A collaborative team led by PSRF investigated the power of sugar kelp to improve seawater conditions locally. With increasingly corrosive conditions ahead, the project tested the efficacy of using native vegetation to buffer the pH of seawater in places with important shellfish resources. The 5-year project implemented a key recommendation of the Blue Ribbon Panel on Ocean Acidification with funding from The Paul G. Allen Family Foundation, the U.S. Navy, and the involvement of world class ocean acidification (OA) scientists. Please read our Summary of Findings to learn more. Also, explore System Science Applications’s Seaweed AquaModel, developed as a part of this project to simulate kelp growth and track the effects of kelp cultivation on ocean acidification.
Our goal in this 5-year study was to investigate sugar kelp cultivation as a strategy for mitigating ocean acidification, through improved seawater conditions or by providing shelter for sensitive species.
The power of sugar kelp
To put the idea to the test, sugar kelp was cultivated at a 2.5-acre site north of the Hood Canal Bridge leased by Blue Dot Sea Farms (formerly Hood Canal Mariculture). During the growing season, kelp consumed carbon dioxide and nitrogen from the surrounding seawater - the same way that trees absorb carbon dioxide from the atmosphere. When harvested, the carbon and nitrogen that were removed from the marine environment were transformed into a variety of products.
Data, modeling, and outreach
On the assessment side, scientists at University of Washington, NOAA, and Washington Department of Natural Resources measured the effects of kelp cultivation on pH, carbonate chemistry, biology, and fish utilization. Data were then integrated into a computer model created by System Science Applications to visually illustrate the effect of kelp on seawater conditions (find the model here: http://runeasy.org/exhibits.html). On hand to help with kelp analysis and outreach was an Advisory Team packed with kelp experts and an OA specialist with Washington Sea Grant.
Summary of Findings Available
During the first year of full-scale cultivation and assessment in 2017, 14,000 lbs. of kelp was harvested in July and transported to SkyRoot Farm on Whidbey Island for direct soil enrichment trials. A second year of full-scale cultivation and assessment was completed in 2018. If you've read this and think kelp farming is exciting, it is! While kelp farming is in still in early days in Washington, look to Maine for more stories of kelp farming in action. And explore our Summary of Findings via the link in the Introductory paragraph to learn more from our investigation into the power of kelp!
IN THE MEDIA: LISTEN
- Can kelp and seagrass help oysters adapt to major ocean change? Oregon Public Broadcasting, 2018
- Could kelp help mitigate ocean acidification? Marketplace, 2018
IN THE MEDIA: READ and WATCH
- Our local seaweed is disappearing. Could farming help conserve it? KUOW’s Soundside, 2022.
- Interest in seaweed farming across Puget Sound is ‘booming’. King5, 2022.
- Will Northwest Seaweed Farming Finally Take Off? Seattle Met, 2020
- Training Builds on Growing Popularity of Kelp Farming. NOAA Fisheries, 2020
- Could seaweed be Washington’s next cash crop? Crosscut, 2019
- Food, innovation and resilience in the face of climate change. The Seattle Times, Pacific NW Magazine, 2018
- Slowing ocean acidification with kelp. The New York Times, 2016
- Studies testing kelp to ease effects of ocean acidification. The Seattle Times, 2016
- Could kelp forests keep ocean acidification at bay? Mongabay, 2016
- Research Article: Bednaršek et al. 2022. Natural Analogues in pH Variability and Predictability across the Coastal Pacific Estuaries: Extrapolation of the Increased Oyster Dissolution under Increased pH Amplitude and Low Predictability Related to Ocean Acidification. Environmental Science and Technology.
- System Science Applications’s Seaweed AquaModel
- Washington Sea Grant’s kelp aquaculture website
- The Power of Kelp: Investigating Kelp Cultivation as a Strategy for Mitigating Ocean Acidification 2-pager, 2019.
- The Power of Kelp poster. PSRF & team, 2017