Potential Impacts of Deep-Sea Mining on Earth's Carbon Cycling Processes Investigated
The seas, often referred to as the "lungs of the Earth," are responsible for producing at least half of the oxygen we breathe. This vital process is primarily carried out by microscopic photosynthetic organisms called phytoplankton, which dwell primarily in the upper 200 meters of the ocean [1][2][5][8]. Some species, such as the bacteria Prochlorococcus, contribute up to 20% of the total oxygen in the biosphere, surpassing even tropical rainforests [1][2].
The Ocean's Crucial Role in Oxygen Production and Climate Control
Phytoplankton thrive in the sunlit portion of the ocean, where they convert carbon dioxide into oxygen, thereby sustaining marine life and significantly contributing to Earth's atmosphere [2][5]. In addition to oxygen production, the ocean serves as the biggest active carbon sink, taking in approximately 30% of human-released CO2 emissions and storing vast amounts of carbon in deep-sea sediments [7][8].
Current Challenges Facing Phytoplankton and Ocean Health
Despite their indispensable role, phytoplankton populations are subjected to severe stress from various human-induced factors:
- Microplastics and Debris: Microplastics and larger debris disrupt the growth of phytoplankton, altering light penetration and releasing toxic substances into the water [4].
- Fukushima Radiation: Concerns have arisen concerning the impacts on marine microorganisms, including phytoplankton, due to radioactive contaminants released into the Pacific Ocean following the 2011 Fukushima nuclear disaster. However, ongoing research is being conducted to understand these impacts [3].
- Ocean Acidification: Increased CO2 absorption leads to decreased ocean pH, which affects phytoplankton physiology and reproduction, as well as disrupting marine food webs [4].
- Rising Waters and Decreased Oxygen Levels: Ocean temperatures on the rise reduce oxygen solubility and disrupt circulation, resulting in the expansion of "oxygen minimum zones" where marine life struggles to survive [6].
The Potential Worsening Effects of Deep-Sea Mining
Mining the ocean floor for minerals like polymetallic nodules puts fragile seafloor ecosystems, and the microbial communities and marine biodiversity essential for oxygen production and nutrient cycling, at risk. Problems caused by this mining include:
- Blockage of Sunlight: Mining activities can increase water turbidity and block sunlight, potentially smothering phytoplankton and other organisms.
- Disruption of Microbial Processes: The processes critical for carbon sequestration and oxygen generation are jeopardized by disturbance from mining equipment.
- Release of Stored Carbon: The release of stored carbon from sediments due to mining activities could potentially increase greenhouse gas emissions.
- Slow Recovery: The recovery of deep-sea ecosystems following disturbance can take decades or even centuries.
Risks to Earth's "Lungs"
Given that the ocean provides about half of the planet's oxygen, any significant disruption to phytoplankton or oceanic microbial life could decrease oxygen production and destabilize the climate system. Oxygen levels in certain ocean regions have already dropped by over 15%, and "dead zones" have been expanding due to eutrophication and warming waters [1][6].
Conclusion
Deep-sea mining represents a significant risk to the ocean's capacity to function as Earth's lungs. Combined with existing stressors from pollution, radiation, acidification, and climate change, mining could drive marine ecosystems past a tipping point, potentially compromising oxygen supply, biodiversity, and global climate regulation.
Preserving these vital ocean systems is essential not only for marine life but for the survival of humanity itself.
Sources: [1] NOAA Ocean Service [2] Woods Hole Oceanographic Institution [5] EarthSky [6] Yale Environment 360 [7] Woods Hole Oceanographic Institution [8] UN Climate Change [9] Deep Sea Conservation Coalition (paraphrased from general knowledge)
- The survival of phytoplankton, crucial for oxygen production and climate control, is threatened by several factors, including microplastics, Fukushima radiation, ocean acidification, and rising waters with decreased oxygen levels [4][6].
- The science behind environmental-science reveals that the ocean serves as the biggest active carbon sink, absorbing approximately 30% of human-released CO2 emissions, but deep-sea mining poses a significant risk to this process by potentially disrupting microbial processes, releasing stored carbon, and slowing recovery times [4][7].
- Finance and energy industries should consider the environmental repercussions of deep-sea mining and climate-change, as the survival of the phytoplankton and the ocean's capacity to function as Earth's lungs is essential for humanity's survival, and any disruption could destabilize the climate system [6].
