UNIT-IT ECOSYSTEM AND BIODIVERSITY 2.1 ECOSYSTEM An ecosystem is a community of organisms that interact with each other and non living components for sustainable development and adaptation to changing conditions. There are different type of ecosystems around us which involves living organisms and non living organisms. If we combine all the ecosystems present on earth, it is called Biosphere. The term ecosystem was first proposed by A.GTansley (1935) who defined ecosystem as follows “Ecosystem is defined as a self-sustained community of plants and animals existing in its own environment.”Odum (1971) defined ecosystem as any unit that includes all the organisms in a given area interacting with the physical environment, so that a flow of energy give rise to a clearly defined tropic structure, biotic diversity and material cycles within the system "Michael Allaby (1983) defined ecosystem as a community of interdependent organisms together with the environment CONCEPT OF ECOSYSTEM: In an ecosystem, the interaction of life with its environment takes place at many levels. A single bacteria in the soil interacts with water, air around it within a small space while a fish in a river interacts with water and other animals, rivals in a large space. Considering the operational point of view; the biotic and abiotic components of an ecosystem are so interlinked such that their separation from each other is practically difficult. So, in an ecosystem both organisms (biotic communities) and abiotic environment (rainfall, temperature, humidity) each influence the properties with other for maintenance of life. STRUCTURE OF ECOSYSTEM A structure of Ecosystem comprise of *The Composition of biological community including, species number, biomass, life history, and distribution in space. “The quantity and distribution of non-living material, such as nutrient water, ete «The rage of condition of existence such as temperature, light. FUNCTION OF ECOSYSTEM: The rate of biological energy flow ie. production & respiration rates of the community. The rate of material or nutrient cycles “Biological or ecological regulation including both regulation of organism by environment and regulation of environment by the organisms 2.1.1 COMPONENTS OF AN ECOSYSTEM: There are two components of an ecosystem; Living components and non living components 28Non Living Components: (Abiotic) Non living components are the physical and chemical factors that directly or indirectly affect the living components e.g. air, water, land, rock ete. Non living components are also called Abiotic components. Physical factors include sunlight, water, fire, soil, air, temperature etc. Chemical factors include moisture, salinity of water, soil autrients, oxygen dissolved in water et. Living Components: Living components in an ecosystem are either producers or consumers. They are also called biotic components. Producers can produce organic components e.g. plants, can produce starch, carbohydrates, cellulose from a process called photosynthesis. Consumers are the components that are dependent on producers for their food eg. human beings and animalse Biotic Components are further classified into 3 main groups “Producers +Consumers «Decomposers or Reducers 1. Producer (Autotrophs): The green plants have chlorophyll with the help of which they trap solar energy and change it into chemical energy of carbohydrates using simple inorganic compound namely, water and carbon dioxide. This process is known as photosynthesis. The chemical energy stored by the producers is utilized partly by the producers for their own growth and survival and the remaining is stored in the plants for their future use. They are classified into two categories based on their source of food. a)Photoautotrophs: An organism capable of synthesizing its own food from inorganic substances using light as an energy source. Green plants and photosynthetic bacteria are photoautotrophs. b)Chemotrophs: Organisms that obtain energy by the oxidation of electron donors in their environments. These molecules can be organic (chemoorganotrophs) or inorganic (chemolithotrophs) 2. Consumers (Heterotrophs): The animals lack chlorophyll and are unable to synthesis their own food therefore they depend on the producers for their food. «They are known as heterotrophs (ie. heteros= others, trophs= feeder). The Consumers are of 4 types (a) Primary Consumer: (Herbivores) ie. Animal feeding on plants, e.g. Rabbit, deer, goat ete (b) Secondary Consumers: The animal feeding on Herbivores are called as secondary Consumer or primary carnivores. e.g. Cats, foxes, snakes. (© Tertiary Consumers: These are large carnivores which feed on secondary consumers. e.g. Wolves (@ Quaternary Consumers: They are also called omnivores these are largest carnivores Which feed on tertiary consumers and are not eaten up by any other animals. ¢.g. lion and Tiger. 3. Decomposers or Detrivores:Bacteria & fungi belong to this category. They break down the dead organic matter of producers & consumers for their food and release to the environment the simple inorganic and organic substance. These simple substances are reused by the producers resulting in a cyclic exchange of material between biotic & abiotic environment Eg: Bacteria, Earth worms, Beetles etc 292.1.2 ENERGY FLOW IN AN ECOSYSTEM *Biological activities require energy which ultimately comes from the sun. Solar energy is transformed into chemical energy by a process of photosynthesis this energy is stored in plant tissue and then transformed into heat energy during metabolic activities “Thus in biological world the energy flows from the sun to plants and then to all heterotrophic organisms. The flow of energy is unidirectional and non-cyclic This one way flow of energy is governed by laws of thermodynamics which states that (a) Energy can neither be created nor be destroyed but may be transformed from one form to another (b) During the energy transfer there is degradation of energy from a concentrated form (mechanical, chemical, or electrical etc.) to a dispersed form (heat) No energy transformation is 100 % efficient; it is always accompanied by some dispersion or loss of energy in the form heat. Therefore, biological systems including ecosystems must be supplied with energy on a continuous Basis. MODELS OF ENERGY FLOW IN ECOSYSTEM 1. Single Channel Energy Flow Model: The flow of energy takes place in a unidirectional manner through a single channel of producers to herbivores and carnivores. The energy captured by autotrophs does not revert back to solar input but passes to herbivores; and that which passes to herbivores does not go back to autotrophs but passes to consumers. Due to one way flow of energy, the entire system would collapse if primary source of energy were cut off. At each tropic level there occurs progressive decrease in energy which is mainly due to loss of energy as heat in metabolic reactions and also some of the energy is utilized at each tropic level, 30a iii SEO zoom raene " wr or | tntiteo corps Hoey Merggeen | [IGURE. 1434. Heng ow agram for a tke Freshwater stem) In geen ern Lndaman, 3942). 2. Y- shaped model: shows a common boundary, light and heat flow as well as import, export and storage of organic matter . Decomposers are placed in separate box to partially separate the grazing and detritus food chains. In terms of energy levels decomposers are in fact a mixed group. *Y- shaped energy flow is more realistic and practical than the single channel energy flow model because: «It conforms to the basic stratified structure of ecosystems «It separates the two chains i.e. grazing & detritus food chain in both time and space. «Micro consumers (bacteria & fungi) and the macro consumers (animals) differ greatly in size- metabolism relations in two models. FIGURE 14.16. The relationship benveen flow lofenersy through the grazing food chain aad detritus pathway (After JIT. Odum, 1956)" 3.Universal energy flow model :As the flow of energy takes place, there is gradual loss of energy at each level there by resulting in less energy available at the next tropic level as, indicated by narrower pipes (energy flow) and smaller boxes (stored energy in biomass). The loss of energy is mainly the energy which is not utilized (U). This is the energy loss in locomotion, excretion ete. or it the energy lost in respiration (CR) which is for maintenance. The remaining energy is used for production (P). 31FIGURE 14.17. Diagrammatic representation of a universal model of energy How at one tcoplt (After Eni, Odur 5 1968). i 2.1.3 ECOLOGICAL SUCCESSION Ecological Succession is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, refers to more or less predictable and orderly changes in the composition or structure of an ecological community. Succession may be initiated either by formation of new, unoccupied habitat (e.g., a lava flow or a severe landslide) or by some form of disturbance (e.g. fire, severe ‘wind throw , logging) of an existing community. Succession that begins in areas where no soil is initially present is called primary succession, whereas succession that begins in areas where soil is already present is called secondary succession Clement's theory of succession/Mechanisms of succession FE, Clement (1916) developed a descriptive theory of succession and advanced it as a general ecological concept. His theory of succession had a powerful influence on ecological thought. Clement's concept is usually termed classical ecological theory. According to Clement, succession is a process involving several phases: 1, Nudation: Succession begins with the development of a bare site, called Nudation (disturbance). Migration: It refers to arrival of propagules. Ecesis: It involves establishment and initial growth of vegetation Competition: As vegetation became well established, grew, and spread, various species began to compete for space, light and nutrients. This phase is called competition 5. Reaction: During this phase autogenic changes affect the habitat resulting in replacement of one plant community by another 6. Stabilization: Reaction phase leads to development of a climax community. BER 32Seral communities: A seral community is an intermediate stage found in an ecosystem advancing towards its climax community. In many cases more than one seral stage evolves until climax conditions are attained. A prisere is a collection of seres making up the development of an area from non-vegetated surfaces to a climax community. Depending on the substratum and climate, a seral community can be one of the following Hydrosere - Community in freshwater Lithosere Community on rock Psammosere : Community on sand ‘Xerosere Community in dry area Halosere —_ Community in saline body (e.g. a marsh) Climax community The final or stable community in a sere is the climax community or climatic vegetation. It is self- perpetuating and in equilibrium with the physical habitat. There is no net annual accumulation of organic matter in a climax community mostly. The annual production and use of energy is balanced in such a community. 2.1.4 FOOD CHAIN, FOOD WEB & ECOLOGICAL PYRAMIDS: FOOD CHAIN: In food chain each organism eats the smaller organisms and is eaten by the larger one. All those organisms which are interlinked with each other through food to gather constitute the ecosystem. +The different levels in a food chain are called tropic levels, Each food chain has three main tropic levels:- Producer level, Consumer level, and decomposer level. If any of the intermediate stage of the food chain is removed, the succeeding links of the food chain will be affected. Sample Food Chains ueremnary ‘Types of Food Chains: a) Grazing Food Chain: This type of food chain starts from living green plants goes to grazing herbivores and onto camivores. Ecosystem with such type of food chain directly 33depends upon the solar energy for their food requirements, Most of the ecosystem in nature follows this type of food chain. b) Detritus food Chain: This type of food chain goes from dead organic matter onto microorganisms and then to the organisms feeding on detritus and their predators. Such. ecosystems are less dependent on direct solar energy. ©) Parasitic Food Chain: This type of food chain starts from big hosts and ends with parasitic organisms FOOD WEB: The interconnected, interlocking pattern of food chain is known as food web. “Under natural condition of the linear arrangement of food chain hardly occurs and they remain interconnected with each other through different types of organisms at different levels Such a interconnected and interlocking pattern of food chain is known as food web & Howke and owls aB@ a snakes NK Jue] \ Tends Spiders nN a. KOE Plants ECOLOGICAL PYRAMIDS The different species in a food chain are called tropic levels. Each food chain has 3 main trophic level, producer, consumer, and decomposers. +Thus Graphical representation of these trophic levels is called as Ecological Pyramids. It was devised by an ecologist “Charles Elton” therefore this pyramid are also called Ecological pyramid or Eltonian pyramids Types of Ecological Pyramids Ecological pyramids are of three types: I 1) Pyramid of Number I)Pyramid of biomass I1)Pyramid of Energy 341) Pyramid of Number “They show the relationship between producers, herbivores, and camivores at successive tropic levels in terms of their number. «In case of pond ecosystem the producers are mainly phytoplankton and are always maximum in number this number then shows a decrease towards apex as primary consumers are zooplanktons are lesser in number than phytoplankton, the secondary consumers are large fish are even lesser in number than the phytoplankton. Thus the shape of pyramid is upright. But in case of forest ecosystem the pyramids is always inverted because the producers are mainly large trees, are lesser in numbers, the herbivores fruit eating birds are more in number than the producers, then there is gradual decrease in number of secondary consumers thus making pyramid upright again. Thus the pyramid of number does not give a true picture of the food chain and are not very functional Secondary BACTERIA, FUNGI Hyper Ssmvores ACTINONYCETES ——_|pargetes ornimary MAU Lick ano aucs — | Parasites Herbivores: ZOOPLANKTON PHYTOPLANKTON (@) UPRIGHT (©) INVERTED FIGURE 14.9, Pyramids of numbers (A) in pond ecosystem (B) in parusitic food chain. Herbivores 1) Pyramid of Biomass “The pyramid of biomass represents the relationship between different tropic levels in terms of biomass. “There is generally gradual decrease in biomass of organisms at successive levels from the producers to the top carnivores. Thus pyramid of biomass is upright for grassland ecosystem. sHowever in case of a pond as the producers are algae, are least in number and this value gradually shows an increase towards the apex of pyramid thus making the pyramid inverted in shape 35RCE res MLAS (onakos) RABBITS. RATS. A bia ‘Moweeere. jH—remveres para] Prmary consumore vy [Pam ‘raschooper) cuss apcruces a TOF co oc \preecets TIGURELAIE Pyranids ofboeass | arta (in agra te inate II) Pyramid of energy: *Of the 3 types of ecological pyramid the energy pyramid gives the best picture of overall nature of the ecosystem. In this type of pyramid the tropic level is decided depending upon the rate at which food is being produced. ‘In shape it is always upright as in most of the cases there is always gradual decrease in the energy content at successive trophic level from producers to various consumers [wsrevors | SMA 2.1.4 CLASSIFICATION OF ECOSYSTEMS Due to the abiotic factors, different ecosystems develop in different ways. These factors and their interaction between each other and with biotic components have resulted in formation of different types of ecosystems as explained below Ecosystem may be natural or artificial, Artificial Ecosystem: These are maintained or created artificially by man, The man tries to control biotic community as well as physico-chemical environment. Eg: Artificial pond, urban area development. It consists of Terrestrial and Aquatic Ecosystems which are maintained 36ECOSYSTEM he — NATURAL = — TERRESTRIAL (LAND) ES ‘AQUATIC ECOSYSTEM Grassland ecosystem ‘Marine ecosystem FRESH AQUATIC ES, MARINE AQUATIC ES ce: = a LeNTIC tone Eg: Agricultural land, artificial pond : (stagnant waters) (Running waters) URBAN AREA 8: ponds, wells, lakes eg: river streams, Different types of ecosystem of biosphere artificially categorized as follows. 1) Natural Ecosystems: These ecosystems operate by themselves under natural conditions Without any major interference by man. Based upon the particular kind of habitat, these are further divided as: «Terrestrial as forest, grassland, desert etc Aquatic which may be further distinguished as +Freshwater which may be lotic (running water as springs, stream, river) or lentic (standing water as lake, pond, pools, ditch, swamps, etc.) +Marine Ecosystems: as an ocean or shallow ones like sea or estuary ete ID) Artificial Ecosystems: These are maintained by man where, by addition of energy & planned manipulations natural balance is disturbed regularly. For eg : croplands like maize, wheat, rice-fields etc., where man tries to control the biotic community as well as physico-chemical environment are artificial ecosystems Pond Ecosystem: A Pond as a whole serves a good example of freshwater ecosystem sAbiotic Components: The chief components are heat, light, pH of water, CO2, oxygen, calcium, nitrogen, phosphates, etc. “Biotic Components: The various organization that constitute the biotic component are as follows, «Producers: These are green plants, and some photosynthetic bacteria. The producer fix radiant energy and convert it into organic substances as carbohydrates, protein etc *Macrophytes: these are large rooted plants, which include partly or completely submerged hydrophytes, eg Hydrilla, Trapha, Typha “Phytoplankton: These are minute floating or submerged lower plants eg algae +Consumers: They are heterotrophs which depend for their nutrition on the organic food manufactured by producers, «Primary Consumers: — Benthos: These are animals associated with living plants detrivores and some other microorganisms ~Zooplanktons: 37These are chiefly rotifers, protozoans, they feed on phytoplankton +Secondary Consumers: They are the Camivores which feed on herbivores, these are chiefly insect and fish, most insects & water beetles, they feed on zooplanktons. «Tertiary Consumers: These are some large fish as game fish, turtles, which feed on small fish and thus become tertiary consumers. “Decomposers: They are also known as micro- consumers. They decompose dead organic matter of both producers and animal to simple form. Thus they play an important role in the return of minerals again to the pond ecosystem, they are chiefly bacteria, & fungi. Ocean Ecosystem are more stable than pond ecosystem, they occupy 70 % of the earth surface. Abiotic Components: Dissolved oxygen, light, temperature, minerals. «Biotic Components: «Producers: These are autotrophs and are also known Primary producers. They are mainly, some ‘microscopic algae (phyto-planlanktons) besides them there are mainly, seaweeds, as brown and red algae also contribute to primary production. *Consumers: They are all heterotrophic macro consumers «Primary Consumer: The herbivores, that feed on producers are shrimps, Molluscs, fish, etc. «Secondary Consumers: These are carnivores fish as Herring, Shad, Mackerel, feeding on herbivores. «Tertiary Consumers: These includes, other camivores fishes like, COD, Halibut, Sea Turtle, Sharks etc. “Decomposers: The microbes active in the decay of dead organic matter of producers, and animals are chiefly, bacteria and some fungi pk ane Estuarine Ecosystem +An estuary is a partially enclosed body of water along the coast where fresh water from river and streams meet and mix with salt water from oceans. These Ecosystems are considered as most 38fertile ecosystem. +Abiotic Components: Nutrients such as phosphorus and nitrogen, temperature, light, salinity, pH. «This ecosystem experience wide daily and seasonal fluctuations in temperature and Salinity level because of variation in freshwater in flow. Biotic Components: «Producers: Phyplanktons- these micro-organisms manufacture food by photosynthesis and absorb nutrients such as phosphorous and nitrogen, besides them, mangroves, sea grass, weeds, and salt marshes. *Consumers: Primary consumers, Zooplanktons that feed on Phytoplankton, besides them some small microorganisms that feed on producers. «Secondary Consumer: Include worms, shellfish, small fish, feeding on Zooplanktons «Tertiary Consumer: Fishes, turtles, crabs, starfishes feeding on secondary consumers. “Decomposers: Fungi & Bacteria are the chief microbes active in decay of dead organic matter. River Ecosystem +As Compared with lentic freshwater (Ponds & lakes), lotic waters such as streams, and river have been less studied. However, the various components of an riverine and stream ecosystem can be arranged as follows. «Producers: The chief producers that remain permanently attached to a firm substratum are green algae as Cladophora, and aquatic mosses. *Consumers: The consumers show certain features as permanent attachment to firm substrata, presence of hooks & suckers, sticky undersurface, streamline bodies, flattened bodies.. Thus a variety of animal are found, which are fresh spongy and caddis-fly larvae, snails, flat worms etc. ‘Decomposers: Various bacteria and fungi like actinomycetes are present which acts as decompose 2.2 BIODIVERSITY The word biodiversity is a combination of two words: “biological and diversity” and refers to the variety of life on the Earth. Biodiversity is the degree of variation of life forms within a given species, ecosystem, biome, or an entize planet. Biodiversity is a measure of the health of ecosystems The term biological diversity was used first by wildlife scientist and conservationist Raymond F. Dasmann in the 1968. The term's contracted form biodiversity may have been coined by W.G. Rosen in 1985 Biodiversity is usually considered at three different levels: The following are different types of biodiversity 391. Genetic diversity: variety in the genetic makeup among individuals within a species 2. Species diversity: variety among the species or distinct types of living organisms found in different habitats of the planet 3. Ecosystem or ecological diversity: variety of forests, deserts, grasslands, streams, lakes, oceans, coral reefs, wetlands and other biological communities 4, Functional diversity: biological and chemical processes of functions such as energy flow an matter cycling needed for the survival of species and biological communities 1. Genetic Diversity: Genetic diversity is the “raw material” that permits species to adjust to a changing world whether these changes are due to natural factors or are caused by human factors. It refers to the variation at the level of individual genes and provides a mechanism for populations to adapt to their ever-changing environment Eg: Human beings 2. Species Diversity: Species diversity refers to the different types of living organisms on Earth. This includes the many types of birds, insects, plants, bacteria, fungi, mammals, and more. Many differing species often live together in communities depending on each other to provide their needs, A species can be defined as a group or population of similar organisms that reproduce by interbreeding within the group. Members of a species do not normally reproduce with members of any other species. Members of a specific species possess common characteristics that distinguish them from other species and this remains constant regardless of geographic location. 3. Ecosystem Diversity: Ecological diversity or ecosystem diversity is the variety of biological Communities, such as forests, deserts, grasslands and streams that interact with one another and with their physical and chemical (nonliving) environments. It relates to the different forms of life Which are present in any one particular area or site, in more precise terms, it concerns the different species of a particular genus which are present in an ecological community. 2.2.1 VALUES OF BIODIVERSITY The value of biodiversity (in terms of its commercial utility, ecological services, social and aesthetic values) is enormous. There are several ways that biodiversity and its various forms are Valuable to humans. The biodiversity value may be classified as follows: 1. CONSUMPTIVE VALUE: Biodiversity is an essential requirement for the maintenance of global food supply. The main sources of human food include animals, fish and plant produces. A large aumber of plants are consumed by human beings as food. A few animal species are consumed by people which come from cattle, pigs, sheep, goats, buffaloes, chickens, ducks, geese and turkey species. Fish: Many fiesh water fish can be grown in ponds. Israel and China already get about half of their fish from aqua culture Drugs & medicines: About 75% of the world’s population depends upon plants or plant extracts, for medicines. The drug Penicillin used as an antibiotic is derived from a fungus called Penicillium. Likewise, Tetracycline from bacteria which is used to cure malaria is obtained from the bark of cinchona tree Fuel: The fossil fuels like coal, petroleum products and natural gas are the products of biodiversity. 402. PRODUCTIVE VALUE: Some of the organisms are commercially usable where the product is marketed and sold. The animal products like tusks of elephants; musk from deer, silk from silkworm; wool from sheep or goats; fur of many animals etc all of which are taded in the market Eg: Calabar bean was tradionally used as a poison in West Africa Daisy plants were first used as a lice remedy in the Middle East and this led to the Discovery of Pyrethrum. Mosquito coils made from Pyrethrum are sold in the market. The bacterium Bacillus thuringiensis produces toxic proteins that kill certain insects 3. SOCIAL VALUE: These are the values associated with the social life, religion and spiritual aspects of the people. Many of the plants are considered to be sacred in our country like Tulasi, Mango leaves, Banana leaves . The leaves, fruits, flowers of some of the plants are used in worship. Many animals like cow, snake, bull, peacock also have significant place in spiritual and thus hold special importance. Thus, biodiversity has distinct social value, attached with different societies. 4, ETHICAL VALUE: The ethical value means that human beings may or may not use a certain species but knowing the very fact that this species exists in nature gives pleasure For eg: A peculiar species of Pigeon, grey / white bird with short legs is no more on this earth. Similarly, Dodo species is also no more. Human beings are not deriving anything direct from Kangaroo, giraffe but strongly feel that these species should exist in nature. 5. AESTHETIC VALUE: Every one of us would like to visit vast stretches of lands to enjoy the visible life. People from farther areas, spend a lot of time and money to visit wild life areas where they can enjoy the aesthetic value of biodiversity and this type of tourism is known as eco tourism. Eco-tourism is estimated to generate 12 billion dollars of revenue annually that roughly gives the aesthetic value of biodiversity. A study of the impact of environment on the psyche was undertaken by Kaplan and Kaplan (1989) in which they found that being near nature relieved working stresses while people who worked in closed environment or human made structures experienced much more job stresses and illnesses, 2.2.2 BIODIVERSITY AT GLOBAL, NATION (AL AND LOCAL LEVEL The enormous diversity of life forms in the biosphere has evolved essentially through the process of trial and error during course of organic evolution. The changes in character of living organism which confer some advantage to the species are retained. The changes in climatic conditions are reflected in the distribution of living organism and the pattern of biodiversity on our planet. The number of species present per unit area decreases as we move from mild tropics to the tundra's. The Indian region (8° to 30° N and 60° to 97.5°) with total area of 329 million hectares is very rich in biodiversity. It is estimated that about 4500 species of plants occur in this country. The position of Indian sub-continent at the confluence of there biogeography reels is also an important contributing factor and explain the preserve of Affican, European, Sind, Japanese and Indo-Malayan elements in the flora and fauna in India. It is the sum total of such remarkable adiversity that has made India a "gene bank" for a number of food crops, forest trees, medical and aromatic plants and domesticated animal. Forests are important bioreserves; most of the 1700 million hectares of tropical forests are located in poor countries. The forests surrounding Reo de Aneroid are part of vegetation which is rich in species of plants and animals that are endemic. There are about 53.5% of trees species found only in these forests and studies of birds, reptiles, primates and butter flies have revealed equally high or higher endemics 2.2.3 INDIA AS A MEGA DIVERSITY NATION India contains a great wealth of biodiversity in the forests, wet lands and marine areas. Hence biodiversity can be observed at all levels ie locally, nationally and globally . India, as a subcontinent representing a major part of South Asia is rich in flora and fauna and hence it is one of the world’s “MEGADIVERSITY NATIONS” It is estimated that over 75000 species of animals and over 45000 species of plants are found in India. Biogeographic regions of India: According to wild life Institute of India, the country has 10 distinct biogeographic zones or regions. They are 1. Trans — Himalayan Zone 2. Himalayan Zone 3. Desert Zone 4, Semi —arid Zone Western Ghats 6. Deccan Zone 7. Gangetic plain Zone 8. NE Indian Zone 9 u Coastal Zone (0. Islands around the country 2..4HOT SPOTS OF BIODIVERSITY Areas which exhibit high species richness as well as high species endemism are termed as hot spots of biodiversity. Species which are restricted only to particular areas are known as endemic. India shows a good number of endemic species. About 62% of amphibians and 50% of lizards are endemic to India, Western Ghats are the site of maximum endemism. The term “Hot spots” wwas introduced by Myers (1988). There are 25 such hot spots of biodiversity on a global level out of which two are present in India, namely the Eastern Himalayas and Western Ghats. These hotspots covering less than 2% of the world’s land area are found to have about 50% of the terrestrial biodiversity. According to Myers an area is designated as a hotspot when it contains at least 0.5% of the plant species as endemics. a) Eastern Himalayas: They display an ultra-varies topography that fosters species diversity and endemism. Recent studies have shown that North East India along with its contiguous regions of Burma and Chinese provinces of Yunnan and Schezwan is an active center of organic evolution and is considered to be the cradle of flowering plants. Out of the world’s recorded flora 30% are endemic to India of which 35000 are in the Himalayas. 42b) Western Ghats: It extends along a 17000 km® strip of forests in Maharashtra, Kamataka, Tamilnadu and Kerala and has 40% of the total endemic plant species. The major centers of diversity are Agastyamalai Hills and Silent valley- the new Amambalam Reserve Basin It is reported that only 6.8% of the original forests are existing today while the rest has been deforested or degraded, which raises a serious cause of alarm, because it means we have already lost a huge proportion of the biodiversity 2.2.5 THREATS TO BIODIVERSITY Extinction or elimination of a species is a natural process of evolution. In the geologic period the earth has experienced mass extinctions. During evolution, species have died out and have been replaced by others. However, the rate of loss of species in geologic past has been a slow process, keeping in view the vast span of time going back to 444 million years. The process of extinction has become particularly fast in the recent years of civilization. Edward O. Wilson prefers the acronym HIPPO, standing for habitat destruction, invasive species, pollution, human overpopulation, and over-harvesting Following are the major causes and issues related to threats to biodiversity. 1. Habitat destruction: Habitat destruction has played a key role in extinctions, especially related to tropical forest destruction, Factors contributing to habitat loss are: overpopulation, deforestation, pollution (air pollution, water pollution, soil contamination) and global warming or climate change Habitat size and numbers of species are systematically related. Physically larger species and those living at lower latitudes or in forests or oceans are more sensitive to reduction in habitat area. Conversion to "trivial" standardized ecosystems (¢.g., monoculture following deforestation) effectively destroys habitat for the more diverse species that preceded the conversion. In some countries lack of property rights or lax law/regulatory enforcement necessarily leads to biodiversity loss (degradation costs having to be supported by the community) 2. Poaching: Ilegal trade of wildlife products by killing prohibited endangered animals ic. poaching is another threat to wildlife. Despite international ban on trade in products from endangered species, smuggling of wildlife items like furs, hides, hors, tusks, live specimens and herbal products worth millions of dollars per year continues, the developing nations in Asia, Latin America and Africa are the richest source of biodiversity and have enormous wealth of wildlife. The rich countries in Europe and North America and some affluent countries in Asia like Japan, Taiwan and Hong Kong are the major importers of the wildlife products or wildlife itself. The trading of such wild life products is highly profit making for the poachers who just hnunt these prohibited wild lives and smuggle it to other countries mediated through mafia. The worst part is that for every live animal that actually gets into the market about 50 additional animals are caught and killed If you are fond of rare plants, fish or birds, please make sure that you are not going to the endangered species or wild-caught species. Doing so will help in checking further decline of these species. Also do not purchase fur coat, purse or bag, or items made of crocodile skin or python skin. You will certainly help in preserving biodiversity by doing so. 433, Man-Wildlife Conflicts: We have discussed about the need to preserve and protect wildlife. However, sometimes we come across conflicting situations when wildlife starts causing immense damage and danger to man and under such conditions it becomes very difficult for the forest department to pacify the affected villages and gain local support for wildlife conservation. Instances of man animal conflicts keep on coming to lime light from several states in our country. In Sambalpur, Orissa 195 humans were killed in the last Syears by elephants. In retaliation the villagers killed 95 elephants in the border region of Kote-Chamarajanagar belt in Mysore have been reported recently. The man-elephant conflict in this region has arisen because of massive damage done by the elephants to the farmer's cotton and sugarcane crops. The agonized villagers electrocute the elephants and sometimes hide explosives in the sugarcane fields, which explode as the elephants intrude into their fields. In fact, more killings are done by locals than by poachers. Causes of Man-animal conflicts: Dwindling habitats of tigers, elephants, shinos and bears due to shrinking forests cover are compelled to move outside the forests and attack the field or sometimes even humans, Human encroachment into the forest areas has rendered all forest living animals to trespass the borders of human civilizations. This is because the conflicts between man and the wildlife have increased. since it is an issue of survival of both 3.1 Invasive Non-Native Species: Species that are non-native to a particular area can sometimes spread very quickly, for example the zebra mussel and Japanese knotweed have spread rapidly in Ireland in the past two decades. As a result, these species can destabilize an ecosystem by altering habitats affecting food webs. 3.2 Pollution/Litter: As you will remember from the Litter and Waste theme, pollution is always caused by humans. Pollution can have a huge impact, altering the balance within ecosystems, and is the cause of death for millions of animals and plants around the world every year. 3.3 Land Use Change/Increased Infrastructure Development: This is the alteration of natural areas by humans, for example, the clearing of huge areas of rainforest in South America for farming. In Ireland, upland open habitats, such as rough grassland, scrub and heath, have been changed by agriculture and afforestation. 3.4 Intensive Farming Practices: Extensive use and concentrations of chemical and/or iological pesticides and the removal of hedgerows are typical practices in modem-day intensive farming. Often large areas of land are planted with a single crop (monocultures) which greatly reduces the level of biodiversity in that area 3.5 Climate Change: It is now widely accepted that the current global rate of change in climate is as a result of human activity. As global air or sea temperature changes, even by just 1 or 2 degrees, the habitats in which species live will also change and may even become uninhabitable to some species 442.2.6 ENDANGERED AND ENDEMIC SPECIES Endangered species A species whose numbers are reduced to the point. That means endangered species are in immediate danger of extinction The International Union Conservation of Nature ( IUCN ) classified the species of plants and animals as (a) Endangered species (b) Threatened species: Species ( including animals, plants, fungi, ete.) which are vulnerable to endangerment in the near future) (©) Rare species : Among the important endangered animal species, Indian wild ass; the Kashmir stag, the Golden Langur etc .. are considered highly endangered. There are also endangered bird species like Siberian crane; the great Indian Bustard; the florican etc The IUCN published the data on endangered species of both plants and animals of India. The data symbolizes the working signal for those species which are endangered and if not protected are likely to become extinct in near future A species is said to be extinct when it is not seen in the wild for 50 years at a stretch e.g. Dodo, Passenger Pigeon. A species is said to be endangered when its number has been reduced to a critical level or whose habitat, have been drastically reduced and if such species is not protected and conserved, it is in immediate danger of extinction Endangered species of India The International Union for Conservation of Nature and Natural Resources(IUCN) publishes the Red Data Book which include the list of endangered species of plants and animals. The red data symbolizes the waming signal for those species which are endangered and if not protected are likely to become extinct in near future The animals that are listed under the critically endangered category are as under 1)MalabarLargeSpottedCivet 2)NamdaphaFlyingSquirrel 3)SalimAli'sFruitBat 4)SumatranRhinoceros EndangeredSpeciesareasunder: 1)AsiaticLion 2)AsiaticBlackBear 3)DesertCat 4)GreatIndianRhinoceros 5)IndianElephant(or)A sianElephant ThreatenedSpeciesareasunder: 1)IndianWildAss 2)Leopard 45Endemic species of India India has two biodiversity hot-spots and thus possesses a large number of endemic species. The endemic species are those taxa whose distribution is confined to a restricted area due to their specific ecological niches and edaphic gradients. Therefore, the habitats of endemic species are far more vulnerable than other species. Endemic species once lost, it is a loss of biodiversity of these species forever. In India there are about 5725 endemic taxa of angiosperms (33.5% of Indian flora) which are located in 25 hot spots. The major hotspots in India which contain largest number of endemic plant species are the Southem Western Ghats and Eastern Himalayas with 1286 and 1808 endemic species respectively. There are about 1272 species of endemic angiosperms out of 3800 species occurring in Kerala (33.5% of Kerala flora) which represent 22.6% of Indian endemics Seventy percent of the 1272 species of endemics have the major areas of distribution in Kerala with spill over in adjacent regions. On the basis of the study of the distributional range, about 102 endemic species occur exclusively in Kerala. A large number out of a total of 81,000 of animals in our country is endemic. The Western Ghats, are particularly rich in amphibians (frogs, toads etc) and reptiles (lizards, crocodiles etc) about 62% amphibians and 50% lizards are endemic to Western Ghats, 2.2.1 CONSERVATION OF BIODIVERSITY In order to maintain and conserve biodiversity, the Ministry of Environment and Forests, government of India has already taken several steps to manage wildlife, the objectives of which are 1, Maintenance of a number of species in protected areas such as National Parks, Sanctuaries, 2. To improve the biosphere reserves 3. Implement strict restrictions of export of rare plants and animals 4, Educate the public on these through the government agencies and NGO's, Seo In sity ex site ——_Tr—1 Protected Area Network Plants Field gene banks gardens Home Cryopreservation Arborat gardens: Zoologica! gardens Sacred Biosphere National parks faquaris Sacred takes sanctuaries 46A) In-situ conservation: The preservation of species in its natural ecosystem is called in-situ conservation. As a consequence, protected areas are being identified and maintained for natural conservation of species by individual countries. For the conservation and management of endangered species several projects have been established. These are Tiger Projects: Corbett National Park which is 300 km from New Delhi is the oldest National Park of India having 1318.54 sq km. It was one of the nine Tiger Reserves created at the launch of the Project Tiger in 1973. Gir Lion Projects: The Gir Forest of Gujarat where lions are found. This has an area of 1412 sq kans and declared as a National Park. Elephant Projects: The objective was to ensure long-term survival of population of elephants (aot come into operations). Project Elephant (PE), a centrally sponsored scheme, was launched in February 1992 to provide financial and technical support to major elephant bearing States in the country for protection of elephants and their habitats. The Project is being implemented in 13 StatevUTs, viz..Andhra Pradesh, Arunachal Pradesh, Assam, Jharkhand, Kamataka, Kerala, Meghalaya, Nagaland, Orissa, Tamil Nadu, Uttaranchal, Uttar Pradesh and West Bengal. There are about 7000 protected areas in the world which include a variety of National parks, Sanctuaries etc which vary in size (between 100 to 500 sq km), purpose (protection of one or more species and their habitats). In India, there are 39 National Parks and 492 wildlife sanctuaries. National Parks: These are protected areas exclusively for wild life. Human activities like hunting, Firewood collection, timber harvesting etc... are restricted in these areas to that wild plants and animals could grow in a protected environment The following measures should be adopted for the conservation of biodiversity: 1. Over grazing in the forest and areas of vegetation should be controlled because it may Destroy the useful rare plants The habitat of plants and animals should be conserved. The natural condition of ecosystem should be studied and researched in time and again, then Specific programs for conservation should be conducted Human activities should be done without destroying natural environment. Illegal hunting and smuggling of animals and plants should be strictly avoided Effective laws and rules should be adopted for the conservation of rare animals and plants. Industries are established from the raw materials. During the process of collecting raw materials, care should be taken not to destroy useful plants and habitats of animals 8, Public awareness should be created about the importance of rare animals and plants, causes of rareness and measures for their preservation Aas B) Ex-situ conservation: The conservation of elements of biodiversity out of the context of their natural habitats is referred to as ex-situ conservation. Zoos, botanical gardens and seed banks are all example of ex-situ conservation. In India we have the following important gene and seed bank facilities a7National Bureau of Plant Genetic Resources (NBPGR) is located in New Delhi. Here agricultural and horticultural crops are stored by cryopreservation of seeds, pollens etc. by using liquid nitrogen at a low temperature as low as -196°e. National Bureau of Animal Genetic Resources (NBAGR) located at kamal, Haryana It preserves the semen of domesticated bovine animals. 48,