Plankton: The Underrated Superheroes of Our Oceans
No one can deny the majesty of a blue whale, the intelligence of a dolphin, or the grace of a manta ray. Yet, we often overlook the smallest marine life forms that are the driving force behind all this marine grandeur – the humble plankton.
Plankton, derived from the Greek term ‘planktos’ meaning wanderer or drifter, (1) encompasses a diverse collection of organisms that live in the water column of oceans, seas, and water bodies and cannot swim against the current. They are found across the world’s oceans, ranging from surface waters to the deep sea. Despite their tiny size, their role in maintaining marine ecosystems and our planet as a whole cannot be understated.
Plankton classification
Plankton is classified into two main groups: phytoplankton and zooplankton.
Phytoplankton, made up of microscopic plants like algae, forms the base of the marine food chain. They use sunlight to photosynthesize, much like land-based plants, providing their own food plus oxygen for all ocean life and, significantly, the planet.
Zooplankton are animal planktons. They are usually microscopic, but some like the jellyfish are larger. Zooplankton consume phytoplankton as their main food source, and in turn, they become the primary food source for larger marine animals. From here, the web of life continues, eventually leading to the largest marine creatures.
Planktons vs. Marine Ecosystem
Estimates suggest that phytoplankton produces about half of the world’s oxygen through photosynthesis each year. The carbon dioxide absorbed during this process contributes to mitigating the impact of global warming, labeling plankton, particularly phytoplankton, as powerful allies in our fight against climate change.
It’s not just about carbon capture and oxygen production, though. Plankton also plays a significant role in the planet’s water cycles. Their presence influences how sunlight is reflected and absorbed, impacting ocean temperatures, weather formation, and cloud cover. Thus, indirectly, they regulate precipitation and weather patterns, affecting our everyday lives, our agriculture, and our water sources.
Plankton holds immense bio-diversity and plays a crucial role in marine biodiversity. Different species of plankton indicate different water quality levels, serving as bio-indicators of aquatic health.
Plankton’s Thermometers
Monitoring and studying worldwide plankton populations is crucial for better understanding our planet’s health and climate change effects. Plankton’s sensitivity to temperature variations makes them ideal thermometers for our oceans. The plankton distribution change can also help predict climatic variations that might result in natural disasters such as hurricanes. Researchers employ advanced tools like Continuous Plankton Recorders (CPRs) to monitor plankton population.
Tiny Heroes, Big Threats
Unfortunately, our tiny heroes are facing an existential threat due to human-triggered changes in marine ecosystems. Activities like offshore drilling and marine pollution due to oil spills and plastic waste have led to declining plankton populations.
Changes in ocean temperatures due to global warming cause loss of habitats for some plankton species, leading to changes in plankton distribution and the marine food chain. Furthermore, ocean acidification, another consequence of climate change and increased CO2 levels, directly affects shell-building plankton species, stifling their growth.
Conservation Measures
The marine scientific community worldwide is focused on studying the impact of environmental stressors on plankton populations and devising conservation strategies. The establishment of marine protected areas is one such strategy to provide habitats where plankton can thrive.
Many global projects aim to monitor, protect, and study plankton like the National Oceanic and Atmospheric Administration’s (NOAA) Phytoplankton Monitoring Network in the United States and several projects under the European Marine Observation and Data Network. Consumer choices can also contribute to protecting plankton and their habitats, by reducing, reusing, and recycling, especially plastics, and supporting organizations dedicated to conserving our oceans.
Conclusion:
Plankton is the lifeblood of our oceans, and thus our planet. These tiny, often invisible, creatures are fundamental to maintaining life as we know it. Next time you take a deep breath of fresh air, spare a thought for the microscopic marine warriors that made it possible. The health of these tiny organisms is a clear indicator of our ocean’s and thus our planet’s health. We need to do everything we can to protect them.
