Buffed Corals?

As a Stuyvesant student, you’ve probably heard about Mr. Citron’s undying love for coral reefs or even seen his coral reef aquarium in school. Unfortunately, these creatures, ecosystems, and habitats face exceptional threats due to climate change caused by human activities. As a result, coral populations are declining alarmingly, and scientists are tirelessly seeking innovative solutions to revive them. One groundbreaking approach has been the introduction of coral gyms.

Coral reefs are marine ecosystems formed primarily by coral polyps. These tiny creatures are related to anemones and jellyfish, and they create the reef's framework through a process known as coral reef building. They first mass reproduce, creating colonies of coral polyps, which consist of genetically identical individual polyps. Polyps cement together to form structures known as coral skeletons that provide habitats for numerous marine species. Coral skeletons form through calcification, a process where coral polyps secrete calcium carbonate to form a hard exoskeleton for protection.. This process repeats over several generations of polyps, resulting in the growth of coral colonies over time. Coral polyps rely on a symbiotic relationship with photosynthetic algae called zooxanthellae, which live within their tissues. These algae provide the corals (corals are often used to refer to the entire colonial organism, including the polyps, skeleton, and associated symbiotic algae) with sugars—a source of energy—through photosynthesis and other essential nutrients, while the corals offer the algae protection and access to sunlight. The polyps use the energy to support their metabolic activities, including growth, reproduction, and tissue repair. In addition to producing sugars, zooxanthellae release organic nitrogen and phosphorus compounds as metabolic waste products. The corals absorb these nutrients to support various physiological processes, such as protein synthesis, DNA replication, and cell division, which are all processes needed for production of their skeletons. Corals struggle to maintain their health, fitness, and vibrant colors without an adequate supply of these essential nutrients.

Other than looking beautiful and providing habitat for marine life, coral reefs also serve essential ecological functions. Coral reefs serve as natural barriers that protect coastlines from erosion, storm surges, and wave action. They also play a role in the global carbon cycle by sequestering carbon dioxide from the atmosphere to incorporate it into their calcium carbonate skeletons. This process helps mitigate climate change by reducing the amount of carbon dioxide in the atmosphere and thus lowering greenhouse gas levels. Coral reefs support thriving fisheries that provide sustenance and livelihoods for millions worldwide. Fish caught from coral reefs constitute a significant portion of the global seafood supply and are a crucial source of protein for coastal communities in many developing countries. 

However, coral reefs also require specific environmental conditions to thrive and maintain their complex ecosystems. For example, warm water, usually between 20°C and 29°C, is essential for the growth and survival of the coral polyps and the zooxanthellae (symbiotic algae) living within their tissues. The increase in global mean temperature worldwide negatively affects coral reefs. When water temperatures rise above the optimal range for coral reef health, corals can experience thermal stress. Thermal stress disrupts the symbiotic relationship between corals and zooxanthellae, leading to coral bleaching. Prolonged exposure to elevated temperatures can result in widespread coral bleaching events and mass coral mortality, devastating coral reef ecosystems.

Furthermore, climate change causes ocean acidification. Seawater absorbs excess atmospheric carbon dioxide (CO2). In doing so, the CO2 reacts with seawater to form carbonic acid. This chemical reaction between CO2 and seawater increases the concentration of hydrogen ions, leading to a decrease in pH and a shift towards greater acidity. This affects coral reefs as they rely on calcification to build their calcium carbonate skeletons. Ocean acidification reduces the availability of carbonate ions in seawater, as the increase in hydrogen ions from the ionization of carbonic acid can react with carbonate ions present in seawater, forming bicarbonate ions. Thus, coral reefs and other marine organisms cannot readily complete the process of calcification as they cannot use bicarbonate for shells, so they die off.

Currently, the Environmental Protection Agency (EPA) plays a crucial role in safeguarding coral reefs by implementing programs under the Clean Water Act. These programs focus on supporting initiatives to monitor and evaluate the health of coral reefs across the United States. The EPA is constantly developing tools and strategies aimed at helping these ecosystems adapt to changing environmental conditions by collaborating with other federal agencies, state governments, and territories to coordinate conservation efforts effectively. For instance, the EPA actively participates in the U.S. Coral Reef Task Force, which facilitates interagency cooperation in coral reef conservation, working with the U.S. Army Corps of Engineers to minimize impacts to coral reefs from discharges of material.

Other initiatives, such as coral nurseries or gyms, are used to combat the fast deterioration in corals. Coral nurseries involve the cultivation of coral fragments in controlled environments, such as land-based facilities or underwater structures. Here, scientists study coral growth, reproduction, responses to environmental stressors, and gather other viable information. Once the corals have grown to a specific size, they are transported to degraded reef areas to help restore the surrounding coral population. Coral gyms pioneer methods to bolster coral strength in the lab. For example, leader of the Coral Program at the National Oceanic and Atmopsheric Administration’s Atlantic Oceanographic and Meteorological Laboratory Enochs and his team aimed to uncover which coral species and genotypes possess the resilience needed to combat worsening climate change through DNA analysis and stimulus of various environmental conditions in their lab to determine the "fittest" corals. They recognized that reefs with a history of temperature variability tend to fare better in the face of climate change. Such coral reefs are found around the eastern Pacific as they are exposed to the Pacific Equatorial Countercurrent and seasonal upwelling events. Indeed, reefs in this region, such as those in the Galápagos Islands and Panama, have shown resilience to temperature stress and bleaching events. His research is being used to introduce such Pacific corals into other degraded environments worldwide. 

Though t scientists are researching diligently to minimize the harm climate change has on the coral reef ecosystem, the devastation that coral reefs are experiencing echoes the mass destruction that humankind has inflicted onto the environment. Protecting coral reefs are important, if not for our selfish needs of pharmaceutical research and tourist attraction, but for the sake of protecting a complex society that has thrived for centuries.