Phytoplankton: Is the Basis of the Food Chain Doomed?

EarthzineOriginal, SGS 2017, St. George's School

Global warming and the increase of ultraviolet (UV) radiation have damaged phytoplankton populations, which, as the basis of the ocean’s food chain, affect all other organisms in the system.

At St. George’s School (Bogotá, Colombia), 77 senior science students examined biodiversity issues using Earth observation images and information. Working groups created posters and texts in both English and Spanish. This is one of the submissions selected for publication.

Members: Alejandro Albarracín, Juanita Barrera, Natalia Cruz, Maria Alejandra Gómez, Manuelita Rivera, Cristian Rojas, Aletia Sánchez


Phytoplankton, the basis and main producer of the ocean’s food chain, has been affected by important factors such as global warming and an increase of UV radiation. Its population dynamics are a strong indicator of the overall state of the ocean and the organisms that inhabit it. How has a decline in marine biodiversity of the primary consumers in the Great Barrier Reef (GBR) such as zooplankton and krill been affected during the past 10 years due to rising oceanic temperatures and UV rays?
The GBR is well known for having a large amount of marine biodiversity compared to other places in the world. Nonetheless, global warming and increasing amounts of UV rays through the Earth’s atmosphere have caused a negative impact on factors such as oceanic temperatures, acidification and the amount of light available. These variables are key for the optimal growth of phytoplankton. For that reason, if these variables are affected, there will be major changes in the ecosystem which will prevent a normal production of phytoplankton and impact the marine biodiversity of this ecosystem. Within the affected organisms there are the krill and zooplankton which are in the same food chain as phytoplankton.