learned and experienced a wide range of techniques to map
vegetation and measure Carbon in core samples taken from our local estuary”. “We
were also fortunate to apply for and receive two Pacific Institute for Climate Solutions
summer interns during 2014 and 2015” remarks technical Director Dan Bowen. During
the three years of Blue Carbon effort, Project Watershed volunteers were able to travel
to meetings sponsored by the Commission for Environmental Cooperation, a three
country effort (Canada, United States and Mexico) and to also present our work at a
number of large scientific meetings in Canada and the United States.
Sea grasses, saltmarsh shoreline areas, and kelp also make up part of the salmon
highway providing refuge for migrating fish. A healthy salmon highway provides
vegetation that supports Blue Carbon. "Recently, Project Watershed has initiated a bull
kelp restoration program to help complete the local salmon highway for the K’ómoks
Estuary, explains Project Watershed Director Bill Heath and lead on our kelp efforts.
Does kelp restoration provide another Carbon sink and Blue Carbon mechanism for
coping with coastal biogeochemical change? We hope to explore all of these ideas as
our Society moves forward with additional stewardship and research efforts.
For more information about Blue Carbon and how you can get involved visit our website
at www.projectwatershed.ca
Collecting sediment core sample from dense healthy eelgrass beds
Angela Spooner and PICS intern with eelgrass bed sediment core sample
Mature Bull Kelp Nereocystis luetkeana
Bull kelp growing on the line at Royston Kelp site 2015
Lagoon Island before saltmarsh restoration planting, Airpark 2015
Lagoon Island after restoration with saltmarsh, Airpark 2016