From the edge of the continental shelf, the great ocean depths, whose main characteristic is the almost total absence of sunlight. One of the most important levels in this classification is the bathyal zone, which is located among the 200 and 3.000 meters deepThis region gives way to the abyssal plain, which exceeds 3.000 meters, and the hadal zone, where the deepest ocean trenches on the planet are located.
Characteristics of the bathyal zone
The bathyal zone is an extreme environment marked by environmental factors that challenge marine life. Its main characteristics include:
- Absence of sunlight: The penetration of light is minimal, which prevents the photosynthesis and conditions the adaptations of the organisms that inhabit this area.
- Cold and constant temperatures: At these depths, the water temperature ranges between 2 and 4 degrees Celsius.
- High pressures: The hydrostatic pressure is enormous, increasing approximately one atmosphere for every 10 meters of depth.
- Low oxygen concentration: The great depth and lack of photosynthetic processes limit the amount of oxygen available.
Flora of the bathyal zone
Given the absence of light, photosynthetic vegetation cannot develop in the bathyal zone. However, the base of the food chain In this region it depends on other sources of organic matter, such as:
- Organic debris: Also known as marine snow, are remains of dead organisms and decomposing matter that sink from upper layers.
- Bacterial colonies: Some specialized bacteria can survive in these conditions using processes of chemosynthesis.
Fauna of the bathyal zone
The organisms that inhabit this area have developed extraordinary adaptations to survive in extreme conditions. Among the most representative species are:
Bioluminescent fish
Many fish in the bathyal zone have developed the ability to generate your own light through bioluminescence. This adaptation allows them Attract prey, communicate and even camouflage themselvesExamples of these species include the lantern fish (Myctophidae) And the dragon fish (Stomiidae).
Deep-sea cephalopods
The giant squid and colossal are some of the most enigmatic cephalopods of this region. They have large eyes that allow them to capture the scarce light available and advanced camouflage strategies.
Crustaceans and other invertebrates
The abyssopelagic crustaceans They have adapted to low temperatures and food shortages. Among them are the ostracods, small crustaceans that feed on suspended particles.
Sharks and predators of the bathyal zone
In this ecosystem there are also some sharks adapted to the depths, such as the cigar shark (isistius brasiliensis) And the Pacific sleeper (Somniosus pacificus), species that have developed particular hunting strategies.
Ecological importance of the bathyal zone
Although often overlooked, the bathyal zone plays a crucial role in the balance of the marine ecosystem. It functions as a carbon sink and is home to species that contribute to biological stability of the ocean.
As explorations of the deep advance, we continue to discover new species and fascinating phenomena in the bathyal zone. Understanding its biodiversity is not only key for marine biology, but also for the development of strategies for the conservation and sustainable use of ocean resources.