The environment is the sum total of all conditions and influences that affect the development and life of all organisms on earth. The importance of Environment and Ecology has become highly useful resources to crack different competitive examinations. The basic Concepts related to the Environment and Ecology are discussed below:
1. Atmosphere: The gaseous envelop surrounding the earth.
2. Air Pollution: Various gaseous pollutants from natural and man-made sources enter the atmosphere and have adverse effects on the normal properties of air. This leads to air pollution, which is harmful for life and environment.
3. Air Pollutants: Gases and particles which cause air pollution are called air pollutants.
4. Air Quality: It is the degree to which the air in a particular place is pollution-free.
5. Aquifer: A highly permeable and porous layer of sediment or rock containing water.
6. Anthropogenic: It is related to the study of the origin and development of human beings.
7. Abiotic Component: Non-living component in an ecosystem.
8. Afforestation: Planting of trees in an area to provide a forest cover.
9. Appiko Movement: Movement against the destruction of forest.
10. Artificial Environment: The objects of our surroundings made by man.
11. Antibiotics: It is a chemical substance derivable from a mould or bacterium that can kill microorganisms and cure bacterial infections.
12. Autotroph: It is a biological term which is a combination of two words- auto which means self and troph means "nourishing". Autotrophic organisms synthesize their own food from simple organic substances.
13. Age-structure: Percentage of men and women in the young, adult and old age group in the population.
14. Acid Rain: Rain water containing mixtures of acids (nitric, hydrochloric and sulfuric acid) from polluted air is known as acid rain. It damages lakes, forests and marble sculptures.
15. Auto Ecology: It is a study of individual organism or species in relation to environment.
16. Bagasse: The crushed cane after extraction of juice.
17. Biogeo Chemical Cycle: Pathway of circulation of elements within an ecosystem.
18. Biodiversity: It refers to the variability among living organisms from all sources, including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species, and of ecosystems.
19. Biogas: Gas (energy resource) originated from animal dung. It is useful fuel in rural areas.
20. Biological Environment: All living beings present in our surrounding are included in biological environment.
21. Biome: A broad region-based ecosystem with distinct climate, soil, flora and fauna.
22. Biomass: Standing crop (living matter) of living organisms in terms of weight, present at any given time in the environment.
23. Biosphere: Composite environment consisting earth and atmosphere in which Organisms live.
24. Biotic Component: Living component (i.e., plants, animals, and microbes) in an ecosystem.
25. Bioaccumulation: Accumulation of non-biodegradable substances in the body (e.g., lead, mercury, DDT etc.) through food chain.
26. Carbon Cycle: Natural cycle based on exchange of carbon-dioxide among Atmosphere, Biosphere and Ocean.
27. Carcinogen: Chemicals promoting cancer e.g., benzo-α-pyrene, arsenic, DDT etc.
28. Carrying Capacity: Maximum population size that a given system can support over a given period of time.
29. Chlorofluorocarbons (CFC): Used as solvent, refrigerant, fire retardant etc. Responsible for ozone hole and greenhouse effect.
30. Community: Population of various species living and interacting in a given area.
31. Carnivorous: Animals that feeds on other animals.
32. Compost: A nutrient rich soil produced by decomposition of organic matter under aerobic conditions.
33. Commensalism: Association of different species in which one of the organisms is benefitted but the other organism is neither benefitted nor harmed under normal condition.
34. Conservation: Planned management of the surroundings of man to prevent its exploitation or destruction.
35. Environmental dumping: It refers to the practice of transfrontier shipment of waste from one country to another.
36. Decibel: Unit for measurement of intensity of noise.
37. Deciduous: The trees that becomes leafless for a certain period of the year.
38. Decomposer: The organisms depend on dead remains of producer’s aril consumer for their food.
39. Biodegradable Pollutants: Those pollutants which can be broken down into simpler, harmless, substances in nature in due course of time.
40. Demography: The study of human population in all respect.
41. Deforestation: Destruction of forest cover. Desertification: The process leading to desert formation. Detritus: Dead organic matter mainly of fallen leaves as life litter in forest.
42. Detrivores: The microbes decomposing detritus.
43. Domestic Wastes: The materials that are discarded by human beings in their daily activities.
44. Drainage: The removal of surface or subsurface water from an area by natural or artificial means.
45. Drought: Abnormal conditions appear-in an environment due to low rainfall or absence of rainfall for a long time in a particular area.
46. DDT: Pesticide useful in agriculture and eradication of malaria.
47. Doubling Time: Period during which population doubles itself. It is about 100 years in developed countries and 40 years in India.
48. Dependency Ratio: Ratio of people 65+ (above 65) and 15 (under 15) to the rest of the population.
49. Evergreen Plant: Plants having green leaves throughout the year. Exploitation: The relationship in which one organism is benefited by the direct utilization to other.
50. Ecology: Study of interactions of living organisms with their biotic and abiotic environments.
51. Ecosystem: A biological community and its physical environment exchanging matter and energy.
52. Environment: Something that environs i.e., encircles all our surroundings—the natural world in which we live — the living and non-living objects around us in our day-today living.
53. Environmental Studies: The studies of the quality of environment and all aspects of human environment, their degradation etc. comprise environmental studies.
54. Eutrophication: Over nourishment of waterbodies due to excessive nitrates and phosphates received through runoff— it is harmful for the waterbodies.
55. Environmental Impact Assessment (EIA): A systematic analysis of the effects of a major development project on environment.
56. Extinction: Loss of species on earth as natural or manmade process.
57. EX-situ Conservation: Conservation of endangered species away from their natural habitat.
58. Earthquake: The shaking and trembling of earth due to movement inside the lithosphere that could be tectonic or volcanic.
59. Energy: Ability to do work. Environment The physical, chemical and biotic conditions surrounding an organism (P.N. Arora et al.).
60. Environmental Biology: The science that deals with inter-relationship between organisms and their environment.
61. Fauna: Species content of animals present in an area. Fertilizers: The inorganic materials which can supply plant nutrients in available form.
62. Fertility Rate: The number of live birth per unit time per unit number of fertile female.
63. Flora: A species content of plants present in an area. Flood: Submerges of the vast area of land with water.
64. Fly Ash: Finely divided particles of ash produced from thermal electric plant
65. Food Chain: Method of transferring of food elements among environment, producers, consumers and decomposer. Fodder: Green feed of cattle.
66. Forest: Plant community predominantly of trees, often with an extensive undergrowth of shade tolerant shrubs and herbs usually with closed company.
67. Grazing: Eating away of unharvested herbs as forage by animals.
68. Ground Water: Water contained underneath the surface of the earth.
69. Growth Rate: The difference between natality and mortality in a population.
70. Gasohol: Mixture of gasoline and alcohol is known as gasohol, used as a fuel in Brazil for running cars and buses.
71. GNP (Gross National Product): An index of a country’s economic status based on consumerism i.e., commodities purchased per year, consumer durables and financial status of consumer.
72. Greenhouse Effect (Global Warming): Rise in temperature of the earth’s surface due to increase in the levels of greenhouse gases viz., carbon dioxide, methane etc. The latter trap heat from the earth’s surface and returns it thereby raising the earth’s surface temperature. This phenomenon is similar to trapping of heat in glass covered green house (used for growth of vegetables and flowers during winter) and hence called greenhouse effect.
73. Greenhouse Gases: Gases such as carbon dioxide, methane, water vapour etc. which absorb earth’s infra-red radiation, return it to the earth’s surface thereby raising the temperature (global warming).
74. Groundwater: Water held in aquifers 50% below the earth’s surface. This is the major source (0.66%) for freshwater.
70. Health: It is a state of complete physical, mental and social wellbeing and not merely an absence of disease or infirmity and ability to lead a socially and economically productive life (WHO 1948).
71. Heredity: Genetically desired traits and qualities obtained from parents and ancestors. Herbivores: The animal feed on producer (i.e., green plant).
72. Heterotrophs: Animal and non-green plants not capable of producing food. Hydrological Cycle: The process of continuous circulation of water between atmosphere and the earth's surface.
73. Heterotroph: Organism that can’t synthesize its own food and derives its nourishment by feeding on other.
74. Humus: A dark amorphous substance that is partially degraded and serves as a major source of nutrients to plants.
75. Hurricanes: Cyclonic storms with heavy rains and wind at speed exceeding 120 km/per hour.
76. Incineration: The process of burning solid wastes in an inclinator at high temperature.
77. Insecticide: Chemical used for controlling insects.
78. Infant Mortality: Number of infants born per 1000 who die before their first birthday.
79. Life Expectancy: Average number of years a new-born baby is expected to survive.
80. Lithosphere: Outer shell of the earth’s crust made of the mantle of rocks. It includes the soil which covers the rock’s crust in many places.
81. Magma: Molten rock below the earth’s surface.
82. Monoculture: Cultivation of a single crop of tree.
83. Natural Gas: Underground deposits of gases containing mainly methane and small amounts of propane and butane. It is a cleaner fuel than fossil fuel as it produces less carbon dioxide on burning.
84. Natural Hazards: Hazards from natural sources (earthquake, volcanic eruption etc.) which destroy or damage human lives, houses etc.
85. Neutron: Nuclear particle with zero charge and mass, (relative to it).
86. Nitrogen Cycle: Continuous exchange of nitrogen within the ecosystem: air-soil-water.
87. Nitrogen Fixation: Conversion of atmospheric nitrogen gas into ammonia by nitrogen-fixing bacteria/cyanobacteria.
88. Nuclear Fission: Splitting of nucleus (uranium/ plutonium) into two or more fragments with release of tremendous amount of energy. This is the source of nuclear power (electricity generation).
89. PAN (Peroxyacyl Nitrate): A toxic product of photochemical smog reactions.
90. Particulate Matter: Solid particles or ligand droplets suspended in air. Examples are smog particles from combustion of fossil fuels.
91. Photosynthesis: Synthesis of food (carbohydrates) by green plants in the presence of sunlight using carbon dioxide from air and water from soil.
92. Phytoplankton: Small plants like algae, bacteria found floating on the surface of water. Photovoltaic Cell: Solar cell that converts solar energy into electricity.
93. Population Explosion: Excessive growth of population as in developing countries, to a size that exceeds the carrying capacity.
94. Primary Pollutants: Gaseous and particulate pollutants discharged directly into the atmosphere by automobile exhaust emissions. The gases thus discharged are carbon monoxide, nitrogen oxides, sulphur dioxide, and hydrocarbons.
95. Residence Time: Length of time for which a chemical or molecule stays in the environment. For example, the residence time of CFC (chlorofluorocarbon) molecule in the stratosphere is 100 years.
96. Sanitary Landfill: Waste disposal site on land in which solid waste is spread with fresh layer of clay.
97. Secondary Pollutant: Harmful pollutants generated from primary pollutants air, for example, sulphonic acid is a secondary pollutant, produced by the primary pollutant sulphur dioxide by reaction with water vapour in air.
98. Sustainable Development: Improvement in quality of life over a long-term without degrading the environment or compromising the needs of future generations.
99. Tectonic Plates: Huge blocks of earth’s crust which slide along slowly.
100. Transpiration: Loss of water from plant surfaces.
101. Troposphere: The bottom region of the atmosphere at an altitude of 0-11 km. It contains 70 per cent of air masses which are always in motion. Here temperature decreases with increasing altitude.
102. Stratosphere: This region is above the troposphere at an altitude of 11-50 km above the earth’s surface. Here ozone acts as a protective shield against ultraviolet radiation from space and thus protects life on earth.
103. Urbanization: Increasing population in cities by migration from villages and other states. India has a huge urban population (about 300 million).
104. Waterlogging: Saturation of soil with irrigation water or excessive rain whereby water table rises close to surface.
105. Watershed: Land area from which water drains under gravity to a common drainage channel.
106. Wetlands: Ecosystems with stagnant water pool and having rooted vegetation.