Can tropical phytoplankton adapt to rising ocean temperatures?
Sometimes the smaller things in life can go unnoticed. Microorganisms, along with every other marine organism in the ocean, will be greatly affected by climate change. One study aims to discover how microorganisms in the tropics will adapt to rising ocean temperatures. By sampling phytoplankton off the coast on the Big Island of Hawaii, scientists hope to gain insight into the resilience and adaptation rates of phytoplankton in this tropical region.
Why tropical phytoplankton?
For starters, diverse phytoplankton are the backbones of processes in the ocean such as food webs, nutrient cycles of iron and phosphate, as well as carbon and nitrogen inventories [1]. Specifically, in the tropics, phytoplankton are at the greatest risk for loss of diversity. Phytoplankton have preferred temperatures for development known as their optimum temperatures [2]. The optimum temperature is situated closely to the average temperature of the phytoplankton’s environment. If climates exceed a phytoplankton strain’s optimum temperature, the strains development and diversity begin to sharply decline.
Under current ocean warming trends of about two degrees Celsius, approximately one-third of present-day tropical strains are unlikely to persist in 2100 [2]. Therefore, rising temperatures in the tropic zones are likely to have the strongest effect on tropical strains [2], unless they are capable of adapting to a warmer ocean climate.
The study will utilize two tanks to test their theories of phytoplankton adaptation. One tank will be controlled to the temperatures of the current tropical environment. The other tank will be subjected to gradually temperature increases.
Future generations of phytoplankton from this experiment may become more tolerant to temperature changes. This piece of knowledge is so important to determine the future of phytoplankton in our oceans.
References:
- Boyd, 5P. et al. Marine Phytoplankton Temperature versus Growth Responses from Polar to Tropical Waters — Outcome of a Scientific Community-Wide Study.https://journals.plos.org/plosone/article /metrics?id=10.1371/journal.pone.0063091#cited Header (2013).
- Thomas, M. et al. A Global Pattern of Thermal Adaptation in Marine Phytoplankton. https://science.sciencemag.org/content/338/6110/ 1085.full (2012).
