Energy Flow and Nutrient Cycling in the Epipelagic Zone of the Ocean
Introduction: “Energy Flow’’ is an environmental process that describes the flow of energy through a food chain and attempts to ascertain the relative importance of various individual component species and feeding relationships within a particular ecosystem.
“Energy” itself is defined as the ability to do work: All living plants and animals expend energy in their environment. All three laws of thermodynamics apply, especially the first: “Energy can neither be created or destroyed, but merely converted from one form to another”. In any ecosystem, energy is lost to the surroundings.
A “Nutrient” is a food or any nourishing substance assimilated by an organism and required for growth, repair, and metabolism. Plants derive nutrients from the physical environment e.g. air, water, and sediment, whereas animals from ingested food. [3]
The term “Nutrient Cycle” describes the exchange and movement of inorganic and organic matter back into the production of living matter.
I will examine the Energy Flow and Nutrient Cycle in one ecosystem: The Epipelagic Zone of the Ocean. An ocean is a body of saline water that composes much of the planet’s hydrosphere. The ocean contains thousands of known species. A typical ocean is divided into several zones, with the Epipelagic (sunlight) Zone spreading from the surface to a depth of 200m. As one descends deeper into the ocean beyond this zone, light intensity decreases significantly, oxygen levels fluctuate, and the temperature drops -making it more difficult for organisms to survive and flourish. Energy Flow The Epipelagic zone is bathed with sunlight during the daytime and the temperature varies from 40oC to 4oC. There is a constant diffusion of oxygen gas, carbon-dioxide gas, and Nitrogen gas from the atmosphere into the water. This creates an environment for organisms to thrive. The sun is ultimately the source of all energy on Earth. Plant life that contains the pigment chlorophyll use carbon-dioxide and Water to convert this solar energy into chemical energy in the form of carbohydrates, and oxygen necessary for aerobic respiration: These are Primary Producers, and include the following species; Green Algae (Chlorophyte), Free-Floating Algae/Seaweed, Red Algae (Rhodophyta), Brown Algae (e.g Kelp), [photosynthetic] Phytoplankton (e.g Diatoms), and plants such as sea-grasses. These are the first link in the food-chain, and therefore many animals live in this zone. Examples of such animals are: Rays, Sharks, Jellyfish, Sea turtles, Seals, Coral, and Zooplankton. Fish, and mammals such as whales, from lower depths will also come to this zone to feed on both fish and plant-life. The phytoplankton is one of the main producers, and they’re fed on by the zooplankton. On average, a phenomenon known as the “10% Rule” applies i.e as one goes up the food pyramid, 10% of the energy is transferred to the next level. 90% of the energy is expended by organisms in day-to-day activities and the generation of heat. Therefore 10,000,000 phytoplankton would only sustain 1,000,000 zooplankton (primary consumers and herbivores). These in turn would only be able to support 100,000 Secondary Consumers e.g carnivores such as Sardines, and squid. Following this pattern, only a 1000 Tertiary consumers would be supported at the next level e.g. Dolphins, Seals, Pelicans. This in turn would only be able to support 100 Quaternary Consumers e.g. Killer Whales, Great-White Sharks, Tuna. As we can see, there is a direct relationship between the transfer of energy from one trophic-level to the next, and the population …show more content…
The producers, using the process of photosynthesis, will have converted the Carbon-Dioxide into new organic compounds such as glucose. Plants and animals use glucose in the process of respiration to produce energy, while excreting Carbon-Dioxide, and Water. This Carbon-Dioxide that is excreted by the plants and animals can be used again by photosynthetic plants. Fish/Animals eat these plants and assimilate the Carbon into their bio-chemical structure. In this way, Carbon is passed along the food-chain. Eventually, the animals at the top of the food-chain die, and as they fall towards the sea-bed, they’re scavenged upon, and decomposed by bacteria. Overtime, this Carbon may appear as a fossil fuel, and thus may be returned to the atmosphere as CO2, which eventually dissolves into the water -and the cycle begins
Introduction: “Energy Flow’’ is an environmental process that describes the flow of energy through a food chain and attempts to ascertain the relative importance of various individual component species and feeding relationships within a particular ecosystem.
“Energy” itself is defined as the ability to do work: All living plants and animals expend energy in their environment. All three laws of thermodynamics apply, especially the first: “Energy can neither be created or destroyed, but merely converted from one form to another”. In any ecosystem, energy is lost to the surroundings.
A “Nutrient” is a food or any nourishing substance assimilated by an organism and required for growth, repair, and metabolism. Plants derive nutrients from the physical environment e.g. air, water, and sediment, whereas animals from ingested food. [3]
The term “Nutrient Cycle” describes the exchange and movement of inorganic and organic matter back into the production of living matter.
I will examine the Energy Flow and Nutrient Cycle in one ecosystem: The Epipelagic Zone of the Ocean. An ocean is a body of saline water that composes much of the planet’s hydrosphere. The ocean contains thousands of known species. A typical ocean is divided into several zones, with the Epipelagic (sunlight) Zone spreading from the surface to a depth of 200m. As one descends deeper into the ocean beyond this zone, light intensity decreases significantly, oxygen levels fluctuate, and the temperature drops -making it more difficult for organisms to survive and flourish. Energy Flow The Epipelagic zone is bathed with sunlight during the daytime and the temperature varies from 40oC to 4oC. There is a constant diffusion of oxygen gas, carbon-dioxide gas, and Nitrogen gas from the atmosphere into the water. This creates an environment for organisms to thrive. The sun is ultimately the source of all energy on Earth. Plant life that contains the pigment chlorophyll use carbon-dioxide and Water to convert this solar energy into chemical energy in the form of carbohydrates, and oxygen necessary for aerobic respiration: These are Primary Producers, and include the following species; Green Algae (Chlorophyte), Free-Floating Algae/Seaweed, Red Algae (Rhodophyta), Brown Algae (e.g Kelp), [photosynthetic] Phytoplankton (e.g Diatoms), and plants such as sea-grasses. These are the first link in the food-chain, and therefore many animals live in this zone. Examples of such animals are: Rays, Sharks, Jellyfish, Sea turtles, Seals, Coral, and Zooplankton. Fish, and mammals such as whales, from lower depths will also come to this zone to feed on both fish and plant-life. The phytoplankton is one of the main producers, and they’re fed on by the zooplankton. On average, a phenomenon known as the “10% Rule” applies i.e as one goes up the food pyramid, 10% of the energy is transferred to the next level. 90% of the energy is expended by organisms in day-to-day activities and the generation of heat. Therefore 10,000,000 phytoplankton would only sustain 1,000,000 zooplankton (primary consumers and herbivores). These in turn would only be able to support 100,000 Secondary Consumers e.g carnivores such as Sardines, and squid. Following this pattern, only a 1000 Tertiary consumers would be supported at the next level e.g. Dolphins, Seals, Pelicans. This in turn would only be able to support 100 Quaternary Consumers e.g. Killer Whales, Great-White Sharks, Tuna. As we can see, there is a direct relationship between the transfer of energy from one trophic-level to the next, and the population …show more content…
The producers, using the process of photosynthesis, will have converted the Carbon-Dioxide into new organic compounds such as glucose. Plants and animals use glucose in the process of respiration to produce energy, while excreting Carbon-Dioxide, and Water. This Carbon-Dioxide that is excreted by the plants and animals can be used again by photosynthetic plants. Fish/Animals eat these plants and assimilate the Carbon into their bio-chemical structure. In this way, Carbon is passed along the food-chain. Eventually, the animals at the top of the food-chain die, and as they fall towards the sea-bed, they’re scavenged upon, and decomposed by bacteria. Overtime, this Carbon may appear as a fossil fuel, and thus may be returned to the atmosphere as CO2, which eventually dissolves into the water -and the cycle begins