Macroalgal Solutions: Blue Carbon and Aquaculture
COMMUNITY OF IMPACT:
Baja California, Mexico
Ismael Plascencia Torres, Jesus Leyva Rivera, Minerva A. Padilla Villa, Sayuri Sagisaka Mendez, Maria Fernanda Salcedo Noriega
Our generation did not cause accelerated climate change, but we are facing its consequences and we will continue to do so as the century develops. Accelerated climate change is undoubtedly the main challenge for humanity at the present time because it impacts our social structure from many different angles: causing natural disasters, modifying natural habitats, displacing species, contributing to biodiversity loss, threatening ecosystem services which we depend on, and above all threatening the stability of small communities, such as fishing villages. As undergraduate students in the Earth Sciences and Environmental Engineering, we are concerned about the effect that accelerated climate change has had and will continue to have in our region, Baja California, and we feel a responsibility to create solutions.
For us, it is clear that the key to mitigating the effects of accelerated climate change is to reduce the concentration of greenhouse gases in the atmosphere, especially carbon dioxide (CO2). Reducing CO2 emissions is not enough,it is also necessary to remove a portion of the gases that are already dissolved in the air and in the ocean. Past research has shown that kelp forests can sequester carbon from seawater far more efficiently than land forests (between 313 and 900 gdCm- 2to- 1) (Wilmers, 2012). Additionally, kelp forests can be applied as a bioremediation technology in polluted waters and wastewaters due to their filtering capacity (Neveux, 2018). For these reasons, we consider that we should study kelps to better understand their potential as mitigators of climate change and pollution, and eventually create value with them.
The forests of macroalgae in Baja California have rapid growth rates, with some of the species growing 15 cm per day (Wilmers, 2012). However, in the last decade, there has been a significant loss of natural kelp forests due to the increase in the average seawater temperature and the arrival of sea urchin barricades (Beas-Luna, 2009).
The fishermen of Baja California depend on the macroalgae forests of the Todos Santos Bay (BTS) for their great economic and cultural importance. According to the State Fishery Chart, the five products that lead the region's income are: abalone (historically), shrimp, lobster, sea urchin and octopus (State Government of Baja California, 2015). Most of these species depend directly or indirectly on the kelp forests (Beas-Luna, 2009). Another growing industry in Ensenada is aquaculture, which depends on the extraction of kelp forests to feed the abalone (Baja California State Government, 2015). Unfortunately, aquaculture produces waste and nutrients which can run downstream to the ocean and accumulate, affecting seawater quality, depleting it of oxygen (anoxia), provoking eutrophication and water turbidity, and ultimately having a negative impact on biodiversity (Global Aquaculture Alliance, 2019).
Considering all of the above, the project we propose is an evaluation of the capacity of macroalgae as crops and biofiltrators in Todos Los Santos Bay, Ensenada, Baja California, with the intention of identifying which species would be best to grow in the natural environment. Should this assessment be successful, we would be able to clean the waters near the fish cages from aquaculture and simultaneously absorb CO2 in water through our kelp crops.
Worked to better understand the physiological and morphological characteristics of their study species, Ecklonia arborea, by working with researchers in the intertidal zone of Todos Santos Bay, Ensenada.
Developed and implemented aquaculture experiments for the evaluation of absorption of Ammonium and Urea in E.arborea. Experiments are ongoing.
Partnered with MexCal, a scientific research group that has cooperation with fishing groups in Baja California and has projects to develop trophic aquaculture. This will allow students to have a connection with the fishing community and help inform this community with their research.