Tag: ecology and ecosystem

Abiotic factors are the non living part of ecosystem. This can be distinguished into organic and inorganic. Organic include proteins, methane, carbohydrates etc., whereas inorganic includes iron, magnesium, oxygen, nitrogen etc.

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. The fundamental source of energy in almost all ecosystems is radiant energy from the sun. The autotrophs processes the light energy and use the energy stored within the simple carbohydrates to produce the more complex organic compounds. The flow of energy through the ecosystem drives the movement of nutrients within the ecosystem. Decomposers play a key role in many of these cycles, returning nutrients to the soil, water, or air, where they can be used again by the biotic constituents of the ecosystem.

A species whose presence and role within an ecosystem has a disproportionate effect on other organisms within the system. A keystone species is often a dominant predator whose removal allows a prey population to explode and often decreases overall diversity. It includes the American alligators, beavers, bees, elephants, gopher tortoises, grizzly bears, hummingbirds, ivory tree corals, jaguars, mountain lions, mycorrhizal fungi, Pacific salmon and prairie dogs. Thus, Mycorrhiza is a keystone species.

The biosphere is the world of living organisms together with soil layers (land or lithosphere), water (hydrosphere) and air (atmosphere) on the earth surface. Hence, it consists of 4 parts as land, water, air and living organisms. Of which  land, water and air are abiotic or non-living components and living organisms are biotic or living components. 
Producers are one of the type of biotic component, which produce their own food material from simple inorganic substances like $CO _2$ and water in presence of sunlight. E.g., Plants.
Consumers are one of the type of biotic component, which consume food prepared by producers. E.g., Human being, animals.
Decomposers are one of the type of biotic component, which derive their food material from dead, decaying matter. Eg. Bacteria, fungi.
Hence, option A, B and C are incorrect. 
Air is a abiotic or non-living type of component of biosphere. Therefore, option D is correct. 

• Ecosystem is the phenomenon that includes the occurrence and distribution of organisms in the ecosystem and the interaction of species with the environment. 
• It includes abiotic factors such as air, water, soil and biotic factors such as humans, animals, microorganisms. Community includes more that one type of species interacting with each other in a population. 
• The biosphere is the part of the earth in which life exists.

The study of the ecosystem is called "ecology'. The scientists who study the ecosystem are called "ecologists."

The abiotic and biotic components and their interaction with each other combines to form a ecosystem. The biotic components means the living organisms and the abiotic components means the non living factors present in the environment. So, the correct option is A.

An ecosystem is a biological community of interacting organisms and their physical environment. A town is a human-made settlement, not a natural ecosystem.

The biosphere is the area around the earth that consists of living beings along with the non-living matter around them.