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Describe the energy flow in ecosystems

      

Describe the energy flow in ecosystems

  

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Francis
Energy, initially fixed from solar radiation into a chemical form by green plants, moves into herbivores are a result of their feeding upon plants, and then moves on into carnivores as the herbivores themselves are consumed. Scavengers, detritus feeders and decomposers exploit the dead tissues and the leftovers of plant material and herbivores. Thus all organisms in any community can be classified in term of their feeding behaviour. A series of complex food webs are usually formed relating each species to many others. Solar energy forms main input into the ecosystem. Variations in the distribution of solar radiation (energy moving at the or near the speed of light) with latitude are an important factor in the location of major climatic belts, which in turn impose broad geographical limits on the distribution of biota over the biosphere. The efficiency of the photosynthesis process varies from species to species but is generally quite low. Only about 10% of the solar energy is effectively converted, and because of losses in maintenance and respiration, this efficiency usually falls to as low as 1% or 2%. Of total energy arriving at a site, only about 40% is available to plants. The remainder cannot be absorbed by chlorophyll because it is of the wrong wavelength.
The environment is characterised by interactions between physical, or abiotic components such as (atmosphere, geology, and soil) and living, biotic components (the organisms). Within the biotic part of the environment, a fundamental distinction is made between plants and animals. Thus biologists distinguish between these organisms that make their own food from simple inorganic material (autotrophic organisms) and those that require complex organic molecules already constructed from them (heterotrophic
organisms).
• Heterotrophs are unable to construct their own organic molecules from a solely inorganic source an as such, must feed on autotrophs in order to survive.
• The autotrophs are also known as primary producers, while the heterotrophs are consumers.

The distinction according to feeding habit is an important one in ecology, as it allows for a structural classification of hierarchical structure within ecosystems. In this hierarchy, the key role is played by those organisms, which contain chlorophyll (green plants) and are therefore able to make organic compounds from simple inorganic molecules by utilising solar energy to drive the reaction. This process is called photosynthesis or primary productivity. Green plants with their ability to fix solar energy, form the basis of the ecosystem hierarchy, they are eaten by other organisms that live above them in
the classification, (consumers), these in turn eaten yet by more organisms higher up in this hierarchical system. This type of hierarchy is known as the food chain (Figure 7). The various components of the food chain (food web) are linked together functionally to produce a dynamic and interacting system, the ecosystem, which is the building block of the biosphere.
francis1897 answered the question on October 5, 2022 at 13:10

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