Question

krill are small shrimp - like creatures that live in the southern oceans around antarctica. they are part of the zooplankton. they play an important role in the carbon cycle. krill consume up to 12 billion tons of carbon from the earths atmosphere each year. the model below illustrates the role of krill in the carbon cycle. carbon cycling in antarctica image of carbon - cycle diagram with labels: co₂, phytoplankton carbon uptake, krill, migration to deeper waters, fecal pellets dropping to ocean floor and remaining for many years. 3. based on the model, explain how rapid growth in the krill population would affect the cycling of carbon between the atmosphere and biosphere. 4. a carbon sink is anything that absorbs more carbon from the environment than it releases. which process carried out by krill results in the accumulation and storage of carbon for a period of time? (1) photosynthesis in the atmosphere releases carbon to the atmosphere. (2) respiration in the geosphere releases carbon wastes into the atmosphere. (3) elimination of wastes in the hydrosphere stores carbon on the ocean floor. (4) acidification in the biosphere stores carbon in the bodies of organisms.

Explanation:

1. If there is rapid growth in the krill population, more phytoplankton will be consumed by krill. This means less carbon will be taken up by phytoplankton from the atmosphere through photosynthesis. Also, more krill will produce more fecal pellets that drop to the ocean - floor, sequestering more carbon there for a long - time, reducing the amount of carbon in the atmosphere - biosphere cycling.
2. Krill eliminate wastes in the hydrosphere. When their fecal pellets drop to the ocean floor and remain for many years, this stores carbon on the ocean floor. So, the elimination of wastes in the hydrosphere by krill results in carbon accumulation and storage.

Answer:

1. Rapid krill population growth would reduce phytoplankton - mediated carbon uptake from the atmosphere and increase carbon sequestration on the ocean floor, altering the carbon cycling between the atmosphere and biosphere.
2. (3) Elimination of wastes in the hydrosphere stores carbon on the ocean floor.