Benthic predators

From our figure of 10 g dry wt-m-2 for benthic fauna we attributed 7.5 g dry wt-m-2 to the herbivores, leaving a biomass of 2.5 g dry wt-m-2 for the predators. With a calorific value of 5 kcal-g-1 dry wt the energy content of this biomass is 12.5 kcal-m-2.

These animals feed on the benthic herbivores and may also eat dead bodies of fish. From our assumed annual production of 37.5 kcal-m-2-yr-1 of benthic herbivores, 12kcal-m-2-yr-1 has been eaten by demersal fish, leaving 25.5 kcal-m-2-yr-1 available for benthic predators. There is also the balance of production of demersal fish after the removal of 0.2 kcal-m-2-yr-1 by fisheries,

1.e. 2.4 - 0.2 = 2.2 kcal-m-2-yr-1, making a total of about 27.7kcal-m-2-yr-1 for benthic predators. If they consume all this food energy and have a GCE of 0.15, the annual production would amount to about 4 kcal-m-2-yr-1, the respiratory loss about 24 kcal • m-2 • yr-1 and the annual yield a little under 32 per cent of stock weight.

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Renewable Energy 101

Renewable Energy 101

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable. The usage of renewable energy sources is very important when considering the sustainability of the existing energy usage of the world. While there is currently an abundance of non-renewable energy sources, such as nuclear fuels, these energy sources are depleting. In addition to being a non-renewable supply, the non-renewable energy sources release emissions into the air, which has an adverse effect on the environment.

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