Ecosystem Test - 6

Net primary production is the rate at which all the plants in an ecosystem produce net useful chemical energy; it is equal to the difference between the rate at which the plants in an ecosystem produce useful chemical energy (GPP) and the rate at which they use some of that energy during respiration.

So respiration is the metabolic process which causes a reduction in gross primary production.

Due to changing conditions of sunlight and temperature, the productivity increases from polar areas to tropic area. At polar region sunlight and temperature is low as move from poles to tropical regions.

An ecological pyramid is a graphical representation designed to show the biomass or bio productivity at each trophic level in a given ecosystem.

An ecological pyramid cannot exhibit same species belonging to two or more trophic levels in a food web. So, saprophytes are not included in ecological pyramids.

The marine biome is the biggest biome in the world. It covers about 70% of the earth. It includes five main oceans: the Pacific, Atlantic, Indian, Arctic, and Southern, as well as many smaller Gulfs and Bays.

Marine biomes remain almost same for all geographical location. It is affected by temperature, salinity and types of sea floor or stratification.

At each trophic level only ten percent of energy is transferred from one trophic level to next trophic level from producer to consumers.

20000 × (10/100)³ = 20J

So, only 20J of energy is available to tertiary consumers.

Agro ecosystems do not have diversity as single or a few crops are grown together in artificial agro ecosytem. Biodiversity is not available in artificial ecosystem.

The abyssal zone or abyssopelagic is a layer of the pelagic zone of the ocean. "Abyss" derives from the Greek word ἄβυσσος, meaning bottomless.

At depths of 3,000 to 6,000 metres, this zone remains in perpetual darkness and never receives daylight. These regions are also characterised by continuous cold and lack of nutrients.

The abyssal zone has temperatures around 2°C to 3°C (35 °F to 37 °F) through the large majority of its mass.

Hydrothermal vents present in deep ocean lacks any autotrophic organisms as producer but have some chemotrophic bacteria are able to produce food called chemoautotrophs.

Coral reefs in aquatic ecosystem hold the same position as held by tropical rainforest in terrestrial ecosystem. Both coral reefs and tropical rainforest have large numbers of diversity.

In a food chain, number of organisms reduce from producer to carnivores at each trophic levels. So, the number of carnivores will be less than the prouder which is less than 10 million.