https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF S28-EnvironmentEcologyPart-1 S29-EnvironmentEcologyPart-2 S30-EnvironmentEcologyPart-3 S31-EnvironmentEcologyPart-4 S32-EnvironmentEcologyPart-5 S33-EnvironmentEcologyPart-6 Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF Part - 1 Environment & Ecology Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF Topics To Be Discussed I. Ecology II. Ecosystem III. Functions of Ecosystems A. Energy Flow B. Nutrient Cycles C. Ecological Succession D. Homeostasis Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF What is Environment? ➢ The environment may be defined as the surroundings or conditions in which an organism lives or operates. ➢ Every living organism is constantly interacting with its environment comprised of air, light, water, land or substratum and the various kinds of living organisms. ➢ The environment broadly includes living and non-living components. ➢ All organisms depend on their environment for survival. Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF I. Ecology Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF What is Ecology? ➢ Ecology is defined "as a scientific study of the relationship of the living organisms with each other and with their environment." ➢ The term ecology was first coined in 1869 by the German biologist Ernst Haeckel. ➢ It has been derived from two Greek words, ‘oikos’, meaning home or estate and ‘logos’ meaning study. ➢ The emphasis is on relationships between organisms and the components of the environment namely non-living and living. 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Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF Levels of Ecological Organisation ➢ Hence, Ecology not only deals with the study of the relationship of individual organisms with their environment, but also with the study of populations, communities, ecosystems, biomes, and biosphere as a whole. ➢ Individual (organism) is a living being that has the ability to act or function independently. ➢ A population is a group of individuals usually of the same species, occupying a defined area during a specific timeframe. ➢ Communities are usually named after the dominant species. A community is not fixed or rigid, as it changes with time. Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF Organism Individual; basic unit of study. A group of organisms consisting of a number of different populations but Population same species that live in defined area and interact with each other. A group of organisms consisting of a Community number of different species that live in an area and interact with each other. A communities of organisms and Ecosystem their physical environment, interacting as an ecological unit. A large community unit, characterized by a Biome major vegetation type and associated fauna, found in a specific climatic region is a biome. 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Hydrosphere (Water) BIOSPHERE Atmosphere Lithosphere (Air) (Land) Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF Biome ➢ It is the ‘Terrestrial part’ of the biosphere which can be divided into enormous regions called biomes. ➢ Biomes are characterized by climate, vegetation, animal life, and general soil type. ➢ For example, Tundra, Taiga, Desert, etc. ➢ No two biomes are alike, i.e, all biomes are unique in nature. ➢ The most important climatic factors determining biomes are the following two: 1. Temperature 2. Precipitation Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF What is Species? ➢ A species is defined as; “a group of similar populations of organisms whose members are capable of interbreeding, and to produce fertile offspring (children)”. ➢ For example, human, tiger, lion, lotus, rose, dog, etc. ➢ Every species has a scientific name, understood by people of all over the world. ➢ For example, humans belong to the species of Homo sapiens. ➢ Every species has its own set of genetic characteristics that makes the species unique and different from other species. Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF ➢ However, variations are produced as a result of chance mutation among the species. ➢ And competition and natural selection determine as to which variation will succeed and survive. ➢ Those variations that enable a species to survive in the struggle for existence are encouraged and promoted. ➢ Therefore, those offspring which are suited to their immediate environment have a better chance of surviving, reaching reproductive age and passing on the suitable adaptations to their progeny. ➢ Hence, adaptation and diversity of the species is the result of evolution. Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF Habitat ➢ Habitat is the physical environment in which an organism lives. ➢ Each organism has particular requirements for its survival and lives where the environment provides for those needs. ➢ The human gut is the habitat of a tapeworm and the rotting log a habitat of a fungus. ➢ A habitat may support many different species having similar requirements. ➢ For example, a single ocean habitat may support a whale, a sea-horse, seal, phytoplankton, and many other kinds of organisms. Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF Structural Components of a Habitat VestibulumFood congue SpaceVestibulum congue HABITAT VestibulumWater congue Shelter/ Vestibulum congue Cover Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF Ecological Niche ➢ The term niche means the sum of all the activities and relationships of a species by which it uses the resources in its habitat for its survival and reproduction. ➢ In nature, many species occupy the same habitat but they perform different functions. ➢ The functional characteristics of a species in its habitat are referred to as “niche” in that common habitat. ➢ Habitat of a species is like its ‘address’ (i.e. where it lives) whereas niche can be thought of as its “profession” (i.e. activities and responses specific to the species). Website - https://upscpdf.com findfind on on telegram telegram @unacademyplusvideos @unacademyplusvideos https://t.me/UPSC_PDF Website - https://upscpdf.com https://t.me/UPSC_PDF ➢ A niche is unique for a species while many species share the habitat. ➢ No two species in a habitat can have the same niche. ➢ This is because if two species occupy the same niche they will compete with one another until one is displaced. ➢ For example, a large number of different species of insects may be pests of the same plant but they can co-exist as they feed on different parts of the same plant. ➢ The most important resources in the niches of animals are food and shelter while in the case of plants, they are moisture and nutrients (phosphorus and nitrogen). Website - https://upscpdf.com findfind on on telegram