Environment 2025 PDF

 TABLE OF CONTENTS SR.No. CHAPTER Page No. 1. Evolution 01 2. Ecology 03 3. Functions Of An Ecosystem 12 4. Forest Vegetation In India 22 5....

 TABLE OF CONTENTS SR.No. CHAPTER Page No. 1. Evolution 01 2. Ecology 03 3. Functions Of An Ecosystem 12 4. Forest Vegetation In India 22 5. Aquatic Ecosystem 28 6. Biodiversity 41 7. Biodiversity Conservation 49 8. Species Specific Initiative’s 78 9. Sustainable Development 94 10. Environmental Impact Assessment 104 11. Climate Change And Global Warming 107 12. Waste Management 127 13. Pollution And Related Issues 136  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 1 EVOLUTION  ORIGIN OF LIFE The universe is very old – almost 20 billion years old. Huge clusters of galaxies comprise the universe. Galaxies contain stars and clouds of gas and dust. The Big Bang theory attempts to explain to us the origin of universe. 1. It talks of a singular huge explosion unimaginable in physical terms. The universe expanded and hence, the temperature came down. 2. Hydrogen and Helium formed sometime later. The gases condensed under gravitation and formed the galaxies of the present day universe. 3. In the solar system of the milky way galaxy, earth was supposed to have been formed about 4.5 billion years back. 4. There was no atmosphere on early earth. Primitive gases Water vapour, methane, carbondioxide and ammonia released from molten mass covered the surface. 5. The UV rays from the sun brokeup water into Hydrogen and Oxygen and the lighter H2 escaped. 6. Oxygen combined with ammonia and methane to form water, CO2 and others. 7. The ozone layer was formed. As it cooled, the water vapour fell as rain, to fill all the depressions and form oceans. 8. Life appeared 500 million years after the formation of earth, i.e., almost four billion years back.  Theories of origin of life Early Greek thinkers thought units of life called spores -‘Panspermia were transferred to different planets including earth. For a long time it was also believed that life came out of decaying and rotting matter like straw, mud, etc. Louis Pasteur by careful experimentation demonstrated that life comes only from pre-existing life. Oparin of Russia and Haldane of England proposed that the first form of life could have come from pre- existing non-living organic molecules (e.g. RNA, protein, etc.) and that formation of life was preceded by chemical evolution, i.e., formation of diverse organic molecules from inorganic constituents.  Sequence of evolution The first non-cellular forms of life could have originated 3 billion years back. They would have been giant molecules (RNA, Protein Polysaccharides, etc.). These capsules reproduced their molecules perhaps. About 2000 million years ago (mya) the first cellular forms of life appeared on earth. Some of these cells had the ability to release O2. Bacteria → Bacteria with chlorophyll + photosynthesis → O2 → Protista (single-celled) → Fungi (multi- cellular) → Plants → Animal → Ecological evolution. Download Our App Delhi Secrets 1 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY first organisms that invaded land were plants. animals called lobefins evolved into the first amphibians that lived on both land and water. The first mammals were like shrews. Scientist Contribution Anton Van Leeuwenhoek Food Chain How Ecological Gradient Increases From Pole To Alexander Humbolt Equator Ernst Haeckel Termed Ecology Charles Darwin Evolution Arthur G Tensely Ecosystem Valdimir Vernadsky Biosphere Friedrich Ratzel Biogeography Charles Elton Ecological Pyramid Norman Myers Concept Of Hotspot  Download Our App Delhi Secrets 2 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 2 ECOLOGY Definition - Ecology is a subject which studies the interactions among organisms and between the organism and its physical (abiotic) environment. Ecology is basically concerned with four levels of biological organisation – organisms, populations, communities and biomes. term ‘ecology ’ (oekologie or oecologie) was first coined and used by the German biologist, Ernst Haeckel. Ramdeo Misra is revered as the Father of Ecology in India. Ecosystem is a subpart of ecology. It comprises of a biotic factor including all animals, plants, and microorganisms, and an abiotic factor including all non-living physical factors in the environment. main difference between ecology and ecosystem is that ecology is the study of ecosystems whereas ecosystems are units that are formed by the interaction of a community of organisms with the environment. While Environment is the sum total of all conditions and influences that affect the development and life of all organisms on earth. Thus it can be said as one’s surrounding. ECOLOGICAL UNITS : 1. Individual - Organism is an individual living be- ing that has the ability to act or function inde- pendently. It may be plant, animal, bacterium, fungi, etc. It is a body made up of organs, organ- elles, or other parts that work together to carry out on the various processes of life. 2. Population : In nature, we rarely find isolated, single individuals of any species; majority of them live in groups in a well-defined geographical area, share or compete for similar resources, potentially interbreed and thus constitute a population. Examples of a population : Although the term interbreeding implies sexual reproduction, a group of individuals resulting from even asexual reproduction is also generally considered a population for the purpose of ecological studies. All the cormorants in a wetland, rats in an abandoned dwelling, teakwood trees in a forest tract, bacteria in a culture plate and lotus plants in a pond. it is at the population level that natural selection operates to evolve the desired traits. A population has certain attributes whereas, an individual organism does not. An individual may have births and deaths, but a population has birth rates and death rates. In a population these rates refer to per capita births and deaths. Download Our App Delhi Secrets 3 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Another attribute characteristic of a population is sex ratio. An individual is either a male or a female but a population has a sex ratio. A population at any given time is composed of individuals of different ages- age pyramids Population size, technically called population density (designated as N). Population Growth not a static parameter changing with time, depending on various factors including food availability, predation pressure and adverse weather, fluctuates due changes in four basic processes- 1) Natality refers to the number of births during a given period in the population that are added to the initial density. 2) Mortality is the number of deaths in the population during a given period. 3) Immigration is the number of individuals of the same species that have come into the habitat from elsewhere during the time period under consideration. 4) Emigration is the number of individuals of the population who left the habitat and gone elsewhere during the time period under consideration. Populations grow through births and immigration and decline through deaths and emigration. When resources are unlimited, the growth is usually exponential but when resources become progressively limiting, the growth pattern turns logistic. In either case, growth is ultimately limited by the carrying capacity of the environment. The intrinsic rate of natural increase (r) is a measure of the inherent potential of a population to grow. CARRYING CAPACITY : For a given region, carrying capacity is the maximum number of individuals of a given species that an area’s resources can sustain indefinitely without significantly depleting or degrading those resources BIOTIC POTENTIAL : The maximum rate at which a population can increase when resources are unlimited and environmental conditions are ideal. » Each species will have a different biotic potential due to variations in species reproductive span, the frequency of reproduction, litter size, survival rate.  Population Interactions : INTERACTION TYPE COMBINATION EFFECTS EXAMPLES POSITIVE INTERACTION Mutualism (+ ) (+) Both species benefitted Lichen, Mycorrhiza (+ ) (0) One species is benefitted and the orchids, Lianas, cattle egret and Commensalism other species is neither benefitted nor grazing cattle, sea anemone and harmed the clown fish NEGATIVE INTERACTION (+ ) (-) One species benefitted, the other Drosera; Nepenthes prickly species are harmed They keep prey pear cactus & cactus-feeding a Predation populations under control. moth, starfish Pisaster, Monarch butterfly (+ ) (-) One species benefitted, the other Cuscuta, Duranta, Viscum, Brood Parasitism species are harmed. parasitic mode of parasitism in birds- cuckoo (koel) life ensures free lodging and meals Download Our App Delhi Secrets 4 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY (- ) (-) Harmful for both process in which Grassland species, flamingoes the fitness of one species (measured and resident fishes, zooplankton Competition in terms of its ‘r’ the intrinsic rate of increase) is significantly lower in the presence of another species Amensalism (- ) (0) Harmful for one but the other species Peniciflium and Staphylo coccus are unaffected 3. Community : In order to survive, individuals of any one species depend on individuals of different species with which they actively interact in several ways. eg : Animals require plants for food and trees for shelter. Plants require animals for pollination, seed dispersal, and soil microorganism to facilitate nutrient supply. Communities in most instances are named after the dominant plant species. A grassland community is dominated by grasses, though it may contain herbs, shrubs, and trees, along with associated animals of different species. 4. Ecosystem : An ecosystem is defined as a structural and functional unit of biosphere consisting of community of living beings and the physical environment, both interacting and exchanging materials between them. It includes plants, trees, animals, fish, birds, micro-organisms, water, soil, and people. Everything that lives in an ecosystem is dependent on the other species and elements that are also part of that ecological community. Components of Ecosystem : 1. Abiotic Components : are the inorganic and non-living parts of the world. The abiotic part consists of soil, water, air and light energy etc. It also involves chemicals like oxygen, nitrogen etc. and physical processes including volcanoes, earthquakes, floods, forest fires, climates, and weather conditions. 2. Biotic Components- : Biotic components include living organisms comprising plants, animals and microbes and are classified according to their functional attributes into producers and consumers. Primary producers : Autotrophs (self-nourishing)- Primary producers are basically green plants (and certain bacteria and algae). They synthesise carbohydrate from simple inorganic raw materials like carbon dioxide and water in the presence of sunlight by the process of photosynthesis for themselves, and supply indirectly to other non producers. In terrestrial ecosystem, producers are basically herbaceous and woody plants, while in aquatic ecosystem producers are various species of microscopic algae. Consumers : Heterotrophs or phagotrophs- Consumers are incapable of producing their own food (photosynthesis). They depend on organic food derived from plants, animals or both. Consumers can be divided into two broad groups namely micro and macro consumers. (i) Macro consumers - feed on plants or animals or both. Herbivores, Carnivores, Omnivores. (ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) They are bacteria and fungi (Decomposers -microscopic in size) which obtain energy and nutrients by decomposing dead organic substances (detritus) of plant and animal origin. detritus feeders -earthworm and certain soil organisms (such as nematodes, and arthropodsb,beetles, termites dungflies, woodlice millipeds) help in the decomposition of organic matter → detrivores. Download Our App Delhi Secrets 5 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Chemosynthesis : They are autotrophs , some specialized bacteria can can extract inorganic compounds from environment and convert them to organic , found at hydrothermal vent in sea. Scavengers : Decomposers having scavenging habitat ,only eating dead pray without spending energy to kill it. Marine or ocean ecosystem have maximum 7 trophic level. Territorial ecosystem will have 5 trophic level. Only 10% net energy produced at each trophic level an 90% lossed. Energy is not recycled in decomposition but rather is released mostly as heat. 5. Biome : The terrestrial part of the biosphere is divisible into enormous regions called biomes, which are characterized, by climate, vegetation, animal life and general soil type. most important climatic factors are temperature and precipitation. 6. Biosphere : Biosphere is a part of the earth where life can exist. Biosphere represents a highly integrated and interacting zone comprising of atmosphere (air), hydrosphere (water) and lithosphere (land ).  Difference between Ecosystem and Biome : ECOSYSTEM BOIME It is the interaction of abiotic and biotic It is a large area of land with distinct climate and 1. components between each other in a given 1. plant and animal species area. 2. It is a small geographical area 2. It is a large geographical area. It is not much influenced by the climatic factors It is greatly influenced by climatic factors such as 3. 3. like ice, snowfall, temperature etc snow, ice, rainfall, temperature etc. It is a part of biome made of biotic and abiotic It is a larger category of ecological units. It 4. 4. factors contains multiple ecosystems within it. An ecosystem has a less diversity of plants and As a biome is a collection of species it has a great 5. animals species than that of a biome as it is 5. diversity of plant and animal species. smaller in size 6. An ecosystem is not affected by latitude. 6. Latitude has a great influence on a biome. All the animals and organisms of an ecosystem All the animals of a biome may not interact with 7. 7. interact with each other. each other. examples include coral reefs, ponds, Gulf of Some common examples of biomes include 8. 8. Mexico desert, tundra, grasslands, and tropical rain forests  Goods and Services provided by ecosystems include : Provision of food, fuel and fibre. Provision of shelter and building materials. Purification of air and water ,Detoxification and decomposition of wastes. Download Our App Delhi Secrets 6 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Stabilization and moderation of the Earth’s climate. Moderation of floods, droughts, temperature extremes and the forces of wind. Generation and renewal of soil fertility, including nutrient cycling. Pollination of plants, including many crops Control of pests and diseases. Maintenance of genetic resources as key inputs to crop varieties and livestock breeds, medicines, and other products. Cultural and aesthetic benefits.  Classification of Eco-system The ecological principles – 1. natural ecosystem is a fundamental unit of ecological study. 2. ‘sustained life on the earth is a characteristic of ecosystem’. 3. ecosystem functions through the input of mainly solar energy. 4. there is unidirectional flow of energy through various trophic levels in natural ecosystem. 5. the relative loss of energy due to respiration increases with higher trophic levels. 6. the ecosystem productivity and ecological production depend on - (i) the availability of the amount of solar energy to the primary producers (autotrophic green plants) at trophic level one, and (ii) the efficiency of plants to convert solar energy into chemical (food) energy. 7. the natural ecosystem attains its stability through homeostatic mechanism. Ecosystems are capable of maintaining their state of equilibrium. They can regulate their own species structure and functional processes. This capacity of ecosystem of self regulation is known as homeostasis. 8. ecosystem instability and ecological imbalance result when an ecosystem becomes unable to adjust with environmental changes, whether natural or anthropogenic.  Ecotone : is a zone of junction between two or more diverse ecosystems. For e.g. the mangrove forests represent an ecotone between marine and terrestrial ecosystem. Other examples are – grassland, estuary and river bank  Ecocline : Ecocline is a zone of gradual but continuous change from one ecosystem to another when there is no sharp boundary between the two in terms of species composition. Download Our App Delhi Secrets 7 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Characteristics of Ecotone : It may be very narrow or quite wide. It has the conditions intermediate to the adjacent ecosystems. Hence it is a zone of tension. It is linear as it shows progressive increase in species composition of one in coming community and a simultaneous decrease in species of the other out going adjoining community. some organisms which are entirely different from that of the adjoining communities. number of species and the population density of some of the species is much greater in this zone than either community. This is called edge effect.  Niche : A niche is the unique functional role or place of a species in an ecosystem. It is a description of all the biological, physical and chemical factors that a species needs to survive, stay healthy and reproduce. A niche is unique for a species, which means no two species have exact identical niches. Niche plays an important role in conservation of organisms. Types of Niche : Habitat niche – where it lives Food niche – what is eats or decomposes & what species it competes with Reproductive niche – how and when it reproduces. Physical & chemical niche – temperature, land shape, land slope, humidity & other requirement.  Habitat : Another aspect of a species’ niche is its habitat. The habitat is the physical environment in which a species lives and to which it is adapted. A habitat’s features are determined mainly by abiotic factors such as temperature and rainfall. Features of the habitat- space, food, water and cover or shelter 1. ecosystem can be of two basic types 1. Open Ecosystem : When there is a free exchange of energy and matters from outside. Most ecosystems are open. For example, a desert surrounded by farmland - the two different ecosystems will affect one another. 2. Closed Ecosystem : When the ecosystem is isolated from outside. No materials can leave or enter, but only energy from external sources can. Example : Bottle gardens and aquarium ecospheres are partially or fully enclosed glass containers that are self-sustaining closed ecosystems that can be made or purchased. They can include tiny shrimp, algae, gravel, decorative shells, etc. Earth is example of closed ecosystem Download Our App Delhi Secrets 8 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY  TERRESTRIAL ECOSYSTEM : They constitute the interrelations between organisms and the environment on land. They are divisible into many biomes that have varied climate, flora, fauna, soils etc. No two biomes are alike. The climate determines the boundaries of a biome and abundance of plants and animals found in each one of them. The most important climatic factors are temperature and precipitation.  TYPES OF TERRESTRIAL ECOSYSTEMS : TYPE OF TERRESTRIAL BIOME VEGETATION FAUNA Tundra means barren land. Reindeer, arctic fox, wolves, musk-ox, polar Soil is under permafrost. bear, lemming, arctic hare, arctic willow.An- imals have long life hick cuticle and epider- Tundra Biome : Two types The lowest forms like mosses, lichens mal hair or fur- protectc from the cold. of tundra – Arctic and are sparsely found on bare rocks. Alpine (high mountains Insects emerge when snow thaws. Mammals- large body size and small tail above the tree line) and ear to avoid the loss of heat from the Insects have short life cycles which are surface.Reptiles and amphibians are almost completed during the favourable peri- absent. ods. Evergreen coniferous forest with- Siberian tiger, wolverine, lynx, wolf, bear, red Taiga or Boreal Biome spruce, fir and pine. fox, squirrel, and amphibians like Hyla, Rana, : World’s largest land The litter derived from conifer needle etc. biome-North America and (leaf) is decomposed very slowly and is The productivity is lower than those of any Eurasiasouthern margins not rich in nutrients (humus content is other forest ecosystem of the tundra zone. low) giving thin podzols and are nut- ri- ent-poor soils. Deciduous and trees shed their leaves Fauna are the familiar vertebrates and in- Temperate Deciduous in cold season -an adaptation for pro- vertebrat Biome (North western tection against the winter snow and Europe-British Type Climate frost. Species include Oak, Elm, Ash, Birch, Beech, and Poplar Temperate Rainforest Big coniferous trees dominate- Doug- vertebrates and invertebrates Grizzly bears- Biome : Northwestern las fir, Western red cedar, Mountain found in Alaska. coast of North America hemlock, Western hemlock, Sitka from northern California spruce and Lodgepole pine. through southern Alaska Mosses and lichens are very common, and small areas around often growing as epiphytes southern Chile, New Zealand, Australia Download Our App Delhi Secrets 9 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Trees with small broad leaves,widely Fire is a hazardous factor Adaptation of the spaced and never very tall. plants enables them to regenerate quickly Temperate Deciduous Regions with adequate rainfall are in- after being burnt Biome (Mediterranean habited by low, broad-leafed evergreen Climate trees-evergreen oaks. Thus species here are drought tolerant. Sub-Tropical Deciduous Sub-Tropical Deciduous Biome : Eastern Not much animal diversity Biome : Eastern China, China, South Eastern USA South Eastern USA Steppe or Temperate Practically treeless Grasses-shortes,fresh and nutri- large herbivores like bison, antelope, cattle, tious. Pole ward-increase in precip- rodents, prairie dog, wolves, and a rich and Grassland Biome itation-transitional zone of wooded diverse array of ground nesting bird steppes where some conifers gradual- ly appear. Tropical Deciduous Biome Teak, neem, bamboos, sal, shisham, Drought-deciduous forest; dry forest; dry (Monsoon Climate) sandalwood, khair, mulberry. deciduous forest; tropical deciduous forest. Tall grass and short trees. Deciduous, Savannah biome is rich in mammal, bird and shedding in cool, dry season to prevent reptile diversity excessive loss of water through tran- Drought-deciduous forest; spiration. dry forest; dry deciduous Have broad trunks, with water-storing forest; tropical deciduous devices to survive through the pro- forest. longed drought. Umbrella shaped, exposing only a nar- row edge to the strong winds. Evergreen trees, plants struggle up- In the coastal areas and brackish swamps, wards (most epiphytes) for sunlight mangrove forests thrive Tropical Rain Forest Biome resulting in a peculiar layered arrange- : High temperature and ment (canopy). rainfall. Well-developed layering of understo- rey vegetationdense that hardly any light reaches ground level 1. Biosphere - is a part of the earth where life can exist. 2. Biosphere represents a highly integrated and interacting zone comprising of atmosphere (air), hydrosphere (water) and lithosphere (land ) 3. It is a narrow layer around the surface of the earth. Download Our App Delhi Secrets 10 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 4. Biosphere is absent at extremes of the North and South poles, the highest mountains and the deepest oceans, since existing hostile conditions there do not support life. 5. The energy required for the life within the biosphere comes from the sun. organisms are not uniformly distributed throughout the biosphere. AQUATIC ECOSYSTEM Characteristics Fresh water ecosystem are classified as lotic (moving water) or lentic (still or stagnant Fresh Water Ecosystem water). Lotic water system includes freshwater streams, springs, rivulets, creeks, brooks, and rivers. Lentic water bodies include pools, ponds, some swamps, bogs and lakes. Nearly three – quarter of earth’s surface is covered by ocean with an average depth Marine Ecosystem of 3,750 m and with salinity 35 ppt, (parts per thousand), about 90 per cent of which is sodium chloride Coastal bays, river mouths and tidal marshes form the estuaries. In estuaries, fresh Estuaries water from rivers meet ocean water and the two are mixed by action of tides. Estuaries are highly productive as compared to the adjacent river or sea. Coral reefs are built by and made up of thousands of tiny animals—coral “polyps”— Coral reef that are related to anemones and jellyfish. When the coral polyps die, they shed their skeleton [coral] on which new polyps grow. wetlands are transition zones (eco tone) between terrestrial and aquatic ecosystems eg. Static or flowing, fresh, brackish or saline, Includes areas of marine water the depth Mangrove of which at low tide does not exceed 6 m. e.g. Mangroves, lake littorals , floodplains and other marshy or swampy areas. Has hydrophytes and hydric soils. Occupy 18.4% of the country’s area of which 70% are under paddy cultivation  Download Our App Delhi Secrets 11 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 3 FUNCTIONS OF AN ECOSYSTEM  Function of an ecosystem is a broad, vast and complete dynamic system : Energy flow Nutrient cycling (biogeochemical cycles) Ecological succession or ecosystem development  ENERGY FLOW : Energy is the basic force responsible for all metabolic activities. The flow of energy from producer to top consumers is called energy flow which is unidirectional. Trophic level interaction in an ecosystem gives an idea about the energy flow through the ecosystem. 1. Ecosystem is maintained by the cycling energy and nutrients obtained from different external sources with Sun being primary source of energy for all ecosystems on Earth. 2. Photosynthetically Active Radiation (PAR) is the amount of light available for photosynthesis. 3. Plants capture only 2-10 per cent of the PAR and this small amount of energy sustains the entire living world. 4. TROPHIC LEVEL- The trophic level of an organism is the position it occupies in a food chain. The trophic level is the number of steps an organism is from start of the chain. 5. A given species may occupy more than one trophic level in the same ecosystem at the same time. 6. At the first trophic level, primary producers use solar energy to produce organic material through photosynthesis. The herbivores at the second trophic level use the plants as food which gives them energy. 7. A large part of this energy is used up for the metabolic functions of these animals such as breathing, digesting food, supporting growth of tissues, maintaining blood circulation and body temperature. 8. The carnivores at the next trophic level feed on the herbivores and derive energy for their sustenance and growth. 9. If large predators are present, they represent still higher trophic level and they feed on carnivores to get energy.  Trophic level interaction involves Food Chain : The order of living organisms in a community in which one organism consumes other and is itself consumed by another organism to transfer energy is called a food chain. Food chain is structured differently for different species in different ecosystems. Eg. CORN -RAT- OWL, CARROT- RABBIT- FOX- LION, GRASS -GRASSHOPPER -FROG -PYTHON -EAGLE. Download Our App Delhi Secrets 12 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 1. Grazing food chain : Begins with autotrophs. Energy and nutrients move from plants to the herbivores consuming them, and to the carnivores or omnivores preying upon the herbivores. 2. Detrital food chain : Begins with dead organic matter. In a detrital food chain, dead organic matter of plants and animals is broken down by decomposers, e.g., bacteria and fungi, and moves to detritivores and then carnivores. Food Web : Food web can be defined as ‘a network of interconnected food chains so as to form a number of feeding relationships amongst different organism of a biotic community. It provides stability to the ecosystem- A food chain cannot stand isolated in an ecosystem and all the interconnected and overlapping food chains in an ecosystem make up a food web. A food web comprises all the food chains in a single ecosystem and each living thing in an ecosystem is a part of multiple food chains. 10% rule- The number of trophic levels in the grazing food chain is restricted as the transfer of energy follows 10 per cent law – only 10 per cent of the energy is transferred to each trophic level from the lower trophic level. Download Our App Delhi Secrets 13 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY  Ecological Pyramids- An ecological pyramid is a graphical representation of the relationship between different organisms in an ecosystem. A. Pyramid of Biomass : It shows the amount of biomass (living or organic matter present in an organism) present per unit area at each trophic level. It is drawn with the producers at the base and the top carnivores at the top. Each trophic level has a certain mass of living material at a particular time called standing crop, which is measured as the mass of living organisms (biomass). Upright Pyramid of Biomass- Ecosystems found on land mostly have pyramids of biomass with large base of primary producers with smaller trophic level perched on top, hence the upright pyramid of biomass Inverted Pyramid of Biomass-A reverse pyramidal structure is found in most aquatic ecosystems where the pyramid of biomass may assume an inverted pattern. B. Pyramid of Numbers : It is the graphic representation of number of individuals per unit area of various trophic levels. Large number of producers tends to form the base whereas lower number of top predators or carnivores occupies the top. Example= In an aquatic ecosystem or grassland areas, autotrophs or producers are present in large number per unit area. The producers support a lesser number of herbivores, which in turn supports fewer carnivores. Upright Pyramid of Numbers - The number of individuals decreases from the lower level to the higher level. Usually found in the grassland ecosystem (grass occupies the lowest trophic level because of its abundance) and pond ecosystem. Inverted Pyramid of Numbers- The number of individuals increases from the lower level to the higher trophic level, for example, the tree ecosystem. C. Pyramid of Energy It is a graphical structure representing the flow of energy through each trophic level of a food chain over a fixed part of the natural environment. It represents the amount of energy at each trophic level and loss of energy at each is transferred to another trophic level. Also called as trophic pyramid or ecological pyramid. The energy pyramid is always upward because energy decreases as one move through the trophic levels from the bottom to the top of the pyramid. Download Our App Delhi Secrets 14 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY  ECOLOGICAL PRODUCTIVITY : Ecological productivity refers to the primary fixation of solar energy by plants and the subsequent use of that fixed energy by plant- eating herbivores, animal-eating carnivores, and the detritivores that feed upon dead biomass. Gross primary productivity is the total amount of energy that is fixed by plants, while net primary productivity is smaller because it is adjusted for energy losses required to support plant respiration. Gross and net secondary productivities refer to herbivorous animals, while tertiary productivities refer to carnivores. Ecologists refer to the productivity of green plants as primary productivity. Different productivity of various ecosystems - Because of differences in the availabilities of solar radiation, water, and nutrients, the world’s ecosystems differ greatly in their Ecological Productivity. Ecological efficiency – ration between the amount of energy acquired from lower trophic level and the amount of energy transferred to higher trophic level , also called as landman’s efficiency it ranges from 5-35% Marine primary productivity is high near coastline , upwelling- planktons , algal beds and coral reef have highest net primary productivity. Bioaccumulation - A Gradual accumulation of contaminants by species in concentration that are higher than surrounding Environment. Download Our App Delhi Secrets 15 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Bioconcentration is a direct uptake of of substances by living organism from medium via Skin, gills lungs & subsequent concentration of that substances within organism tissue to level that exceeds ambient environmental concentration. But it does not includes direct eating/ consuming of contaminant. Biomagnification :-Tendancy of pollutants to concentrate as they move from one trophic level to the next. also called as Bioamplification  NUTRIENT CYCLING : a) Biogeochemical cycles refer to the flow of chemical elements and compounds like oxygen, carbon, nitrogen, phosphorous, and Sulphur between organisms and the physical environment. Biogeochemical cycles can be either gaseous (reservoir pool is the atmosphere) or sedimentary (reservoir pool is the Earth’s crust). GASEOUS BIOGEOCHEMICAL CYCLES 1) Carbon cycle 1. Carbon enters into the living world in the form of carbon dioxide through the process of pho- to synthesis as carbohydrates. 2. These organic compounds (food) are then passed from the producers to the consumers (herbivores and carnivores). 3. This carbon is finally returned to the surrounding medium by the process of respiration or decomposition of plants and animals by decomposers. 4. Carbon is also recycled during the burning of fossil fuels. 2) Nitrogen cycle : 1. Nitrogen is present in the atmosphere in an elemental form and as such it cannot be utilized by living organisms. 2. The elemental form of nitrogen is converted into combined state with elements such as H, C, O by certain bacteria, so that it can be readily used by the plants. Nitrogen fixing Bacteria - Some bacteria can turn Nitrogen in to ammonia by the process known as nitrogen fixation. 3. Examples - Azotobacter, Achaea etc. Denitrifying Bacteria - These bacteria metabolize nitrogenous compounds. Download Our App Delhi Secrets 16 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY  Biological Nitrogen Fixation Examples : AGRICULTURAL SYSTEMS NATURAL SYSTEMS 1. Crop Plant associated 1. legume-rhizobia (symbiotic) 2. Legume-rhizobia (symbiotic) 2. Azolla-cyanobacteria (symbiotic) 3. Azolla-cyanobacteria (symbiotic) 3. cycadcyanobacteria (symbiotic) 4. cereal-association bacteria 4. nonlegume-Frankia (symbiotic) 5. cereal-endophylic bacteria 5. cereal-association bacteria 6. cereal-endophylic bacteria PASTURES AND FODDER PLANT ASSOCIATED FREE-LIVING - cyanobacteria 1. legume-rhizobia (symbiotic) 1. heterotrophic bacteria 2. cereal-association bacteria 2. autotrophic bacteria 3. cereal-endophylic bacteria 3) Water cycle : The evapouration of water from ocean, rivers, lakes, and transpiring plants takes water in the form of vapours to the atmosphere. This vapourised water subsequently cools and condenses to form cloud and water. This cooled water vapour returns to earth as rain an snow. 4) Oxygen cycle : The oxygen cycle is the cycle that helps move oxygen through the three main regions of the Earth, the Atmosphere, the Biosphere, and the Lithosphere (largest reservoir of oxygen)  2) SECONDARY BIOGEOCHEMICAL CYCLE. 1) Sulphur cycle : 1. Sulphur occurs in all living matter as a component of certain amino acids 2. It is abundant in the soil in proteins and, through a series of microbial transformations, ends up as sulphates usable by plants. Download Our App Delhi Secrets 17 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 3. Sulphur-containing proteins are degraded into their constituent amino acids by the action of a variety of soil organism 2) Phosphorous cycle : 1. When it rains, phosphates are removed form rocks (via weathering) and are distributed throughout both soils and water. 2. Plants take up the phosphate ions from the soil which then moves from plants to animals when herbivores eat plants and carnivores eat plants or herbivores 3. The phosphates absorbed by animal through consumption returns to the soil through the excretion, as well as final decomposition of plants and animals.  ECOLOGICAL SUCCESSION : Ecological succession is the process by which the structure of biological community evolves over time. The entire series of communities that is characteristic of a given site is called a sere. In ecological terminology, the developmental stages of a community are known seral stages and the final stage as the climax community. entire series of communities that is characteristic of a given site is called a sere. Stages of ecological succession : 1. Pioneer community 2. Intermediate stage 3. Climax community Types Of Succession : 1. Primary Succession-It occurs in essentially lifeless areas- regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. 2. Secondary Succession-It occurs in areas where a community that previously existed has been removed; it is typified by smaller-scale disturbances that do not eliminate all life and nutrients from the environment. 3. Other types of Ecological Succession 1. AUTOTROPHIC SUCCESSION- characterized by early and continued dominance of autotrophic organisms like green plants that begins in a predominantly inorganic environment and the energy flow is maintained indefinitely. 2. ALLOGENEIC SUCCESSION- In this, the replacement of the existing community is caused largely by any other external condition and not by the existing organisms. 3. AUTOGENIC SUCCESSION- It refers to that type when the community itself, as a result of its reactions with the environment, modifies its own environment and thus causing its own replacement by new communities Download Our App Delhi Secrets 18 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 4. HYDRARCH SUCCESSION- Plant succession starting on relatively shallow water, such as ponds and lakes, and culminating in a mature forest. 5. XERARCH SUCCESSION- Plant succession starting on bare ground or rock and culminating in a mature climax forest. The pioneer species, such as lichens and mosses, result in the gradual accumulation of soil. 6. MICRO SUCCESSION- Succession of microorganism predominantly in organic environment ,progressive decline in energy content eg. Protozoa  Ecosystem services : Ecosystem services are the benefits people obtain from ecosystems. These include provisioning, regulating, and cultural services that directly affect people and supporting services needed to maintain the other services. The Millennium Ecosystem Assessment (MA) was initiated in 2001 by United Nations, whose objective was to assess the consequences of ecosystem change for human well-being, the scientific basis for action needed to enhance the conservation and sustainable use of those systems and their contribution to human well-being provisioning services- The “products” obtained from ecosystem Foods, Fibers, Ornamentals, Medicines, Biofuels, Fresh water, Genetic resources Regulating services - Benefits obtained from the regulation of ecosystem processes Climate regulation, Flood prevention, Erosion control, Pest control, Pollination, Seed dispersal, Disease regulation Cultural services - Nonmaterial benefits obtained from ecosystems Educational, Recreational Sense of place, Spiritual, Cognitive development, Stress relief, Gardening Services necessary for the production of all other ecosystem services Biodiversity Nutrient recycling Primary productivity  Ecosyste Function : Biodiversity functional traits species richness ecological processes genetic diversity socio-economic systems biotic interactions biophysical structure Download Our App Delhi Secrets 19 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY  Some Terminologies- NATURAL CAPITAL- It includes those elements of the nature that provide valuable goods and services to humans, such as the stock of forests, food, clean air, water, land, minerals, etc. It includes those elements of the nature that provide valuable goods and services to humans, such as the stock of forests, food, clean air, water, land, minerals, etc NATURAL CAPITAL ACCOUNTING-Also called as environmental-economic accounting. It is a tool that can help to gain an understanding of the interaction between the economy and the environment. It can be used to measure the state of ecosystems, flows of ecosystem services as well as changes in stocks and flows of natural resources in relation to economic changes. SEEA- System of Environmental-Economic accounting. It is a statistical system that brings together economic and environmental information into a common framework to measure the condition of the environment, the contribution of the environment to the economy and the impact of the economy on the environment. NCAVES- Natural Capital Accounting and Valuation of Ecosystem Services- A project launched by The United Nations Statistics Division, UNEP, the Secretariat of the Convention on Biological Diversity, and the European Union. The project is funded by the European Union, aims to assist the five participating partner countries, namely Brazil, China, India, Mexico and South Africa, to advance the knowledge agenda on environmental and ecosystem accounting. The project review policy demands, data availability and measurement practices in order to advance and mainstream natural capital accounting. THE ECONOMICS OF ENVIRONMENT AND BIODIVERSITY (TEEB) Based in Geneva, Switzerland at the International Environment House, the TEEB office is hosted by the UNEP. It is a global initiative focused on “making nature’s values visible” whose principal objective is to mainstream the values of biodiversity and ecosystem services into decision-making at all levels. In October 2010 it released its report “Mainstreaming the Economics of Nature : A Synthesis of the Approach, Conclusion, and Recommendation of TEEB” and launched the Bank of Natural Capital to communicate it’s findings to the general public. It is guided by three core principles- Recognizing value in ecosystems can sometimes ensure conservation; Demonstrating value in economic terms is often useful for policy makers and other such as business; Capturing value involves the introduction of mechanisms that incorporate the values of ecosystems into decision making. IPBES GLOBAL ASSESSMENT REPORT The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) is an independent intergovernmental body established in 2012 with now over 130 member states around the world. It is the first intergovernmental Report of its kind and builds on the landmark Millennium Ecosystem Assessment of 2005, introducing innovative ways of evaluating evidence. Download Our App Delhi Secrets 20 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY It the most comprehensive scientific evaluation ever made of the state of our nature, and gives a detailed account of health of the species that inhabit this earth, and the condition of habitats that they live in and depend upon. The Report concluded that the second-fastest mass extinction event in planetary history is underway. The Report highlighted the importance of indigenous community in conservation. It notes, “Nature managed by Indigenous People and Local Communities is under increasing pressure but is generally declining less rapidly than in other lands.” This is significant since “at least” a quarter of the world’s land area is “traditionally owned, managed, used or occupied by indigenous people”..  Download Our App Delhi Secrets 21 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 4 FOREST VEGETATION IN INDIA NAME RAINFALL REGION CHARACTERISTICS Near the equator, warm and wet Trees- rosewood, mahogany, ebony, Bam- throughout the year. boos and reeds Reach heights>= 60 m. > 200 cm, Occupy about 7% of the earth’s land sur- Evergreen forests-western slopes of the Tropical 15 to 30 face. Western Ghats in States, hills of Jaintia and Evergreen degree Has more than half of the world’s plants Khasi Forests Celsius. and animals. Animals-elephants, monkey, lemur and deer. One horned rhinoceros are found in the jun- gles of Assam and West Bengal. Tropical Most widespread forests of India. Also Most widespread forests of India. Also called Deciduous 200 -70 cm. called the monsoon forests and spread the monsoon forests and spread over the Forests over the region receiving. region receiving. Mostly in the eastern part of the coun- Teak is the most dominant species of this try. forest. -Bamboos, sal, shisham, sandalwood, Moist North-eastern states, along the foothills khair, kusum, arjun, mulberry are other com- Deciduous 200 -70 cm. of the Himalayas, Jharkhand, West Orissa mercially important species. Forests and Chhattisgarh, eastern slopes of the Western ghats Rainier parts of the peninsular pla- Trees- Teak, Sal, Peepal, Neem. -Large parts- Dry teau and the plains of Bihar and Uttar cleared for cultivation and some parts are Deciduous 100-70c m Pradesh. used for grazing. Forests Animals- Lion, tiger, pig, deer and elephant. Birds, lizards, snakes, and tortoises etc Thorn Thorn Thorn Forests and Scrubs Vegetation- thorny trees and bushes. Aca- Forests and Forests cias, palms, euphorbias and cacti are the Scrubs and Scrubs main plant species. Trees- scattered, have long roots penetrating deep into the soil in order to get moisture. The stems are succulent to conserve water. Leaves are mostly thick and small to mini- mize evapouration Download Our App Delhi Secrets 22 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Moses & Lichens Alpine Grassland Be- TUNDRA ALPINE FOREST MONTANE FOREST yond 3600 mt Shrubs, Scrubs 3000- 3600 WOODLAND ARID GRASSLAND DESERT SHRUB mt- Temperature forests, Grassl and Sil- Animals-Kashmir stag, spotted dear , wild ver fir, Juniper, Pine, Birches 1500-3000 sheep, jackrabbit, Tibetan antelope, yak, Montane mt – snow leopard, squirrels, Shaggy horn wild < 70 cm Forests Temperature forests with conifers Pine, ibex, bear and rare red panda, sheep and Deodar, Silver Fir, Spruce, Cedar (south- goats with thick hair ern slopes of Himalayas) 1000-2000 mt- Wet temperate, evergreen broad leaf forest Oak & Chestnut THE INDIA STATE OF FOREST REPORT IFSR The National Forest Policy of India, 1988 envisaged a goal of achieving 33 per cent of the geographical area of the country under forest & tree cover. India State of Forest Report (ISFR)i is a biennial publication of Forest Survey of India (FSI), an organization under the Ministry of Environment, Forest & Climate Change, Government of India. The principal mandate of the Forest Survey of India (FSI)ii is to conduct survey and assessment of forest resources in the country. FSI REPORT HIGHLIGHTS : Total forest and tree cover - 80.73 million ha, 24.56% of the geographical area of the country. The Total Forest cover- 7,12,249 sq km which is 21.67% of the geographical area of the country. Target is to achieve 33% of area under forest cover. Tree cover is 2.89% of the geographical area of the country. There is an increase of 5,188 sq. km in the total forest and tree cover of the country. Range increase in forest cover has been observed in open forest followed by very dense forest and moderately dense forest. Top three states showing increase in forest cover are Karnataka, Andhra Pradesh and Kerala. Area-wise Madhya Pradesh has the largest forest cover, followed by Arunachal Pradesh, Chhattisgarh, Odisha and Maharashtra.  DEFORESTATION : Indiscriminate felling of trees as a result of urbanization, industrialization, mining operations, and use of wood for domestic and other purposes, have caused heavy depletion of forests. Download Our App Delhi Secrets 23 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Causes : Shifting cultivation In this practice a patch of land is cleared, vegetation is burned and the ash is mixed with the soil thus adding nutrients to the soil. This patch of land is used for raising crops for two to three years, and the yield is modest. development project- Development projects like the hydroelectric projects, large dams and reservoirs, laying down of railway lines and roads Fuel Requirements- for firewood with ever growing population increases greater pressure on the forests Raw Material Requirements- Wood is used as a raw material by various industries for making paper, plywood, furniture, match sticks, boxes, crates, packing cases, etc  SOCIAL FORESTRY : Management and protection of forests and afforestation on barren lands with the purpose of helping in the environmental, social and rural development. National Agroforestry Policy 2014 Objectives : Promote agroforestry to increase farm income and livelihoods of rural households, especially the small and marginal farmers. Protect and stabilise ecosystems, and promote resilient cropping and farming systems to minimise the risk during extreme climatic events. Provide raw material to wood-based industries, creating new avenues for rural employent, and reduce pressure on the forests. To develop capacity and strengthen research in agroforestry and create a massive people’s movement for achieving these objectives. Nagar Van Scheme (Ministry Of Environment, Forest And Climate Change) : 1. It aims at developing 200 Nagar Van (Urban Forests) across the country in next five years in cities having Municipal Corporation or Municipalities by involving local communities, educational institutions, local bodies, NGOs etc. 2. Minimum of 20 ha of forests will be created in the city-either on existing forest land or on any other vacant land offered by urban local bodies. Van Udyan once established will be maintained by the State Government. 3. Cities authorities will be encouraged to have a city forest comprising area up to 100 ha in forest area within their jurisdiction. In part, paid for by the CAMPA funds. 4. Also linked to the Schools Nursery Yojana that aims to build lasting bond between students and nature. Warje Urban Forest in Pune (Maharashtra) - role model for the Scheme.  National Afforestation Programme : Formulated by the merger of four 9th Plan centrally sponsored afforestation schemes of the MoEFCC. Objective is ecological restoration of degraded forests and to develop the forest resources with peoples’ participation, with focus on improvement in livelihoods of the forest-fringe communities, especially the poor. Download Our App Delhi Secrets 24 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY  Green India Mission : Under the umbrella of National Action Plan for Climate Change, launched in 2014. GREEN INDIA MISSION (GIM) : The primary aim is to protect, restore and enhance India’s diminishing forest cover. Objectives : Growth in forest or tree cover to 5 million hectares (mha) and increase the quality of forest cover in another 5 million hectares of forest or non-forest lands. sub-targets : Increase the quality of degrading moderately dense forests – 1.5 million hectares (ha). Ecologically restore open forests which are being degraded – 3 million hectares (ha) Grasslands revival – 0.4 million hectares Wetlands revival – 0.10 million hectares Ecological restoration of shifting cultivation areas, mangroves, scrub, ravines, cold deserts, & abandoned mining areas – 1.8 million hectares with different sub-targets. Increase in forest cover in urban areas and its outskirts – 0.20 million hectares. Increase forest and tree cover on marginal agricultural lands/fallows and other non-forest lands which comes under agroforestry – 3 million ha. Increase forest-based livelihood income for about 3 million households in and around these forest areas. Increase Carbon Dioxide sequestration to a range of 50 to 60 million tonnes by 2020  National Bamboo Mission : Centrally Sponsored Scheme in 2006-07 and was subsumed under Mission for Integrated Development of Horticulture (MIDH) during 2014-15 and continued till 2015-16. Restructured in 2018-19 for holistic development of complete value chain of sector. In 2017, Indian Forest Act 1927 was amended to remove bamboo from the category of trees. This allows cultivation and felling of bamboo and its products without any felling and transit permissions outside forests.  DESERTIFICATION : It is the destruction of biological potential of the land which can ultimately lead to desert like conditions. In arid and semiarid regions, the restoration of the fragile ecosystem is very slow, and issues like deforestation, mining enhances the desertification. Desertification is a main problem faced by desert adjoining areas, which stretches across parts of Rajasthan, Gujarat, Punjab and Haryana. The cause of this process is not climatic changes, droughts, etc. but human actions. Control measures- India is a signatory to United Nations Convention to Combat Desertification (UNCCD). The National Action Programme for combating desertification was prepared in 2001 to take appropriate action in addressing the problems of desertification. Some of the major programmes currently implemented that address issues related to land degradation and desertification are Integrated Watershed Management Programme Download Our App Delhi Secrets 25 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY National Afforestation Programme National Mission for Green India The Mahatma Gandhi National Rural Employment Guarantee Scheme Soil Conservation in the Catchment of River Valley Project and Flood Prone River National Watershed Development Project for Rainfed Areas Desert Development Programme Fodder and Feed Development Scheme-component of Grassland Development including Grass Reserves, Command Area Development and Water Management programme etc ACT OBJECTIVES Compensatory It refers to the afforestation and National Compensatory Afforestation Fund (NCAF) Afforestation regeneration activities carried out under the Public account of India State Compensatory Fund Act 2016 as a way of compensating for forest Afforestation Funds under public accounts of states. land which is diverted to non- forest -Centre : state - 10 :90. purposes. For compensatory afforestation, additional compensatory afforestation, penal compensatory afforestation, net present value, catchment area treatment plan or any money for compliance of conditions stipulated by the Central Government while according approval under the provisions of the Forest (Conservation) Act, 1980. Statutory status-National Compensatory Afforestation Fund Management and Planning. Authority (NCAFMPA),State Compensatory Afforestation Fund Management and Planning Authority for utilization of State Compensatory Afforestation Fund. Constitution of a multidisciplinary monitoring group to monitor activities undertaken from these funds. Annual audit of the accounts by the Comptroller and Auditor General. Forest To check further deforestation and Restricts use of forest for non-forest purpose Restricts Conservation Act, conserve forests de- reservation of reserve forests. 1980 Regulates diversion of forest land by way of lease to private industries and individuals. Restricts clear felling of trees. Constitution of Advisory Committee for grant of approval for any of the activities above Download Our App Delhi Secrets 26 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Indian Forest Act, To consolidate laws relating to Establishes three classes of forests-Reserve Forest , 1927 forests, transit of forest produce Protected Forest and Village Forest. Detailed process of and duty leviable on timber and settlement of rights through the FSO. forest produce Deals with control over forests not being the property of the Government. Deals with duty on timber and other forest produce and in transit. Regulate the rights of the owners in drift and stranded timber. Power to reserve specific tree species in reserve forest The Biological Conservation of Biological Diversity, Estb National Biodiversity Authority, State Biodiversity Diversity Act 2002 sustainable use of its components Board. and equitable sharing of the Requires the Central Government to develop National benefits of biological resources. Strategies, plans, programmes for the objectives of the Act. Requires the Central Govt. to notify threatened species and the State Govt. to notify biodiversity heritage sites. Mandates every local body to constitute Biodiversity Management Committee. Provides for establishment of Local Biodiversity Funds  Download Our App Delhi Secrets 27 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY 5 AQUATIC ECOSYSTEM 1) Fresh water ecosystems- The salt content of fresh bodies is very low, always less than 5 ppt (parts per thousand). E.g lakes, ponds, pools, springs, streams, and rivers 2) Marine ecosystems - the water bodies containing salt concentration equal to or above that of sea water (i.e., 35 ppt or above). E.g shallow seas and open ocean 3) Brackish water ecosystems – these water bodies have salt content in between 5 to 35 ppt. e.g. estuaries, salt marshes, mangrove swamps and forests.  Estuarine Ecosystem : Where a river or a stream opens into the sea (mouth of the river). They are transition zone (Ecotone) between river and maritime environments. They are enclosed coastal area of brackish water (salinity varies between 0-35 ppt) with one or more rivers or streams flowing into it, and with a free connection to the open sea. Freshwater carrying fertile silt and runoff from the land mixes with the salty seawater. They support habitats, such as mangroves, salt marshes, sea-grass, mudflats etc. OSMOREGULATION : Plants and animals in the estuaries are subjected to variations in salinity to which they are adapted. Importance Of Estuaries : They are transition zones More productive than wetlands Experience very little wave action Precipitation of clay and alluvium particles in the estuarine region is high Store and recycle nutrients, traps sediment and form a buffer between coastal catchments and the marine environment. They also absorb, trap and detoxify pollutants, acting as a natural water filter. Estuaries with their wetlands, creeks, lagoons, mangroves and sea-grass beds are rich in natural resources including fisheries Estuarine Vegetation : Capable of surviving in brackish waters. Phytoplanktons of estuaries are diatoms, dinoflagellates, green algae, bluegreen algae. Towards the sea coast, there are large algae and seagrasses. Near the mouth of the rivers and deltas, there are mangrove forests There are all kinds of terrestrial or land-based plants and animals, such as wood storks, pelicans, coniferous and deciduous trees and butterflies. Estuaries are also home to unique aquatic plants and animals, such Download Our App Delhi Secrets 28 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY as sea turtles, sea lions, sea catfish, saltworts, eelgrass, salt grasses, cordgrasses, seagrass, sedge, bulrush etc. India Estuarine Ecosystem : The Country has 14 major, 44 medium and 162 minor rivers drains into the sea through various estuaries. Most of India’s major estuaries occur on the east coast. In contrast, the estuaries on the west coast are smaller. Aquatic Organisms : Classified Based On Zone Of Occurrence : Neuston : live at the air-water interface, e.g. floating plants. Periphyton : Attached to stems and leaves of rooted plants or substances emerging above the bottom mud Plankton : Microscopic floating organisms- both microscopic plants and animals Nekton : Powerful swimmers that can overcome the water currents. Benthos : Living at the bottom of the water mass actors limiting the productivity of aquatic habitats : Sunlight, dissolved oxygen, temperature Factors Limiting the Productivity of Aquatic Habitats : Sunlight and oxygen are most important limiting factors of the aquatic ecosystems whereas moisture and temperature are the main limiting factors of terrestrial ecosystem In fresh water the average concentration of dissolved oxygen is 0.0010 per cent (also expressed as 10 parts per million or 10 ppm) by weight, which is 150 times lower than the concentration of oxygen in an equivalent volume of air. When the dissolved oxygen level falls below 3-5 ppm, many aquatic organisms are likely to die. Photic zone : A. It is the upper layer of the aquatic ecosystems, up to which light penetrates and within which photosynthetic activity is confined. B. The depth of this zone depends on the transparency of water. C. Both photosynthesis and respiration activity takes place. D. photic (or “euphotic”) zone is the lighted and usually well-mixed portion that extends from the lake surface down to where the light level is 1% of that at the surface. Aphotic zone : The lower layers of the aquatic ecosystems, where light penetration and plant growth are restricted forms the aphotic zone. Only respiration activity takes place. aphotic zone is positioned below the littoral and photic zones to bottom of the lake where light levels are too low for photosynthesis. Respiration occurs at all depths so the aphotic zone is a region of oxygen consumption. This deep, unlit region is also known as the profundal zone. Download Our App Delhi Secrets 29 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Zones Of Lakes And Ponds Littoral zone - topmost , near shore Limnetic zone - near surface open water surrounded by littoral zone , farther from shore , extending to depth penetrated by light.occupied by planktons , zooplanktons , higher animals and produces food and oxygen that supports most of lake consumers Profundal zone - deepest zone , much denser than above two , little light and oxygen Benthic zone - actual bottom of lake , cool temperature , low oxygen , accompanied by decomposers , detritus Zones of streams and river Source zone Transition zone Floodplain zone  Wetlands And Mangroves : wetlands are transition zones (eco tone) between terrestrial and aquatic ecosystems eg. Static or flowing, fresh, brackish or saline, Includes areas of marine water the depth of which at low tide does not exceed 6 m. e.g. Mangroves, lake littorals , floodplains and other marshy or swampy areas. Has hydrophytes and hydric soils. Occupy 18.4% of the country’s area of which 70% are under paddy cultivation.  Wetland Classification : Inland Wetland : A. NATURAL-e.g. Lake/pond, Cut-off meander, Swamp, Marsh, Waterlogged. B. MAN MADE- e.g. Reservior, Tanks. Coastal Wetland : I. NATURAL-e.g. Estuary, Lagoon, Creek, Coral Reef, Mangroove. II. NATURAL-e.g. Aquaculture, Salt Pan. Types Of Wetlands 1. MARINE - Coastal wetlands including coastal lagoons, rocky shores, and coral reefs. 2. ESTUARINE - Including deltas, tidal marshes, and mangrove swamps. 3. LACUSTRINE - Wetlands associated with lakes. 4. RIVERINE - Wetlands along rivers and streams. 5. PALUSTRINE - Meaning “marshy” - marshes, swamps and bogs. 6. HUMAN-MADE - WETLANDS such as fish and shrimp ponds, farm ponds, irrigated agricultural land, saltpans, reservoirs, gravel pits, sewage farms and canals. Also termed as urban wetland. Download Our App Delhi Secrets 30 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Functions Of Wetland Biodiversity For Climate And Biodiversity- 30% of land-based carbon is stores in peatlands. Role in flood mitigation by controlling the rate of runoff Act as a riparian buffer against erosion and pollutants. Habitat to aquatic flora and fauna, numerous species of native and migratory birds For Clean Water- Swaps and rewards remove pollutants. Water purification, filtration of sediments and nutrients from surface water. Nutrients recycling, groundwater recharging and stabilisation of local climate. For Jobs- One billion people depend on wetlands for their livelihoods. For Economies- Wetlands provide USD 47 trillion in essential services annually Important resource for sustainable tourism. Genetic reservoir for various species of plants (especially rice). Reasons For Depletion : Excessive pollutants dumped into wetlands beyond the recycling capacity. Habitat destruction and deforestation. Conversion of wetlands for agriculture and encroachments. Overfishing and fish farming (Aquaculture). Overgrazing in marshy soils. Removal of sand from beds near seas makes the wetland vulnerable to wave action and tidal bore.  Peatland- are a heterogeneous mixture of plant material that had accumulated in a water-saturated area and are only partially decomposed due to the absence of oxygen. I. Types of peat are – swamp forests, fens, bogs or mires. Formed in areas with permanent water saturation i.e. either terrestrialisation or palaudification II. They are mostly found in permafrost regions towards the poles and at high altitudes, in coastal areas, beneath tropical rainforest and in boreal forests. III. Countries with the largest peatland areas are – Russia, Canada, Indonesia, USA, Finland etc. Brazzaville Declaration was signed to promote better management and conservation of Cuvette Centrale Region in Congo Basin IV. Global Peatlands Initiatives (GPI) : is an initiative by leading experts and institutions to save peatlands as the world’s largest terrestrial organic carbon stock and to prevent it from being emitted  Ageing of Lakes : Like any organism, lakes are born as they originate by various geological and geomorphic events, and ‘grow’ with time to change in their various morphological and functional characteristics and eventually die. They receive their water from surface runoff (sometimes also groundwater discharge) and along with it various chemical substances and mineral matter eroded from the land. Over periods spanning millennia, ‘ageing’ occurs as the lakes accumulate mineral and organic matter and gradually, get filled up. Download Our App Delhi Secrets 31 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY  Eutrophication : Greek word – Eutrophia means adequate & healthy nutrition. Eutrophication is a syndrome of ecosystem, response to the addition of artificial or natural nutrients such as nitrates and phosphates through fertilizer, sewage, etc that fertilize the aquatic ecosystem. It is primarily caused by the leaching of phosphate and - or nitrate containing fertilisers from agricultural lands into lakes or rivers. The growth of green algae which we see in the lake surface layer is the physical identification of an Eutrophication. Some algae and blue-green bacteria thrive on the excess ions and a population explosion covers almost entire surface layer is known as algal bloom. This growth is unsustainable, however. As Algal Bloom covers the surface layer, it restricts the penetration of sunlight. Diffusion of gas from atom Oxygen is required by all respiring animals in the water and it is replenished by diffusion and photosynthesis of green plants.  Mangrove in India : 1. Sundarbans are the largest single block of tidal holophytic mangroves of the world. 2. Bhitarkanika (Orissa), which is the second largest in the Indian sub continent, harbour high concentration of typical mangrove species and high genetic diversity 3. Gujarat mangroves found mainly in Gulf of Kachchh and the Kori creek. coastal zone of Kerala is very sparse and thin. 4. profusion in the intertidal mudflats on both side of the creeks in the Godavari Krishna deltaic regions of Andhra Pradesh. 5. scrubby and degraded occur along the intertidal region of estuaries and creeks in Maharashtra, Goa and Karnataka 6. On the Andaman & Nicobar Islands, the small tidal estuaries, neritic inlets and the lagoons support a dense and diverse undisturbed mangrove flora. Download Our App Delhi Secrets 32 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY Conservation Of Mangroves : Coastal Regulation Zone Rules are also protecting mangroves. SMART (Special Monitoring and reporting Tool) monitoring in the Sundarbans empowers local administration contributing to a more effective management of natural resources. Gujarat uses direct seed sowing, raised bed plantations, and fishbone channel plantations to restore degraded mangroves. Andhra Pradesh has established Eco-Development Committees and Van Samrakshan Samithi to implement conservation projects in mangrove areas. Maharashtra has been implementing restoration, protection, regeneration, and maintenance techniques to conserve mangroves. Mangrove for Future Initiative : to promote investment in coastal ecosystem conservation for sustainable development topromote an integrated ocean-wide approach to coastal.management and to building the resilience of ecosystem-dependent coastal communities. Effects of Eutrophication : Change in ecosystem : - Eutrophication eventually create detritus layer in the ponds & lakes and produces successively shallower depth of surface water. Decreased biodiversity - Algal blooms restrict the sunlight to penetrate & affects the photosynthesizing plants. It causes death of plants. New species invasion - Eutrophication may cause the ecosystem competitive by transforming the normal limiting nutrient to abundant level. This cause shifting in species composition of ecosystem. Toxicity - Some algal blooms when die or eaten, release neuro & hepatotoxins which can kill aquatic organism & pose threat to humans. E.g. Shellfish poisoning. Harmful Algal Blooms : 1. Algae or phytoplankton are microscopic organisms that can be found naturally in coastal waters. They are major producers of oxygen and food for many of the animals that live in these waters. 2. When environmental conditions are favorable for their development, these cells may multiply rapidly and form high numbers of cells and this is called an algal bloom. 3. A bloom often results in a color change in the water. Algal blooms can be any color, but the most common ones are red or brown. These blooms are commonly referred to as red or brown tides.  Why Red Tide is a misnomer? “Red Tide” is a common name for such a phenomenon where certain phytoplankton species contain pigments and “bloom” such that the human eye perceives the water to be discolored. Blooms can appear greenish, brown, and even reddish orange depending upon the type of organism, the type of water, and the concentration of the organisms. Download Our App Delhi Secrets 33 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY The term “red tide” is thus a misnomer because blooms are not always red, they are not associated with tides, they are usually not harmful, and some species can be harmful or dangerous at low cell concentrations that do not discolor the water.  National Wetlands Conservation Programme (NWCP) NWCP was implemented in the year 1985-86. Under the programme, 115 wetlands (Annexure) have been identified by the Ministry which require urgent conservation and management interventions. Aim - Conservation of wetlands to prevent their further degradation and ensuring their wise use for the benefit of local communities and overall conservation of biodiversity Criteria for Identification of Wetlands of National Importance : Criteria for identification of wetlands of national importance under NWCP are same as those prescribed under the ‘Ramsar Convention on Wetlands’ and are as given below : 1. Sites containing representative, rare or unique wetland types If it contains a representative, rare, or unique example of a natural or near-natural wetland type found within the appropriate biogeographic region. 2. Criteria based on species and ecological communities If it supports vulnerable, endangered, or critically endangered species; or threatened ecological communities. If it supports populations of plant and/or animal species important for maintaining the biological diversity of a particular biogeographic region. If it supports plant and/or animal species at a critical stage in their life cycles, or provides refuge during adverse conditions.  Distinction Between Lake and Wetland Download Our App Delhi Secrets 34 t.me/DelhiUpscSecrets_official  DELHI UPSC SECRETS  ENVIRONMENT AND ECOLOGY  Montreux Record : Montreux Record is the principal tool under the Ramsar Convention 1975, is a register of wetland sites on the List of Wetlands of International Importance. For “the conservation and wise use of all wetlands through local and national actions and international cooperation, as a contribution towards achieving sustainable development throughout the world”. Chilika lake, Orissa was placed on the Montreux Record in 1993 due to siltation, which was choking the mouth of the lake. Following the rehabilitation efforts of the government, it was removed from the Record in 2002. Loktak, Manipur was included on the Montreux Record in 1993 (signifying habitat degradation), Neknampur Lake - First FTW Lake The Neknampur Lake, Hyderabad is the largest floating treatment wetland in the country. Floating treatment wetland workson the basis of hydroponics technique. Keoladeo national park, Rajasthan was placed on the Montreux Record in 1990 due to water shortage and unbalanced grazing regime around it. 75 Ramsar Sites in 75th Year of Independence -India adds 11 more wetlands to the list of Ramsar Sites Tampara Lake Hirakud Reservoir Odisha Ansupa Lake Yashwant Sagar Madhya Pradesh Chitrangudi Bird Sanctuary Suchindram Theroor Wetland Complex Tamil Nadu Vaduvur Bird Sanctuary Kanjirankulam Bird Sanctuary Thane Creek Maharashtra Hygam Wetland Conservation Reserve Jammu and Kashmir Shallbugh Wetland Conservation Reserve RAMSAR SITES IN INDIA - STATE LOCATION Karikili Bird Sanctuary Tamil Nadu Loktak lake Manipur Pallikaranai Marsh Reserve Forest Tamil Nadu Nalsarovar Bird sanctuary Gujarat Pichavaram Mangrove Tamil Nadu Nandur Madhameshwar Maharashtra Sakhya Sagar Madhya Pradesh Nangal Wildlife Sanctuary Punjab Pala Wetlands Mizoram Nawabganj Bird Sanctuary Uttar Pradesh Khijadia Wildlife Sanctuary Gujarat Parvati Agra Bird Sanctuary Uttar Pradesh Bakhira Wildlif