Ecosystem Ecology emphasizes the movement of energy and nutrients among the biotic and abiotic components of ecosystems. It examines physical and biological structures and how these characteristics interact with each other. A major focus of ecosystem ecology is on functional processes, ecological mechanisms that maintain the structure and services produced by ecosystems. These include production of biomass, decomposition and tropic interactions. In short ecosystem ecology studies the interdependent functional processes behind food chain and food web and how all the applied to cases such as increased effects of atmospheric co₂ on coral reefs and fishes or to understand the effects of increased pesticides application on the pests and birds preying on them.
Ecosystems
Having done with basic concepts we will return to the ecosystems. As said earlier, ecosystem is a fundamental functional unit characterized by total assemblage of biotic community and abiotic components and their mutual interactions in a given space time unit.
Ecosystems can be classified as following:
(i) On the basis of habitats:
(a) Terrestrial – Upland or mountain; Lowland; Warm Desert and Cold Desert.
(b) Aquatic – Fresh Water; Marine.
(ii) On the basis of human intervention:
(a) Natural ecosystems e.g. tall grass or Amazon rainforest ecosystem.
(b) Artificial or cultivated ecosystems e.g. rice field ecosystem.
Components of the Ecosystem
(1) Abiotic Components – the non living factors such as minerals, soil, air, water, light, etc.
(2) Biotic Components – the living factors. These include plants, animals, microbes, etc. They live within abiotic components. They are of two types:
(i) Autotrophs: Those plants which synthesize their food themselves either through photosynthesis (photographs) or chemosynthesis (chemothrophs). They are the primary producers of ecosystem.
(ii) Heterotrophy: These are those organisms which obtain their food by eating plants or other animals or their products. They are the consumers. They depend upon producers, plants, directly or indirectly. Heterotrophy can be further divided as follows:
(a) Herbivores – they obtain their food only from living plants.
(b) Carnivores- they obtain their food only from animals.
(c) Omnivores- They obtains their food from both plants and animals.
(d) Detrivores – They obtain their nutrients by consuming detritus i.e. decomposing plant and animal parts. The terms detrivores and decomposers are often used interchangeably. But there is a difference while they both get nutrition from dead organic matter; the detrivores actually eat organic matter (like earthworms eating their way through soil) and decomposers secrets enzymes to digest the organic matter and then absorb the resulting molecules like bacteria or fungi do.
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