Page 1

What are the components of an Ecosystem? Class 12 Biology


What are the components of an Ecosystem? Class 12 Biology

The term Ecosystem was proposed by A.G. Tansley in 1935. The ecosystem is defined as the integration of all the living and nonliving factors of the environment�. An ecosystem is also defined as a community made up of living organisms and nonliving components such as air, water and mineral soil, all interacting as a system. Thus, an ecosystem has two basic components (i) Abiotic components (non-living components) (ii) Biotic components (living components) The relationship between the abiotic components and the biotic components of the ecosystem is termed ‘holocoenosis’.


What are the components of an Ecosystem? Class 12 Biology


What are the components of an Ecosystem? Class 12 Biology

ABIOTIC COMPONENTS The abiotic components of an ecosystem include the water, the air, the temperature and the rocks and minerals that make up the soil. The biotic components of the ecosystem both live on and interact with the abiotic components. Abiotic factors are classified asClimatic factors include the climatic regime of an area with physical factors in the environment such as light, atmospheric temperature, wind, humidity, etc. Edaphic factors, which relate to the composition and structure of the soil like its chemical and physical properties – like the soil type, soil profile, organic matter, minerals, soil water, and soil organisms. Inorganic substances like water, carbon, sulfur, nitrogen, phosphorus and so on. Organic substances like proteins, lipids, carbohydrates, humic substances etc. BIOTIC COMPONENTS It consists of the living parts of the environment, including the association of a lot of interrelated populations that belong to different species inhabiting a common environment. There is a population of the animal community, the plant community, and the microbial community. The biotic community is divided into autotrophs, heterotrophs, and saprotrophs.


What are the components of an Ecosystem? Class 12 Biology


What are the components of an Ecosystem? Class 12 Biology

• Autotrophs (from Greek: auto – self, trophos – feeder) are called producers, transducers or converters, as well. Those are photosynthetic plants; they normally bear chlorophyll, which synthesizes a high-energy complex organic compound (or food) from the inorganic raw materials utilizing the sunlight, by the process of photosynthesis. Autotrophs form the core of all biotic systems. In terrestrial ecosystems, autotrophs are usually rooted plants. In the aquatic ecosystems, the floating plants referred to as phytoplankton and the shallow water rooted plants – macrophytes – are the main producers. • Heterotrophs (from Greek: heteros – other; trophs – feeder) are the consumers. The consumers are also referred to as phagotrophs (phago – to swallow or ingest) while macro consumers are normally herbivores and carnivores. Herbivores are called First order or primary consumers, for they feed directly on green plants. For example, Terrestrial ecosystem consumers are cattle, deer, grasshopper, rabbit, etc. Aquatic ecosystem consumers are protozoans, crustaceans, etc. Carnivores are animals that prey or feed on other animals. They are called Second order consumers or Primary carnivores like animals that feed on herbivorous animals. For example, fox, frog, smaller fishes, predatory birds, snakes, etc. Third order consumers or Secondary carnivores are the animals that feed on primary carnivores. For example, wolf, owl, peacock, etc. Some larger carnivores (quaternary consumers or tertiary carnivores) prey on Secondary carnivores. For example, the lion, the tiger, etc. They are not eaten by any other animal. The larger carnivores which cannot be preyed on further are also called the top carnivores. •


What are the components of an Ecosystem? Class 12 Biology


What are the components of an Ecosystem? Class 12 Biology

• Saprotrophs (from Greek again: sapros – rotten; trophies – feeder) are called the reducers or decomposers. They break the complex organic compounds in a dead matter (dead plants and animals). Decomposers don’t ingest the food. Instead, they secrete a digestive enzyme into the dead, decaying plant or animal remains and digest this organic material. The enzymes act on the complex organic compounds in the dead matter. Decomposers absorb a bit of the decomposition products to provide themselves with nourishment. The remaining substance is added as minerals. The released minerals are utilized or reused as nutrients by plants – the producers. • • For School courses, Professional courses, and Skill development courses, Class 12 Biology Online Classes kindly visit www.takshilalearning.com • For more topics of Class 12th Science, • Follow us on Blogarama • Follow us on Pinterest • Follow us on Youtube • Follow us on Facebook • Biology notes for class 12: Call us: 8800999280/8800999284

What are the components of an Ecosystem? Class 12 Biology  

An ecosystem is also defined as a community made up of living organisms and nonliving components such as air, water and mineral soil, all i...

What are the components of an Ecosystem? Class 12 Biology  

An ecosystem is also defined as a community made up of living organisms and nonliving components such as air, water and mineral soil, all i...

Advertisement