Environmental Awareness and Disaster Management PDF

UNIT – 1 NATURAL RESOURSCES & ASSOCITED PROBLEMS Objectives After going through this unit, you will be able to: Explain the meaning of natural resources Discuss the importance of natural resources Elucidate natural resources and our planet Discuss the reasons for the exploitation of natural resources Elucidate the need for conserving natural resources Structure 1.1 Meaning of Natural Resources 1.1.1 Land 1.1.2 Water 1.1.3 Food 1.1.4 Forests 1.1.5 Mineral and Energy 1.2 Importance of Natural Resources 1.2.1 Natural Resources and Our Planet 1.2.2 Exploitation of Natural Resources 1.2.3 Reasons for Exploitation 1.2.4 Burden of Overpopulation on Natural Resources 1.2.5 Burden of Industrialisation on Natural Resources 1.2.6 Conservation of Natural Resources 1.2.7 Need for Conserving Natural Resources 1.2.8 Methods of Conserving Natural Resources 1.3 Summary 1.4 Keywords 1.1 MEANING OF NATURAL RESOURCES Since the origin of human history, man has used natural resources provided by Mother Earth for his consumption and/or for manufacturing man-made products. These natural resources include land, water, air, plants, animals, coal, minerals, natural gas, oil, and sunlight. These resources are provided by nature, we cannot produce them. However, we can use and modify them for our benefit. For example: The land is used for living, agriculture, and recreation. Water is used for drinking and eating cleaning, agriculture, recreation, and electricity generation. Air is used for producing wind energy and for manufacturing tires. Plants are used for producing timber, paper, cotton clothes, fruits, and vegetables. Animals are used for producing a variety of foods, such as milk, cheese, chicken, and for clothes like woolen sweaters, silk shirts, and leather shoes. Coal is used for electricity generation. Minerals are used for minting coins and manufacturing wire, steel, aluminum cans, and jewelry. Natural gas is used for producing electricity and heating. Oil is used for electricity generation and as a fuel for automobiles. Sunlight is used for photosynthesis in plants and for generating solar energy. Let us discuss some common natural resources in the following subsections. 1.1.1 LAND Land is one of the most important natural resources available to us. However, it is a finite resource, which is constantly shrinking due to the pressure from a growing population. Every year almost a thousand square kilometers of land disappear around the world due to urbanization, infrastructure development, increased needs for food, fiber and fuel production, and production of biomass. Land and its resources refer to the terrestrial area of the Earth, including all elements of the biosphere immediately above or below it. This includes the following: Near-surface climate Soil and terrain forms Surface hydrology (such as shallow lakes, rivers, marshes, and swamps) Sedimentary layers near the surface and associated groundwater and geohydrological reserves Plant and animal populations Human settlement patterns Physical repercussions of human activity (such as terracing, water storage, drainage structures, roads, and buildings) The following table shows the distribution of land by regions: Grassland Sparsely Cultivated Settlement and Inland water Country category Forest land and woodland vegetated and land ecosystems barren land infrastructure bodies Global Share of share of global MHA % MH % MHA % MH % MH % MH % land % population % A A A A Low- 22 38 441 15 564 20 1020 36 744 26 52 1.8 41 1.4 income Middle- 53 47 735 11 2285 33 2266 33 1422 21 69 1 79 1 income High- 25 15 380 12 880 27 1299 39 592 18 31 1 123 4 income Source: adapted from Fischer et al. (2010) Note: The extents of land cover classes were extracted from a dataset used for global agro-ecological modeling. Owing to different dates of data acquisitions, spatial resolutions, definitions, and processing techniques, the estimates in this tale may differ somewhat from those of other more recent sources. For example, the global extent of forest land is reported in FAD (2010d) as 4 billion ha versus approximately 3.7 billion ha reported here. See Annex A1 for the definition of regional and subregional country groupings. Source: http://www.fao.org/3/i1688e/i1688e03.pdf The land is used for various uses, such as for agriculture, building houses, setting up industries, mining, forestry, infrastructure development, and recreational activities. The use of land depends on the following two factors: Physical factors: Climate (temperature, rainfall, pressure, and humidity), soil types, terrain (mountains, plateaus, and plains), minerals, and forests. Human factors: Population density, technological ability, economic status, cultural values, and personal needs. The two most critical issues related to the land resource are: The decline in land quality: Due to increasing pressure on more production of crops, the quality of the cultivated land is declining more in poor countries. Each year about 5 million – 7 million hectares of land are added to the degraded cultivated land. The intense overuse of soil for farming and crop production results in its rapid erosion through wind and rain. Too much irrigation of cultivated land leads to salivation because evaporation of water brings the natural salts to the surface of the soil. The crops are unable to grow on this soil. Over-irrigation also results in problems like waterlogging which damages the roots of crops. With the growing use of chemical fertilizers, the soil is poisoned and finally, the land becomes barren. Soil erosion: The features of terrestrial ecosystems like forests and grasslands depend on the type of soil. There are different types of soil, i.e., some of them highly fertile while others not so. However, the misuse of an ecosystem will erode the precious topsoil from the land through rains and winds. Consequently, the roots of plants are not able to gain a good foothold, leading to deforestation. The process is vicious, as deforestation leads to further soil erosion. 1.1.2 WATER Water is a precious resource that is required for the existence of any life on a planet. Water exists in the form of oceans, rivers lakes, groundwater, deep subsurface water, glaciers, and icecaps. Water is a renewable resource. Its availability depends on the climate, geographical and physical conditions, and the conservation of water. The following figure illustrates the distribution of freshwater resource on the planet: Distribution of Freshwater Surface water 0.27% Groundwater 30% Glaciers and ice caps 70% Distribution of Freshwater on Earth There are three main categories of water resources, which are discussed as follows: Saltwater resources: Although 97.5% of the Earth’s water resources are oceans (saltwater), this water is not fit for drinking. The process of desalination of saltwater is very expensive. However, there are certain uses of saltwater, such as: 1. Tourism (ocean views) 2. Fishing (saltwater fish are a staple diet globally, although overfishing has started to threaten the population of marine life) 3. Generation of hydroelectric energy through tidal waters Groundwater resources: This constitutes 30% of freshwater reserves on the planet. Freshwater is formed through the water cycle. As the water reaches the ground due to rain or other precipitation, some water sticks to the topmost surface layer. This zone of the topmost layer is called the unsaturated (vadose) zone where most pores are filled with air rather than water. Water in this zone is used by plants for photosynthesis. The rest of the water seeps to the ground through the layers of soil, clay, and rock. Finally, it reaches a saturated zone where all the pores are filled with water. The following figure shows the origination of groundwater: Origin of Groundwater Source: https://www.dec.ny.gov/lands/36064.html The groundwater that seeps through layers of soil and rock is held in permeable rocks called aquifers, which have many fractures and connected pores. Limestone, sandstone, and gravel are examples of good aquifers. Shale and clay layers are poor aquifers, as they are impermeable. This groundwater erupts on the surface through springs and wells. A well is built by drilling into the ground past the water table. As water is pumped from the ground, a cone of depression is created around the well, as shown in the following Figure - Water-Table Drawdown and Recovery After Pumping >5 4 months 3 months 2 months Static water level 1 month Cone of Depression Steady-state drawdown Unconfined aquifer Zome of influence Bedrock Well Pumping Source: http://www.kgs.ku.edu/HighPlains/atlas/apdrdwn.htm The groundwater from the surrounding area fills the cone of depression. Too much pumping, however, can enlarge the cone of depressions, causing the well to run dry during scanty rainfall. The water from the well is clean and pure, as it is filtered naturally through layers of soil, clay, and rock. However, if the soil around a well is contaminated through septic tanks, the well water becomes poisonous. If the well is a near seashore, then the saltwater can be pulled into the cone of depression, making the groundwater salty. Surface water resources: The water in the streams and lakes is called surface water. This water is mostly used for drinking, irrigation, livestock, industrial use, transportation, recreation, and the generation of hydroelectric energy. Therefore, it is extremely important to maintain the quality of surface water. The quality of water can deteriorate from natural and human causes, such as dumping of oil, solvents, pesticides, and nitrogen in water making it unfit for use. The water quality is assessed by measuring its conductivity, pH, temperature, phosphorus levels, dissolved oxygen and nitrogen levels, and bacteria. Another measure of water quality is turbidity. The more turbid the water, the lower its quality is. Table - Lists some causes for the depletion of water resources and some ways to manage it: Causes Management of Water Resources High demand for water due to Treatment and recycling of effluents in urbanization and industrialization water Poor storage of water due to carelessness Rainwater harvesting Poor groundwater resources due to Non-disturbing the natural river systems overgrazing and deforestation Constructing small reservoirs instead of Bad water management big dams Loss of water in reservoirs due to Protection of wetlands evaporation Loss of water in long canals due to seepage Dumping of pollutants in water bodies Checking of overgrazing and deforestation Siltation of water bodies due to deforestation and loss of natural vegetation cover Table: Causes of Water Depletion and Measures to Prevent it 1.1.3 FOOD Food is essential for human survival, but the growing population has started to put pressure on our natural food resources. There are three main sources of food for humans: Croplands (agriculture): Although there are thousands of edible plants on the Earth, we consume only four essential crops: 1. Wheat 2. Rice 3. Corn 4. Potatoes Similarly, only a few animals are bred in livestock (chicken, pigs, goats, and cattle) for our consumption of milk, meat, and eggs. Rangelands: The rangelands are the grazing areas of animals, such as goats, cattle, and sheep. These animals are raised for milk and meat. Fisheries: Fisheries are used as a major source of protein, particularly in coastal areas. Of the above sources, most of the food from the human population is derived from croplands. There are two kinds of croplands: Industrialized croplands: These croplands consume a large number of commercial fertilizers, pesticides, fossil fuels, and water. Thus, they are called high input agricultural croplands. Mostly, a single crop is planted in a large field. Plants are selectively chosen to produce a large yield of crops. The harvested crop is sold at a huge profit. It is an expensive and technology-intensive agricultural process common in industrialized countries. Some developing countries also use this type of industrialized plantation for a single cash pasture for profit such as coffee, cocoa, or bananas. Traditional croplands: These croplands are used for traditional agricultural activities. They are mostly followed in developing countries. They can be further divided into two groups: 1. Traditional intensive agriculture: This type of agriculture uses more labor, irrigated water, and fertilizers to produce food for the farmer’s family as well as for selling in the market. Here, intercropping can be used to maintain the fertility of the soil. In this practice, two crops are planted simultaneously 2. Traditional subsistence: This agriculture produces only that amount of food that is sufficient to feed the family of the farmer. Although agriculture has provided mankind with food for centuries, it has also significantly affected the environment as follows: Deforestation: As the recent episode of Amazon fires has demonstrated, the forest area is being cut all over the world to make way for agricultural land. This has severely depleted the forest cover, which is a major source of controlling climate change. It has also imbalanced the natural ecosystems of the world and destroyed a large population of plants and animal species in those ecosystems. Soil erosion: Due to reduced vegetation cover and cattle tramping, the topsoil is eroded. The soil erosion eventually makes the land barren and causes silting of land. Irrigation: Enough rainfall is not guaranteed in drylands in arid and semi-arid regions. Therefore, irrigation is required to expand the acreage of suitable cropland. About one-third of the world’s harvest is derived from irrigated cropland. However, modern irrigation practices such as over-pumping of wells have severely degraded the croplands and aquatic systems from where the water for irrigation is drawn. Loss of genetic diversity: Deforestation of land and agriculture of the same crop (monoculture) has damaged the genetic and ecological diversity. Pollution due to fertilizers and pesticides: Crops need micronutrients and macronutrients for growth, which are supplied through fertilizers. Chemical fertilizers have been increasingly used to increase crop yield. However, they have created several problems, which are as follows: 1. Excessive level of nitrates in groundwater 2. Excessive phosphorus in water levels due to use of phosphoric fertilizers resulting in eutrophication 3. Net loss of organic matter in soils Therefore, organic fertilizers should be preferred over chemical fertilizers. Another problem is caused by the overuse of pesticides to control pests. Pesticides are also chemicals that can cause problems such as: 1. Poisoning and illness if used in high doses 2. Diseases such as cancer, birth defects, Parkinson’s disease (long-term use) 3. The decline of soil fertility 4. The killing of beneficial predators 5. Resistance among pests against pesticides and their consequent resurgence Waterlogging: Irrigated croplands result in bringing the water table near to the surface, which can cause waterlogging problems. This will decline crop productivity due to anaerobic conditions in the soils. Salinity: Salinity is caused due to intensive agricultural practices and a high concentration of soluble salts. Poor drainage causes salts to accumulate on the surface of the soil and reduce its fertility. If soils are highly concentrated in the soil, then they may form a crust on the surface, which may damage the plants. 1.1.4 FORESTS Forests are the main terrestrial ecosystem on the Earth. These are one of the most diverse and widespread ecosystems on our planet. They can be broadly categorized into biotic and abiotic components. The forest ecosystems can also be classified as follows: Tropical forests: These are mostly rain forests found in equatorial regions of South and Central America, sub-Saharan Africa, Southeast Asia, and some islands in the Caribbean Sea and South Pacific Ocean. Trees in the forest grow dense and tall due to abundant precipitation, year-round warmth, and competition for sunshine. These trees are high in biomass. They are natural habits for a diverse range of animals and birds. Decomposition occurs frequently in rainforests. In addition to rainforests, there are other tropical forests, such as cloud forests, mangroves, and deciduous forests (monsoon trees). Some tropical forest ecosystems may also have a combination of different types of forests (such as deciduous and evergreen trees). This may be due to seasonal patterns, such as the onset of monsoons after a severely hot and dry climate. Temperate forests: These forests are found in northeast Asia, eastern North America, and western and central Europe. Most trees are either deciduous or evergreen or their combination. There are defined seasons due to which temperatures fluctuate widely in these forests. These forests have exceptionally high levels of precipitation in the form of rain or snow (at higher altitudes). Due to this abundant moisture, the forest floor and tree trunks are covered with lush greenery in the form of ferns, mosses, and lichens. These trees are also high in biomass, but they have a lower diversity of species than tropical forests. Boreal forests: These forests are found between temperate forest ecosystems and the tundra in the Arctic. They are also known as taiga. They are found in Siberia, Scandinavia, Canada, and Alaska. Most of the trees are coniferous or evergreen trees. They have a large diversity of insects and migratory birds. Forests are critical for maintaining ecological balance. They play a crucial role in controlling temperature. They are a natural and huge reservoir of food and shelter for plants and animals. They provide timber, bamboo, grasses, oil, resins, gums, tanning materials, hides, dyes, fruits, nuts, roots, tubers, and other useful things for our consumption. They are also natural sources of medicinal herbs and plants. Finally, our efforts of preventing climate change depend on the conservation of forests. They are a major source of precipitation and the maintenance of water cycles. They prevent soil erosion and floods, improve the quality of land, water, and air. They are natural purifiers of water and air. 1.1.5 MINERAL AND ENERGY The Earth is endowed with naturally occurring materials called minerals. These are the homogeneous substance of organic or inorganic origin and have specific physical and chemical properties. Based on their properties, minerals can be divided into two groups, as shown in Figure: Minerals Non-metallic Metallic minerals minerals Ferrous Non-ferrous Fuels (Coal, Other non-metallics metals (Iron, metals (Copper, Petroleum, (Mica, Limestone, Manganese) Bauxite) Natural gas) Graphite) Classification of Minerals Metallic minerals: These are the sources of metals such as iron ore, copper, and gold. They are divided into two groups: 1. Ferrous metals: These metals have an iron (ferrous Fe) content. 2. Non-ferrous metals: These do not have iron content. Non-metallic minerals: These minerals are non-metals. These are divided into the following: 1. Fuels: These minerals have an organic origin. They are derived from the buried animal and plants that have become fossils over centuries. Thus, these minerals are also called fossil fuels. 2. Other non-metallic’s: These have an inorganic origin. Minerals are unevenly distributed across the globe. However, there is an exhaustible supply of minerals on the Earth. Since they are developed geologically over a long period, their rate of replenishment will take centuries. Therefore, it is critical to properly conserve them and ensure that they are not misused. Mineral fuels including coal, petroleum, and natural gas are critical for the generation of electricity, agricultural purposes, industries, and transportation. However, these are exhaustible resources. Their emission is also causing the greenhouse effect. Therefore, there has been an increased focus to gradually reduce their usage and switch over to non- conventional resources for energy. These non-conventional fuel resources will provide more sustained, cost-effective, and eco-friendly energy. These non-conventional sources of energy include the following: Nuclear energy resources: These are feasible sources of energy that require radioactive uranium and thorium as inputs. The concentrated fuel rods of radioactive uranium is used to trigger a nuclear fission reaction, which produces a large amount of heat. This heat is used to convert water into steam which, in turn, is used to drive a turbine and generate electricity. Although nuclear energy is a clean and safe method, there is a problem with disposing of radioactive wastes. Moreover, there is pressure to find sites for nuclear plants that are not vulnerable to accidents caused by earthquakes, landslides, floods, or volcanic eruptions. The twin memories of the Chernobyl nuclear accident in Ukraine and the Fukushima nuclear disaster in the aftermath of the 2011 earthquake and tsunami in Japan are still fresh in our minds Solar energy: In the areas that receive abundant sunlight, direct rays from the sun can be trapped into photo-voltaic cells and converted into solar energy. This conversion process uses photovoltaic and solar-thermal technology. Solar energy is a cost-effective, eco-friendly, and easy-to-build method of energy generation. It is 7% more effective than coal or oil-based energy generation plants. It is 10% more effective than nuclear plants. Today, solar energy is used in heaters, cookers, and crop drying activities. Wind energy: Wind energy is generated from the kinetic energy of blowing winds. In this process, permanent wind systems such as trade winds, westerlies, and seasonal winds are used to produce electricity. It is a pollution-free, inexhaustible source of energy. Tidal and wave energy: Large tidal waves in the oceans can also be used to generate electricity, particularly in windy coastal areas. Geothermal energy: Geothermal energy is generated from the eruption of magma from the interiors of the Earth to the surface. The heat and hot water that is released in this process are used to generate thermal energy. Bio-energy: This energy is derived from biological products such as agricultural residues and other urban-industrial wastes. Bio-energy is mostly used for cooking purposes, but it has the potential to generate electrical energy. This will not only improve the livelihood of rural areas in developing countries but will also reduce environmental pollution. 1.2 IMPORTANCE OF NATURAL RESOURCES The real wealth of a country is attributed to its natural resources such as oil, gas, minerals, and timber. They contribute towards the fiscal revenue, income, and poverty alleviation of nations. They are job-creators and usually the only source of income for poorer communities. There are two types of natural resource capital: Renewable resource capital: This includes forests or fish populations. These resources can be indefinitely harvested into the future, provided they are managed sustainably. The revenue generated from these resources is considered as the income derived from the flows of these resources. Non-renewable resource capital: This includes oil and minerals. These resources will eventually finish as they cannot regenerate over a period that is meaningful to human life. Thus, the revenue generated from the depletion of these resources should be evaluated as a loss of capital. Natural resources are vital to the economies of countries. Everything that we consume or use today is built from a natural resource. Our food, clothes, cars, cell phones, etc., and the essential items of our lives are built with natural resources. However, with the invasion of technology and increasing urbanization, mankind’s appetite for natural resources has grown. Put simply, we are taking more from Mother Earth than she can replenish. Moreover, once we are done with our consumption, we dump the wastes on the land, oceans, and atmosphere without any regard to the environmental balance. An irony is that the richest countries of the world consume about 10 times more natural resources than the poorest nations. According to the Global Footprint Network, if every individual in the world would like a US citizen, then we would need four more planets like Earth to sustain ourselves. Therefore, each one of us must come forward to implement the right policies and practices to do our bit to conserve natural resources. 1.2.1 NATURAL RESOURCES AND OUR PLANET According to a study by Living Planet, we are using 30% more natural resources than Earth can regenerate. As a result, Earth’s forest cover is diminishing at a rapid rate, leading to soil erosion, air pollution, and water degradation. Huge populations of fish and other marine animals are being wiped out. Each year, our ecological debt is running into trillions of dollars, based on the annual value of services provided by ecosystems such as rainfall or flood protection. If the current rate of population growth and consumption keeps up, then by 2030, we will need 1.7 more planets like Earth to sustain our current standards of living and increase economic activity. This is a conservative estimate, provided there is no sudden acceleration of climate change. In the 1960s, most countries lived within their ecological resources. However, today about ¾ of the world’s population live beyond their natural resource reserve, i.e., they consume more than they can regenerate. The ecological footprint accounting measures the demand and supply of natural resources and ecological services, as follows: Ecological footprint: This represents the demand for natural resources by a population. It evaluates the ecological assets required to produce the natural resources that they demand and absorb their wastes and emissions. These ecological assets include: 1. Cropland 2. Grazing land 3. Fishing ground 4. Built-up land 5. Forest area 6. Carbon demand on land (forest areas required to absorb carbon dioxide emissions, which cannot be absorbed by the oceans) Bio capacity: This represents the supply of natural resources by a region. It evaluates the productivity of the ecological assets of the region. If these assets are not used, then they can also absorb the waste generated through carbon emissions. 1. If the Ecological footprint of a population, Bio-capacity of that region, then, that region runs an ecological deficit. In other words, the demand for the natural reserves by the population is more than what the ecosystems in the region can regenerate. To meet its demand, that region (country) does the following: 2. Import natural resources from other regions 3. Liquidate its ecological assets such as over-fishing 4. Emit carbon dioxide into the atmosphere On the other hand, if a population’s ecological footprint, Biocapacity of that region, then that region has an ecological reserve. Both ecological footprint and biocapacity are measured in global hectare (GHA) units. The following table shows the world-average ecological footprint and biocapacity: Table 3: World-Average Ecological Footprint and Biocapacity in 2016 World-average Ecological Footprint World-average Biocapacity By person 2.75 GHA 1.63 GHA Total 22.6 billion GHA 12.2 billion GHA Thus, the global ecological deficit is 2.75 – 1.63 = 1.12 GHA per person And 22.6 – 12.2 = 10.4 billion GHA in total To sustain our ecological resources, we need to have a smaller ecological footprint than the bio-capacity of the planet. If a country consumes more than 1.73 GHA per person of natural reserves, then its demand for reserves is not sustainable. The following table shows the top 10 ranked countries by ecological footprint as of 2016: Table 4: Top 10 Ranked Countries by Ecological Footprint Bio The Ecological Bio capacity Populati Total population Ran Country Footprint capacity deficit or on Biocapac when k (GHA/per (GHA/ reserve (millions ity Biocapacity son) person) (GHA/ of (gMha) equals person) Ecological people) Footprint* 1 15.82 1.68 −14. 0.52 −7.35 0.0552 Luxembourg 14 21 2 Aruba 11.88 0.57 −11. 0.1 −1.13 0.0047 31 98 3 Qatar 10.8 1.24 −9.5 2.05 −19.60 0.2353 6 7 4 9.31 16.57 7.26 23.0 167.34 41.024 Australia 5 54 5 United 8.22 3.76 −4.4 317. −1416. 145.23 States 6 5 05 11 6 Canada 8.17 16.01 7.83 34.8 272.80 68.272 4 75 7 Kuwait 8.13 0.55 −7.5 3.25 −24.64 0.2198 8 65 8 7.97 0.05 −7.9 5.3 −41.98 0.0332 Singapore 2 5 9 United 7.93 0.56 −7.3 65.6 −483.8 4.6359 Kingdom 7 48 3 24 10 Trinidad 7.92 1.56 −6.3 1.34 −8.52 0.2639 and Tobago 6 39 Source: https://en.wikipedia.org/wiki/List_of_countries_by_ecological_footprint 1.2.2 EXPLOITATION OF NATURAL RESOURCES Overpopulation, urbanization, modern technology, requirements, lifestyle changes, and the race to economic growth has put the natural resources on the planet under considerable stress. Resources like land, water, timber, paper, and minerals like gold and silver were always used. But post-industrialization, we discovered new technologies which required new resources. Oil was discovered. Coal mines emerged. We started urbanization on a large scale. Our industries dumped effluents in rivers and lakes, polluting them irrevocably. We bored deep wells into the ground to irrigate lands for our cash crops. In the process, we ran the land dry. To fuel the demand for more land for urbanization, we started cutting down forests on a large scale. We discovered new means of traveling, which required oil-guzzling vehicles like airplanes. All of these activities exploited natural resources. This exploitation began in the early 19th century when natural resources were extracted and processed for mines, steam engines, and machinery in industries. The increased consumption of energy in the 20th century speeded up the process. Today, almost 80% of our energy consumption is based on the use of fossil fuels, including oil, coal, and gas. The topmost resources that are under maximum pressure due to the current rates of consumption are: Water: Freshwater only makes up 2.5% share of the water resource available on the earth. 70% of freshwater is in the form of glaciers and icecaps. Thus, we have only 30% of the freshwater stock available to use, which is about 200,000 cubic kilometers of supply. As per the Food and Agriculture Organisation (FAO) of the UN, 1.8 billion people in the world will live with absolute water scarcity by 2025. Oil: The oil industry is spooked by the fear of exhausting the oil supplies. According to the BP Statistical Review of World Energy, at the current rate of consumption, the oil reserves will only last till the year 2056. Natural gas: At the current rate of consumption, the natural gas reserves with enough gas will last only till the year 2069. Phosphorus: It is a necessary ingredient for the growth of plants in the soil, and hence it is a key ingredient of fertilizers. Phosphorus is found only in some countries such as the US, China, and Morocco. According to the Global Phosphorus Research Initiative, the current phosphorus reserves will be exhausted by 2060 to 2100 until new reserves are found. Coal: Of all fossil fuels, coal has the largest reserves. However, with the growing consumption of coal in China and other developing countries, the coal reserves will last only for the next 178 years. Rare earth elements: Rare earth elements such as scandium (Sc) and terbium (Tb) are used for manufacturing electronic circuits in smartphones and magnets in wind turbines. 97% of these elements occur in China. Their exact reserves are not known. 1.2.3 REASONS FOR EXPLOITATION There are several reasons behind the exploitation of natural resources. Some of them are as follows: Economic growth: The 21st century will be noted in history as the century of emerging markets like China, India, Brazil, Russia, South Africa, Malaysia, and Indonesia. By 2030, it is estimated that these emerging markets will drive 66% of the global economy. However, as compared to developed countries, these countries will have a higher consumption of natural resources. In 2010, China became the largest consumer of energy in the world, overcoming the US. Despite that, the per capita consumption remains low, which means that over the coming years, the demand from China for energy will rise further. India is one of the world’s fastest-growing major emerging markets. However, it's per capita energy consumption is only 1/3rd of China’s. Thus, it is evident that as these giants will grow, their need for energy will also increase in large quantities. Overpopulation: The global population is set to reach 8.5 billion by 2030. 95% of the growth will be driven by the youth and growing populations of emerging countries. The urban population is estimated to grow at twice the rate of the global population. By 2030, there will be 4.2 billion people living in urban areas. These people will need housing, infrastructure, transport, food, energy, and other consumable products. As a result, the strain on natural resources will increase tremendously. Income gains: The emergence of the middle class globally has considerably increased consumption. According to the Euro monitor International, a leading market research organization, the number of households earning more than $10,000 increased by 27% from 2010 to 2015. If this trend continues, it is estimated that the consumption expenditure in developing countries will increase by 89% by 2030. For instance, the average disposable income of more than ¾ of Chinese households will increase to $10,000 in 2030. These households will purchase more consumer goods, putting an increasing demand for natural resources, including food, water, energy, and minerals Environmental change: Due to environmental concerns, there is a global shift in the demand for some materials relative to others. For example, the demand for natural gas and renewable energy sources is increasing, while that of coal is decreasing across the globe. Similarly, there is an increased focus to replace toxic materials such as lead in batteries with lithium. Consequently, the production of lithium has increased by 30%. Technological advancement: Advances in technology have increased the demand for specific resources. For example, the increased demand and production of Electric Vehicles (EVs) will put pressure on minerals such as lithium, graphite, and cobalt. Similarly, the increased penetration of mobile phones globally has fuelled the requirement for rare earth elements. The push towards the use of solar cells has increased the demand for silicon, which is used in photovoltaic cells. Pressure on price: The demand for natural resources is impacted by their price fluctuations. For example, the demand for solar and wind energy increased when their costs declined due to the availability of new technology or governments’ subsidies. 1.2.4 BURDEN OF OVERPOPULATION ON NATURAL RESOURCES Today, we are 7.2 billion and growing by 74 million people every year. The world population will be 9.6 billion by 2050 (UN estimate). This explosion of the population is fairly recent. Till 1804, the human population was less than 1 billion, but the industrial revolution and improvements in nutrition, medicine, and technology changed the equation forever. The increasing lifespan of people due to modern medicine has put much pressure on natural reserves. Naturally, the growing population will need food, clothes, education, income, gadgets, recreation, etc. Since the last century, humans have consumed more resources than ever before. After evaluating the devastating impacts of the huge population on the earth’s natural resources and environment, scientists have proposed our period to be called the Holocene or Anthropocene epoch. In other words, unlike previous geological epochs when climate and geological processes defined the periods, humans have emerged as a new global geophysical force that has and continued to shape our period. Let us none explore some factors to further understand the burden of population on natural resources: Population size: We have only one planet with a finite number of resources to sustain life. The consumption of resources is unevenly distributed around the world. For example, an average American eats 3.3 times more food and consumes 250 times more water than the subsistence level. Hence, if all the people in the world start living like Americans, then Earth will only be able to sustain 2 billion people, rather than the current 7.2 billion. Overpopulation will not only exhaust our natural resources supply but will also lower the standard of life and create huge income inequalities. Population distribution: Developing countries have a higher rate of birth than developed countries due to poverty, lack of family planning, and education. 80% of the current population is living in developing countries. Their growing numbers are putting additional pressure on local environments. Half of that population is moving to urban areas in search of better employment opportunities. However, the rate of population migration is much higher than the rate of infrastructure development. Most of these people live in refugee camps or slums, which have put even further pressure on water supplies, have caused land damage (such as cutting down of trees for fuel), and polluted environments (due to lack of sewage systems). Population composition: The largest shares in the current population are of: 1. Young people (under 24 years): These people are more likely to migrate to urban areas, resulting in environmental concerns. 2. Elderly people (over 60 years): Since 1960, the average life expectancy has increased by about 20 years due to better nutrition and medical science. Although it is a major achievement for the advancement of humanity, it is bad news for the earth’s resources. This is because an elderly person living 40% longer than in the past is just another body consuming resources and generating waste. With the growing number of people getting old, there will be increased requirements of government spending on pensions and healthcare. Population income: The rising inequality among populations is also putting pressure on natural resources. The need for survival induces poor people to consume natural resources in an unsustainable manner, which are as follows: 1. Burning of waste, tires, or plastics for fuel 2. Cutting down of trees to get wood 3. The killing of protected animals to feed their families 4. Burning down of forests to expand the farm area 5. Allowing their cattle to graze from the forests 6. Expanding villages to the protected forest reserves 7. Lynching wild animals that venture into human settlements due to cutting down of their natural wild habitats 8. Overfishing of aquatic bodies 9. Use of agrochemical and harmful pesticides to produce crops On the other hand, the affluent lifestyle of rich people is also draining natural resources. They purchase, consume and use disproportionately a large number of levels of houses, cars, food, gadgets, clothes, and other products. From the country-level perspective, the resource consumption pattern is as follows: Rich (most developed) countries: These countries have historically consumed unduly high levels of resources in the last 70 – 100 years as they were growing economically. However, now they have taken effective steps to curtail their resource consumption while maintaining high levels of production. To reduce their ecological footprint, they are implementing innovative ways of improving technology and energy efficiency and are strictly enforcing environmental protection policies among their populations at large. Poor (least developed) countries: Since these countries have lower levels of industrial activity, they put the least pressure on environmental resources. However, the lack of education among the population regarding population growth and sustainable use of resources are matters of concern. Middle income (developing) countries: The overpopulation, requirements of urbanization and infrastructure development of the growing population, and the intense resource consumption among the population are serious concerns in these countries. When economic development was taking place in the US the world had more natural resources than reserves we have now. The large population countries like China and India consume more resources as a result. The stocks of natural reserves are simply not sufficient for the population’s demand. Population consumption: The unsustainable patterns of production and consumption in developed countries are putting a severe strain on natural resources. Unfortunately, the overconsumption of goods and resources is a part of their life and culture. For example, for some rich and privileged people in the US, hunting animals is a way of life. For an average person in the US or Europe, purchasing the latest model of a car, moving to a bigger house, and striving for a jet-setting life are signs of personal success. However, such a lifestyle fed by unstoppable consumption is neither healthy for the earth or the individual’s emotional health. Companies produce goods in large quantities for-profit and spend billions of dollars on advertisement and promotion to fuel their demand. All these goods, which are not required for a comfortable life, are depleting large reservoirs of energy, minerals, water, land, and other resources for production. They are creating pollution during production through effluents and their wastes are getting harder to dispose of. According to the Global Footprint Network, today, humanity uses the equivalent of 1.5 planets to provide the resources we use and absorb our waste. This means it now takes the Earth one year and six months to regenerate what we use in a year. 1.2.5 BURDEN OF INDUSTRIALISATION ON NATURAL RESOURCES Ever since the industrial revolution in the 18th century, the demand for natural reserves has exponentially increased. Today, we are moving towards the fourth industrial revolution. Before we learn about it and understand its implications on the natural reserves, let us revise the key points about the first three industrial revolutions, which are discussed as follows: First industrial revolution: This period is known as the age of mechanical production. It began around 1760 in Great Britain and from there it spread to the rest of Europe and then to America. Before this period, human society was mostly agrarian. With the invention of the steam engine, factories powered by steam engines emerged. However, life in factories was tough. There was a surplus of cheap and unskilled laborers, who were forced to work long hours in unsafe conditions. Even children used to work 14-hour shifts in factories. These conditions prevailed till the beginning of the 20th century. This period also created a new social class in society called the middle class of skilled workers. As factories grew, people migrated to work in them. Cities started to grow rapidly. These growing factories and cities required large supplies of coal, iron, wood, and cash crops. Consequently, the world was divided into two zones: 1. Industrialized countries: These countries manufacture products for other countries as they have more industries e.g., England. 2. Less industrialized countries: These countries provide the raw materials (from their natural reserves) to other countries for the production of goods e.g., India. Due to this division of labor, industrialized countries started colonizing other countries to gain control over their natural reserves to meet the increasing demand for coal, iron, and textiles. Several colonized countries became highly dependent on cash crops such as sugar, cotton, and rubber, which made their fertile fields barren. Due to colonization, migration of people started. The factory owners traveled to their colonies, while large numbers of workers were brought as indentured slaves to work in factories. Consequently, sea travel became more efficient. New canals were opened to reduce travel time. Second industrial revolution: This was the period of critical scientific inventions such as gasoline engines, airplanes, and chemical fertilizers. The scientific principles were also applied to the factories. People migrated in large numbers to urban areas to work in these mass-production factories. An increase in urbanization brought inventions such as electric lighting, the radio, and telephones. Forests were cut down to build cities to accommodate the urban population. To feed the growing population, intensive agricultural methods were adopted where chemical fertilizers were used liberally to increase the crop yield. The discovery of oil in the Middle East changed the word equation, and oil-producing countries controlled the price of oil. Innovative and useful products were made from fossil fuels. The mass consumption of these products increased the amount of greenhouse gas emissions such as carbon dioxide. The increased levels of greenhouse gases depleted the Ozone layer in the atmosphere and introduced the threat of climate change. Third industrial revolution: This is called the period of the digital revolution. It started in the 1950s when semiconductors, mainframe computing, personal computing, and the Internet were invented. From analog electrical and mechanical devices, factories started producing digital devices. Digital technology has proved to be a disruptive force for the old way of industrialization. It has revolutionized the way the world communicates and uses its energy. Automation was introduced in factories and supply chains became global. Fourth industrial revolution: The fourth industrial revolution, also called the 4IR or Industry 4.0, is driven by innovation. It is a fusion of the physical, biological, and digital technologies that will not only transform how humanity will produce and consume resources. Sustainability development is the goal of the fourth industrial revolution. It will bring new technologies such as Artificial Intelligence (AI), robotics, the Internet of Things, 3D printing, genetic engineering, etc. In 2015, all the UN member states adopted 17 Sustainable Development Goals (SDG) to eliminate poverty, ensure peace and prosperity of all people, protect natural reserves and save the planet by 2030. 4IR is based on these SDG goals, which will be discussed in the next section. 1.2.6 CONSERVATION OF NATURAL RESOURCES Conservation of natural resources in the preservation of resources so that all the natural resources are utilized efficiently. Conservation of natural resources is essential to protect and care for the resources so that they can be perpetually kept for future generations. Conservation of natural resources in promoting and protecting the natural resources for the future generation. Although both aim to protect natural resources, their modus operandi is different. Some of these are discussed as follows: Conservation of natural resources: This means sustainable use of natural resources during human activities. For example, National Forests in the US are open for human activities such as logging, cattle grazing, hunting, and recreational activities, provided these activities are done sustainably. Preservation of natural resources: This means the protection of resources by emphasizing minimal change to the landscape and environment. For example, National Parks in the US are preserved. Absolute conservation: This approach of Conservation Focus is on the sustainable use of natural resources so that they are preserved in the same condition as they currently exist in nature. The objectives of absolute conservation are to: 1. Work with nature and stop working against it 2. Interfere with other species only for basic requirements 3. Stop wastage of resources 4. Protect environmental damage Relative conservation: This approach focuses on the integration of conservation programs when using natural resources. Examples are as follows: 1. Reuse and recycle resources 2. Minimum use of non-renewable resources such as fossil fuels 3. Use plant resources in limited quantity 1.2.7 NEED FOR CONSERVING NATURAL RESOURCES Conservation of natural resources is essential, as their overconsumption, careless use, and exploitation have caused the following problems: Deforestation: This is the act of cutting down forests for non-forest uses such as agriculture or urban development. Without sufficient reforestation programs, removal of trees can cause loss of biodiversity, decline, and extinction of species due to the loss of their natural habitats, soil erosion, conversion of fertile land into a wasteland, climate change, increase in greenhouse gases leading to global warming, change in weather conditions due to damaged hydrological cycles, and loss of long-term income and biological productivity. Desertification: This is a type of land deterioration where a once fertile land starts losing its water bodies, vegetation, and wildlife, eventually becoming a desert. The main cause of desertification is overexploitation of soil due to human activities such as deforestation and overgrazing. The process is speeded up by climate and weather change. Figure 1 shows the vulnerable areas of desertification in the world: Figure1: Global Desertification Vulnerability Map Source: https://en.wikipedia.org/wiki/Desertification At least 90% of the highly vulnerable dry areas are based in developing countries. Overpopulation and economic pressures in these regions cause poor people to overexploit lands in the forms of overgrazing, deforestation, and tillage for agriculture. A theory suggests that the Sahara desert was once a savanna but due to climate change and overgrazing by cattle, it became a desert. Extinction of species: Earth is going through the sixth mass extinction of species known as the Holocene extinction. This mass extinction is mainly due to human activities related to the over-exploitation of natural resources. With the extensive deterioration of ecosystems and biodiversity, several families of plants and animals have become extinct. Many of these species were not even discovered and studied. The Holocene extinction will continue into the next century due to our overpopulation and overconsumption of resources as well as environmental pollution. Forced migration: This is the forced movement of a person (people) from their homes due to living hardships such as war or drought. Consider the dark areas in Figure 1. These areas in Africa and Asia are those areas from where refugees are fleeing in large numbers and seeking shelter in Europe and elsewhere. Apart from the ongoing war in these regions, a major cause of this displacement is also because it has become hard to earn a sufficient livelihood there. Most of these areas have become dry and the land is simply not sufficient enough to feed the large populations there. Oil depletion: This is the lowering of oil production in an oil well, field, or area. The supply of natural oil is limited because the natural formation of oil takes millions of years. At the current rate of consumption, the oil reserves are likely to be exhausted by 2056. This will have critical repercussions on the world economy. Despite the progress made on renewable sources of energy, our industrial economy still relies heavily on oil as a fuel and chemical input. A key product of oil refining is a pesticide. Since the invention of pesticides, food production has risen dramatically. Shortage of oil may force people to switch over to organic agriculture methods. Since organic farming is more labor-intensive, large populations may need to shift from urban to rural areas. The shortage of oil will also have a more visible effect on our transportation methods. Soil erosion: Soil erosion is a natural process caused by geological factors such as water flow and wind movement. However, human activities have unnaturally increased this activity by 10-40 times, causing severe loss of nutrients in the soil. The harmful activities causing soil erosion include deforestation, road development, and urbanization. When the nutrient-rich upper soil layers are removed from the land, the quality of the land deteriorates and it becomes barren. Increase in greenhouse gases: The earth’s atmosphere contains greenhouse gases such as water vapor, carbon dioxide, methane, nitrous oxide, and ozone. These gases (GHG) trap the heat of the Sun, which makes the earth’s atmosphere liveable. However, since the industrial revolution, human activities have increased the concentration of carbon dioxide in the atmosphere by about 45%. These activities include the burning of fossil fuels, deforestation, agricultural use, and soil erosion. Environmental pollution: To encourage overconsumption, industries are polluting natural resources blatantly. Record numbers of wastes are being generated. Natural land areas and oceans are being dumped with rubbish. Waste disposal has now become a matter of conflict among countries. For instance, recently a court in the Philippines ruled to return the ships containing wastes to Canada. Natural disasters such as floods and landslides: Flooding, hurricanes, and landslides have become common news across countries. Their destruction to life and property has become more widespread, regular, and expensive. A major reason for their frequent occurrence is the loss of natural barriers such as forests and vegetation, which are used to regulate the flow of water and maintain the balance of the water cycle. Water scarcity: If floods and landslides are causing devastation in one corner of the world, then more than half of the world is grappling with severe water scarcity. Although water is a renewable natural resource, its wastage and pollution are fast depleting the freshwater reserves. Minerals depletion: The desire to purchase the latest mobile gadgets and other products are resulting in the over-extraction of minerals. Minerals have limited stocks in the world and a very slow regeneration process 1.2.8 METHODS OF CONSERVING NATURAL RESOURCES Conservation of natural resources is an integrated effort by the governments, industries, and local populations. Some popular methods of conserving natural resources are: Conservation of freshwater: This can be done by adopting methods such as rainwater harvesting, preventing water pollution, and reforestation. People should be educated to use water judiciously for their daily activities such as drinking, bathing, washing, cooking, etc. They must ensure that taps are closed when they are not being used and take less time in the shower. Some of the water can be reused for watering gardens and washing. Excessive use of water for agriculture should be discouraged by using drip and other water delivery systems. The use of chemicals for washing floors and farming purposes should be discouraged, as these chemicals pollute the water and make it non-renewable. The sewage of industrial wastes into surface water bodies like rivers and lakes must be stopped immediately. Waste treatment plants should be set up to prevent thermal and chemical pollution of water bodies. The use of plastics and other harmful products must be banned so that water reservoirs are not clogged. Rainwater harvesting must be taken up by individuals and institutions on a large scale. In this method, rainwater is collected, stored, and used in different ways for recharging water bodies. Small water reservoirs should be constructed to store water. Conservation of air: The quality of air in urban cities in developing countries is a critical concern. Every year health warnings are generated in cities like New Delhi and Beijing on account of air pollution and the heavy concentration of particulate matter in the air. Businesses attempt to profit from this man-made pollution by selling products such as air purifiers and masks. However, the need of the hour is to reduce air pollution. This can be done by encouraging the use of electric vehicles instead of vehicles run by fossil fuels, incentivizing farmers not to burn their crop wastes, regulating the construction activities so that less dust is accumulated in the air, treating industrial effluents before they are released into the atmosphere, encouraging the use of biofuels instead of fossil fuels for domestic purposes and planting trees in home compounds (natural air conditioners). Conservation of soil: Although soil is a renewable resource, it replenishes very slowly. Soil erosion is a natural process where the topsoil is washed away naturally by winds and rainwater. This layer of soil is the most fertile for the growth of plants and crops. It binds the roots of plants to the ground. When the topsoil is eroded, then the bottom rock gradually becomes the topsoil. However, overgrazing and deforestation have drastically eroded the topsoil. Soil can be conserved by reforestation as trees can slow down the natural erosion of the soil. Trees are also natural habitats for most plants, birds, insects, and animals. Therefore, reforestation is an effective method of conserving wildlife also. Wastes such as plastics and paper bags should be recycled to avoid pollution. Planting the same crop for a long period may deplete its nutrients level. Therefore, crop rotation should be adopted to restore and maintain soil fertility. The number of cattle per household must be regulated to control overgrazing. Finally, the construction of terraces and gabions in sloping land will prevent soil erosion. Conservation of forests: There must be strict implementation of laws against cutting down trees in the forests. Forest officers must remain vigilant against forest fires and other hazards. The following methods can help to save trees: 1. Planting of more trees to reduce the natural reduction in tree population due to old age, heavy winds, or rains 2. Using tree guards to protect the small trunks of newly planted trees or saplings from cattle grazing 3. Using organic fertilizers to increase the lifespan of plants and protect them from diseases and pests 4. Growing more fruit-bearing trees instead of just ornamental trees so that people have less desire to cut them down if they find them intrusive 5. Adopting organized methods to prevent excessive deforestation due to urbanization or clearing of land for agriculture 6. Using less paper to save trees 7. Reusing old furniture in novel ways to discourage cutting of wood 8. Minimizing the use of disposable wood material such as wooden spoons, plates, and utensils. 9. Enforcing legislation to prevent the unnecessary expansion of layouts by businesses or households 10. Making cultivation of trees mandatory in case of urban development work 11. Offering financial incentives to unemployed youth or old people to grow and preserve trees voluntarily Conservation of rivers and lakes: Encroachment of lakes, manmade changes of river routes or courses, and excessive weather conditions like drought have dried up several rivers and lakes. The large-scale pollution of water bodies also makes their water unfit for human consumption. Therefore, to conserve rivers and lakes, strict measures must be adopted to prevent land encroachment and pollution of water bodies. The sources of water for most rivers and lakes are the catchment areas. These catchment areas should be protected by growing vegetation in them so that water can percolate sufficiently into the deep soil layers. This will keep the groundwater levels adequate. The concretization of land around rivers and lakes should be discouraged so that natural vegetation allows groundwater to build up during rains. Conservation of oceans: Our oceans are at risk due to overfishing, plastic pollution, and frequent spillage of oil and other contaminants. The water from polluted rivers also merges into the oceans making the situation worse. The changes in the water pH are killing natural ecosystems like the Great Barrier Reef in Australia. Hence, urgent actions must be taken to check the pollution of ocean water to save marine biodiversity. To prevent oil leaks in the oceans, pipelines should be used to transport them instead of oil tankers. Conservation of fossil fuels: The depletion of oil can be slowed down by using public transport more than personal vehicles for traveling. Switching over to electric vehicles is another option. Overconsumption of coal can deplete its reserves. Hence, other renewable sources of power should be encouraged. A by-product of oil refining is Liquefied Petroleum Gas (LPG). It is the most prevalent source of fuel in households. However, its continued use may deplete oil reserves. An alternative is the use of biogas, which is produced from cattle dung. Biogas also causes less air pollution. Conservation of minerals: Minerals are a finite resource. They also do not have any alternatives. Therefore, the only way to conserve them is to use them minimally and judiciously. The old products containing minerals must be recycled to conserve them. Conservation of biodiversity: Reforestation and preventing hunting of animals for sport or food can help to prevent loss of biodiversity. Unfortunately, despite laws, poachers continue to kill many animals to sell their teeth, horns, and skin on the black market. They have become the biggest threat to biodiversity. To resolve this issue the forest officers must be extra vigilant to catch them. The government of the world should also act collectively against the black markets for wildlife products. 1.3 SUMMARY Natural resources on the Earth include land, water, air, plants, animals, coal, minerals, natural gas, oil, and sunlight. We have built our life around these natural resources. Natural resources are the real capital of a country, which contribute to its fiscal revenue, income, and poverty alleviation. They are job-creators and usually the only source of income for poor communities. To sustain our ecological resources, we need to have a smaller ecological footprint than the biocapacity of the planet. Humans are the biggest consumers that have an inexhaustible demand for natural resources. The IPAT formula states that the environmental impact is the product of population, average consumption rate, and available technology. Water, oil, natural gas, phosphorus, and fossil fuels are the topmost resources that are threatened by overconsumption. The reasons for the exploitation of natural resources include economic growth, overpopulation, income gains leading to overconsumption, environmental change, technological advancement, and price pressure. Conservation of natural resources is essential to prevent socio-economic and political problems caused due to deforestation, desertification and mass extinction of species, soil depletion, soil erosion, greenhouse gas emission, pollution, natural disasters, water scarcity, and minerals depletion. Some popular methods of conservation of natural resources include reforestation, preventing pollution, rainwater harvesting, recycling and reusing products, lowering consumption, and managing waste production. Some initiatives taken to conserve natural resources include UN SDGs, OECD guidelines, ICC Business/Sustainable Development Declaration, ISO 14001 series, GRI, FSC, MSC, etc. 1.4 KEYWORDS Precipitation: A weather condition when rain, snow, or hail fall from the sky. Herbivorous: The animal whose main diet is the plant material and, thus, it has mouth-parts adapted to grinding. Carnivorous: The animal that kills and eats other animals. Omnivorous: The animal that eats other plants and animals. Food chain: A system where different animals are interlinked with their feeding habits, for example, a plant is the food of an animal, that animal is the food of another animal, which is again the food of a larger animal. Crustaceans: The invertebrate animals that serve as a principal food for a variety of marine animals. They include crabs, lobster, and shrimps. Diurnal variation: Variation that occurs during each day. UNIT – 2: Pollution Control Objectives After going through this unit, you will be able to: Explain the meaning ofpollution Elucidate airpollution Discuss waterpollution Explain soilpollution Describe nuclearpollution Discuss the major hazards ofpollution Outline the causes of pollution and the harmful effects ofpollution Describe the methods to controlpollution Explain nuclear hazards and meaning and reasons for nuclearhazards Structure 2.1 Meaning Of Pollution 2.2 Types Of Pollution 2.2.1 Air Pollution 2.2.2 Water Pollution 2.2.3 Soil Pollution 2.2.4 Noise Pollution 2.2.5 Thermal Pollution 2.2.6 Marine Pollution 2.2.7 Nuclear Pollution 2.3 Major Hazards of Pollution 2.3.1 Causes of Pollution 2.3.2 Harmful Effects of Pollution 2.3.3 Overpopulation and Pollution 2.3.4 Rapid Industrialisation and Pollution 2.4 Control of Pollution 2.4.1 Methods to Control Pollution 2.4.2 Steps Were Taken by The Government to Control Pollution 2.4.3 Role Played by Various Organisations to Control Pollution 2.5 Nuclear Hazards 2.5.1 Meaning and Reasons for Nuclear Hazards 2.6 Solid Waste Management 2.6.1 Meaning and Importance of Solid Waste Management 2.6.2 Methods of Solid Waste Management 2.7 Role of an Individual In Prevention of Pollution 2.8 Key Words 2.9 Summary 2.1 MEANING OF POLLUTION The word pollution originates from the Latin word, pollute-, which means soiled or contaminated. Pollution is the act of adding soiled, contaminated, or harmful materials into the environment, which makes the environment dirty, unsafe, and non-suitable for use. The soiled or contaminated materials are called pollutants. These pollutants need not always be tangible or physical. Incorporeal things such as light, sound, and temperature can also cause pollution if these are introduced to the environment artificially. Overproduction and overconsumption have resulted in a disbalance that continuously damages the environment. The extent of the damage is so high that the environment is unable to regenerate at the rate at which we are damaging it. Our dependence and high usage of vehicles are releasing millions of effluents in the form of toxic gases and particulate matter into the air. The thermal electricity plants burn thousands of tons of coal to meet our energy demand. In the process, plants release toxic chemicals into the air. Our households and industries generate sewage that is directly added to the land and water as garbage. Our crops are grown by adding toxic pesticides into the soil to kill weeds and insects. These poisonous chemicals percolate into the waterways and make our rivers toxic. Today, more than 200 million people around the world are exposed to the ill-effects of this toxic pollution. In some of the most polluted areas, children are born with congenital defects due to pollution. Cancers and other diseases have become quite common due to pollution and its side effects. Pollution is not a local problem that is limited to one country or population or species. The planet, its other species, and ecosystems are interconnected because we share the Earth’s supply of natural resources. Thus, if these resources are polluted, then all the living beings will be endangered. Besides, pollution is not limited to one area it is the challenge that every country is facing. For example, harmful chemicals and pesticides have been found even in the remote, far-off, desolate continent of Antarctica. A large deposit of minuscule plastic particles has formed a garbage patch in the middle of the Northern Pacific Ocean. Smoke emanating from factories in one country can easily travel to other countries. Accidental oil spills in an ocean or the release of radioactive materials in the air are global dangers. This is because the oil and radioactive materials can be carried by water and wind currents across the world, creating problems for everyone. History of Pollution Pollution is as old as the invention of fire in prehistoric times. When humans learned to forge metals, air pollution entered the external environment. Humans also used to take water from freshwater resources such as rivers and oceans for drinking, bathing, livestock, and agricultural purposes. Of course, the sewage from the households went into rivers and oceans. However, the natural replenishment purposes must have been adequate to renew the polluted areas. The problem started with the Industrial Revolution, when newly formed industries in London, Berlin, Paris, and Chicago dumped industrial wastage in the rivers, created landfills full of untreated waste, and released toxic effluents from their fuming mills into the air. Nowadays, developing cities such as New Delhi, Mexico City, Beijing, and others are grappling with smog caused due to the mixing of harmful particulate matter into the air particles. Breathing polluted air in these cities is equivalent to smoking hundreds of cigarettes, causing problems such as asthma and bronchitis. The topmost polluting countries are: China US Russia India Mexico Japan The major causes of pollution in these countries are emissions from fossil fuels, refineries, petrochemical plants, disposal of nuclear wastes, large livestock farms, plastics factories, etc 2.2 TYPES OF POLLUTION There are various forms of pollution. The most damaging forms of pollution are: Air pollution: It is caused due to the release of toxic chemicals and particulate matter into the air Water pollution: It is caused due to the discharge of sewage, untreated wastes, and chemicals from fertilizers and pesticides from domestic and industrial areas into rivers, lakes, and other sources of surface water Soil pollution: It is caused due to the overuse or spillage of chemicals into the soil layers Noise pollution: It is caused due to high-intensity, harmful noise levels from vehicles, aircraft, and industries Thermal pollution: It is caused due to the artificially induced change in the temperature of natural water bodies Marine pollution: It is caused due to the spillage of oil and the dumping of waste materials in oceans and seas Nuclear pollution: It is caused due to the of disposal chemicals and accidents in nuclear power reactors, where radioactive materials are released into the environment Let us discuss each form of pollution in detail. 2.2.1 AIR POLLUTION Air pollution can be termed as the pollution of air when harmful get mixed in the atmosphere quantity of gases, particles, and biological molecules. Air pollution is a combination of natural and man-made substances in the air humans inhale. A pictorial representation of air pollution is shown in Figure Air Pollution in New Delhi Source: https://www.outlookindia.com/website/story/delhi-air-pollution-no2-level-rises- in-the-national- capital-despite-fall-in-dies/306695 The polluted air is toxic to breathe. It causes allergies and even death to living organisms. It damages crops and other livinghabitats. Air pollution can happen anywhere, outdoors or indoors as discussed in the following points: Outdoorairpollution:Theairpollutionthatisoutsidetheboundaryofaninbuilt environmentorestablishmentiscalledoutdoorairpollution.Forexample,the burning of fossil fuels, such as coal and petroleum, introduces fine particles into the atmosphere causing airpollution. Indoorairpollution:Theairpollutionthathappenswithinaninbuiltenvironment is called indoor air pollution. The indoor air pollution is inside in non-ventilated houses where people spend most of their time inside. Examples of indoor air pollution include: o Gases, such as radon ooze from inside the earth in some locations and sometimes get trapped inside houses. These gases aretoxic. o In a building under construction, materials such as carpeting and plywood emit formaldehyde gas. Although banned, asbestos is still used in building materials. Its prolonged exposure can cause breathing problems, lung cancer, and a very rare form of cancer called PeritonealMesothelioma. o Whenpaintsandsolventsdry,theyemitVolatileOrganicCompounds(VOCs). If the paint has a lead component, then the lead can decompose into dust, which mixes into the air making ittoxic. o The use of air fresheners, incense, and other perfumed items also causes indoor airpollution. o Wood fires from stoves and fireplaces add a significant amount of smoke into theair. o The use of pesticides and other chemical sprays in houses without proper ventilation may befatal. o The burningofcharcoalsinaclosed,non-ventilatedspaceresultsintheaccumulation of poisonous carbonmonoxide. o Dustduetodecomposedhair,pets,bedding,carpeting,andfurnitureproduces enzymes, which emit methane (a greenhousegas) Air pollutants These are the solid, liquid, or gaseous substances that can mix with the air and contaminate it. These can be natural or manmade. These can also be classified as: Primary air pollutants: These are caused directly by natural or manmade processes. For example, ash from volcanic eruptions, carbon monoxide from automobile exhausts, and sulfur dioxide from industrial emissions are primary pollutantsofthe air.In2010,theeruptionofavolcanoinIcelandnamedEyjafjallajökull created a huge ash cloud. This ash cloud spread across Europe and suspended international air travel for 6days. Secondary air pollutants: These pollutants are created by the mixing of primary pollutants. For example, smog is created by the mixing of smoke and sulfur dioxide from coal-burning, vehicular emission, and industrialemission. The tablelists the main pollutants: Main Pollutants Main Pollutants Sources Why is it a pollutant? Carbon dioxide Respiratory systems of all aerobic It is a greenhouse gas whose organisms, the decay of organic atmospheric concentration has materials, fermentation, rapidly increased due to the burning volcanoes, hot springs, geysers, of wood and fossil fuels. Its high dissolution of carbonate rocks in concentration in the atmosphere is water, combustion of wood and causing global warming. fossil fuels Main Pollutants Sources Why is it a pollutant? Sulfur dioxide Produced in volcanic eruptions, It damages human health and industrial processes, and burning destroys the natural habitats of of fossil fuels plants and animals. It can combine with nitrogen dioxide to form sulphuric acid (acid rain). Nitrogen dioxide Produced due to high-temperature It contributes to acid rain. It combustion (thunderstorms and irritatesthe eyes and its prolonged electric discharge), burning of fossil exposure causes respiratory fuels in motors’ exhausts, cigarette problems. smoke butane, and kerosene stoves Carbon monoxide A non-irritating but highly toxic gas It creates smog in the air, which is produced through partial oxidation responsible for several lung ailments. (when there is not enough oxygen It is the most fatal air poisoning gas, as to produce carbon dioxide) in it combines with hemoglobin to cases, such as the burning of stoves produce carboxyhemoglobin, which in a confined space (indoors) makes it unable to transfer oxygen in the body. Volatile Organic Fossil fuels, paints and coatings, VOCs are greenhouse gases Compounds (VOC), and chlorofluorocarbons in cleaning contributing to global warming. Non- which can be methane products and refrigerants methane VOCs, such as benzene, or non-methane toluene, and xylenes can cause cancer on prolonged exposure. Particulates (fine Natural causes include volcanic Increased concentrations of particles of solid/ eruptions, dust storms, forest fires, particulates can lead to heart disease, liquid suspended in vegetation, and sea spray changed lung function, and lung gas) Manmade causes include the cancer. burning of fossil fuels, power plants, industrial processes, and burning of agricultural wastes Chlorofluorocarbons Emitted from air conditioners, These mix with other gases in the (CFCs) refrigerators, and aerosol sprays stratosphere and damage the atmospheric ozone layer. The resulting ozone hole allows harmful ultraviolet rays from the sun to reach the earth’s surface, causing skin cancer, eye diseases, and plant damage. Ammonia Emitted from agricultural wastes It can increase the concentration of particulate matter after reacting with nitrous and sulfur oxide. Sources of air pollution The top five sources of air pollution are: 1 Households: The main source of air pollution is the burning of wood and fossil fuels in confined, indoor areas for cooking, heating, and lighting purposes. Other biomass-based fuels used for the same purposes also contribute to indoor pollution. To reduce household pollution, cleaner and more modern stoves must be used for cooking, heating, and lighting purposes. In 97 countries (out of 193), 85% of households have switched to cleaner fuels, but 3 billion people still use solid fuels for domesticpurposes. 2 Industries: The second biggest contributor to air pollution is industries withcoal- fuelledanddieselgenerators.Toreduceairpollution,industriesmustswitchover to renewable sources of energy production and increase energyefficiency. 3 Transport: Almost 1/4thof carbon dioxide emissions are due to vehicular emissions. Vehicles with diesel engines are the main culprits causing 200,000 premature deaths. People living in close vicinity to traffic zones are 12% more likelytohavedementia.Toreducevehicleemissions,policiesandprogramsmust be implemented to switch over to cleaner fuels and advanced emissionstandards. 4 Agriculture: Livestock farming, rice paddies and burning of agricultural waste produce methane and ammonia. Methane forms ground-level ozone which causes respiratory problems, such as asthma. It is also a stronger greenhouse gas contributing 34 times more to global warming than carbon dioxide. An effective mitigation step is to switch to a plant-based diet and reduce foodwastage. Farmers can reduce the production of methane from livestock farming by optimizing the digestibility of food and improving grazingpractices. 5 Waste: 40% of waste is openly burned around the world, more so in the urban areas of developing countries. This practice releases poisonous gases, such as methane and black carbon, into the atmosphere. To prevent this, the collection, separation, and disposal of solid waste must be improved. This will reduce the quantity of waste, which is to be burned or filled in landfills. Another advantage ofwasteseparationisthatitcanbeconvertedintocompost,whichisanalternative source of energy. Effects of air pollution 9 out of 10 people in the world today are inhaling the polluted air. Its effects are alarming, which include: Respiratory and heart problems: Air pollution is responsible for respiratory problems, heart diseases, and lung ailments including cancer. Each year, the deaths caused due to air pollution are 3 times more than those caused bymalaria, tuberculosis, and AIDS combined. The distribution of the causes of deaths due to air pollution is depicted in Figure: Ischemic heart Lung cancer, disease, 26% 29% Strokes, 24% Chronic obstructive pulmonary disease, 43% Causes of Deaths Due to Air Pollution Air pollution is even more dangerous to children, causing health problems, such as: o Low birth weight o Pneumonia o Asthma o Childhood cancers o Obesity o Poor lung development o Autism Global warming: Air pollution increases the concentration of greenhouse gasesin the atmosphere, which leads to global warming. Global warming is the phenomenon in which the surface temperature of the earth is quickly elevated due to greenhouse gases. Let us understand this concept. The temperature of the earth is controlled by the sun. About 30% of the sunlight coming to the earth is reflected by bright surfaces on the earth, such as ice and clouds. The remaining 70% of sunlight is absorbed by the land, oceans, and atmosphere, which heats the planet. As the planet warms up, rocks, air, and oceans radiate thermal infrared radiation (or heat energy). This radiation is absorbed in the atmosphere by water vapor and greenhouse gases, such as carbon dioxide and methane. The molecules radiate the energy back to the earth, heating the surface. Since the industrial revolution (past 250 years), the burning of fossil fuels and deforestation have increased the levels of greenhouse gases (carbon dioxide by 38% and methane by 148%). Consequently, the earth’s atmosphere has more greenhouse gas molecules which are absorbing more of the released infrared radiation fromthe Earth’s surface. Consequently, the temperature of the earth is rising. This is the enhanced greenhouse effect. Due to this effect, the average surface temperature of the earth has increased from 0.6° (1906) to 0.9 degrees celsius (2005). An even more alarming concern is that the rate of increase in temperature has almost doubled during the last 50 years. The graphical representation of the rising global average surface temperature is illustrated in Figure: Global Mean Surface Temperature 0.6 Annual mean Temperature Anomaly (°C) 5–year running mean 0.4 uncertainty 0.2 0 –0.2 1940 1960 1980 2000 Year –0.4 Rising Global AverageSurfaceTemperature 1880 1900 1920 Source: https://www.earthobservatory.nasa.gov/features/GlobalWarming/page2.php Due to the rising surface temperature worldwide, the polar ice caps will melt and the sea levels will rise. This may destroy the natural habitats of animals and plants and drown many major cities and islands. The following are consequences of rising surface temperatures: Acid rain: Vehicular and industrial emissions release harmful sulfur dioxide and nitrogen dioxide. When it rains, these gases can combine with water drops to make sulphuric acid. This acid rain destroys plants and animals. Eutrophication: Higher concentrated levels of nitrogen above the sea surface will make algae grow. These harmful algae destroy species of fish, animals, and plants. Loss of wildlife: Air pollution may cause wild animals to change their natural habitats, which in turn may threaten their survival. Ozone layer depletion: The ozone hole over Antarctica is increasing due to the presence of chlorofluorocarbons and hydrochlorofluorocarbons in the atmosphere. Consequently, the harmful ultraviolet rays enter the earth’s atmosphere. These UV rays can cause skin and eye problems, as well as damage crops. Preventive Measures 97% of cities in developing countries with a population of more than 1 million falls short of the WHO prescribed air quality levels. On the other hand, 29% of cities in developed countries also do not meet the minimum air quality levels. Under the 2015 Paris Agreement, 174 countries pledged to keep global warming below 2 degrees Celsius. The most effective way to do so is to cut down on air pollution. Not only will this save millions of lives, but it will also save costs in public health spending. Some preventive measures to control air pollution include: To use more public modes of transportation To replace petrol and diesel running vehicles with electric vehicles (however, electric vehicles also cause air pollution due to rubber tires) To generate power using nuclear and renewable sources of energy To switch over to cleaner fuels such as natural gas To implementing the 3 Rs – Reduce, Reuse and Recycle To use energy-efficient devices To ensure houses are well-ventilated To clean buildings regularly to avoid build-up of dust and mold To remove pollutants, such as aerosols and stringent cleaning supplies To use biodigesters to curb the burning of wastes. 2.2.2 WATER POLLUTION Water is also known as the universal solvent as it dissolves substances in if in comparison to other liquids. Water pollution happens when pernicious substances such as chemicals or microorganisms enter streams, rivers, lakes, oceans, aquifer, or other water bodies, and harm the quality of water. Water pollution is shown in pictorial representation in Figure : Water Pollution in Ganga Source: https://www.businessinsider.in/See-photos-of-the-devastating-pollution-in-Indias- holy-Ganges-River/ articleshow/62684561.cms The contamination of water bodies, such as rivers, lakes, seas, and groundwater,by chemicals and microorganisms, is called water pollution. It lowers the qualityof water making it unfit for human use. In 2015, about 1.8 million people in the world died due to water pollution-related causes (Lancet). India and China have the highest levels of water pollution. In India, about 580 people die of waterborne diseases every day. Types of Water Pollution There are two types of water pollution: Surface water pollution: This includes water pollution of rivers, lakes, and oceans. The pollution of oceans and seas is called marine pollution (discussed in a later section). The main causes of surface water pollution are the runoff of waste and fertilizers from farms, discharge of municipal and industrial wastes, and direct dumping of wastes into water bodies Groundwater pollution: This pollution is caused when pollutants (such as pesticides, fertilizers, waste leached from landfills and septic systems, arsenic, fluoride, pathogens, nitrates, pharmaceuticals, etc.) make their way into an aquifer, making the groundwater unfit for use. An aquifer, once polluted, becomes unfit for human use for decades. The polluted water from the ground can cause widespread poisoning or diseases. It is almost impossible and very expensive to remove contaminants from polluted groundwater. There are various sources of groundwater pollution, including: o Landfills o Onsite sanitation systems o Waste and wastewater treatment plants o Leakage from sewers o Spills in petrol filling stations o Overuse of fertilizers and pesticides in agricultural farms Cause of Water Pollution The following are some causes of water pollution: Agriculture: The agriculture sector is the biggest consumer of freshwater (70%). However, it is also a major cause of water pollution. During rains, the agricultural wastes, fertilizers, pesticides, and animal wastes runoff from farms into waterways. Rains can also runoff nutrients and pathogens from livestock operations into freshwater bodies. This type of pollution is called nutrient pollution, as it is caused by the excess of nutrients and phosphorus in the water. When nutrient water runs off into waterways, it increases the population of blue-green algae, which can cover the entire water body. This is called the harmful algae bloom. It depletes dissolved oxygen and kills aquatic species, making the water body a dead zone. Algae bloom is depicted in Figure: Algae Bloom in a Lake Source: https://www.nrdc.org/stories/water-pollution-everything-you-need-know Sewage: Overpopulation of the planet has also brought a crisis of dumping of sewage wastes. About 30% of the world’s population does not have proper sanitation facilities. Due to inadequate sewage disposal faci

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