Port of Los Angeles Seaweeds, Marine Plants and Differences in Carbon Sequestration
Introduction: The Port of Los Angeles and surrounding San Pedro bay area are subject to extremely high amounts of pollution from the global seaport, though the marine communities of the port complex are extremely abundant and reflect high, healthy levels of productivity. One of the main components of the port complex that supports this high biodiversity are seaweeds and marine plants. With a rocky terrain that acts as an anchor along with strong nutrient driving currents, the coastal San Pedro area is a model home for giant kelp (Macrocystis pyrifera) and feather boa kelp (Egregia menziesii)¹. Even though the nearby LA harbor is contained by a seawall, has a significant amount of dredged sandy bottom, and lacks the typical local factors needed to support macroalgae and marine plants, they are surprisingly abundant in the harbor complex. Kelp and eelgrass beds are one of the most crucial elements that support life in the harbor. They act as nurseries, provide nutrient sources for animals, support large populations of pelagic and midwater fish, and eelgrass even prevents toxic algal blooms in the harbor wetland².
The curious abundance of harbor macroalgae and its ability to support these complex communities is an indicator that the port water column is clean and extremely nutrient dense. As the different types of seaweed beds in the harbor have increased linearly in density since the 1970s, researchers have begun to note the high quality of the water contrasted with such high amounts of atmospheric pollution. This is attributed to a 60% increase in kelp life (from 2008–2018) and a mass increase in measurements of dissolved oxygen. These harbor seaweeds also have the ability to regulate inorganic and organic nutrients. Kelp is able to take in atmospheric carbon during photosynthesis, store the carbon, and sink to the seafloor as seaweed biomass, burying carbon in the sediment after sequestration is complete³. Thus, research surrounding marine carbon sequestration led to a general examination of macroalgae and plants’ role in improvement of harbor water and air quality.
As climate researchers begin to recognize seaweeds’ ability to collect atmospheric carbon, they become a question of commercial potential in the hopeful increase of green industry. The Port of LA, a global mercantile entity in the conversation regarding seaports and climate change, should have information about different types of seagrasses and their ability to trap large amounts of carbon dioxide and, in doing so, promote the future of environmental carbon sequestration.
Hypothesis: I propose that an understanding of the Carbon sequestration yields and limits in the different types of seaweeds in the Los Angeles Port complex will allow commercial and environmental emission capture projects to proceed according to the natural organization of marine communities. Environmental port management teams will also be able to make calculations using sequestration rates, timelines, and the amount of atmospheric carbon dioxide that each species can yield. I propose that this research not be limited to the collection of categorical data, but also seek to compose an accessible public database with information from the study. Though the study is localized, I posit that it may be relevant to carbon sequestration research teams or other port complexes with large amounts of naturally thriving seaweed. The Port of LA is an ideal location for this study because it differs in the types of seaweeds and marine communities. The harbor is home to wetland and rocky areas, but they are both subject to the same amounts of port pollution.
Research Plan: The experiment will be limited to three different groups of marine plants: giant kelp (Macrocystis pyrifera), feather boa kelp (Egregia menziesii), and eelgrass (Zostera marina). For the sake of in situ data collection, there will be three different environmentally appropriate locations for the farming of each species. These locations will be within the same one mile radius and therefore subject to similar conditions regarding carbon. The exact amount of atmospheric carbon is negligible, however, and the research should instead focus on creating a natural environment for sequestration⁴. Researchers will determine suitable surface area for in situ kelp/eelgrass beds by calculating an average based on naturally occurring beds. There will be three plots per three sites and the initial data will be collected between the months of January and June, capturing the port’s on and off season. The main parameters for the study are the amount of carbon dioxide collected and the unit of time per type of seaweed.
Intellectual Merit: In order to combat climate change, not only do we have to develop solutions for the ways that we use and produce energy, we need to actually remove carbon from the atmosphere. The study of these three types of seaweeds may provide relevant information for sequestration in harbors, wetlands, and intertidal areas near commercial seaports. The research collected from this experiment has the potential to serve other maritime communities faced with the same issues regarding pollution and climate change.
Broader Impact: One of the main goals for this project is prioritizing community involvement at all levels and ages. At the elementary level, the Cabrillo Marine Aquarium’s “sea scout” program would allow students between the ages of seven and 12 to visit the closest research site in the nearby wetland (¼ mile from the aquarium) and learn about the ways that eelgrass not only stores atmospheric carbon, but also acts as the base for productivity and water filtration in the wetland. Students in maritime vocational programs at the Port of Los Angeles High School would be invited to work with researchers at different sites to learn how data is collected, organized, and synthesized, i.e. from site to lab. The port, being a long-time staple field trip for LAUSD students, could work alongside the testing sites to allow kids to visit. Finally, community members who complete volunteer training hosted by the local, upcoming public environmental institute Alta-Sea would be invited to act as stewards, both advocating for the project publicly in city council meetings and doing non-scientific “heavy lifting” at research sites.
- Stolzenbach, Kevin et al. “Comprehensive Biological Surveys.” Comprehensive Biological Surveys. 1–9, ES-7. Port of Los Angeles, (2018).
- Holdaway, Jim et al. “LA Habitat Brochure.” Los Angeles and Long Beach Harbor Habitat. 8–16. (2013).
- Adam Gutride, et al. “How Kelp Naturally Combats Global Climate Change.” Science in the News. (2019).
- Filbee-Dexter, Karen, and Thomas Wernberg. “Substantial Blue Carbon in Overlooked Australian Kelp Forests.” Nature News, Nature Publishing Group, 23 July 2020, www.nature.com/articles/s41598-020-69258-7.
