BACHLEOR OF SCIENCE TRAVEL AND TOURISM MANAGEMENT SEMESTER III ENVIRONMENT, WASTE AND DISASTER MANAGEMENT BMS101
CHANDIGARH UNIVERSITY Institute of Distance and Online Learning Course Development Committee Prof. (Dr.) R.S.Bawa Pro Chancellor, Chandigarh University, Gharuan, Punjab Advisors Prof. (Dr.) Bharat Bhushan, Director – IGNOU Prof. (Dr.) Majulika Srivastava, Director – CIQA, IGNOU Programme Coordinators & Editing Team Master of Business Administration (MBA) Bachelor of Business Administration (BBA) Coordinator – Dr. Rupali Arora Coordinator – Dr. Simran Jewandah Master of Computer Applications (MCA) Bachelor of Computer Applications (BCA) Coordinator – Dr. Raju Kumar Coordinator – Dr. Manisha Malhotra Master of Commerce (M.Com.) Bachelor of Commerce (B.Com.) Coordinator – Dr. Aman Jindal Coordinator – Dr. Minakshi Garg Master of Arts (Psychology) Bachelor of Science (Travel &TourismManagement) Coordinator – Dr. Samerjeet Kaur Coordinator – Dr. Shikha Sharma Master of Arts (English) Bachelor of Arts (General) Coordinator – Dr. Ashita Chadha Coordinator – Ms. Neeraj Gohlan Academic and Administrative Management Prof. (Dr.) R. M. Bhagat Prof. (Dr.) S.S. Sehgal Executive Director – Sciences Registrar Prof. (Dr.) Manaswini Acharya Prof. (Dr.) Gurpreet Singh Executive Director – Liberal Arts Director – IDOL © No part of this publication should be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording and/or otherwise without the prior written permission of the authors and the publisher. SLM SPECIALLY PREPARED FOR CU IDOL STUDENTS Printed and Published by: TeamLease EdtechLimited www.teamleaseedtech.com CONTACT NO:01133002345 For: CHANDIGARH UNIVERSITY 2 Institute of Distance and Online Learning First Published in 2021 CU IDOL SELF LEARNING MATERIAL (SLM)
All rights reserved. No Part of this book may be reproduced or transmitted, in any form or by any means, without permission in writing from Chandigarh University. Any person who does any unauthorized act in relation to this book may be liable to criminal prosecution and civil claims for damages. This book is meant for educational and learning purpose. The author of the book has/have taken all reasonable care to ensure that the contents of the book do not violate any existing copyright or other intellectual property rights of any person in any manner whatsoever. In the event the Authors has/ have been unable to track any source and if any copyright has been inadvertently infringed, please notify the publisher in writing for corrective action. 3 CU IDOL SELF LEARNING MATERIAL (SLM)
CONTENTS Unit 1: General Introduction........................................................................................................5 Unit-2: Renewable And Non-Renewable Resources ..................................................................34 Unit 3– Environmental Pollution And Their Effects ..................................................................60 Unit-4: Disaster Management....................................................................................................94 Unit 5: Man Made Disasters ....................................................................................................113 Unit-6: Disaster Preparedness And Response Preparedness .....................................................175 Unit-7: Role Of Different Agencies In Disaster Management ..................................................192 Unit-8: Waste Management.....................................................................................................207 Unit 9- Waste Disposal ...........................................................................................................226 Unit-10 Recovery Of Biological Conversion Products.............................................................240 Unit 11- Solid Waste Management Act ...................................................................................261 4 CU IDOL SELF LEARNING MATERIAL (SLM)
UNIT 1: GENERAL INTRODUCTION Structure 1.0Learning Objectives 1.1Introduction 1.2Definition - Environment 1.2.1 Scope & Importance 1.2.2 Need for Public Awareness 1.3Ecosystem 1.3.1 Type of Ecosystem 1.3.2 Balanced Ecosystem 1.4Human Activities 1.5Food, Shelter, Economic and Social Security 1.6Effect of human activities on environment 1.6.1 Agriculture 1.6.2 Housing 1.6.3 Industry 1.6.4 Mining 1.6.5 Transportation activities 1.7Biodiversity & its conservation 1.8 Summary 1.9Keywords 1.10Learning Activity 1.11 Unit End Questions 1.12References 1.0 LEARNING OBJECTIVES After Studying this unit students will be able to: Acquire basic understanding of the total environment and associated problems. Develop a sense of responsibility and a strong feeling of concern for the environment. 1.1 INTRODUCTION Our earth supports millions of different kinds of living beings in an extremely wide variety of habitats The existence of all living beings on earth including the human race depends completely on the sun and the earth 5 CU IDOL SELF LEARNING MATERIAL (SLM)
Light emanating from the sun is an incessant source of radiant energy which is used in various ways on the earth to support life For example, the visible light is used in food production by the plants. A portion of solar radiation generates heat and keeps earth temperature optimum for the living organisms. The earth provides the substratum nourishment and the surroundings where the organisms live and carry out life activities In recent times, explosive human population growth and expanding energy use are leading to rapid detrimental changes in environment—creating virtually an environmental crisis We seem to have approached a level where survival and sustainability of life on this planet is threatened and therefore focus on equitableresolution of environmental issues is finding support from all across the globe There is a need for understanding the anthropogenic (human-induced)environmental changes at local, regional and global levels Most of the criticalenvironmental problems, be it loss of biodiversity or climate change, populationgrowth or pollution increase etc, fall within the framework of ecological studiesand require a thorough understanding of ecological principles for their resolution. 1.2DEFINITION – ENVIRONMENT The term environment is derived from the French word “environner” which means surrounding Environment is everything that is external to an organism It may be defined as the sum total of all social, economic, physical, chemical and biological factors which constitute the surroundings of humans or other life forms It is defined as the sum total of influences which modify and determine the development of life and its characteristics 1.2.1 SCOPE & IMPORTANCE The need to cultivate sound and well-organized interest in environment and to incorporate environmental education at all levels has been recognized Environmental education shall help arouse social consciousness and make the community aware of the fact that the good of the individual and that of the community are both harmed by ecological disruptions The chief aim of environmental education is that individual and social groups should acquire awareness and knowledge, develop attitudes, skills and abilities and participate in solving real life environmental problems The perspective should be integrated, inter-disciplinary and holistic in nature. 6 CU IDOL SELF LEARNING MATERIAL (SLM)
It must be appreciated that people’s active participation in environmental management is a must, otherwise no government alone can manage the issues howsoever good its policies may be. 1.2.2 NEED FOR PUBLIC AWARENESS Environment awareness is the base for environmental literacy, environmental education, environmental issues and environmental programs It is the first step of the ladder to the environmental security for sustainable development Environment is closely linked to human beings and hence influences their health and quality of life Improving our environment by environmental awareness and education will improve the human health and wellbeing of all Environmental awareness leads to understanding of environmental issues It helps implementation of environmental programs It creates concern about environmental impact on flora and fauna and wellbeing of man as well It forms sink of environmentally aware people 1.3 ECOSYSTEM An ecosystem is a biotic assemblage of plants, animals, and microbes, taken together with their physico-chemical environment An ecosystem may be defined as a self-sustained community of plants and animals existing in its own environment In an ecosystem the biological cycling of materials is maintained by three groups viz. producers, consumers and decomposers STRUCTURE OF AN ECOSYSTEM The biotic and abiotic components of an ecosystem constitute the structure of the ecosystem. Abiotic or Non-Living Components Climatic condition and physical factors Inorganic substances Organic substances Biotic or Living Components 7 Autotrophic component – Photoautotrophs, Chemoautotrophs Heterotrophic component – Macroconsumers, Microconsumers CU IDOL SELF LEARNING MATERIAL (SLM)
FUNCTION OF AN ECOSYSTEM It deals with energy flow and material flow through an ecosystem Fig 1.1 Function of An Ecosystem Energy Flow Biological activity involves utilization of energy. Energy is obtained from the sun and is transformed from radiant form to chemical form by photosynthesis and from chemical form to mechanical form during mechanical activity The flow of energy is always unidirectional Energy flow in ecosystems follows two laws of thermodynamics: The first law states that energy can neither be created nor destroyed but can only be transformed from one form to another The second law of thermodynamics states that no energy transformations are 100% efficient Energy flows through an ecosystem in the form of carbon–carbon bonds within organic compounds These bonds are broken during respiration when carbon joins with oxygen to produce carbon dioxide Respiration releases energy that is either used by organisms (life processes) or is lost as heat 8 CU IDOL SELF LEARNING MATERIAL (SLM)
The origin of all the energy in an ecosystem is the sun and the fate of the energy is eventually to be released as heat Material Flow Unlike energy, matter cycles through the system as minerals. Plants absorb mineral nutrients from the soil. These nutrients are combined into cells Consumers eat plants and other consumers ingest the minerals they contain and re- combining them in cells Eventually decomposers break down dead organic matter and then return the minerals to the soil These minerals may be taken out of the soil quickly by plants or can eventually through geological processes become locked within rocks until erosion eventually returns them to new soil Food Chain • A food chain is a food pathway that links different species in a community. In a food chain, energy and nutrients are passed from one organism to another. • The sequence of organism, each of which is a source of food for the next is called a food chain. • The sequence of eating and being eaten in an ecosystem is known as food chain • Types of Food Chain: Grazing food chain extends from producers through herbivores to carnivores. Detritus food chain starts with dead organic matter and passes through detritus feeding organisms in soil to organisms feeding on detritus feeders and their predators Trophic level • In a food chain, each stage of transfer of food energy is known as trophic level • It is defined as the number of links by which it is separated from the producer or as the nth position of the organism in the food chain • Trophic level corresponds to the different levels or steps in the food chain. In other words, the producers, the consumers, and the decomposers are the main trophic levels. Food Web • The interlocking patterns formed by several food chains that are linked together are called food webs (Or) Different food chains often interconnect to form a large network, called a food web. 9 CU IDOL SELF LEARNING MATERIAL (SLM)
• It allows an organism to obtain its food from two or more types of organisms of the lower trophic levels Significance of food chains and food webs Energy flow and nutrient cycling takes place in an ecosystem It helps to maintain the ecological balance Food chains show a unique property of biological magnification of certain chemicals Ecological Pyramids An ecological pyramid is a graphical representation of an ecological parameter like number of individuals or amount of biomass or amount of energy present in various trophic levels of a food chain with producer forming the base and top carnivores the tip. It may be upright or inverted or spindle shaped Types of Ecological Pyramids Pyramid of Numbers A graphical representation of number of individuals per unit area of various trophic level stepwise with the producers forming the base and top carnivores the tip, is called pyramid of numbers It can be upright or inverted Pyramid of Biomass A graphical representation of biomass present sequence wise per unit area of different trophic levels with the producers forming the base and top carnivores the tip, is called pyramid of biomass It can be upright or inverted Pyramid of Energy A graphical representation of the amount of energy trapped per unit time and area in various trophic levels of a food chain with the producers forming the base and top carnivores the tip, is called pyramid of energy Always upright 1.3.1 Types of Ecosystem 10 Ecosystems are classified on the basis of nature, duration and size CU IDOL SELF LEARNING MATERIAL (SLM)
On the basis of nature: Natural Ecosystem Artificial Ecosystem On the basis of duration: Temporary Ecosystem Permanent Ecosystem On the basis of size: Large Ecosystem Tiny Ecosystem Natural Ecosystems An ecosystem that is developed under natural conditions is called a natural ecosystem Natural ecosystems operate by themselves under natural conditions without interference by humans Natural ecosystems can be terrestrial as well as aquatic E.g., Grassland, Pond, Lake Terrestrial Ecosystems: Forest ecosystems, Grassland ecosystems, Desert ecosystem Aquatic Ecosystems:Fresh water ecosystems - Lotic (Running) and Lentic (Standing), Marine ecosystems Artificial Ecosystems These are maintained by man and hence are also termed as Man-made or Man- Engineered Ecosystem Artificial ecosystems are maintained by human beings. In these, natural balance is disturbed regularly. In artificial ecosystems, humans try to control the biological and physiological properties of the ecosystem. E.g.,Cropland, Orchard, Garden, Aquarium 11 CU IDOL SELF LEARNING MATERIAL (SLM)
Fig 1.2 Types of Ecosystem Natural Ecosystem Artificial Ecosystem Natural ecosystems are developed Artificial ecosystems are created and under natural conditions manipulated by human activities In natural ecosystems, plants of one In artificial ecosystems, plants of same species are scattered species grow in close proximity Natural ecosystems usually have Artificial ecosystems usually contain alternate sources of food fewer food choices In natural ecosystems, inorganic In artificial ecosystems, inorganic nutrients are returned to the soil from nutrients do not return to the soil but are which they were taken carried away to other places Natural ecosystems have no distinct Artificial ecosystems have distinct boundaries boundaries Table 1.1 Natural and Artificial Ecosystem 12 CU IDOL SELF LEARNING MATERIAL (SLM)
Temporary Ecosystems These are short lived ecosystems which may be natural or man-made E.g., Rainfed pond, Laboratory culture of protozoans Permanent Ecosystems These are self-supporting natural ecosystems that maintain themselves for relatively long duration E.g., Lake, Forest, Desert Small Ecosystems Small sized ecosystems are also termed as Micro-ecosystems E.g., Flowerpot, site under a stone Large Ecosystems Very large sized ecosystems are also termed as Macro-ecosystems E.g., Ocean, Forest, Desert 1.3.2 Balanced Ecosystem A balanced ecosystem signifies a habitat which is sustainable It consists of animals, plants, microorganisms and more which depend on each other and their surroundings These ecosystems exhibit resourceful energy and material cycling It also displays interconnectedness amid primary producers and predators In a balanced ecosystem, the community of living (biotic) organisms interacts with non-living (abiotic) features in the environment. Abiotic features of ecosystems include precipitation, temperature, landscape, sunlight, soil or water chemistry, and moisture The types of biotic factors in a balanced ecosystem include primary producers such as plants, primary consumers such as herbivores, secondary consumers such as carnivores, consumers such as omnivores that consume both plants and animals, and detritivores that eat decaying organic matter. Biotic factors rely upon abiotic factors to survive. Plants require certain temperature, moisture and soil chemistry to thrive. Animals rely on those plants for their food. Anything affecting any factor of an ecosystem can throw it off balance and force organisms to adapt or die off. 13 CU IDOL SELF LEARNING MATERIAL (SLM)
1.4 HUMAN ACTIVITIES Human activities are the various actions for recreation, living, or necessity done by people. For instance it includes leisure, entertainment, industry, recreation, war, and exercise. 1.5 FOOD, SHELTER, ECONOMIC AND SOCIAL SECURITY Food security, as defined by the United Nations' Committee on World Food Security, means that all people, at all times, have physical, social, and economic access to sufficient, safe, and nutritious food that meets their food preferences and dietary needs for an active and healthy life. Shelter Security: The UN Special Rapporteur on adequate housing has defined the human right to adequate housing, as: “The right of every woman, man, youth and child to gain and sustain a safe and secure home and community in which to live in peace and dignity.” Economic Security or Financial Security is the condition of having stable income or other resources to support a standard of living now and in the foreseeable future. Social Security is the protection that a society provides to individuals and households to ensure access to health care and to guarantee income security, particularly in cases of old age, unemployment, sickness, invalidity, work injury, maternity or loss of a breadwinner. 1.6 EFFECT OF HUMAN ACTIVITIES ON ENVIRONMENT Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water. These negative impacts can affect human behavior and can prompt mass migrations or battles over clean water. 1.6.1 Agriculture • Agriculture contributes to a number larger of environmental issues that cause environmental degradation including: climate change, deforestation, biodiversity loss, dead zones, genetic engineering, irrigation problems, pollutants, soil degradation, and waste. • The five main impacts of agriculture on environment are: Degradation of Land 14 CU IDOL SELF LEARNING MATERIAL (SLM)
Deforestation Biodiversity Pest Problem Disposal of Industrial & Agricultural Wastes • Degradation of land: The degradation of land in one form or the other is matter of serious concern endangering sustainability of agriculture. Landslides caused by rains and flowing water in hilly areas and deforestation, overgrazing and faulty cultural practices in the forest and other plain areas expose the soil to water and wind erosions. The degradation of land is due to: Deficiency of soil nutrients due to intensive cultivation. Imbalance in soil nutrients particularly the deficiency of micro- nutrients. Decline in the organic matter in the soil. Deforestation and overgrazing of Pasteur’s causing exposure of soil to water and wind erosion. Decline in underground water due to over exhaustion for high water using crops, increase in cropping intensity and increase in cultivated area especially is northern part of the sweet water zone. Increase in water level in the cotton belt of north-western part of the country endangering then cultivation of cotton crop due to pumping out of brackish water resulting in accumulation of salts on earth surface. Further, the wet condition due to non-percolation of rain water attracts serious pests. High uses of nitrogen and water have caused percolation of nitrogen up to water table thus polluting it even for human consumption. • Deforestation The main reasons for decline in forest wealth are: Increase in population resulting in more demand for fuel wood and timber. Indiscriminate siting of development projects Forest fires The forest area in the recent past has not changed much because its diversion for non-forestry purposes has been more or less compensated by afforestation • Biodiversity 15 CU IDOL SELF LEARNING MATERIAL (SLM)
India is a country with wide variety of agro-climatic conditions which harbour a wide variety of animals and plants. According to an estimate, India ranks 10th in the World and 4th in Asia in terms of plant diversity. As agriculture is becoming more and more commercialized, a number of plant and animal species are becoming extinct. The crops showing high profits are covering more area while the less profitable ones are rapidly declining, creating a number of environmental problems. The depletion of vegetative cover such as grass lands and forest tree species and similarly extinction of wild animals, birds and insects is matter of concern. According to another estimate, over 1,500 plant species, 79 mammals, 44 birds, 15 reptiles, 3 amphibians and several insects are listed as endangered. • Pest Problem With the shift in crop pattern, increase in area under irrigation and higher cropping intensity, the pest problem has become very severe. The seriousness of pests has further increased by way of indiscriminate and increased use of pesticides. The predatory birds and insect population has dwindled at a sharp rate causing lack of natural control of pests. The direct effect of high use of dangerous pesticides is on human and animal health. A large variety of cases of residual effect of pesticides and intake by human and animals have created health hazards. • Disposal of Industrial & Agricultural Waste The use of by-products such as paddy straw and rice husk has not been made properly. The burning of such by-products creates increase in carbon dioxide and carbon-monoxide in the atmosphere resulting in respiratory problems for animals and human beings. There is need for recycling the agricultural wastes by having enterprises like dairy, poultry, fishery etc., processing of by-products and ploughing in the field as organic matter. 16 CU IDOL SELF LEARNING MATERIAL (SLM)
1.6.2 HOUSING The primary cause of the global biodiversity crisis is human-induced alteration and loss of natural habitats. One of the most important causes of habitat destruction is housing growth, manifested both in rural and urban sprawl. The impacts of housing growth derive from both building human dwellings and their associated infrastructure such as roads. The threats to biodiversity include not only habitat lost directly to roads or houses, but the effects these human disturbances have on the larger landscape. Housing development increases impervious surfaces and the risk of fire, spreads pollutants, and changes nutrient and biogeochemical cycles. All these impacts are exacerbated by residents’ activities such as landscaping, introduction of non-native (sometimes invasive) species, and support for domestic predators. Changing land use and removing the natural land cover introduces new barriers to wildlife movements. In this newly fragmented landscape, the remaining natural fragments are often too small to sustain viable populations of native species, while housing growth favors “human adapted” synanthropic species. As a result, native wildlife typically decreases in abundance and richness. Increased housing development can impact the public's access to forest lands, increase wildfire ignitions and management costs, reduce water quality, and introduce insects and diseases. 1.6.3 INDUSTRY Industrialization contributes major part for the economic development and prosperity of a country. On one hand it provides employment opportunities and wealth generation while on other hand it leads to following environmental deterioration. It leads to the depletion of natural resources. It leads to air pollution, water pollution and soil pollution. Global warming, climatic changes are the major consequences of industrialization. It causes acid rain. It leads to the degradation of land quality. It leads to the generation of hazardous waste whose safe disposal becomes a big problem. These industries are responsible for the following adverse diseases and ill effect like silicosis and pneumoconiosis, tuberculosis, skin diseases and deafness. 17 CU IDOL SELF LEARNING MATERIAL (SLM)
Metallic contaminant like Cd, Zn, Hg etc., destroy bacteria and beneficial microorganisms in the soil. Industrial wastes including toxins enter in the food chain causes number of undesirable effects to living beings and animals. Industrial effluent damages the natural biological purification mechanism of sewage treatment causing several soil and water borne diseases. 1.6.4 MINING • Mining activities, including prospecting, exploration, construction, operation, maintenance, expansion, abandonment, decommissioning and repurposing of a mine can impact social and environmental systems in a range of positive and negative, and direct and indirect ways. • Mine exploration, construction, operation, and maintenance may result in land-use change, and may have associated negative impacts on environments, including deforestation, erosion, contamination and alteration of soil profiles, contamination of local streams and wetlands, and an increase in noise level, dust and emissions. • Mine abandonment, decommissioning and repurposing may also result in similar significant environmental impacts, such as soil and water contamination. • Beyond the mines themselves, infrastructure built to support mining activities, such as roads, ports, railway tracks, and power lines, can affect migratory routes of animals and increase habitat fragmentation. • Mining can also have positive and negative impacts on humans and societies. Negative impacts include those on human health and living standards, for example. Mining is also known to affect traditional practices of Indigenous peoples living in nearby communities, and conflicts in land use are also often present, as are other social impacts including those related to public health and human wellbeing. • In terms of positive impacts, mining is often a source of local employment and may contribute to local and regional economies. • Remediation of the potential environmental impacts, for example through water treatment and ecological restoration, can have positive net effects on environmental systems. • Mine abandonment, decommissioning and repurposing can also have both positive and negative social impacts. Examples of negative impacts include loss of jobs and local identities, while positive impact can include opportunities for new economic activities, e.g., in the repurposing of mines to become tourist attractions. 18 CU IDOL SELF LEARNING MATERIAL (SLM)
1.6.5 TRANSPORTATION ACTIVITIES The issue of transportation and the environment is paradoxical since transportation conveys substantial socioeconomic benefits, but at the same time, transportation is impacting environmental systems. Further, environmental conditions impact transportation systems in terms of operating conditions and infrastructure requirements such as construction and maintenance. The growth of passenger and freight mobility has expanded the role of transportation as a source of emission of pollutants and their multiple impacts on the environment. These impacts fall within three categories: Direct Impacts The immediate consequence of transport activities on the environment where the cause-and-effect relationship are generally clear and well understood. For instance, noise and carbon monoxide emissions are known to have direct harmful effects. Indirect Impacts The secondary (or tertiary) effects of transport activities on environmental systems are often of a higher consequence than direct impacts, but the involved relationships are often misunderstood and more challenging to establish. For instance, particulates, which are mostly the outcome of incomplete combustion in an internal combustion engine, are indirectly linked with respiratory and cardiovascular problems since they contribute, among other factors, to such conditions. Cumulative Impacts The additive, multiplicative or synergetic consequences of transport activities are known as cumulative impacts. They consider the varied effects of direct and indirect impacts on an ecosystem, which are often unpredictable. Climate change, with complex causes and consequences, is the cumulative impact of several natural and anthropogenic factors, in which transportation plays a role. The share of transportation in global CO2 emissions is increasing. 22% of global CO2 emissions are attributed to the transport sector, with this share is around 25% for advanced economies such as the United States. 19 CU IDOL SELF LEARNING MATERIAL (SLM)
1.7 BIODIVERSITY & ITS CONSERVATION Biological diversity or biodiversity refers to the variety of life forms: the different plants, animals and microorganisms, the genes they contain, and the ecosystems they form Levels of Biodiversity Biological diversity includes three hierarchical levels: Genetic diversity, Species diversity, and Community and Ecosystem diversity. These levels of biodiversity are interrelated, yet distinct enough to be studied separately to understand the interconnections that support life on earth. Genetic Diversity Genetic diversityrefers to the variety of genetic information contained in all of the individual plants, animals and microorganisms. Genetic diversity occurs within and between populations of species as well as between species Fig. 1.3 Genetic Diversity Species Diversity • Species diversityrefers to the variety of living species. • Simplest measure of species diversity is species richness, i.e., the number of species per unit area. 20 CU IDOL SELF LEARNING MATERIAL (SLM)
• The number of species increases with the area of the site. • Generally, greater the species richness greater is the species diversity. • However, number of individuals among the species may also vary resulting into differences in evenness, or equitability, and consequently in diversity. Fig.1.4 Species Diversity Ecosystem Diversity Ecosystem diversity relates to the variety of habitats, biotic communities, and ecological processes, as well as the tremendous diversity present within ecosystems in terms of habitat differences and the variety of ecological processes. Fig. 1.5 Ecosystem Diversity 21 CU IDOL SELF LEARNING MATERIAL (SLM)
Importance of Biodiversity Human beings are dependent for their sustenance, health, well-being and enjoyment of life on fundamental biological systems and processes. Humanity derives all of its food and many medicines and industrial products from the wild and domesticated components of biological diversity. Biotic resources also serve recreation and tourism, and underpin the ecosystems which provide us with many services Services provided by Biodiversity • Nutrient cycling: The movement of elements such as nitrogen, Sulphur and phosphorous between different forms as they pass through the food chain. The elements cycle between gas forms and compounds which are found in the soil and living organisms. • Primary production: The capturing of energy from the sun by plants and using this to convert carbon dioxide into organic compounds. • Maintaining the dynamic balance of nature’s complex systems: Habitats and all their constituent parts play an important role in regulating local and global climate patterns, soil formation, water purification and nutrient cycling and many other regulatory functions which help maintain the planet in a state which is self-sustaining. Values of Biodiversity Consumptive Use Value: Direct use values – biodiversity products are harvested and consumed directly • FOOD - 30,000 or more plant species have edible parts, 20 species feed the majority (90%) of the world's population; just 3 species are the major world-wide staples (rice, wheat, and corn). • DRUGS – 20,000 plant species are believed to be used medicinally; 70% of the modern medicines are derived from plant and plant extracts • FUEL – firewood, fossil fuels like coal, petroleum and natural gas. Productive Use Value: • Commercial value – the products derived from plants and animals are marketed and sold Animal Product Animal Silk Silk worm 22 CU IDOL SELF LEARNING MATERIAL (SLM)
Wool Sheep Tusk Elephants Leather All animals Food Fish and Animals Table 1.2 Animal Products Plant / Animal Product Industry Wood Paper and pulp industry, plywood industry, railway sleeper industry Cotton Textile Industry Fruits and Vegetables Food industry Leather Leather Industry Ivory Ivory Industry Table 1.3 Animal Products in Industries Social and Cultural Value: • It is associated with the social life, religion and spiritual aspects of the people • Human cultures co-evolve with their environment • Biodiversity has inspired musicians, painters, sculptors, writers and other artists. Many cultural groups view themselves as an integral part of the natural world and show respect for other living organisms. • Holy Plants – tulsi, peepal, lotus, neem, etc. • Holy Animals – Cow, snake, peacock,etc. Ethical Value: • All life must be preserved • Our rich heritage teaches us to worship plants, animals, rivers and mountains • A species may or may not be used but its existence in nature gives us pleasure Aesthetic Value: • Aesthetic values of our natural ecosystems and landscapes contribute to the emotional and spiritual wellbeing of a highly industrial population • Eco-tourism – spending time and money visiting beautiful places to enjoy the aesthetic value of biodiversity 23 CU IDOL SELF LEARNING MATERIAL (SLM)
Optional Value: • These are the potentials that are unknown and need to be known. • Important ecosystem services and uses for plants and animals are still unknown and await discovery. • As technology improves, new bioresources to increase human welfare will be discovered and developed THEATS TO BIODIVERSITY • The Earth is home to a tremendous biological diversity, or “biodiversity”, which includes: • The millions of different species • The diversity of their genes, physiologies, and behaviours • The multitude of their ecological interactions • The variety of the ecosystems they constitute • This biodiversity, which is the result of more than 3 billion years of evolution, is under serious threat today Threats • Habitat destruction and fragmentation • Habitat modification • Introduced species – non-native or exotic species • Over exploitation of natural resources • Unplannedand uncontrolled industrialization • Man-wildlife conflict • Inadequate knowledge of values about the species and ecosystem • Pollution and poisoning of ecosystem • Low priority for conservation of living natural resources • Increase of greenhouse gases and global warming • Improper use of agricultural chemicals and pesticides • Hunting and fishing • Forest fires, droughts, cyclones, diseases, landslides, etc. 24 CU IDOL SELF LEARNING MATERIAL (SLM)
Fig 1.6 Domino Effect: • Domino effects occur when the removal of one species (an extinction event) or the addition of one species (an invasion event) affects the entire biological system. • Domino effects are especially likely when two or more species are highly interdependent, or when the affected species is a \"keystone\" species, meaning that it has strong connections to many other species Keystone Species: • A keystone species is a species that plays a critical role in maintaining the structure of an ecological community and whose impact on the community is greater than would be expected based on its relative abundance or total biomass. • Bees: By pollinating plants, bees contribute to their survival. The plants are shelter for insects, which are then eaten by other species, like birds. • Beavers: Beavers are considered habitat engineers because they change the environment by building dams. This dam building provides still water in which many species flourish. 25 CU IDOL SELF LEARNING MATERIAL (SLM)
• Star fish:Star fish acts as keystone species by preying on sea urchins, mussels and other shell fish. If the star fish is removed, mussel population would explode and force other species out. Hotspots: Hotspots are regions that harbour a great diversity of endemic species and at the same time have been significantly impacted and altered by human activities. Hotspots are areas that are extremely rich in species, have high endemism and are under constant threat To qualify as hotspot a region must satisfy the following conditions: Must support 1500 endemic plant species, 0.5% of the global total Must have lost more than 70% of its original habitat Biodiversity Indices: Biodiversity indices are used for measuring biodiversity and can be expressed in numbers • Species richness – total number of species found in an environment • Simpson’s Index – is the probability that randomly selected individuals belong to two different species • Shannon- Wiener Index – measures the order or disorder of species in a particular system • Species Evenness – how similar the abundance of different species is in a community There are three other indices which are used by ecologists: • Alpha Diversity refers to diversity within a particular area, community or ecosystem, and is measured by counting the number of taxa within the ecosystem (usually species) • Beta diversity is species diversity between ecosystems; this involves comparing the number of taxa that are unique to each of the ecosystems. • Gamma diversity is a measure of the overall diversity for different ecosystems within a region. Some definitions: • Extinct - Species that are no longer known to exist in the wild, though it may survive in cultivation • Endangered – Taxa in danger of extinction and whose survival is unlikely if the causal factors continue operating • Vulnerable – Taxa likely to move into “Endangered” category in the future if the causal factors continue operating • Rare – Taxa with small world population but that are not at present endangered or vulnerable but are at risk 26 CU IDOL SELF LEARNING MATERIAL (SLM)
• Threatened – It is a general term to denote that they fall into any of the category - Extinct, Endangered, Vulnerable, Rare • Biodiversity hotspot – richness of species concentration at a particular region • Endemism - is the ecological state of being unique to a place • Red Data Book – the name given to the book dealing with threatened animals and plants of any region. • Green Book – the list of rare plants growing in protected area are given in it. • Blue Book – contains endangered species of the world. Biodiversity In India • Geographical Area – 32,87,591 square km • Seventh largest country of the world • Rich in biodiversity with a sizeable percentage of endemic flora and fauna • Total number of endemic plant species is 5150 and animals is 1837 • Has 8.1% of the world’s total biodiversity with a species count of about 0.13 million • Has two major realms – Palearctic and Indo-Malayan • Three biomes - Tropical humid forests, - Tropical dry /deciduous forests, - Warm desert/semi-deserts Biogeographical Classification of India • Trans Himalayan zone • Himalayan zone • Desert zone • Semi-arid zone • Western Ghats • Deccan Peninsula • Gangetic Plain • Northeast India • Coasts and Lakshadweep Islands • Andaman and Nicobar Islands 27 CU IDOL SELF LEARNING MATERIAL (SLM)
Fig. 1.7 Biogeographical Classification of India PROTECTION /RESTORATION OF BIODIVERSITY • Mitigate habitat fragmentation • Control non-native species • Manage for sustainability • Restore ecosystems • Protect endangered species • Protect ecosystems CONSERVATION OF BIODIVERSITY • Conservation is the protection, preservation, management, or restoration of wildlife and natural resources such as forests and water. • Through the conservation of biodiversity, the survival of many species and habitats which are threatened due to human activities can be ensured. • Other reasons for conserving biodiversity include securing valuable Natural Resources for future generations and protecting the wellbeing of eco-system functions. 28 CU IDOL SELF LEARNING MATERIAL (SLM)
• Conservation can broadly be divided into two types: • In-situ (On-site): Conservation of habitats, species and ecosystems where they naturally occur. This is in-situ conservation and the natural processes and interaction are conserved as well as the elements of biodiversity. National parks, wildlife sanctuaries, biosphere reserves are examples of in-situ conservation Advantages: • The species will have all the resources that it is adapted too. • In situ species will continue to evolve in their natural environment, captive organisms are buffered from environmental changes. • In situ species have more space. • Bigger breeding populations can be kept in situ. • It is cheaper to keep an organism in situ. Disadvantages: • It is difficult to control illegal exploitation (e.g., poaching) • The environment may need restoring and alien species are difficult to control. Ex situ conservation: Captive • In situ conservation projects require land and people which are limited resources in some regions of the world. • In situ conservation incurs the possible threat of disease eliminating whole, or substantial parts, of a conserved population • Ex-situ (Off-site): The conservation of elements of biodiversity out of the context of their natural habitats is referred to as ex-situ conservation. Zoos, botanical gardens and seed banks are all example of ex-situ conservation. Advantages: • Survival of endangered species is increasing due to special care and attention • In captive breeding, animals are assured food, water, shelter and also security and hence longer life span Disadvantages: • It is expensive method • The freedom of wildlife is lost • The animals cannot survive in natural environment 1.8 SUMMARY The term environment is derived from the French word “environner” which means surrounding. An ecosystem may be defined as a self-sustained community of plants and animals existing in its own environment 29 CU IDOL SELF LEARNING MATERIAL (SLM)
The biotic and abiotic components of an ecosystem constitute the structure of the ecosystem. Energy flows through an ecosystem in the form of carbon–carbon bonds within organic compounds. The sequence of organism, each of which is a source of food for the next is called a food chain. Trophic level is defined as the number of links by which it is separated from the producer or as the nth position of the organism in the food chain. The interlocking patterns formed by several food chains that are linked together are called food webs. An ecological pyramid is a graphical representation of an ecological parameter like number of individuals or amount of biomass or amount of energy present in various trophic levels of a food chain A balanced ecosystem signifies a habitat which is sustainable Economic Security or Financial Security is the condition of having stable income or other resources to support a standard of living now and in the foreseeable future. Social Security is the protection that a society provides to individuals and households to ensure access to health care and to guarantee income security, particularly in cases of old age, unemployment, sickness, invalidity, work injury, maternity or loss of a breadwinner. The primary cause of the global biodiversity crisis is human-induced alteration and loss of natural habitats. The growth of passenger and freight mobility has expanded the role of transportation as a source of emission of pollutants and their multiple impacts on the environment. Biological diversity or biodiversity refers to the variety of life forms: the different plants, animals and microorganisms, the genes they contain, and the ecosystems they form Genetic diversityrefers to the variety of genetic information contained in all of the individual plants, animals and microorganisms. Simplest measure of species diversity is species richness, i.e., the number of species per unit area. Domino effect occurs when the removal of one species (an extinction event) or the addition of one species (an invasion event) affects the entire biological system. A keystone species is a species that plays a critical role in maintaining the structure of an ecological community and whose impact on the community is greater than would be expected based on its relative abundance or total biomass. Hotspots are areas that are extremely rich in species, have high endemism and are under constant threat 30 CU IDOL SELF LEARNING MATERIAL (SLM)
Conservation is the protection, preservation, management, or restoration of wildlife and natural resources such as forests and water. 1.9KEYWORDS The term Environment is derived from the French word “environner” which means surrounding. An Ecosystem may be defined as a self-sustained community of plants and animals existing in its own environment. The sequence of organism, each of which is a source of food for the next is called a Food Chain The interlocking patterns formed by several food chains that are linked together are called Food Webs An Ecological Pyramid is a graphical representation of an ecological parameter like number of individuals or amount of biomass or amount of energy present in various trophic levels of a food chain Deforestationrefers to the decrease in forest areas across the world that are lost for other uses such as agricultural croplands, urbanization, or mining activities. • A Keystone Species is a species that plays a critical role in maintaining the structure of an ecological community and whose impact on the community is greater than would be expected based on its relative abundance or total biomass. Domino Effect occurs when the removal of one species (an extinction event) or the addition of one species (an invasion event) affects the entire biological system. Biological Diversity or Biodiversity refers to the variety of life forms: the different plants, animals and microorganisms, the genes they contain, and the ecosystems they form Hotspots are regions that harbour a great diversity of endemic species and at the same time have been significantly impacted and altered by human activities. Genetic Diversityrefers to the variety of genetic information contained in all of the individual plants, animals and microorganisms. 1.10 LEARNING ACTIVITY 1. Take a walk on the wild side with a guided nature tour. Identify inhabitants of the wild and discuss what would happen if their natural habitats were destroyed. After the activity, allow your group to brainstorm ideas for how humans can protect the land and animals around us. ___________________________________________________________________________ ___________________________________________________________________________ 31 CU IDOL SELF LEARNING MATERIAL (SLM)
1.11 UNIT END QUESTIONS A.Descriptive Questions Short Questions 1. Define environment. 2. Differentiate between food chain and food web. 3. What is a keystone species? 4. State a few impacts of housing on the environment. 5. List out the bio-geographical zones of India. Long Questions 1. Discuss the scope, importance and the need for public awareness on environment. 2. Compare and contrast the natural and artificial ecosystems with suitable examples. 3. Summarize the impact of human activities on environment. 4. Explain in brief, the present-day threats to biodiversity. 5. Write short notes on the conservation of biodiversity. B.Multiple Choice Questions 1. _______ may be defined as a self-sustained community of plants and animals existing in its own environment. a. Ecosystem b. Ecology c. Biome d. Biodiversity 2. A _______ is a graphical representation of an ecological parameter like number of individuals or amount of biomass or amount of energy present in various trophic levels. a. Food Chain b. Food Web c. Energy Flow d. Ecological Pyramid 3. The condition of having stable income or other resources to support a standard of living now and in the foreseeable future is known as a. Personal Security b. Economic Security c. Social Security d. Housing Security 32 CU IDOL SELF LEARNING MATERIAL (SLM)
4. Species that are in danger of extinction and whose survival is unlikely if the causal factors continue operating is known as a. Extinct Species b. Endangered Species c. Rare Species d. Vulnerable Species 5. _______ diversity is a measure of the overall diversity for different ecosystems within a region. a. Alpha b. Beta c. Gamma d. Delta Answer 1-a, 2-d, 3-b, 4-b, 5-c 1.12 REFERENCES Reference Books Erach Bharucha, “Textbook of Environmental Studies” University Press India Pvt. Ltd., Hyderabad, 2015. G. Tyler Miller, Jr. and Scott E. Spoolman “Environmental Science” Thirteenth Edition, Cengage Learning, 2010. Gilbert M. Masters and Wendell P. Ela “Introduction to Environmental Engineering and Science‟, 3rd edition, Pearson Education, 2013 Websites www.fao.org www.nationalgeographic.org www.transportgeography.org 33 CU IDOL SELF LEARNING MATERIAL (SLM)
UNIT-2: RENEWABLE AND NON-RENEWABLE RESOURCES Structure 2.0 Learning Objectives 2.1 Introduction 2.2 Natural Resources 2.3 Forest Resources 2.4 Water Resources 2.5 Mineral Resources 2.6 Land Resources 2.6.1 Availability and Quality Aspects 2.7 Energy Resources 2.7.1 Hydro Electric Energy 2.7.2 Nuclear Energy 2.7.3 Solar Energy 2.7.4 Hydrogen as an Alternative Source of Energy 2.7.5 Biomass and Biogas 2.8 Summary 2.9 Keywords 2.10 Learning Activity 2.11Unit end Questions 2.12 References 2.0 LEARNING OBJECTIVES After Studying this unit students will be able to: To impart knowledge on the various types of natural resources, their importance and the need to conserve and protect them. To facilitate the students to achieve a clear conceptual understanding of alternative sources of energy and their application. 2.1 INTRODUCTION Earth’s biosphere is endowed with extremely diverse kinds of environments which provide countless goods and services to human kind. Any component of the natural environment that 34 CU IDOL SELF LEARNING MATERIAL (SLM)
can be utilized by man to promote his welfare is considered as a natural resource. The natural resource can be a substance, an energy unit or a natural process or phenomenon. Land, soil, water, forests, grasslands, etc. are examples of important natural resources. Some of the resources (e.g., soil, water) are important components of the life-supporting system. Besides being source of food, fodder and shelter, natural resources also provide recreational opportunities, solace and even inspiration to mankind. Natural resources have been exploited by humans since the beginning of civilization or even before. However, since the resources were abundant then relative to human population, no significant depletion occurred. During the last millennia human population has increased considerably causing serious damage or destruction of natural resources. In this chapter we will study major kinds of natural resources, causes of their degradation and their conservation. 2.2 NATURAL RESOURCES Classification of Natural Resources Natural resources vary greatly in their location, quantity and quality. For instance, a particular forest type may occur only in certain countries. Also, the geographical area covered by forest and wood quality may differ widely in different countries. Some resources can be reused after being used once. A convenient classification of resources is based upon their exhaustibility and renewability (Fig. 2.1). Basically, resources can be categorized as Inexhaustible and Exhaustible. Natural Resources Inexhaustible Exhaustible Renewable Non Renewable Figure 2.1 Classification of Natural Resources Inexhaustible Resources Inexhaustible resources are available in unlimited quantities on the earth. While some inexhaustible resources remain virtually unaffected by human impact, many others may show some changes in their quality though their quantity may remain unchanged. Resources like solar energy, wind power, tide power, rainfall, and even atomic energy, cannot be exhausted 35 CU IDOL SELF LEARNING MATERIAL (SLM)
significantly at global level due to human activities. Such resources may sometime be locally affected by human activities; for example, pollution may change the quality of air. Exhaustible Resources A large number of natural resources are exhaustible, i.e., they have finite supply on the earth and can be exhausted if used indiscriminately. Broadly, the exhaustible resources can be either renewable or non-renewable. Renewable Resources Most of biotic resources are renewable. The growth and reproduction of such resources can be successfully managed so that these resources are continuously regenerated. However, if the consumption of these resources continues to exceed their rate of renewal not only their quality is affected, they may even get totally exhausted. Selected examples of ecosystems and their important renewable products are: Forests, which yield timber and other plant products Rangelands, which sustain grazing animals for milk, meat and wool production Wildlife, which maintain food chain Agricultural systems, which yield food and fiber, and Marine and fresh water systems, which yield foods from plants and animals Soil and water are other renewable resources. Non-Renewable Resources Some biotic resources are non-renewable, i.e., they cannot be regained or reconstructed once they are used up. Biological species, which have evolved in nature during the course millions of years, are considered non-renewable. Once a biological species becomes extinct from the earth, it cannot be recreated by man. Many abiotic resources are also non-renewable. For instance, fossil fuels (coal, petroleum and gas) and metals once extracted cannot be regenerated at the place of extraction. After unlimited extraction and use, the fossil fuels will certainly get exhausted. Principal Natural Resources Amongst the earth`s resources the following contribute significantly to human welfare: Forests Water Minerals Food Energy Land 36 CU IDOL SELF LEARNING MATERIAL (SLM)
2.3 FOREST RESOURCES Almost one-third of the earth's land is covered with forests and they play an important role in sustaining life. They house over 60% of the world's biodiversity and provide human beings with many products such as food, medicine, fuel, lumber, paper, etc. They also play very important ecological roles by stopping erosion, protecting the watershed, controlling stream and river flows, regulating atmospheric conditions, and preventing flooding and landslides. Forest Products and their Uses Timber Raw materials Edible products Contribution to national income Natural habitat Manure and fuel wood Medicinal plants Tourism Employment opportunities Commercial Uses of Forests Forests play a very important role in building the economy of a country. Forests are the main sources of timber for building, furniture, and firewood. Wood pulp is the primary source of raw material for the paper industry. Forests also provide the raw material for several industries like sports goods, and matches, etc. Many kinds of pharmaceuticals, rayon, and other useful materials like gums, resins and turpentine oil are made from the raw materials found in forests. Ecological Uses of Forests Forests serve many functions. Primarily, they protect and form natural resources. Through the process of photosynthesis, forests renew the oxygen supply in the atmosphere by absorbing atmospheric CO2 and moderating the greenhouse effect. Forests provide an environment for many species of plants and animals, thus protecting and sustaining the diversity of nature. Forests clean the environment by muffling noises, buffering strong winds, and stopping dust and gases. They help regulate surface water runoff, moderately high and low temperatures, and prevent soil erosion. 37 CU IDOL SELF LEARNING MATERIAL (SLM)
In performing these functions, forests stabilize the climate and shape the landscape. Forests are also popular areas for relaxation and recreation. Decomposed leaves from humus which is the biggest source of soil fertility. Forests keep the environment pleasant because they get moisture from the earth through their roots and spread it in the air through their leaves. Deforestation Deforestation is the process of removal of (or) elimination of forest resources due to many natural or man-made activities. It is the destruction of forests. Causes of Deforestation The primary and most common reasons for deforestation are known as the direct causes. Logging, overpopulation, urbanization, dam construction is under direct causes. The other main cause of deforestation is the natural cause as it is caused naturally by Mother Nature. Direct Causes of Deforestation Overpopulation, Urbanization, and Settlement Construction and Development projects Growing food needs Shifting cultivation Commercial logging Fuel requirements Raw materials for industrial use Overgrazing Mining operations and oil exploration Natural Causes of Deforestation Forest fires Acid rain Volcanic eruptions Typhoon Consequences and Effects of Deforestation Soil Erosion Disruption of the water cycle Loss of biodiversity Loss of forest products 38 CU IDOL SELF LEARNING MATERIAL (SLM)
Flooding and drought Climate change Desertification Silting of watercourses, lakes, and dams Control of Deforestation The use of wood for fuel should be discouraged. Instead, biogas and solar energy should be used for domestic, commercial and industrial purposes. It should be made compulsory that a new plant should be planted for every tree cut. Agro-forestry programmes should be implemented. It includes the planting of trees for forestry, farming, and animal husbandry on the same land. Afforestation programmes should also be implemented in areas of intense Deforestation. Developing comprehensive anti-desertification programs and integrating them into national development plans and national environmental planning. Emphasizing laws and regulations. Strict implementation of the law of Forest Conservation Act. Problem We are all personally responsible for releasing carbon dioxide into the atmosphere by burning fossil fuels for transportation (driving and flying) and home energy (electricity, heating, and cooling). This leads to global warming, which is destroying Earth's biodiversity and native ecosystems. Solution Reduce your use of fossil fuels Protect native forests as \"carbon storehouses\" Help plant native trees in urban and deforested areas Benefits of Planting Native Trees They help stop global warming by reducing greenhouse gases. They reduce soil erosion and water pollution. They provide habitat for native wildlife. They improve human health by producing oxygen and improving air quality. They reduce home energy needs by providing shade in summer and a windbreak in winter. Facts about the benefits provided by planting one tree: Absorbs over a ton of harmful greenhouse gases over its lifetime. 39 CU IDOL SELF LEARNING MATERIAL (SLM)
Produces enough oxygen for four people every day. Provides the equivalent cooling effect of ten room-size air conditioners operating 20 hours a day. Provides an estimated 273$ worth of environmental benefits every year of its life. 2.4 WATER RESOURCES About three-fourth of the earth’s surface is occupied by oceans which contain about 97.5 % of the earth’s water in strongly saline condition. The rest 2.5% is fresh water, and all of this is not available for direct human use. Most of the fresh water is frozen as polar or glacial ice (1.97%). Remaining fresh water occurs as ground water (0.5%) and water in lakes and rivers (0.02%), soil (0.01%) and atmosphere (0.0001%). Thus, only a small fraction of fresh water is available for human consumption. More so the distribution of fresh water is geographically uneven varying greatly from country to country and even within a country from one region to another. About 84% of the total global evaporation occurs from ocean surface and 16% from land surface. At any given time, the amount of moisture in the air is only enough to meet a total rainfall requirement of 10 days. Thus, there is very fast movement of water from ocean and land into the atmosphere and an average residence time of water in the air is only about 10 days. About 77% of the total rainfall on earth is received on the sea surface (as against 84% evaporation from this segment) and 23% on land (16% share of total evaporation to the atmosphere). There is a net gain of 7% rainfall water on land and this excess is returned to the oceans by surface runoff through rivers and sub-surface water flows. On global basis, the hydrological cycle is perfectly balanced as the total annual evaporation matches with annual precipitation. Uses of Water Commercial water use includes fresh water for motels, hotels, restaurants, office buildings and other commercial facilities, civilian and military institutions. Domestic water use Includes water that is used in the home every day, including water for normal household activities such as drinking, food preparation, bathing, washing clothes and dishes, flushing toilets and watering lawns and gardens. Industrial water usesfor industrial purposes such as processing, cleaning, transportation, dilution and cooling in manufacturing facilities. Irrigational water use is water artificially applied to farms, orchards, pastures and horticultural crops, as well as water used to irrigate pastures, for frost and freeze protection, chemical application, crop cooling, harvesting and for the leaching of salts from the crop root zone. 40 CU IDOL SELF LEARNING MATERIAL (SLM)
Livestock water use includes water for stock animals, feed lots, dairies, fish farms and other nonfarm needs. Mining water use includes water for the extraction of naturally occurring minerals, solids such as coal and ores; liquids such as crude petroleum; and gases such as natural gas. The category includes quarrying, milling (such as crushing, screening, washing and floatation), and other operations as part of mining activity. Public supply water use refers to water withdrawn by public and private water suppliers, such as county and municipal water works, and delivered to users for domestic, commercial and industrial purposes. Thermoelectric power water use is the amount of water used in the production of electric power generated with heat. Recreational water use is usually a very small but a growing percentage of total water use. Recreational water use is mostly tied to reservoirs and includes water used for recreational purposes such as boating, swimming, fishing and theme parks. Environmental water use includes artificial wetlands, artificial lakes intended to create wildlife habitat, fish ladders around dams and water releases from reservoirs timed to help fish spawn. Problems Related to Water Use About 40% of the world’s population lives in arid or semi-arid regions. These people spend substantial amounts of time, energy and effort in obtaining water for their domestic and agricultural use. To meet the needs of the huge population, surface waters (ponds, lakes, rivers etc.) are overdrawn. Due to over use of surface water the nearby wetlands may dry up. When more groundwater is removed for human use than can be recharged by rainfall or snow-melt, the ground water may also dry out. Excessive irrigation in semi-arid and arid regions can cause salt accumulation in the soil due to which crop productivity may decline. The continuous depletion of ground water along the coastal regions, often leads to the movement of saline sea water into freshwater wells spoiling their water quality. Estuaries become more saline and consequently less productive when surface waters are overdrawn. Heavy rainfall results in rapid runoff from areas having the exposed soil particularly on mountain slopes. This not only causes soil erosion but puts lowland areas at extreme risk of destruction due to flooding. Uncontrolled soil erosion results in sedimentation of waterways that can harm fisheries. Conservation and Management of Water Resources The main approaches for conservation of water are: Reducing agricultural water wastage by increasing efficiency of irrigation. By the traditional method of irrigation plants absorb less than 50% of the water applied to the soil, the rest is lost. Reducing water wastage in industry by recycling the used water. 41 CU IDOL SELF LEARNING MATERIAL (SLM)
Reducing domestic water wastage by constructing waste water treatment plants and recycling the treated water. Rain water harvesting by employing practices to store rain water and recharge ground water. Afforestation and protection of watersheds to improve water economy. Some important water management approaches to provide a sustainable supply of high- quality water are: Construction of dams and reservoirs to ensure year-round supply of water and, in addition, controlling flood and generating electricity. Desalinization of seawater and saline ground water, making it fit for drinking and other purposes. Diversion of water bodies (e.g., through canal) to increase the natural supply of water to a particular area. Regular dredging and desiltation of water bodies. 2.5 MINERAL RESOURCES Minerals essential to our industrialized society and daily life are non-renewable resources. Due to the increase in industrialization, the consumption of minerals has increased tremendously all over the world. The minerals now in short supply (e.g., silver, copper, mercury, tungsten, etc.) will probably be exhausted within next 20 to 100 years. Even the minerals which are relatively plentiful, e.g., iron and aluminum, will become extremely expensive because of the depletion of large, rich and easily accessible deposits of these metals. Minerals can be metallic, e.g., iron, copper, gold, etc. or non-metallic, e.g., sand, stone, salt, phosphates, etc. Some important minerals and their uses are given in Table 2.2. The minerals occur naturally in the earth’s crust; however, their distribution is not even. Minerals Uses Metal elements Aluminium Structural material, packaging Chromium Chrome plating, steel alloys Alloy material in gold jewellery, silverware, brass and bronze; Copper electric wiring, pipes, cooking vessels Jewellery, dentistry, alloys Gold Primary component of steel Iron Pipes, batteries, electrodes, pigments Lead Alloy steels, disinfectants Manganese Coins, alloys, metal plating Nickel 42 CU IDOL SELF LEARNING MATERIAL (SLM)
Platinum Jewellery, equipment’s, industrial catalyst Potassium Fertilizer, glass, photography Silver Jewellery, vessels, photography, alloys Uranium Fuel in nuclear power plants, tinting glass Tin Cans, containers, alloys Zinc Brass, electrodes, medicine Non-metal elements Phosphorous Medicine, fertilizers, detergents Sulphur Insecticides, rubbers, medicine Liquid metal element Mercury Thermometers, dental inlays, electric switches Table 2.1 Important Minerals and their Uses Effects and Consequences of Mining Extraction of minerals (i.e., mining), processing and disposal of minerals have negative effects on environment. Mining not only disturbs and damages the land but also pollutes the soil, water and air. The land that has been destroyed due to mining is known as derelict land or my spoil. Such derelict lands can be reclaimed or restored to a semi natural condition by re- vegetation to prevent further degradation and also to make the land productive for other purposes. Environmental Damage Caused by Mining Activities De-vegetation and defacing of landscapes Removal of natural ecosystem and creation of trenches and open pits Subsidence of land Soil erosion and reduction in soil fertility Groundwater contamination Surface water pollution Air pollution Occupational health hazards (asbestosis, silicosis, black lung disease etc.) Major Mines in India Causing Severe Problems Jaduguda Uranium Mine, Jharkhand – Exposing local people to radioactive hazards Jharia Coal Mine, Jharkhand – Underground fires leading to land subsidence and forced displacement of people Sukinda Chromite Mines, Odisha – Seeping of hexavalent chromium into river posing serious health hazards, Cr6+ being highly toxic and carcinogenic 43 CU IDOL SELF LEARNING MATERIAL (SLM)
Kudremukh Iron Ore Mine, Karnataka – Causing river pollution and threat to biodiversity East Coast Bauxite Mine, Odisha – Land encroachment and issue of rehabilitation unsettled North Eastern Coal Fields, Assam – Very high sulphur contamination of groundwater Conservation of Minerals Mineral conservation measures involve their recycling and reuse. In recycling, used and discarded items are collected, remelted and reprocessed into new products, e.g., iron scraps, aluminum cans, etc. Some minerals present in products can be recycled, e.g., gold, lead, nickel, steel, copper, aluminum, silver, zinc, etc., Minerals in other products are lost through normal use such as paints containing lead, zinc or chromium. During reuse, used products are collected and used over and over again, e.g., reuse of glass bottles. The benefits of reuse are greater than those of recycling. All products, however, may not be reused. Recycling and reusing not only renew the mineral resources but also help in: 1. Saving unspoiled land from the disruption of mining, 2. Reducing the amount of solid waste that must be disposed, and 3. Reducing energy consumption and pollution. The substitution of more abundant minerals for scarce minerals may prove useful provided environmental implications are kept in mind. In recent years, plastics, ceramics, high strength glass fibers and alloys have been substituted for scarcer materials like steel, tin and copper in many industries. Although substitution can extend our mineral supplies, it is not a solution of the problem. To maintain the extended supply of minerals for a longer time, consumers must decrease their mineral consumption by becoming a low waste society. Products that are durable and repairable should be encouraged to be used again instead of discarding them as waste. Manufacturing industries may also use the waste products of one manufacturing process as the raw materials for another industry. 2.6 LAND RESOURCES Earth’s one-fourth area is formed by land which is largely covered with natural forests, grasslands, wetlands, and man-made urban and rural settlements along with agriculture. Low lying areas covered with shallow water are called wetlands. The wetlands are transitional 44 CU IDOL SELF LEARNING MATERIAL (SLM)
between terrestrial and aquatic areas. Soil is the upper weathered crust of earth which supports plant growth. In all land resources soil is of critical importance. Estimates indicate that over 50% of land area in India suffers from soil degradation. The yield of all biotic products in terrestrial ecosystems depends on soil fertility. Soil is composed of inorganic particles, organic matter, air, water and a variety of organisms. It takes decades or even centuries for the development of soil horizons having different physiochemical properties. Human activities often create worldwide problems like soil erosion and depletion of fertility. Land Degradation The process of deterioration of soil or loss of fertility is known as land degradation or soil degradation. Causes of Land Degradation More land is needed for producing food, fiber and fuel wood. So, land is degraded due to over exploitation. Urbanization reduces the extent of agricultural lands. Urbanization leads to deforestation, which in turn affects millions of plants and animals. Fertilizers and pesticides affect the fertility of the soil and causes land pollution. Increase in food production generally leads to damage of top soil through nutrient depletion. Water logging, soil erosion, salination and contamination of the soil with industrial wastes can cause land degradation. Effects of Land Degradation Soil texture and soil structure are disturbed. Loss of soil fertility. Loss of valuable nutrients. Increase in water logging, salinity, alkalinity and acidity problem. Loss of economy, agriculture and biodiversity. Desertification It is a form of land degradation. It is a progressive destruction or degradation of arid or semi-arid lands. Causes of Desertification Deforestation Over grazing Over utilization of water 45 CU IDOL SELF LEARNING MATERIAL (SLM)
Mining and quarrying Climate change Excessive use of fertilizers and pesticides Soil Erosion The process of removal of superficial layer of the soil from one place to another is called soil erosion. Types of Soil Erosion Normal erosion: It is caused by gradual removal of top soil by the natural process. The rate of erosion is less. Accelerated erosion: It is caused by manmade activities. The erosion is much faster than the rate formation of soil. Causes of Soil Erosion Water causes soil erosion in the form of rain, run off, rapid flow and wave action. Wind is an important climatic agent, which carry away the fine particles of soil create soil erosion. Over grazing, mining and deforestation are the major biotic agent cause soil erosion. 35% of soil erosion is due to over grazing and 30% is due to deforestation. Landslides can cause soil erosion. Construction of dams, buildings, roads remove protective vegetal cover and leads to soil erosion. Effects of Soil Erosion Soil fertility decreases due to the loss of top soil layer. The soil loses its ability to hold water and sediments. Sediments run off can pollute water and affect aquatic life. Soil Conservation Practices The art of soil conservation is based on following basic principles To reduce the concentration of water flowing on the land surface or slope. To reduce the velocity of water flowing on the land surface or slope. To increase the rate of infiltration of water into the natural soil. To increase the grain size of soil particles. To reduce the wind velocity near the ground by growing vegetation. To protect and conserve the natural drainage pattern of the land Control of Soil Erosion 46 CU IDOL SELF LEARNING MATERIAL (SLM)
Conservational Tillage: The process of mixing the residues from previous crops into the soil by ploughing is called conservational tillage. It improves soil permeability and increase organic matter, which in turn improve soil moisture and nutrients. Organic Farming: Process of increasing organic input to the soil. e.g., Bio fertilizers Crop Rotation: Process of growing different crops in successive year on the same land. It prevents the loss of fertility of the soil. Contour Ploughing: It is very useful areas with low rain fall, i.e., placing some furrows to store water, which reduces runoff and erosion. Mulching: Soil is covered with crop residues and other form of plant litters. Strip Cropping: Planting of crops in rows to check flow of water. Terrace Farming: Conversion of steep slopes in to a series of broad terraces which run across the contour. It reduces soil erosion by controlling run off. Agro-Forestry: Planting crops in between rows of trees or shrubs, that can provide fruits and fuel wood. After harvesting the crops, the soil will not be eroded because trees and shrubs will remain on the soil and hold the soil particles. Wind Breaks: Trees are planted in long rows along the boundary of cultivated lands, which block the wind and reduce soil erosion. 2.6.1 Land Resources – Availability and Quality Global land cover classification schemes have been devised that allow quantification of each 5’ by 5’ latitude/longitude grid-cell into shares of seven main land-use/land-cover categories. The estimation of shares seeks to formally and consistently integrate up-to-date geographical data sets, obtained from remote sensing and other sources, into statistical information compiled by FAO and/or national statistics bureaus. The global land mass, excluding Antarctica, comprises 13.3 billion ha. About 11 percent (1.6 billion ha) is currently used to cultivate agricultural crops; 28 percent is under forest; 35 percent comprises grassland/woodland ecosystems; 22 percent is barren or sparsely vegetated, and 3 percent each is used for human settlement or infrastructure and occupied by inland water. The intensity of each land-cover type varies substantially across the globe according to climatic conditions and anthropogenic influences. For example, while cultivated land is less than 10 percent in most African regions, it accounts for more than one- third of the land in the countries of Southern Asia. The highest share of cultivated land in total land, about one-third, is found for Southern and Western Europe, the Caribbean and Southern Asia. Cultivated land area, in terms of per capita use in 2000, were highest in Australia (more than 2.2 ha per person), in Northern America and the region of Eastern Europe and Russia (in both regions about 0.7 ha per person). 47 CU IDOL SELF LEARNING MATERIAL (SLM)
Use of cultivated land per capita in the more developed countries was on average 0.5 ha in 2000 – ranging from 0.2 ha in Western Europe to 0.7 ha in Northern America and more than 2.2 ha in Australia. This figure will change little owing to population dynamics until 2050. In contrast, current cultivated land used per capita is only 0.2 ha in less developed countries, a value which would further decrease to 0.1 ha in 2050 in the absence of further cultivated land expansion. It has been suggested that the minimum arable land required to sustainably support one person is 0.07 ha (Myers, 1998). This is a threshold used by United Nations organizations to evaluate the land’s carrying capacity. Arable land is less than 0.1 ha per person so it would be difficult to maintain a minimal nutrition level (Uitto and Ono, 1996). 2.7 ENERGY RESOURCES Energy is defined as the ability to do work. Future energy needs of rapidly expanding human population will demand the exploitation of most energy sources. Broadly, energy resources can be recognized as non-renewable or renewable. Non-renewable energy sources include various fossil fuels and nuclear energy. Fossil fuels include petroleum products, natural gas and coal. Nuclear energy is mainly obtained from the nuclear fission of the uranium. The world reserves of fossil fuels and uranium are limited and will eventually be depleted. Burning fossil fuels for energy has negative environmental consequences such as global warming, air pollution, acid rain and oil spills. It has become necessary to minimize use of nonrenewable energy resources, and to replace them with renewable resources. Renewable energy resources are regenerated by natural processes so that they can be used indefinitely. Renewable energy generally causes much less negative environmental impact than fossil fuels or nuclear energy. With the current state of technology, the generation of renewable energy is often more expensive than energy produced by fossil fuels or nuclear energy, however, with technological advances the costs of renewable energy is expected to decrease. Among the renewable energy sources, the most important one is solar energy. The other renewable energy resources are hydropower, wind, geothermal energy, ocean waves and tidal energy. 2.7.1 Hydroelectric Energy Hydropower Water falling from a height turns turbines at the bottom of dams to generate electricity. Hydropower produces approximately one-fourth of the world’s electricity and is usually 48 CU IDOL SELF LEARNING MATERIAL (SLM)
cheaper than electricity produced by thermal power plants. However, building a dam to hold the water leads to several environmental problems; e.g., submergence of plant and animal habitats and displacement of people. Hydro energy is simply energy that is taken from water and converted to electricity. Hydro energy can be obtained by using many methods of capture. The most common method of using energy from water is a hydroelectric dam, where water coming down through an area causes turbines to rotate and the energy is captured to run a generator. Power can also be generated from the energy of tidal forces or wave power, which uses the energy created by waves. Ocean and Wave Energy The ocean provides several forms of renewable energy, and each one is driven by different forces. Energy from ocean waves and tides can be harnessed to generate electricity, and ocean thermal energy from the heat stored in sea water can also be converted to electricity. Using current technologies, most ocean energy is not cost-effective compared to other renewable energy sources, but the ocean remains and important potential energy source for the future. Tidal and Wave Energy Gravitational pull exerted by sun and moon causes tides to develop. As the sea level rises, water may be diverted through suitable channel to inshore reservoirs, driving the turbines during its entry Air currents rubbing the ocean surface produce waves which are pushed to the shores where its energy is dissipated as waves break when they strike the shoreline Floating propellers placed along the shores may be kept in continuous motion by these waves. Their kinetic energy may be used to drive turbines. 2.7.2 Nuclear Energy Nuclear energy is the energy in the nucleus, or core, of an atom. Atoms are tiny units that make up all matter in the universe, and energy is what holds the nucleus together. There is a huge amount of energy in an atom's dense nucleus. In fact, the power that holds the nucleus together is officially called the \"strong force.\" Nuclear energy can be used to create electricity, but it must first be released from the atom. In the process of nuclear fission, atoms are split to release that energy. Nuclear reactors use fission, or the splitting of atoms, to produce energy. Nuclear energy can also be produced through fusion, or joining (fusing) atoms together. The sun, for 49 CU IDOL SELF LEARNING MATERIAL (SLM)
instance, is constantly undergoing nuclear fusion as hydrogen atoms fuse to form helium. Because all life on our planet depends on the sun, you could say that nuclear fusion makes life on Earth possible. Nuclear Reactor (or) Nuclear Power Plant A nuclear reactor, or power plant, is a series of machines that can control nuclear fission to produce electricity. The fuel that nuclear reactors use to produce nuclear fission is pellets of the element uranium. In a nuclear reactor, atoms of uranium are forced to break apart. As they split, the atoms release tiny particles called fission products. Fission products cause other uranium atoms to split, starting a chain reaction. The energy released from this chain reaction creates heat. The heat created by nuclear fission warms the reactor's cooling agent. A cooling agent is usually water, but some nuclear reactors use liquid metal or molten salt. The cooling agent, heated by nuclear fission, produces steam. The steam turns turbines, or wheels turned by a flowing current. The turbines drive generators, or engines that create electricity. Rods of material called nuclear poison can adjust how much electricity is produced. Nuclear poisons are materials, such as a type of the element xenon, that absorb some of the fission products created by nuclear fission. The more rods of nuclear poison that are present during the chain reaction, the slower and more controlled the reaction will be. Removing the rods will allow a stronger chain reaction and create more electricity. Impacts of Nuclear Reactors Radioactive waste is what is left over from the operation of a nuclear reactor. Radioactive waste is mostly protective clothing worn by workers, tools, and any other material that have been in contact with radioactive dust. Radioactive waste is long-lasting. Materials like clothes and tools can stay radioactive for thousands of years. Used fuel and rods of nuclear poison are extremely radioactive. The used uranium pellets must be stored in special containers that look like large swimming pools. Water cools the fuel and insulates the outside from contact with the radioactivity. Some nuclear plants store their used fuel in dry storage tanks above ground. The government regulates how these materials are disposed of so they don't contaminate anything else. 50 CU IDOL SELF LEARNING MATERIAL (SLM)
Search
Read the Text Version
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
- 68
- 69
- 70
- 71
- 72
- 73
- 74
- 75
- 76
- 77
- 78
- 79
- 80
- 81
- 82
- 83
- 84
- 85
- 86
- 87
- 88
- 89
- 90
- 91
- 92
- 93
- 94
- 95
- 96
- 97
- 98
- 99
- 100
- 101
- 102
- 103
- 104
- 105
- 106
- 107
- 108
- 109
- 110
- 111
- 112
- 113
- 114
- 115
- 116
- 117
- 118
- 119
- 120
- 121
- 122
- 123
- 124
- 125
- 126
- 127
- 128
- 129
- 130
- 131
- 132
- 133
- 134
- 135
- 136
- 137
- 138
- 139
- 140
- 141
- 142
- 143
- 144
- 145
- 146
- 147
- 148
- 149
- 150
- 151
- 152
- 153
- 154
- 155
- 156
- 157
- 158
- 159
- 160
- 161
- 162
- 163
- 164
- 165
- 166
- 167
- 168
- 169
- 170
- 171
- 172
- 173
- 174
- 175
- 176
- 177
- 178
- 179
- 180
- 181
- 182
- 183
- 184
- 185
- 186
- 187
- 188
- 189
- 190
- 191
- 192
- 193
- 194
- 195
- 196
- 197
- 198
- 199
- 200
- 201
- 202
- 203
- 204
- 205
- 206
- 207
- 208
- 209
- 210
- 211
- 212
- 213
- 214
- 215
- 216
- 217
- 218
- 219
- 220
- 221
- 222
- 223
- 224
- 225
- 226
- 227
- 228
- 229
- 230
- 231
- 232
- 233
- 234
- 235
- 236
- 237
- 238
- 239
- 240
- 241
- 242
- 243
- 244
- 245
- 246
- 247
- 248
- 249
- 250
- 251
- 252
- 253
- 254
- 255
- 256
- 257
- 258
- 259
- 260
- 261
- 262
- 263
- 264
- 265
- 266
- 267
- 268
- 269
- 270
- 271
- 272
- 273
- 274
- 275
- 276
- 277
- 278
- 279
- 280
- 281
- 282
