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UNIT II ECOLOGY

Ecology is the systematic study of communications among and their environment, such as the communications organisms have with each other and with their abiotic environment. Topics of importance to ecologists include the variety, distribution, amount (), number (population) of organisms, as well as competition between them within and among ecosystems. Ecosystems are composed of dynamically interacting parts including organisms, the communities they make up, and the non-living components of their environment. Ecosystem procedures, such as primary production, pedogenesis, nutrient cycling, and various niche construction activities, regulate the flux of energy and matter through an environment. These procedures are sustained by organisms with specific history traits, and the variety of organisms is called biovariety. Biovariety, which refers to the varieties of species, genes, and ecosystems, enhances certain ecosystem services. Ecology is an interdisciplinary field that includes biology and science. Ancient Greek philosophers such as Hippocrates and Aristotle laid the foundations of ecology in their studies on natural history. Modern ecology transformed into a more rigorous science in the late 19th century. Evolutionary theories of adaptation and natural selection became cornerstones of modern ecological theory. Ecology is not synonymous with environment, environmentalism, natural history, or ecological science. It is closely related to evolutionary biology, genetics, and ethology. An understanding of how affects the ecological function is an important focus area in ecological studies. Ecologists seek to explain:  Life procedures, communications and adaptations  The movement of materials and energy through living communities  The successional development of ecosystems, and  The abundance and distribution of organisms and biovariety in the context of the environment.

Ecology is a human science as well. There are many practical applications of ecology in conservation biology, wetland management, natural resource management (Agroecology, agriculture, forestry, Agroforestry, fisheries), city planning (urban ecology), community health, economics, basic and applied

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E-CONTENT COMPILED AND DESIGNED BY SABA KHANAM science, and human social interaction (human ecology). Organisms and resources compose ecosystems which, in turn, maintain biophysical feedback mechanisms that moderate procedures acting on living (biotic) and nonliving (abiotic) components of the planet. Ecosystems sustain life-supporting functions and produce natural capital like biomass production (food, fuel, fiber and medicine), the regulation of climate, global biogeochemical cycles, water filtration, formation, erosion control, flood protection and many other natural features of systematic, historical, economic, or intrinsic value.

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GEOBIOCHEMICAL CYCLES: CARBON, NITROGEN, OXYGEN AND PHOSPHORUS CYCLES

The living world depends upon the flow of energy and the circulation of nutrients through ecosystem. Both influence the abundance of organisms, the metabolic rate at which they live, and the complexity of the ecosystem. You have already read in previous sections that energy flows through ecosystems enabling the organisms to perform various kinds of work and is ultimately lost as heat forever in terms of the usefulness of the system. On the other hand, nutrients of food matter never get completely used up. They can be recycled again and again indefinitely. This becomes more clear when we say that when we breathe we may be inhaling several million atoms of elernents that may have been inhaled by the Ernperor Jahangir or any other person from history. Nutrients that are needed by organislns in large amounts are called macronutrients while those, which are needed in traces are called micronutrients

WATER CYCLE (HYDROLOGIC CYCLE)

Water is one of the most important substances for life. On an average water constitutes 70% of the body weight of an . It is one of the important ecological factors, which determines thc structllre and function of the ecosystem. Cycling of all other elements is also dependent upon water as it provides their transportation during tlie various steps and it also is a solvent medium for their uptake by organisms. Water covers about 75% of the earth's surface, occurrinig in lakes, rivers, seas and oceans. The oceans alone contain 97% of all the water on earth. Much of this remainder is frozen in the polar ice and glaciers. Less than loh water is present in the form of ice free fresh water in rivers, lakes, and aquifers. Yet this relatively negligible portion of the planet's water is crucially important to all forms of terrestrial and aquatic life. There is also underground supply of water. near tlie surface also serve as reservoir for enormous quantities of water.

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THE

Ground water 0.62 Lakes (fresh water) 0.009 inland sea, saline lakes 0.008 Soil moisture 0.005 Atmosphere 0.001 Rivers and stream 0.0001 1 Carbon is present in the atmosphere, mainily in the form of carbon dioxide (CO2). It is a minor constituent of the atmosphere as compared to oxygen and nitrogen. However, as you are well aware without carbon dioxide life could not exist, for it is vital to the production of carbohydrates through photosynthesis by and is the building block of life. It is the element that anchors all organic substances from and oil to DNA (deoxyribonucleic acid, the compound that carries genetic information). Carbon is returned to the environment almost as fast as it is removed. Figure 18.3 illustrates the global carbon cycle. Carbon from the atmospheric pool moves to green plants, and then to . Finally, from them directly to the atmosphere by process of respiration at various trophic levels in the food chain or to bacteria, fungi and other micro-organisms that return it to atmosphere through decomposition of dead organic matter. Some carbon however enters a long term cycle. It may accumulate as undecomposed organic matter as in the peaty layers of bogs and moorlands or as insoluble carbonates (for example the insoluble calcium carbonate (CaC03) of various sea shells), which accumulate in bottom in aquatic systems. This sedimentary carbon eventually turns into sedimentary rocks such as and dolomite and may take a long time to be released. In deep oceans such carbon can remain buried for millions of years till geological movement may lift these rocks above sea level. These rocks may be exposed to erosion, releasing their carbon dioxide and carbonates and bicarbonates into steams and rivers: hard water has usually flowed through lime stone at some point, picking up carbonates which they accumulate as 'fur' in kettles when the water is boiled. Fossil fuels such as , oil and natural gas etc. are also part of the carbon cycle, which may release their carbon compounds after several years. These fossil fuels are organic compounds that were buried before they could be decomposed and were subsequently transformed by time and geological processes into fossil fuels. When fossil fuels are burned the carbon stored in them is released back into the atmosphere as carbon-dioxide. In. summary carbon is sequestered by plants on land and in oceans through photosynthesis by using sunlight. Leaving few exceptions every living thing competes to harvest some of that carbon and include it into a form specified by its own DNA. After death and decay of organism most of the carbon is oxidized and used by other living organisms, in the carbon cycle. A very small quantity escapes oxidation, is buried, and through geological time may be transformed into hydrocarbons such as coal and oil. Today when we burn coal (Fig. 18.3) in fact we are releasing carbon (in the form Of COz) that may once

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E-CONTENT COMPILED AND DESIGNED BY SABA KHANAM have been part of DNA of a dinosaur and this time it can become a part of your cell. Carbon cycle (Fig. 18.4) basically involves a continuous exchange of carbon dioxide between the atmosphere and organisms on one hand, and between the atmosphere and the sea, on the other. The immediate source of carbon dioxide for exchange in the oceans is restricted to surface layers of water.

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NITROGEN CYCLE

The Another critical element in is Nitrogen (N2). Nitrogen is an essential constituent of protein which is a building block of all living tissue. It constitutes nearly 16% by weight of all the proteins. There is an inexhaustible supply of nitrogen in the atmosphere but the elemental form cannot be used directly by most of the living organisms.

Nitrogen needs to be 'fixed', that is, converted to ammonia, nitrites or nitrates, before it can be taken up by plants. on earth is accomplished in three different ways: i) by certain free-living and symbiotic bacteria and blue green ii) ii) by man using industrial processes (fertilizer factories) and

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iii) iii) To a limited extent by atmospheric phenomena such as thunder and lighting. At present, the amount fixed by man industrially far exceeds the amount fixed by biological and atmospheric actions. Most of the usable nitrogen for earth's ecosystem is through nitrogen fixation by microorganism.

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OXYGEN CYCLE , along with the carbon cycle and nitrogen cycle plays an essential role in the existence of life on the earth. The oxygen cycle is a biological process which helps in maintaining the oxygen level by moving through three main spheres of the earth which are:

 Atmosphere  Lithosphere  . This explains the movement of oxygen gas within the atmosphere, the ecosystem, biosphere and the lithosphere. The oxygen cycle is interconnected with the carbon cycle. The atmosphere is the layer of gases presents above the earth’s surface. The sum of all Earth’s ecosystem makes a biosphere. Lithosphere, which is the solid outer section along with the Earth’s crust and it is the largest reservoir of oxygen.

Stages of the Oxygen Cycle The steps involved in the oxygen cycle are: Stage-1: All green plants during the process of photosynthesis, release oxygen back into the atmosphere as a by-product.

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Stage-2: All aerobic organisms use free oxygen for respiration. Stage-3: Animals exhale Carbon dioxide back into the atmosphere which is again used by the plants during photosynthesis. Now oxygen is balanced within the atmosphere. The four main processes that use Atmospheric oxygen are: Breathing – It is the physical process, through which all living organisms including plants, animals, and humans inhale oxygen from the outside environment into the cells of an organism and exhale carbon dioxide back into the atmosphere. Decomposition: It is one of the natural and most important processes in the oxygen cycle and occurs when an organism dies. The dead or plants decay into the ground, and the organic matter along with the carbon, oxygen, water and other components are returned back into the soil and air. This process is carried out by the invertebrates including fungi, bacteria and some insects which are collectively called as the decomposers. The entire process requires oxygen and releases carbon dioxide. Combustion: It is also one of the most important processes which occur when any of the organic materials including fossil fuels, plastics and , are burned in the presence of oxygen and releases carbon dioxide into the atmosphere. Rusting: This process also requires oxygen. It is the formation of oxides which is also called oxidation. In this process, metals like iron or alloy rust when they are exposed to moisture and oxygen for an extended period of time and new compounds of oxides are formed by the combination of oxygen with the metal.

Importance of Oxygen Cycle As we all know, Oxygen is one of the most essential components of the Earth’s atmosphere. It is mainly required for:

 Breathing  Combustion  Supports aquatic life  Decomposition of organic waste. Oxygen is an important element required for life; however, it can be toxic to some anaerobic bacteria (especially obligate anaerobes). The oxygen cycle is mainly involved in maintaining the level of oxygen in the atmosphere. The entire cycle can be summarized as, the oxygen cycle begins with

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E-CONTENT COMPILED AND DESIGNED BY SABA KHANAM the process of photosynthesis in the presence of sunlight, releases oxygen back into the atmosphere, which humans and animals breathe in oxygen and breathe out carbon dioxide, and again linking back to the plants. This also proves that both the oxygen and carbon cycle occur independently and are interconnected to each other.

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PHOSPHORUS CYCLE

Phosphorus is an important element for all forms of life. As phosphate (PO4), it makes up an important part of the structural framework that holds DNA and RNA together. Phosphates are also a critical component of ATP— the cellular energy carrier—as they serve as an energy ?release’ for organisms to use in building proteins or contacting muscles. Like calcium, phosphorus is important to vertebrates; in the human body, 80% of phosphorous is found in teeth and bones.

The differs from the other major biogeochemical cycles in that it does not include a gas phase; although small amounts of phosphoric acid (H3PO4) may make their way into the atmosphere, contributing—in some cases—to . The water, carbon, nitrogen and sulfur cycles all include at least one phase in which the element is in its gaseous state. Very little phosphorus circulates in the atmosphere because at Earth’s normal temperatures and pressures, phosphorus and its various compounds are not gases. The largest reservoir of phosphorus is in sedimentary rock.

It is in these rocks where the phosphorus cycle begins. When it rains, phosphates are removed from the rocks (via weathering) and are distributed throughout both soils and water. Plants take up the phosphate ions from the soil. The phosphates then moves from plants to animals when herbivores eat plants and carnivores eat plants or herbivores. The phosphates absorbed by animal tissue through consumption eventually returns to the soil through the excretion of urine and feces, as well as from the final decomposition of plants and animals after death. The same process occurs within the aquatic ecosystem. Phosphorus is not highly soluble, binding tightly to molecules in soil, therefore it mostly reaches waters by traveling with runoff soil particles. Phosphates also enter waterways through fertilizer runoff, sewage seepage, natural deposits, and wastes from other industrial processes. These phosphates tend to settle on ocean floors and lake bottoms. As sediments are stirred up, phosphates may reenter the phosphorus cycle, but they are more commonly made available to aquatic organisms by being exposed through erosion. Water plants take up the waterborne phosphate which then travels up through successive stages of the aquatic food chain.

While obviously beneficial for many biological processes, in surface waters an excessive concentration of phosphorus is considered a pollutant. Phosphate

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E-CONTENT COMPILED AND DESIGNED BY SABA KHANAM stimulates the growth of plankton and plants, favoring weedy species over others. Excess growth of these plants tend to consume large amounts of dissolved oxygen, potentially suffocating fish and other marine animals, while also blocking available sunlight to bottom dwelling species. This is known as eutrophication.

Humans can alter the phosphorus cycle in many ways, including in the cutting of tropical rain forests and through the use of agricultural fertilizers. Rainforest ecosystems are supported primarily through the recycling of nutrients, with little or no nutrient reserves in their soils. As the forest is cut and/or burned, nutrients originally stored in plants and rocks are quickly washed away by heavy rains, causing the land to become unproductive. Agricultural runoff provides much of the phosphate found in waterways. Crops often cannot absorb all of the fertilizer in the soils, causing excess fertilizer runoff and increasing phosphate levels in rivers and other bodies of water. At one time the use of laundry detergents contributed to significant concentrations of phosphates in rivers, lakes, and streams, but most detergents no longer include phosphorus as an ingredient.

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ECOSYSTEM

An ecosystem consists of the biological community that occurs in some locale, and the physical and chemical factors that make up its non-living or abiotic environment. There are many examples of ecosystems -- a pond, a forest, an estuary, a grassland. The boundaries are not fixed in any objective way, although sometimes they seem obvious, as with the shoreline of a small pond. Usually the boundaries of an ecosystem are chosen for practical reasons having to do with the goals of the particular study.

The study of ecosystems mainly consists of the study of certain processes that link the living, or biotic, components to the non-living, or abiotic, components. The two main processes that ecosystem scientists study are Energy transformations and biogeochemical cycling. As we learned earlier, ecology generally is defined as the interactions of organisms with one another and with the environment in which they occur. We can study ecology at the level of the individual, the population, the community, and the ecosystem.

Studies of individuals are concerned mostly about physiology, reproduction, development or behavior, and studies of populations usually focus on the habitat and resource needs of particular species, their group behaviors, population growth, and what limits their abundance or causes extinction. Studies of communities examine how populations of many species interact with one another, such as predators and their prey, or competitors that share common needs or resources.

In ecosystem ecology we put all of this together and, insofar as we can, we try to understand how the system operates as a whole. This means that, rather than worrying mainly about particular species, we try to focus on major functional aspects of the system. These functional aspects include such things as the amount of energy that is produced by photosynthesis, how energy or materials flow along the many steps in a food chain, or what controls the rate of decomposition of materials or the rate at which nutrients (required for the production of new organic matter) are recycled in the system.

Components of an Ecosystem You are already familiar with the parts of an ecosystem. From this course and from general knowledge, you also have a basic understanding of the diversity of plants and animals, and how plants and animals and microbes obtain water, nutrients, and food. We can clarify the parts of an

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E-CONTENT COMPILED AND DESIGNED BY SABA KHANAM ecosystem by listing them under the headings "abiotic" and "biotic".

ABIOTIC COMPONENTS BIOTIC COMPONENTS

Sunlight Primary producers

Temperature Herbivores

Precipitation Carnivores

Water or moisture Omnivores

Soil or water chemistry (e.g., P, NO3, NH4) Detritivores etc. etc.

All of these vary over space/time

By and large, this set of components and environmental factors is important almost everywhere, in all ecosystems.

Usually, biological communities include the "functional groupings" shown above. A functional group is a biological category composed of organisms that perform mostly the same kind of function in the system; for example, all the photosynthetic plants or primary producers form a functional group. Membership in the functional group does not depend very much on who the actual players (species) happen to be, only on what function they perform in the ecosystem.

Processes of Ecosystems This figure with the plants, zebra, lion, and so forth, illustrates the two main ideas about how ecosystems function: ecosystems have energy flows and ecosystems cycle materials. These two processes are linked, but they are not quite the same (see Figure 1).

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Figure 1. Energy flows and material cycles.

Energy enters the biological system as light energy, or photons, is transformed into chemical energy in organic molecules by cellular processes including photosynthesis and respiration, and ultimately is converted to heat energy. This energy is dissipated, meaning it is lost to the system as heat; once it is lost it cannot be recycled. Without the continued input of solar energy, biological systems would quickly shut down. Thus the Earth is an open system with respect to energy.

Elements such as carbon, nitrogen, or phosphorus enter living organisms in a variety of ways. Plants obtain elements from the surrounding atmosphere, water, or soils. Animals may also obtain elements directly from the physical environment, but usually they obtain these mainly as a consequence of consuming other organisms. These materials are transformed biochemically within the bodies of organisms, but sooner or later, due to excretion or decomposition, they are returned to an inorganic state (that is, inorganic material such as carbon, nitrogen, and phosphorus, instead of those elements being bound up in organic matter). Often bacteria complete this process, through the process called decomposition or mineralization (see next lecture on microbes).

During decomposition these materials are not destroyed or lost, so the Earth is a closed system with respect to elements (with the exception of a meteorite entering the system now and then...). The elements are cycled endlessly between

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E-CONTENT COMPILED AND DESIGNED BY SABA KHANAM their biotic and abiotic states within ecosystems. Those elements whose supply tends to limit biological activity are called nutrients.

BIOME

A biome is an area of the planet that can be classified according to the plants and animals that live in it. Temperature, soil, and the amount of light and water help determine what life exists in a biome.

A biome is different from an ecosystem. An ecosystem is the interaction of living and nonliving things in an environment. A biome is a specific geographic area notable for the species living there. A biome can be made up of many ecosystems. For example, an aquatic biome can contain ecosystems such as coral reefs and kelp forests.

Not all scientists classify biomes in the same way. Some use broad classifications and count as few as six biomes. These are forest, grassland, freshwater, marine, desert, and tundra.

Other scientists use more precise classifications and list dozens of different biomes. For example, they consider different kinds of forests to be different biomes. Tropical rain forests that are warm and wet year-round are one biome. Temperate deciduous forests—those that have cold winters, warm summers, and are dominated by trees that lose their leaves—are a different biome. Taiga forests, which are in cold regions and are dominated by cone-bearing firs and spruces, are yet another biome.

Boundaries between biomes are not always sharply defined. For instance, there are sometimes transition zones between grassland and forest biomes. Coasts and wetlands are transition zones between terrestrial and aquatic biomes.

Biomes move as the climate changes. Ten thousand years ago, parts of North Africa were lush landscapes cut by flowing rivers. Hippopotamuses, giraffes, and crocodiles lived amid abundant trees. Gradually, the climate dried out. Today, this region is part of the Sahara Desert, the world's largest desert.

BIOMASS

Biomass is renewable energy from plants and animals

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Biomass is organic material that comes from plants and animals, and it is a renewable source of energy.

Biomass contains stored energy from the sun. Plants absorb the sun's energy in a process called photosynthesis. When biomass is burned, the chemical energy in biomass is released as heat. Biomass can be burned directly or converted to liquid biofuels or biogas that can be burned as fuels.

Examples of biomass and their uses for energy  Wood and wood processing wastes—burned to heat buildings, to produce process heat in industry, and to generate electricity  Agricultural crops and waste materials—burned as a fuel or converted to liquid biofuels  Food, yard, and wood waste in garbage—burned to generate electricity in power plants or converted to biogas in landfills  Animal manure and human sewage—converted to biogas, which can be burned as a fuel

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BIODIVERSITY

Biodiversity, also called biological diversity, the variety of life found in a place on Earth or, often, the total variety of life on Earth. A common measure of this variety, called species richness, is the count of species in an area. Colombia and Kenya, for example, each have more than 1,000 breeding species of birds, whereas the forests of Great Britain and of eastern North America are home to fewer than 200. A coral reef off northern Australia may have 500 species of fish, while the rocky shoreline of Japan may be home to only 100 species. Such numbers capture some of the differences between places—the tropics, for example, have more biodiversity than temperate regions—but raw species count is not the only measure of diversity. Furthermore, biodiversity encompasses the genetic variety within each species and the variety of ecosystems that species create.

Biodiversity is the variety and variability of life on Earth. Biodiversity is typically a measure of variation at the genetic, species, and ecosystem level. Terrestrial biodiversity is usually greater near the equator, which is the result of the warm climate and high primary productivity. Biodiversity is not distributed evenly on Earth, and is richest in the tropics. These tropical forest ecosystems cover less than 10 percent of earth's surface, and contain about 90 percent of the world's species. Marine biodiversity is usually highest along coasts in the Western Pacific, where sea surface temperature is highest, and in the mid-latitudinal band in all oceans. There are latitudinal gradients in species diversity. Biodiversity generally tends to cluster in hotspots, and has been increasing through time, but will be likely to slow in the future.

BIODIVERSITY DEPLETION

Rapid environmental changes typically cause mass extinctions. More than 99.9 percent of all species that ever lived on Earth, amounting to over five billion species, are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, of which about 1.2 million have been documented and over 86 percent have not yet been described. More recently, in May 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one-thousandth of one percent described. The total amount of

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E-CONTENT COMPILED AND DESIGNED BY SABA KHANAM related DNA base pairs on Earth is estimated at 5.0 x 1037 and weighs 50 billion tonnes. In comparison, the total mass of the biosphere has been estimated to be as much as 4 TtC (trillion tons of carbon). In July 2016, scientists reported identifying a set of 355 genes from the Last Universal Common Ancestor (LUCA) of all organisms living on Earth.

The age of the Earth is about 4.54 billion years. The earliest undisputed evidence of life on Earth dates at least from 3.5 billion years ago, during the Eoarchean Era after a geological crust started to solidify following the earlier molten Hadean Eon. There are microbial mat fossils found in 3.48 billion-year-old sandstone discovered in Western Australia. Other early physical evidence of a biogenic substance is graphite in 3.7 billion-year-old meta-sedimentary rocks discovered in Western Greenland. More recently, in 2015, "remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia. According to one of the researchers, "If life arose relatively quickly on Earth .. then it could be common in the universe."

HOTSPOTS

A biodiversity hotspot is a region with a high level of endemic species that have experienced great habitat loss.[69] The term hotspot was introduced in 1988 by Norman Myers.[70][71][72][73] While hotspots are spread all over the world, the majority are forest areas and most are located in the tropics.

Brazil's Atlantic Forest is considered one such hotspot, containing roughly 20,000 species, 1,350 vertebrates and millions of insects, about half of which occur nowhere else.[74][citation needed] The island of Madagascar and India are also particularly notable. Colombia is characterized by high biodiversity, with the highest rate of species by area unit worldwide and it has the largest number of endemics (species that are not found naturally anywhere else) of any country. About 10% of the species of the Earth can be found in Colombia, including over 1,900 species of bird, more than in Europe and North America combined, Colombia has 10% of the world's mammals species, 14% of the amphibian species and 18% of the bird species of the world. Madagascar dry deciduous forests and lowland rainforests possess a high ratio of endemism. Since the island separated from mainland Africa 66 million years ago, many species and ecosystems have

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E-CONTENT COMPILED AND DESIGNED BY SABA KHANAM evolved independently. Indonesia's 17,000 islands cover 735,355 square miles (1,904,560 km2) and contain 10% of the world's flowering plants, 12% of mammals and 17% of reptiles, amphibians and birds—along with nearly 240 million people. Many regions of high biodiversity and/or endemism arise from specialized habitats which require unusual adaptations, for example, alpine environments in high mountains, or Northern European peat bogs.

Accurately measuring differences in biodiversity can be difficult. Selection bias amongst researchers may contribute to biased empirical research for modern estimates of biodiversity. In 1768, Rev. Gilbert White succinctly observed of his Selborne, Hampshire "all nature is so full, that that district produces the most variety which is the most examined."

OBJECTIVES AND ADVANTAGES OF BIODIVERSITY CONSERVATION

Conservation of biological diversity leads to conservation of essential ecological diversity to preserve the continuity of food chains.

The genetic diversity of plants and animals is preserved.

It ensures the sustainable utilisation of life support systems on earth.

It provides a vast knowledge of potential use to the scientific community.

A reservoir of wild animals and plants is preserved, thus enabling them to be introduced, if need be, in the surrounding areas.

Biological diversity provides immediate benefits to the society such as recreation and tourism.

Biodiversity conservation serves as an insurance policy for the future.

TYPES OF CONSERVATION

Ex situ conservation

Conserving biodiversity outside the areas where they naturally occur is known as ex situ conservation. Here, animals and plants are reared or cultivated in areas like zoological or botanical parks.

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Reintroduction of an animal or plant into the habitat from where it has become extinct is another form of ex situ conservation. For example, the Gangetic gharial has been reintroduced in the rivers of Uttar Pradesh, Madhya Pradesh and Rajasthan where it had become extinct.

Seedbanks, botanical, horticultural and recreational gardens are important centres for ex situ conservation.

In situ conservation

Conserving the animals and plants in their natural habitats is known as in situ conservation. This includes the establishment of

 National parks and sanctuaries  Biosphere reserves  Nature reserves  Reserved and protected forests  Preservation plots  Reserved forests

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