aquatic ecosystem
Quick Summary
An aquatic ecosystem is a body of water viewed as a system where living organisms interact with their environment. This includes freshwater environments like ponds and lakes, which are characterized by their water's physical and chemical properties, such as temperature, light penetration, and nutrient levels. These properties influence the distribution of life, from microscopic plankton to larger organisms.123
Inland aquatic ecosystems typically have three main trophic levels: producers (like algae), consumers (animals), and decomposers (bacteria and fungi). Energy flows through these levels, while essential elements cycle between biotic and abiotic components. Human activities, such as pollution and nutrient runoff, can severely impact these ecosystems, leading to issues like eutrophication, which is the excessive enrichment of water bodies with nutrients.34
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respiratory systemThe gases in the environment…as an air breather, an aquatic animal may find it necessary to pass across the respiratory surfaces a relatively larger volume of the external medium. Moreover, the diffusion rate of oxygen is much lower in water than in air. The problem is further compounded by the higher density (1,000 times…
Read More…as an air breather, an aquatic animal may find it necessary to pass across the respiratory surfaces a relatively larger volume of the external medium. Moreover, the diffusion rate of oxygen is much lower in water than in air. The problem is further compounded by the higher density (1,000 times…
Read More- respiratory systemReptiles
In aquatic reptiles diving occurs during these pauses, which may last an hour or more in some turtles and aquatic snakes. Even terrestrial reptiles show intermittent periods of breathing and breath holding. The metabolic rate of most reptiles is one-fifth to one-tenth that of birds or…
Read MoreIn aquatic reptiles diving occurs during these pauses, which may last an hour or more in some turtles and aquatic snakes. Even terrestrial reptiles show intermittent periods of breathing and breath holding. The metabolic rate of most reptiles is one-fifth to one-tenth that of birds or…
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marine ecosystemMarine waters cover two-thirds of the surface of the Earth. In some places the ocean is deeper than Mount Everest is high; for example, the Mariana Trench and the Tonga Trench in the western part of the Pacific Ocean reach depths in excess of 10,000 metres…
Read MoreMarine waters cover two-thirds of the surface of the Earth. In some places the ocean is deeper than Mount Everest is high; for example, the Mariana Trench and the Tonga Trench in the western part of the Pacific Ocean reach depths in excess of 10,000 metres…
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inland water ecosystem…of living organisms in free water on continental landmasses.
Read More…of living organisms in free water on continental landmasses.
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crustaceanEcologyCrustaceans play many roles in aquatic ecosystems. The planktonic forms—such as the copepod Calanus and the krill Euphausia—graze on the microscopic plants floating in the sea and in turn are eaten by fishes, seabirds, and whales. Benthic (bottom-dwelling) crustaceans are a food source for fish, and some whales feed extensively…
Read MoreCrustaceans play many roles in aquatic ecosystems. The planktonic forms—such as the copepod Calanus and the krill Euphausia—graze on the microscopic plants floating in the sea and in turn are eaten by fishes, seabirds, and whales. Benthic (bottom-dwelling) crustaceans are a food source for fish, and some whales feed extensively…
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echinodermRole in natureEchinoderms are efficient scavengers of decaying matter on the seafloor, and they prey upon a variety of small organisms, thereby helping to regulate their numbers. When present in large numbers, sea urchins can devastate sea-grass beds in the tropics, adversely affecting the…
Read MoreEchinoderms are efficient scavengers of decaying matter on the seafloor, and they prey upon a variety of small organisms, thereby helping to regulate their numbers. When present in large numbers, sea urchins can devastate sea-grass beds in the tropics, adversely affecting the…
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microbiologyMicrobiology of water supplies, wastewater, and other aquatic environmentsThe microorganisms inhabiting aquatic environments are collectively referred to as plankton; phytoplankton refers to the photosynthetic microbes (primarily algae), whereas protozoa, and other small animals, are zooplankton. Phytoplankton is responsible for converting solar energy into chemical energy—the components of plankton cells that serve as food for
Read MoreThe microorganisms inhabiting aquatic environments are collectively referred to as plankton; phytoplankton refers to the photosynthetic microbes (primarily algae), whereas protozoa, and other small animals, are zooplankton. Phytoplankton is responsible for converting solar energy into chemical energy—the components of plankton cells that serve as food for
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perciformFeeding behaviour…of great importance within the ecological food chains. The diverse adaptations for feeding are partly responsible for the success of this abundant order. Many of the colourful perciforms that occur around coral reefs are herbivorous fishes, the food of which consists mainly of plankton, algae on corals, and other reef…
Read More…of great importance within the ecological food chains. The diverse adaptations for feeding are partly responsible for the success of this abundant order. Many of the colourful perciforms that occur around coral reefs are herbivorous fishes, the food of which consists mainly of plankton, algae on corals, and other reef…
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