Life in coral reefs are much like life in sunken ships
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There are three categories of organisms in every ecosystem: producers, consumers, and decomposers. Producers, often referred to as primary producers, consist of organisms that are capable of making their own food and are consequently always photosynthetic (and in some cases chemosynthetic). Consumers are placed higher on the trophic pyramid than producers, and they can be herbivorous, omnivorous or carnivorous. Primary consumers are herbivorous, whereas secondary consumers prey on herbivores and tertiary consumers eat other carnivores. Decomposers are responsible for breaking down dead and decaying plant and animal matter into components that are once again usable for growth by producers. None of these three categories of organisms can exist without the others in order to complete the cycle of production, consumption, and decomposition.
Producers
Primary producers, or autotrophs, make up the base of all food chains. Autotrophs are capable of synthesizing complex organic compounds such as glucose from a combination of simple inorganic molecules and light energy in a process known as photosynthesis. Other much less common autotrophs (some bacteria) derive their energy from the oxidation of inorganic compounds such as hydrogen sulfide, ferrous iron, and ammonium and are referred to as chemoautotrophs. A good example of marine chemoautotrophs are the bacteria that inhabit deep sea hydrothermal vents; they are the primary producers in this hostile environment and are able to convert heat, methane, and sulfur into energy through a process called chemosynthesis and can survive in water temperatures of 750 °F (400 °C) and a pH of 2.8.
Consumers
- primary consumers
Phytoplankton and other single-celled primary producers are eaten by primary consumers. Primary consumers are herbivorous and they encompass a wide range of marine creatures including zooplankton, invertebrate larvae,benthic grazers (e.g. bivalves, gastropods, tunicates, sponges, polychaete and feather duster worms), some corals, sea urchins, some crabs, green sea turtles, and herbivorous fish. Zooplankton are undoubtedly the most abundant primary consumers in the water column; copepods, amphipods, ciliates, and tintinnids are all common types of zooplankton. Due to the large community of primary consumers on coral reefs, phytoplankton levels in coral reef waters can be 15-65% lower than in adjacent open ocean waters. Benthic grazers and some coral species feed by filtering phytoplankton out of the water while other vertebrate and invertebrate grazers eat algae and seaweed; many species of parrotfish, surgeonfish and blennies have a diet that consists entirely of coralline, filamentous, and calciferous algae.
Decomposers (and Detrivores)
Decomposers serve an extremely important function in all ecosystems; they break down dead biological matter and waste products and convert them into usable energy while returning important materials to the environment. The main decomposers in coral reefs are bacteria; these bacteria play an integral part in the nitrogen cycle whereby ammonia (NH4) is converted into nitrite (NO2) by bacteria in the genus Nitrosomonas, after which nitrite is then converted into nitrate (NO3) by bacteria in the genus Nitrobacter. The ultimate result is that levels of toxic wastes are kept very low and that waste products are converted into components that are available to producers in a readily-usable form. Decomposers are particularly important in coral reef environments considering the heavy bio-load. Detrivores, or scavengers, play a similar role in recycling dead or waste material; sea cucumbers and some species of snails, crabs and bristle worms consume dead organisms and/or decaying plant and animal matter (detritus). (Coral Reef Ecology)
Producers
Primary producers, or autotrophs, make up the base of all food chains. Autotrophs are capable of synthesizing complex organic compounds such as glucose from a combination of simple inorganic molecules and light energy in a process known as photosynthesis. Other much less common autotrophs (some bacteria) derive their energy from the oxidation of inorganic compounds such as hydrogen sulfide, ferrous iron, and ammonium and are referred to as chemoautotrophs. A good example of marine chemoautotrophs are the bacteria that inhabit deep sea hydrothermal vents; they are the primary producers in this hostile environment and are able to convert heat, methane, and sulfur into energy through a process called chemosynthesis and can survive in water temperatures of 750 °F (400 °C) and a pH of 2.8.
Consumers
- primary consumers
Phytoplankton and other single-celled primary producers are eaten by primary consumers. Primary consumers are herbivorous and they encompass a wide range of marine creatures including zooplankton, invertebrate larvae,benthic grazers (e.g. bivalves, gastropods, tunicates, sponges, polychaete and feather duster worms), some corals, sea urchins, some crabs, green sea turtles, and herbivorous fish. Zooplankton are undoubtedly the most abundant primary consumers in the water column; copepods, amphipods, ciliates, and tintinnids are all common types of zooplankton. Due to the large community of primary consumers on coral reefs, phytoplankton levels in coral reef waters can be 15-65% lower than in adjacent open ocean waters. Benthic grazers and some coral species feed by filtering phytoplankton out of the water while other vertebrate and invertebrate grazers eat algae and seaweed; many species of parrotfish, surgeonfish and blennies have a diet that consists entirely of coralline, filamentous, and calciferous algae.
Decomposers (and Detrivores)
Decomposers serve an extremely important function in all ecosystems; they break down dead biological matter and waste products and convert them into usable energy while returning important materials to the environment. The main decomposers in coral reefs are bacteria; these bacteria play an integral part in the nitrogen cycle whereby ammonia (NH4) is converted into nitrite (NO2) by bacteria in the genus Nitrosomonas, after which nitrite is then converted into nitrate (NO3) by bacteria in the genus Nitrobacter. The ultimate result is that levels of toxic wastes are kept very low and that waste products are converted into components that are available to producers in a readily-usable form. Decomposers are particularly important in coral reef environments considering the heavy bio-load. Detrivores, or scavengers, play a similar role in recycling dead or waste material; sea cucumbers and some species of snails, crabs and bristle worms consume dead organisms and/or decaying plant and animal matter (detritus). (Coral Reef Ecology)