The Environment is our basic life support system which provides the air for breathing, the water for drinking, the food for eating and the land for a living. It is collectively portrayed all the external forces and conditions, which influences the life, nature, growth and maturity of living organism, whereas ‘Ecology’ is the scientific analysis and study of interactions among organisms and their environment.
1. The Environment is self sustained by nature and its factors (biotic, climatic, edaphic, etc.) act collectively and simultaneously in Holocoenotic way, so that the action of one may be qualified by the others, any imbalances therein cause a chain reaction.
2. All the environmental factors are broadly classified as biotic and abiotic. Biotic factor includes all living organisms, their food, behaviour and interactions and are adjusted with evolutionary adoption to the abiotic factors, includes all non-living physical elements like, soil, water, climate, pollution etc.
3. Ecology is the most important aspect of the environment that studies the organisms and all its functional processes within their habitable zone. The word 'ecology' was coined by German Scientist Ernst Haeckel in 1866.
4. An ecosystem is a region with a specific and recognisable landscape form, such as a forest, grassland, desert, wetland or coastal area. They are open systems and the losses of material from one ecosystem eventually become gain for another in the biosphere. This flow connects the ecosystems with a tendency to overlap and the overlapping zone between two adjacent ecosystems is called ecotone.
5. Every ecosystem sustains on six principles, Speciation, Diversity, Habitat, Adaptation, Interdependence and Evolution. An ecosystem has four fundamental functions, i.e., Productivity, Decomposition, Energy flow and Nutrient cycle.
6. The transfer of energy in an ecosystem, called food chain that is always vertically upward and generally follow the 10% mobilisation rule through a series of organisms broadly classified as producers/autotrophs, consumers/ heteorotrophs and Decomposers.
7. Producers are generally green plants or other simple creatures, which form complex organic compounds from simple physical abiotic components that is provided as nutrient and energy for next trophic level, consumers / heteorotrophs and finally decomposed by decomposers like bacteria, fungi etc and drawn back to the physical environment again completing the nutrient cycle.
8. Food chains are normally of three types three types, i.e., Grazing food chain; where nutritions flow from green plants to decomposers through consumers, Deteritus food chain; where dead and decay organisms are primary sources and sustaining micro-organism for predators finally decomposers and another unique one is Parasitic food chain; where unlike the above two, nutrition flows without consumption of the source level i.e., smaller organisms live on bigger organism without harming them (bed bug, leech. creepers, etc.) Sometimes the relationship between host and parasite is symbiotic.
9. A complex food chain includes many inter-related trophic levels, is called a food web in which food or energy relationship between organisms of different trophic levels follows a definite pattern and graphically represented as ecological pyramid.
10. Ecological Pyramids are of three types: Pyramid of number, Pyramid of biomass and Pyramid of energy. Pyramid of energy is always upright where as Pyramid of biomass and Pyramid of number may be inverted or irregular in some cases like Open Ocean etc.
11. Biological communities develop and establish in an area in a series of stages responding to its environment. The change in species composition and community structure and function over time is called Ecological Succession. Succession is a continuous and sequential process starts with primary succession as moss, grass; etc on bare rocks/soil finally culminates in an equilibrium community, called the climax community.
12. Tropical evergreen forest and coral reef ecosystems are the most productive and most diverse ecosystems on Earth. Biomes are the world's major communities, classified according to the predominant vegetation and characterised by adaptation of organism to that particular environment. Five major biomes are aquatic, deserts, forests, grasslands and tundra biomes.
13. Some species are more adaptive and have special behavioural pattern to a specific climate such as, Xerophytes are adapted to drought and dry conditions, halophytes are plants growing in saline condition and ephemerals shorten their life cycle according to the climate, i.e., tundra moss, mountain flowers etc. Desert animals avoid hottest and driest season by becoming in-active, known as Aestivation and same in cold regions known as Hibernation.