Explain which three marine habitats would have the least access to phytoplankton, and why.
1) Deep sea: The deep sea habitat is characterized by very low levels of sunlight, extreme pressures, and cold temperatures. These conditions make it difficult for sunlight to penetrate the water column, thus limiting the growth of phytoplankton. Additionally, deep-sea currents are often too weak to transport nutrient-rich water, further limiting phytoplankton growth.
2) Arctic and Antarctic regions: These regions have long periods of darkness during winter months, which limits the amount of sunlight available for photosynthesis. During the summer months, ice coverage can also limit phytoplankton growth by blocking sunlight. The cold temperature of the water slows down the metabolism of phytoplankton further, which reduces their reproduction rate.
3) Open ocean: Parts of the open ocean that are far from nutrient-rich continental shelves have a low concentration of phytoplankton. The open ocean experiences a phenomenon called nutrient limitation, where the water contains low concentrations of essential nutrients all-year-round; this limits the productivity of phytoplankton and, in turn, the food web. Additionally, the open ocean is subject to nutrient recycling processes, where sinking organic matter is degraded by bacteria, and the nutrients are recycled. This means the nutrients required by phytoplankton often sink to deeper levels where they are less accessible.
Three marine habitats that would have the least access to phytoplankton are:
1. Deep Ocean: The deep ocean is characterized by extreme depths, where sunlight penetration is minimal. Phytoplankton depends on sunlight for photosynthesis, and without sufficient light, they cannot thrive. Therefore, the deep ocean has limited access to sunlight, leading to a lack of phytoplankton.
2. Polar Regions: The Arctic and Antarctic regions are known for their cold temperatures and extensive ice coverage. These icy conditions make it difficult for phytoplankton to grow and survive. Ice cover limits sunlight penetration, hindering photosynthesis, and reducing the availability of phytoplankton in polar waters.
3. Upwelling Zones: Upwelling zones occur where cold, nutrient-rich deep waters rise to the surface. While these areas can have high levels of nutrients, they often have low levels of phytoplankton. This is due to the upwelling process bringing nutrient-rich but typically low phytoplankton abundance waters from the deep, which takes time for the phytoplankton to multiply and eventually reach sufficient levels. As a result, upwelling zones have relatively limited access to phytoplankton.
In summary, the deep ocean, polar regions, and upwelling zones have the least access to phytoplankton due to factors such as limited sunlight penetration, ice coverage, and the time required for phytoplankton populations to grow in specific upwelling conditions.