Environmental Science and Engineering ENVIRONMENT, ECOSYSTEM AND BIODIVERSITY DEFINITION, SCOPE AND IMPORTANCE Environmental science is the study of nature and the facts about environment. Basically environment can be defined as “all the social, economical, physical & chemical factors that surrounds man” (or) “all abiotic and biotic components around man-all living and non living things surrounds man”. Environment Components can be divided into biotic and abiotic components. According to ancient man the environment was the Panchaboodhas (i.e) air, water, land, sky and energy. The human were disciples of nature. They were able to protect themselves from harmful one and protect the others. But according to modern man the env. is only air land and water. Exploitation of various earth resources to satisfy the increasing needs of human population has resulted in 1) depletion of various resources of earth 2) pollution. Principles of environmental education:
Examine the major environmental issues
discover the root cause
develop problem solving skills
promote co-operation in solving problems
emphasis active participation in prevention and solution to problems.
Scope of environmental science:
Studying the interrelationship between the components of env.
Carrying out impact analysis and env. Audit
Preventing pollution from existing and new industries
Stopping the use of biological and nuclear weapons
Managing unpredictable disasters etc.
Public awareness: Environmental Pollution or problems cannot be solved by mere laws. Public participation is an important aspect which serves the environmental Protection.
Public awareness of environmental Is at infant stage
30-40% of public of developing country are aware of environmental. Problems but they do not bother about it.
Ignorance and incomplete knowledge has lead to misconceptions
Environmental Science and Engineering
Development and improvement in std. of living has lead to serious environmental disasters
Debate on environmental Issues are treated as anti-developmental
Reasons for environmental Ignorance:
science, technology and economics failed to integrate the knowledge on environmental Aspects in curriculum
the decision makers do not process environmental Angle of decision making
consideration of economic growth, poverty eradication has lead to environmental Degradation
only few developmental activities are made considering the environmental Aspects.
Need For Public Awareness: The United Nations Conference on Environment and Development held at Reo de Janeiro in 1992 (popularly known as „Earth Summit‟) and world summit on sustainable development at Johannesburg in 2002, have highlighted the key issues of global environmental concern. They have attracted the attention of people. Any government at its own cannot achieve the goals of clear environment until the public participate in action. Public participation is possible only when the public is aware about the ecological and environmental issues. Eg. Ban- the littering of polythene. Methods to propagate environmental Awareness: 1. Among students through education – introducing environmental studies in the curriculum. 2. Among public through mass media- environmental programmmes through TV, radio etc. 3. Among decision makers, planners, leaders etc. Role of NGOs 1. Advise the government in interacting with ground level people 2. Organize public meetings to create environmental awareness Eg. Recent report of „centre for science and environment‟ on permissible limits of pesticides in cola drinks. Public awareness is needed in the area 1. study of natural resources-conservation and management 2. ecology and biodiversity – conservation 3. environmental Pollution and prevention
Environmental Science and Engineering 4. social issues related to development and environment 5. human population and environment. Concept Of Ecosystem: Living organisms cannot be isolated from their non-living environment because the later provides materials and energy for the survival of the farmer. An ecosystem is therefore defined as a natural functional ecological unit comprising of living organisms and their non-living environment that interact to form a stable self supporting system . Eg. Pond, lake, desert, grassland, forest, etc. Ecosystems Ecology – earnest Haeckal- 1869 –derived from „oikos‟ – home , logy – study -deals with the study of organisms in their natural home interacting with their surroundings. Ecosystem – Tansley (1935) – self regulating group of biotic communities of species interacting with one another and with their non-living environment exchanging energy and matter Ecosystem characteristics Structural features – composition and organization of biological communities and abiotic components constitute – Structure of Ecosystem Biotic structure – Plants , animals , microorganisms – form biotic components – nutritional behavior and status in the ecosystem – producers or consumers – how do they get their food. Structure of Ecosystem 1. Abiotic or non-living components or physical components 2. Biotic or Living components 3. Energy components. Abiotic Components: Abiotic components enter the body of living directly or indirectly take part in metabolic activities and return to environment. Abiotic components are as follows 1. Atmosphere –The cover of air that envelopes the earth is known as atmosphere. Compostion – Nitrogen-78%, oxygen- 2%, other gases- 1% 2. Lithosphere or Interior of Earth – Solid Earth –Radius 6371- density -5.5 3. Hydrosphere – 97% earth‟s water is in oceans – Fresh water – 3%.
Environmental Science and Engineering Structure of Atmosphere: Five Layers 1. 2. 3. 4. 5.
Troposphere –lower portion – extends from 0-18 kms, temperatureStratosphere -18- 50 kms- Temperature (-2ºC to -56ºC )- Ozone layer Mesosphere- extends from 50-85 kms- Temperature drops to (-95ºC) Ionosphere or Thermosphere –extends up to 500 kms. Temperature – raises up to 1200ºC Exosphere – extends up to 1600 km- temperature very high due to solar radiation.
Functions of Atmosphere: It maintains heat balance on the earth by absorbing IR radiation. Oxygen – support life on living organism. Co2 - essential for photosynthetic activity of plants. N2 - essential nutrient for plant growth. Interior of Earth or Lithosphere: Three major Zones 1. Crust – top most layer- solid thickness 30 – 40 Km in continents and 5 – 6 km in oceans. Rocks of the earth crust – 3 types – Igneous , Sedimentary, Metamorphic. 2. Mantle – average density 3.3 – Thickness – 2860 – density increases with depth. 3. Core – (outer core – solid , inner core – liquid). depth – 2900 km from the surface of the earth – density -12 – not exact composition. Functions of Lithosphere: 1. It is home for human beings and wild life. 2. It is store house of minerals and organic matter. Functions of Ecosystems Ecosystem characteristics Structural features – composition and organization components constitute – Structure of Ecosystem
of biological communities and abiotic
Biotic structure – Plants , animals , microorganisms – form biotic components – nutritional behavior and status in the ecosystem – producers or consumers – how do they get their food. Producers – Photosynthesis – photoautotroph (auto – self, photo- light) Chemotrops or Chemosynthetic organisms – Chemicals Consumers – feeding upon other organisms
Environmental Science and Engineering Types – Herbivores – Plant eating animals – primary consumers Eg ; rabbit Carnivores – Feed on consumers – Secondary Consumers - feed on other carnivores – Tertiary / Consumers. Omnivores – feed on both plants and animals – eg. Humans, rat, fox. Detritivores - (Detritus feeder or Saprotrophs ) – feed on dead on organisms or decomposed matter eg; beetles, termites,ants , crabs, earthworms. Decomposers – nutrition breaking down in to complex organic molecules to simpler organic organic compounds – bacteria and fungi. Abiotic Structure. – physical and chemical components of an ecosystem. Physical factors – sunlight , temperature ,annual rainfall, soil type, water availability, water currents etc. –strong influence on the ecosystem. Chemical factors; major essential nutrients – C, N, P, H, O, S. Biotic Components – Abiotic components and viceversa – linked through – energy flow, matter cyling. Functional Attributes. 1. 2. 3. 4. 5.
Food chain, Food web and trophic structure. Energy flow Cycling of Nutrients (Biogeochemical cycles) Primary and secondary production Ecosystem development programme
Food Chains -
Sequence of eating and being eaten in an ecosystem.
Grass
Grasshopper
Frog
snake
Hawk
(Grassland Ecosystem) Grazing food chains – Starts with green plants. Grass
Rabbit
Phytoplanktons
Fox Zooplanktons
Small fish
Carnivores (fish)
Environmental Science and Engineering Food Web -
Network of food Chains
ENERGY FLOW IN ECOSYSTEM: Energy is defined as the capacity to do work. For living organisms, it is the basic force responsible for running all the metabolic activities. The flow of energy from producer level to top consumer level is called energy flow. The flow of energy in an ecosystem is unidirectional. It flows from producer level to consumer level and never in the reverse direction. The process of energy flow involves transfer of energy from autotrophs to various components of heterotrophs and help in maintaining bio diversity. The main source of energy in the ecosystem is sunlight. About 80% of energy is lost during flow of energy from one trophic level to the next one. Sun
Producer
Herbivores
Carnivores
Top carnivores
Decomposers
ECOLOGICAL SUCCESSION FOOD CHAIN Plants by photosynthesis convert solar energy into protoplasm. Small herbivores consume the vegetable matter and convert into animal matter which in turn eaten by large carnivores. This sequence of eaten and being eaten , produces transfer of food energy known as food chain. Producers
Consumer I order
(Plants)
(Deer)
Consumer II order (Tiger, Lion)
Decomposers (Bacteria, fungi)
FOOD WEB: The food relationship between various organisms is being depicted by linking all the possible prey and predators of different food level. In an ecosystem linking of feeding habit relations will provide a food web.
Mouse Grass
snake
Rabbit Grasshopper
Hawk Lizard
Environmental Science and Engineering ECOLOGICAL PYRAMIDS: The energy biomass and number of organisms gradually decreases from the producer level to the consumer level. The total mass of herbivores in an ecosystem will generally be less than the total mass of plants. Similarly the total mass of carnivores will be less than the total mass of herbivores. The graphical representation of the number, biomass and energy of various energy levels is called ecological pyramid. In any ecological pyramid the producer forms the base and the successive levels form the tires which can make the apex. Types of ecological pyramids: a) pyramid of numbers b) pyramid of biomass c) pyramid of energy Eg. Grassland ecosystem – pyramid of number – upright pyramid
birds
insects
Worms
grass
Parasite ecosystem – pyramid of number – inverted pyramid
Bacteria, fungi
Parasites
Birds
Tree
Environmental Science and Engineering MAJOR TYPES OF ECOSYSTEMS a. FOREST ECOSYSTEM Definition: It is a natural ecosystem consisting of dense growth of trees and wild animals Types: tropical – deciduous, evergreen, wet green Littoral and swamps Sub tropical Characteristics: Abiotic: soil, sun light, temperature etc Biotic : forest trees, shrubs and animals Structure: Producer
:
trees and shrubs
Consumer
:
Primary – elephants, deer etc. Secondary – snakes, birds, lizards etc Tertiary – lions, tigers etc
Decomposers :
fungi, bacteria
Functional components: Ecological pyramids (upright)
lions
lizards
deers
trees
Environmental Science and Engineering GRASSLAND ECOSYSTEM: dominated by grass – few shrubs and trees are also found – rainfall average but erratic – overgrazing leads to desertification. Three types – depending on the climate 1. Tropical grass lands – found near the boarders of tropical rain forests. Eg. Savannas in Africa. Animals – Zebra, giraffes etc. – fires are common in dry seasons – termite mounds produce methane – leads to fire – high in photosynthesis – deliberate burning leads to release of high CO2 – global warming. 2. Temperate grasslands – flat and gentle slopes of hills. Very cold winter and very hot summer - dry summer fires do not allow shrubs and trees to grow – soil is quite fertile – cleaned for agriculture. 3. Polar grasslands – found in arctic polar region – organism – arctic wolf, fox, etc. – A thick layer of ice remains frozen under the soil surface throughout the year – known as permafrost – summer insects and birds appear. Components: Structural Components: Abiotic: soil pH, nutrients, soil moisture, temp, climatic conditions, etc. Biotic: grass, caterpillar, butterfly, worms, insects, birds, etc. Functional components: Ecological pyramid birds
insects
Worms
grass
Environmental Science and Engineering Energy flow:
Grass
worms
Insects
small birds huge birds
Decomposition
sediments c. DESERT ECOSYSTEM Types: 1. tropical desert-found in Africa-Sahara and Rajasthan –Thar 2. temperate desert-south California-Majave 3. cold desert-China-Gobi desert Characteristics: 1. Air is dry 2. Climate is hot 3. Annual rainfall is less than 25 cm 4. Vegetation is poor d.AQUATIC ECOSYSTEM Definition: Deals with water bodies and biotic communities present in them-Classified as fresh water and marine ecosystems. Fresh water systems are classified as lentic and lotic ecosystems. Types: 1. Pond ecosystem: Small fresh water ecosystem – seasonal in nature – organisms: algae, aquatic plants, insects, fishes etc. Ponds are very often exposed to anthropogenic pressure like cloth washing, bathing, cattle bathing, swimming etc. 2. Lake ecosystem: Big fresh water ecosystem – Zonation or stratification, especially during summer is a common one.
Environmental Science and Engineering Top layer – shallow, warm, prone to anthropogenic activities – Littoral zone Second layer – enough sunlight, high primary productivity – Limnetic zone Third layer – very poor or no sunlight – Profundal zone Eg. Dal lake in Srinagar, Naini lake in Nainital Organisms: planktons – phytoplankton eg. Algae – zooplankton eg. Rotifers Nektons – that swims in water eg. Fishes Neustons – that float on the surface of water Benthos – that attached to sediments eg. Snails
Types of lakes : Many types- oligotrophic lakes – with less nutrient content – eutrophic lakes – with very high nutrient content due to fertilizer contamination – desert salt lakes – that contains high saline water due to over evaporation – volcanic lakes – formed by water emitted from magma due to volcanic eruptions – dystrophic lakes – that contains highly acidic water (low pH) – endemic lakes – lakes that contain many endemic species – etc. 3. Streams: fresh water ecosystem where water current plays a major role. Oxygen and nutrient content are uniform. Stream organisms have to face extreme difference in climatic conditions but they do not suffer from oxygen deficiency as pond and lake organisms. This is because large surface area of running water provides more oxygen supply. The animals have very narrow range of tolerance towards oxygen deficiency. Thus stream are worst victims of industrial pollution. River ecosystem: large streams flowing from mountain highlands are rivers. Three phases: 1. mountain highlands – rushing down water fall of water – large quantity of dissolved oxygen – plants attached to rocks and fishes that require more oxygen are found. 2. Second phase – gentle slopes of hills – warmer – supports the growth of plants and fishes that require less oxygen are seen. 3. Third phase: river shapes the land – lots of silts, nutrients are brought – deposited in plains and delta – very rich in biodiversity. 4. Oceans: Gigantic reservoirs of water covering >70% of earth surface – 2,50,000 species – huge variety of sea products, drugs etc. – provide Fe, Mg, oils, natural gas, sand etc. – major sinks of carbon di oxide – regulate biochemical cycles. Two zones: coastal zone – warm, nutrient rich, shallow – high sunlight – high primary productivity. Open sea – away from continental shelf – vertically divided in to 3 zones. 1. euphotic zone – abundant sunlight 2. bathyal zone – dim sunlight 3. abyssal zone – dark zone – world‟s largest ecological unit. Estuary: coastal area where river meet ocean – strongly affected by tidal actions – very rich in nutrients – very rich in biodiversity also – organisms are highly tolerant – many species are endemic – high food productivity – however to be protected from pollution.
Environmental Science and Engineering Characteristics: Structural Components: Abiotic: pH, nutrients, D.O, temp, climatic conditions, etc. Biotic: Phytoplankton, fishes, snails insects, birds, etc. Functional components: Ecological pyramid birds
fishes
Worms, insects
phytoplankton
Energy flow:
Phytoplankton
Insects
small fishes
huge fishes
Decomposition
sediments INTRODUCTION TO BIODIVERSITY Biodiversity is the abbreviated word for “biological diversity” (bio-life or living organisms, diversity-variety). Thus biodiversity is the total variety of life on our planet, the total number of races, varieties and species. The sum of total of various types of microbes, plants and animals (producers, consumers and decomposers) in a system.
Environmental Science and Engineering Biomes can be considered life zones, environment with similar climatic, topographic and soil conditions and roughly comparable biological communities (Eg. Grassland, forest). The biomes shelter an astounding variety of living organisms (from driest desert to dripping rain forest, from highest mountain to deepest ocean trenches, life occurs in a marvelous spectrum of size, shape, colour and inter relationship). The variety of living organisms, the biodiversity, makes the world beautiful. There are 1.4 million species known presently. But based on new discoveries, by research expeditions, mainly in tropics, taxonomists estimate there are between 3-50 million different species may be alive today. Insects make up more than one half of all known species and may comprise more than 90% of all species on earth. The concept of biodiversity may be analyzed in 3 different levels. They are 1 ecosystem diversity 2 species diversity 3 genetic diversity Ecosystem or ecological diversity means the richness and complexity of a biological community, including tropic levels, ecological processes (which capture energy), food webs and material recycling. Species diversity describes the number of kinds of organisms within individual communities or ecosystems. Genetic diversity is a measure of the variety of versions of same gene within individual species. Biodiversity Hotspots: Most of the world‟s biodiversity are near the equator especially tropical rain forest and coral reefs. Of all the world‟s species, only 10-15% live in North America and Europe. The Malaysian Peninsula, for instance, has at least 8000 species of flowing plants, while Britain, with an area twice as large, has only 1400 species. South America has 200 000 species of plants. Areas isolated by water, desert or mountain can also have high conc. of unique species and biodiversity. New Zealand, South Africa and California are all mid-latitude area isolated by barriers that prevent mixing up of biological communities from other region and produce rich, unusual collection of species. Significance of Biodiversity: Biosphere is a life supporting system to the human race. Each species in the biosphere has its own significance. It is the combination of different organisms that enables the biosphere to sustain human race. Biodiversity is vital for a healthy biosphere. Biodiversity is must for the stability and proper functioning of the biosphere.
Environmental Science and Engineering Besides these biodiversity is so important due to having consumptive use values, productive use values, social values, ethical values and aesthetic values. Benefits of biodiversity: We benefit from other organism in many ways. Even insignificant organisms can play irreplaceable roles in ecological systems or the source of genes or drugs that someday become indispensable. Food: Many wild plant species could make important contributions to human food suppliers either as they are or as a source of material to improve domestic crops. About 80,000 edible plants could be used by human. Drugs and medicine: Living organisms provides many useful drugs and medicines. The United Nations Development Programme derived from developing world plants, animals and microbes to be more than $30 billion per year. Eg. For natural medicinal products Penicillin – fungus is the source – Antibiotic Quinine – chincona bark - Malaria treatment Morphine – poppy bark – Analgesic Twenty years before, once the drugs were not introduced, childhood leukemia was fatal. Now the remission rate for childhood leukemia is 99%. Ecological benefits: Human life is inextricably linked to ecological services provided by other organisms. Soil formation, waste disposal, air and water purification, solar energy absorption, nutrient cycling and food production all depend on biodiversity. In many environments, high diversity may help biological communities to withstand environmental stress better and to recover more quickly than those with fewer species. Threats to biodiversity: Due to
Habitat loss Deforestation activities (cutting trees for timber, removal of medicinal plants) Production of hybrid seeds requires wild plants as raw material, farmers prefer hybrid reeds, many plant species become extinct Increase in the production of pharmaceutical companies made several number of medicinal plants and species on the verge of extinction. Removal of forest-cover for road laying and also due to soil erosion Illegal trade of wild life Population explosion, construction of dam, discharge of industrial effluents use of pesticides.
Environmental Science and Engineering
Poaching of wild life Due to poaching, illegal trade and smuggling activities most of our valuable fauna are under threat organised crime has moved into illegal wild life smuggling because of huge profit Eg. Tiger, Deer – for hides, Rhinoceros – for horns, Elephant – for ivory tusk, Sea Horse, Star turtle – sold to foreign market. (Extinction, the elimination of species, is a normal process of the natural world. Species die put and are replaced by others as part of evolutionary change. Human caused reduction: The climate change caused by our release of green house gases in the atm. could have catastrophic effects. Human disturbance of natural habitat is the largest single cause pf loss of biological diversity. Woodlands and grasslands are converted now use about 10% of the world‟s land surface for crop production and about twice the amount for pasture and grasslands.) Hunting: Over harvesting is responsible for depletion or extinction of many species. Eg. The American passenger pigeon was the world‟s most abundant bird. In spite of this vast population, market hunting and habitat destruction caused the entire population to crash with in 20 years.
Fragmentation; Habitat fragmentation reduces the biodiversity because many animals like bears and large cats require large territories to subsist. Some forest birds reproduce only in deep forest or habitat far from human settlement. A large island for example, can support more individuals of given species and therefore less likely to suffer extinction due to genetic problems and natural catastrophes.
Commercial products: Smuggling of fuels, hides, horns and folk medicines also affect the biodiversity in an abrupt manner. Conservation of biodiversity: In general biodiversity is generally disturbed by human activities. To solve the problems, it is essential to protect our bio diversity by two ways. 1. In-situ or on-site conversion 2. Ex-situ conservation In-situ conservation: Conservation of species in its natural habitat, in place where the species normally occurs The strategy involves establishing small or large protected areas, called protected areas Today in world, there are 9800 protected areas and 1500 national parks
Environmental Science and Engineering Methods: 1. Nature or biosphere reserves (Eg) Nilgiri Bio reserve 2. national parks and sanctuaries (Eg) Mudumalai, vedanthangal 3. on farm and home garden conservation for plants, vegetables and fruits to maintain traditional crop varieties. Ex- situ conservation: It involves maintenance and breeding of endangered plant and animal species under partially or wholly controlled conditions in zoos, gardens and laboratories The crucial issue for conservation is to identify those species which are more at risk of extinction. Methods: 1. 2. 3. 4. 5.
long term captive breeding shortage term propagation and release animal translocation and re introductions seed bank reproductive technology (i) embryo transfer technology (ii) cloning
Review questions: 1. Define Environmental science Environmental science is the study of the environment, its biotic and abiotic components and their interrelationships. 2. What are the important components of environment? Abiotic or non-living components Biotic or living component Energy component 3. What are the processes involved in hydrological cycle? Continuous evaporation, transpiration, precipitation of surface run off and ground water 4. Define biogeochemical cycle. Give example. The continuous circulation of all the essential elements and compounds required for life, from the environment to the organism and back to the environment.e.g., carbon cycle 5. What are the functions of lithosphere? It is a home for human beings and wild lives. It is a store house minerals and organic matters
Environmental Science and Engineering 6. Mention the various types of public participation. Pressure group Watch dog Advisory council Enforcing the environmental laws 7. Explain biosphere? The part of lithosphere, hydrosphere and atmosphere in which living organisms live and interact with one another is called biosphere
Environmental Science and Engineering
UNIT 2: ENVIRONMENTAL POLLUTION ENVIRONMENTAL POLLUTION-DEFINITION:Any undesirable change in the physical, chemical or biological characteristics of any component of the environment (air, water, soil) which can cause harmful effects on various forms of life or property. Types of environmental pollution:a) Air pollution b) Water pollution c) Soil pollution d) Marine pollution e) Noise pollution f) Thermal pollution g) Nuclear hazards a)AIR POLLUTION: It is an atmospheric. condition where certain substances are present in conc. which can cause undesirable effects on man and his environment. Ex. Gases, particulate matter, radioactive substances etc. Gaseous pollutants – sulphur oxides, nitrogen oxides, carbon oxides, volatile organic compounds Particulate pollutants – smoke, dust, soot, fumes, aerosol, liquid droplets, pollen grains Radio active pollutants – Radon 222, Iodine 131, Sr 90
Environmental Science and Engineering Sources of air pollution
Natural sources
man made sources(anthropogenic)
1. Volcanic eruption 2. Forest fires 3. Biological decay
thermal power plants (fly ash, SO2) industrial units vehicle emission(CO-77%, HC-14%, NOX-8%)(Heavy duty diesel vehicles- more NOX and SPM Petrol vehicles – CO & HC)
4. Sea salt spray 5. Pollen grains of flowers
fossil fuel burning Agricultural activities Metallurgical plants (SO2, CO2) Fertilizer plants Textile mills Refineries Paper and pulp mills
Classification of air pollutants: Air pollutants
According to origin According to state of matter
Primary pollutants
secondary pollutants
(SO2, NOX, smoke) (PAN, SO3, aldehydes) Gaseous air
particulate air
pollutants (CO2, NOX)
pollutants (dust, mist)
Environmental Science and Engineering Indoor air pollution: Radon is an important air pollutant. It can be emitted from building materials like bricks, concrete, tiles etc. which are derived from soil containing radium. Burning of fuel produce pollutants like CO, SO2, soot and many other like formaldehyde, benzo(a)pyrene (BAP) are toxic and harmful for health. BAP is also found in cigarette smoke and is considered to cause cancer. A person using wood as fuel for cooking inhales BAP equivalent to 20 packets of cigarette a day. Effects of air pollution: Effects on human: Human respiratory system has a number of mechanisms for protection from air pollution. Bigger particles (> 10 micro m) can be trapped by the hairs and sticky muscus lining in the nose.
S. No. Pollutant
Sources
Effects on human
1
Aldehydes
Thermal Irritates nasal and respiratory tracts decomposition of fats and oils
2
Ammonia
Chemical processes, Upper respiratory passage dye making, explosives and fertilizers
3
Arsenic
Coal and oil furnaces
4
Carbon Monoxide Motor exhausts, oil damages lungs and heart and coal furnaces
5
Cadmium
oil and coal furnaces
Damages kidney
6
Chlorine
Chemical industries
Attacks respiratory tracks, mucous membranes
7
Hydrocarbons
Unburnt vapours
8
Hydrogen Sulfide
Sewage refineries
9
Nitrogen oxides
Motor exhaust
Damages kidney, cause jaundice, lung and skin cancer
gasoline Fog formed with combination of NOx affects respiratory system treatment, Irritates eyes, causes nausea, bad odour vehicle Bronchitis
Environmental Science and Engineering 10
Ozone
Photochemical reactions
Eye irritation, aggressive asthma
11
Sulphur dioxide
Coal and combustion
oil Obstructs breathing, irritates eyes
12
Suspended solids
Industrial manufactures
Eye irritation, asthma, suffocation, lung cancer
air
Control of air pollution: 1. 2. 3. 4. 5. 6. 7. 8. 9.
Using non conventional energy Using bio filters Planting more trees Reducing vehicle exhausts Using less polluting fuels Using mass transport Removal of particulate matter using electrostatic precipitator, cyclone filter etc. Setting of industries of EIA Removal of NOX from vehicle exhaust
b)WATER POLLUTION: Presence of foreign impurities (organic, inorganic, biological) in such quantities so as to constitute a health hazard by lowering the water quality and making it unfit for use. Causes: Point source Ex: flow of water pollutants from sewerage system, industrial effluent etc. Non-point source Ex: agricultural land (pesticides, fertilizers, mining, construction sites) Classification of water pollutants: 1. 2. 3. 4. 5. 6. 7.
suspended matter thermal discharge pathogens (bacteria, fungi, protozoa fungi) natural organic pollutants synthetic organic pollutants inorganic chemicals radioactive waste, oil, sediments
Environmental Science and Engineering Effects of water pollution 1. Objectionable colour and odour is unacceptable and unsuitable for drinking and other purposes. 2. highly turbid and very hard water is unpleasant to drink, food processing 3. acid and alkaline water cause serious health problem 4. water borne infectious enteric disease like typhoid, cholera, dysentery, are the predominant health hazard arising from drinking contaminated water 5. radioactive pollution enter human body through food and get accumulated in thyroid gland, liver, bones and muscles 6. biodegradable waster deplete D O in the receiving stream, affect the flora cause creates anaerobic conditions 7. non biodegradable waste and pesticides travel the food chain and ultimately reach human where they accumulate in fatty tissues 8. thermal discharge in stream depletes D O 9. phosphate, nitrate, promote the growth of algae and encourage eutrophication 10. Industrial effluents result in addition of poisonous chemicals such as arsenic, mercury, lead may reach human body through contaminated food. Control measures of water pollution 1. lay down standard for a. drinking water b. disposal of waste water into water course/sewer/land 2. monitoring 3. treatment a. domestic treatment screening sedimentation filtration, pH adjustment disinfection b. waste water treatment preliminary treatment primary treatment secondary treatment advanced treatment
Environmental Science and Engineering C) SOIL POLLUTION:The contamination of soil by human and natural activities which may cause harmful effects on living beings. Causes:
Industrial waste Urban waste Agricultural practices Radioactive pollutants Biological agent
Effects: Affect human health Affect soil fertility Reduce soil productivity Cause abnormalities Control measures:
Properly collect solid waste Microbial degradation Recovery of products from waste For methane generation, use cattle dung For biogas generation, use biodegradable organic waste
d) MARINE POLLUTION:The discharge of waste substances into the sea resulting in harm to living resources, hazards to human health, hindrance to fishery and impairment of quality for use of sea water. Causes: Sources:
Rivers Catchment area Oil drilling and shipment.
Effects:
waste disposal oil spill thermal pollution (plants located nearby coastal areas) ship breaking activities aquaculture practices nuclear test conducted in seas and oceans
disturb entire aquatic or marine ecosystem oil has suffocation effect on most aquatic animals
Environmental Science and Engineering
smaller animals can be caught in oil envelope and die thermal Pollution may increase the temp. of water and DO may be depleted which causes danger. There may be chances for bioaccumulation and bio magnification in the food chain due to the disposal of non-degradable wastes Oil promotes anaerobic conditions by preventing diffusion of oxygen from air Disposal of radio active wastes cause chronic, acute and genetic damage Affects the recreational activity along the beaches Affect sensitive flora and fauna Loss of buoyancy Affect phytoplankton, zooplankton, algal species, coral reefs, fish, birds and mammals. Control measures: Ban to dump the toxic, hazards waste and sewage sludge. Prevent sewer overflows Minimize coastal developmental activities Oil ballast should not be dumped into sea. e) NOISE POLLUTION:Sound is mechanical energy from a vibrating source Unpleasant and unwanted sound is called noise Sound can propagate through air, liquid or solid Sound is pressure perturbation in the medium through which it travels. Sound pressure creates alternate compression and rarefaction. The number of c and r per unit time is called frequency. Sound pressure does not produce linear impact on human. A logarithmic scale has been devised. Noise is measure in terms of SPL which is a log ratio of sound P to a std. P. It has a dimensionless unit decibel (dB). The international reference P is 2X10 power -5 Pa. Sound can affect ears either by loudness or by pitch (frequency). The CPCB has recommended the permissible noise levels for various places.
Environmental Science and Engineering Area
Permissible noise level(dB) Day
Night
Industrial
75
70
Commercial
65
55
Residential
55
45
Silent Zone
50
40
Sounds and their decibel scale: 1. Rocket engine – 180 dB 2. Jet plane take off – 150 dB 3. Threshold of pain – 140 dB 4. Recorded music (max) – 130 dB 5. Construction works, news paper press – 100 dB 6. Motor cycle – 90 dB 7. Ordinary conservation – 70/80 dB 8. Air conditioning unit/ Light traffic – 60 dB 9. Normal living room – 50 dB 10. Library or soft whisper – 30 B 11. Threshold of hearing – 0 dB Sources of noise pollution: 1. Industrial units 2. Transportation modes 3. Construction activities 4. Celebrations 5. Electric home appliances Nanjing – 105 dB Rome
– 90 dB
Calcutta
– 85 dB
Mumbai
– 82 dB
Delhi
– 80 dB
Effects of noise pollution: Interferes communication Hearing damage (90 dB) Physiological and Psychological disorders
Environmental Science and Engineering
Noise pollution during Diwali: The environmental (protection) (2nd amendment) Rule 1999 has given the permissible limit of noise level produced from fire crackers to be 125 dB. According to recent test reports on fire crackers by National Physical Laboratory, the fire crackers available in the market produce noise beyond the permissible limit. Atom bomb – 135-138 dB Hydrogen bomb –
”
The Union Government and all the state governments shall follow the guidelines of amendment 89 of env. (Protection) Rule 1986 framed under Env. (Protection) Act 1986 which says 1. The manufacture, sale or use of fire crackers generating noise level exceeding125dB shall be prohibited. 2. For joined fire crackers the limit is taken as 5log 10 (N) dB; where N= no. of crackers joined together 3. The use of fire crackers shall not be permitted except between 6.00a.m and 10p.m. 4. No crackers burning is permitted in/near silent zone – areas near hospitals, educational institutions, courts, religious places, etc. 5. The State Education Resource Centre shall take appropriate steps to educate students about the ill effects of air and noise pollution. Control of noise pollution:
Reduction in source of noise] Noise making machines should be kept in containers with sound absorbing media Proper oiling will reduce noise from machinery Using silencers – fibrous material Planting trees Legislation can prevent excess sound production, unnecessary horn blowing etc.
f) THERMAL POLLUTION:Addition of excess undesirable heat to water Causes: Nuclear power plant Domestic sewage Hydro electric power Effects:
Reduction inn dissolved oxygen Increase in toxicity
Environmental Science and Engineering Direct mortality Control measures:The following methods should be adopted to control thermal pollution
Cooling towers Cooling ponds Spray ponds
g) NUCLEAR HAZARDS:- OR RADIO ACTIVE POLLUTION The physical pollution of air, water and soil by radio materials. Causes:I) Natural causes: Solar rays Radio nuclides in earth‟s crust Environmental radiation II)Anthrogeneic causes:
Medical X-rays Radio isotopes Nuclear test Nuclear installations Nuclear reactor
Effects: Causes skin burns, loss of teeth, vomiting anemia Blood cancer Brain damage Control measures:
Radiation exposure protection Radiation contamination protection Controlled area Disposal of radioactive waste
SOLID WASTE MANAGEMENT:Any material that is thrown away or discarded as unwanted is considered as solid waste. Types: Garbage or food waste Rubbish Agricultural waste
Environmental Science and Engineering Industrial waste Hazardous waste Cause: Over population Affluence Technology Effects: Health hazard Environmental impact Control measures:Solid waste management include the waste generation Solid waste generation
Collection of waste
Transportation
Storage Segregation of waste
Disposal methods
Land fills
Incineration
Composting
Collection of solid waste Disposal of solid waste Land fill- Disposal of municipal waste in the upper layers of the earth‟s mantle. Incineration- Burn highly combustible wastes at very high temperature, Composting or Bio degradation- Decompose the organic components of the municipal solid wastes.
Environmental Science and Engineering Waste utilization o Reuse o Recycling o Reclamation Role of an individual in prevention of pollution;-
Use stairs instead of elevators Use public transportation walk or ride a bicycle Plant trees around building Turn off lights, television sets and computer when not in use. Pay immediate attention to leaks in pipes. Install waste saving equipments. Recycle glass metal and paper. Compost garden waste Segregate waste and recycle Buy locally made long losing material Buy environmentally degradable products. Take some bag from home to market to purchase.
POLLUTION CASDE STUDIES:1. Bhopal gas tragedy:- (Air Pollution) Pesticide factory-Union Carbide- corporation leak large volume of methyl iso cyanate –atmosphere Bhopal- India-midnight on December 3,1984-city- changegas chamber-within a week 10,000 people died – 1000 people turned blind-lakhs of people still continue to suffer various diseases 2. Gulf War: (Marine Pollution) Gulf war was fought between Iraq and US-Period of 6 weeks in 1991-American fighters dropped a lakh of bombs-force the Iraq army to withdraw from Kuwaitretreat of Iraq-burning of 700 oil wells-near sea shore –oil from well spills out into the sea-the floating oil oversea water nearly 80 km long-burning of oil wells nearly 10 months-released huge amounts of pollutants likeCO2 and SO2 into the atmosphere-1 million birds killed. 3. Chernobyl Disaster : ( Nuclear pollution) Occur at Chernobyl in USSR 28 th April,1986-the reactor exploded- result of uncontrolled nuclear reactions-radioactive fuel spread out in to the surrounding areas –killed at least 20,000 people-damage to soil, water and vegetation around 60 km. 4. Minamata Disease :( Marine Pollution) Minamata- Small hostel village in Japan –Chicago-chemical company produces Venyl polymer plastics-industry release its effluent into Minamata sea-Effluents
Environmental Science and Engineering containing mercury ions-converted into methyl mercury- highly toxic consumed by fishes –affect human being through food chain-damage central nervous system-loss of vision and hearing-loss of muscular coordination and severe headache- nervous disorders DISASTER MANAGEMENT; FLOOD: Submergence of waste areas of land under water for many days in continuation Causes: 1.Heavy rainfall 2. Sudden Snow melt 3. Clearing of forest for agriculture 4, Industries increase the value and rate of water discharge after a storm Effects: 1. Damage to building and property 2. Soil erosion is the major loss of agriculture 3. Any product submerged by flood water cannot be rescued Control measures: 1. Building wall prevent spilling out the flood water over flood pains 2. advance meteorological information will prevent flood damage 3. reduction of run off by increasing infiltration through appropriate forestation eg.flood in Bangladesh 1974 EARTHQUAKE: Earthquake is the motion of the ground surface caused by wave motion starting from a focal point Causes: 1. Underground nuclear testing 2. Volcanic eruption 3. Pressure of manmade dams, reservoir and lakes 4. movements of plates of earth Effects: 1. Cause Tsunami 2. Deformation of ground surface 3. In hilly and mountain areas may cause land slides which damage the settlement and transport system 4. Depending on the severity of the quake collapses house and people died in 1000 eg. Earthquake in Bhuj town
Environmental Science and Engineering Control measures: 1. Government can inform the earthquake prone zone and caution residence 2. building should be designed to withstand tremors CYCLONE: Cyclone is meteorological phenomena intense depressions forming over the open oceans and moving towards the land Effects: 1. Depends on the intensity of the cyclone 2. Damage to human life crops roads, transport, communication could be very heavy Control measures: 1. planting more trees on hostel areas 2. construction of dams 3. Radar system is used to detect cyclone eg.Cyclone in AP LANDSLIDES; The movement of eart materials like coherent rock, mud, soil and debris from higher region to lower due to gravitational pull is called landslide Causes: 1. Earthquake, shock, vibration 2. Deep water ground mining 3. movement of heavy vehicles on the unstable sleepy region Effects: 1. Increase erosion of soil 2. block the roads 3. damage the houses, crop yield, life stock Control measures: 1. Planting of deep rooted vegetation 2. Encouragement for construction of bridges water ways 3. Create national parks, sanctuaries biosphere.e.g.land slides in U.P
Environmental Science and Engineering Review questions 1. Give any three methods of air pollution control equipment Catalytic converters Cyclone collectors Electrostatic precipitators 2. What is smog? It is a mixture of smoke and fog which forms droplets that remain suspended in the air.
3. What is point source of water pollution? Point source is discharge pollutants at specific locations through pipes, ditches into bodies of surface waters. 4. When a sound causes noise pollution? Noise beyond 120 dB 5. What are the types of solid waste? Municipal waste Industrial waste Hazardous waste What is waste minimization? Industrial manufacturing system the primary concern should be reducing the quantities of waste materials produced. This avoids the necessity to threat and disposal off such materials. 6. Name the chemical constituent of gas that caused death in Bhopal gas tragedy in India. Methyl iso cynaide. 7. Define the term Tsunami. It is a large wave that are generated in a water body where the sea floor deformed by seismic activity. This activity displaces the overlying water in the ocean
Environmental Science and Engineering UNIT 3:NATURAL RESOURCES Any component of the env. Which has intrinsic value of its own is called as resource. Any component which can be transferred in a way such that it becomes more valuable and useful is termed as resource.
Resources Renewable
Non renewable
Eg. Clean air, clean Ground water minerals Considered to be renewable with considerable life span-as long as they have the capacity to renew – unless they are affected by catastrophes or anthrophogenic activity.
Continuous
Extrinsic
water, Solar energy, wind Human skills energy
Available only in Considered to be finite quantity – available always. their rate of renewal is so slow that they are considered as non-renewable
FOREST RESOURCES: Forests are one of the most important resources of the world. Apart from having high commercial importance they provide high environmental services also. They act as a blanket on the surface of the earth. Around 1/3rd of world land area was found to be forests. 1/5 th of world forests were found in Brazil and 6-7% was in Canada and USA. But the matter under high concern is the declination of forest cover year by year. USES OF FOREST: Commercial uses: Forests provide timber, fire wood, food material, resin, gum, non edible oils, drugs, medicine, rubber, fibers, bamboo and many other important items. Ecological uses: 1. 2. 3. 4.
Production of Oxygen: Photosynthesis – earth‟s lungs Reducing global warming – sink for carbon di oxide Wild life habitat – 7 million species in tropical forests alone Regulation of hydrological cycle – prevent surface run off – giant sponges – 50-80% moisture
Environmental Science and Engineering 5. Soil conservation – hold solid particles tightly and prevent soil erosion – wind breaks 6. Pollution moderators: absorb toxic gases and purify air reduce noise pollution OVER EXPLOITATION OF FORESTS: Human beings depend heavily on forests for food, shelter, wood, fuel and medicine with growing civilization etc. shooted up resulting in large scale mining, road building and clearing of forests. Excessive use of charcoal, fuel wood, expansion of urban, agricultural and industrial areas and overgrazing have lead to over exploitation and rapid degradation of forests. DEFORESTATION: The total forest area of the world in 1900 was 7000 million hectares -1975 – 2900 mha – 2000 – 2300 mha. Deforestation rate intemperate countries are relatively moderate. But it is alarming in tropical countries. It is estimated that in next 60 years we would lose more than 90% of our tropical forest. INDIAN STATUS: Stabilized since 1982, with about 0.04% declaration per year between 1982 - 90. During this period it is estimated that about 1.44 mha land was brought under afforestation. As per our NFP, we have a target of achieving 33% forest area. But we still have only 19.27% of our land area covered by forests(satellite data). MAJOR CAUSES OF DEFORESTATION: 1. Shifting of Cultivation – 300 million people – 5 lakh hectares of forest for slash and burn culture 2. fuel requirement 3. raw materials for industrial use 4. developmental projects 5. growing food needs 6. overgrazing CONSEQUENCES OF DEFORESTATION 1. 2. 3. 4. 5.
threatens many wild life species due to destruction of natural habitat biodiversity is lost along with that genetic diversity hilly regions are made prone to landslides soil erosion and loss of soil fertility hydrological cycle is affected (loss of rainfall, flood, drought etc)
Environmental Science and Engineering TIMBER EXTRACTION AND MINING: The major activities in forest area are 1. timber extraction 2. mining The important effects of timber extraction are i) thinning of forests ii) loss of biodiversity, particularly tree breading species iii) soil erosion and loss of soil fertility iv) migration of tribal people from one place to another in search of new forest v) extinction of tribal people and their culture MINING: Mining is a process of removing ores from area which is very much below the ground level. Mining is done for the extraction of several minerals of metals like Fe, Mn, Au, Ag,etc. The minerals are especially found in thick forests. Mining can be carried out in two ways 1. Surface mining 2. underground mining or sub-surface mining The effects of under ground mining on forest reserves is comparatively less than that of surface mining Relation between forest and climate change: Forests both influence and influenced by climate change. They play an important role in the carbon cycle and the way we manage forests could significantly affect global warming. Forests hold more than 50 per cent of the carbon that is stored in terrestrial vegetation and soil organic matter. Hence, deforestation contributes significantly to net emissions of carbon dioxide into the atm. If the predicted global warming occurs, the impact on forests is likely to be regionally varied, dramatic, and long-lasting. Even now, we can see how any extreme weather has great impact on forests. For example, the 1999 storms in Europe caused heavy damage to forests and also to trees outside forest areas. The Kyoto Protocol on climate change may have a great impact on forest management. Under the Protocol, a country with forests earns emission credits, since its forests absorb carbon dioxide. These credits are tradable, that is, a developing country can sell its credits to an industrialized country that has exceeded its quota of emissions. The latter would invest in afforestation and reforestation projects in the developing country.
Environmental Science and Engineering DAMS – BENEFITS AND PROBLEMS River valley projects with big dams are considered to play a key role in the development of a country. India has large number of river valley projects 1. These dams are regarded as symbol of national development. 2. provides large scale employment of tribal people and increase the std. of living of them 3. contribute for economic uplift and growth 4. help in checking flood 5. generate electricity 6. reduce power and water shortage 7. provide irrigation water 8. provide drinking water to remote areas 9. promote navigation and fishery. Environmental problems: The environmental problems can be at upstream as well as downstream Level Upstream problems 1. 2. 3. 4. 5. 6. 7. 8.
Displacement of tribal people Loss of flora and fauna siltation and sedimentation near reservoir stagnation and water logging near reservoir growth of aquatic weeds micro climatic changes RIS causes earthquakes breeding of disease vectors
Downstream problems 1. 2. 3. 4. 5.
Water logging and salinity due to over irrigation micro climatic changes salt water intrusion at river mouth loss of fertility due to sediment deposits out break of vector born diseases.
Environmental Science and Engineering WATER RESOURCES Water is an indispensible resource. Around 97% of world surface is covered with water. Most of the animals and plants have 60-65% of water in their body. Unique features of water 1. High specific heat 2. High latent heat of vapourisation 3. Good solvent for oxygen, nutrients and pollutants 4. Anomalous expansion on freezing 5. High surface tension Global distribution of water is very much random depending on the geographical conditions. The availability of water decreases in the following order. 1. Tropical rain forest 2. Temperate regions 3. Deserts Water is used for domestic, irrigation and also industrial purposes Out of the total available water 75% is used for agriculture, 20% for industrial usage. In our country ~93% of water is used for agricultural purposes. Ground water: 9.86% of fresh water is ground water and it is 35-50% greater than surface water. Aquifer: The layer of soil which is permeable has the ability to store water is called an aquifer. It is generally made up of gravel, sand etc. Unconfined aquifer: it is covered by permeable layer. The recharge of this layer is by rainfall or snowmelt. Confined aquifer: sandwiched between impermeable layers. The recharge is through unconfined aquifer layers. Over utilization of ground water: Over utilization of water leads to rapid depletion of water resources, ground subsidence, lowering of water table and water logging. Effects of over utilization of ground water: Reasons: Economic development, rapid industrial growth and population explosion The use of ground water and surface water rates which are higher than that of recharge ultimately leads to
Water scarcity Water logging Salination alkalization
Environmental Science and Engineering
water pollution or contamination
creates declining of water levels crops failure and reduction in agricultural production over pumping of ground water create drought, famine and food shortage over pumping of ground water sea water intrusion in coastal aquifers land subsidence may due to over pumping of ground water river pollution due to industrial activities and dumping of waste into rivers, which in turn force to utilize the ground water, ultimately leads to over pumping Clean water is universal right. It is the responsibility of everyone to ensure the purity of water. Water is a valuable commodity and it has to be conserved.
Surface water: When evaporation and transpiration rates are lower than the rainfall, surface water body like lake, river, pond, streams etc. are formed. Flood: over flow of water, whenever the water in flow is greater than the carrying capacity of the channels flood occurs. Causes: 1. heavy rainfall, snow melt, sudden release of water from dams. 2. Prolonged down pour leading to overflowing of rivers and lakes 3. Reduction in carrying capacity due to obstructions or sediments etc. 4. Deforestation, overgrazing, mining increases water run off 5. Removal of dense forests from hilly regions Effects: 1. Submerges the flooded area 2. Loss of soil fertility due to soil erosion 3. Extinction of civilization at costal area Flood management: 1. 2. 3. 4. 5.
Dams and reservoirs can be constructed Embankments and proper channel management Flood way should not be encroached Forecasting or flood warning Decrease of run off by infiltration through afforestation or rain water harvesting etc.
Environmental Science and Engineering Drought : Unpredictable delay in climatic condition occurring due to monsoon rain failure. Types: Meterological : in order of month or year, actual moisture supply at a given place consistently falls below critical level. Hydrological: deficiency in surface and subsurface water supplies Agricultural: inadequate soil moisture to meet the need of a particular crop at particular time or susceptibility of crops during different stages in its development Socioeconomic: reduction in the availability of food and social securing of people Causes:
Deforestation and lesser rainfalls coupled with cutting of trees for timber leads to desertifictation.
Over drafting of ground water, subsidence of soil, drying of wetlands
Pollution of soil with solid waste, industrial effluents etc makes land useless and dry
Population explosion in man and livestock leads to enhanced requirement of timber, fuel wood, grazing
Shifting cultivation
Effects:
Increase of water in stream pond
Ground water table get declined
Loss of agricultural crops
Loss of biodiversity
Government spent a lot of money as drought relief f und
Control measures
Rain water harvesting
Watershed management
Prevent deforestation
Encourage afforestation
Environmental Science and Engineering CONFLICTS OVER WATER Due to increase in population and decrease in water resources conflicts over water starts Conflicts over the water around world was classified as
Control of water resources
Military food resources
Political resources
Terrorism
Military targets
Development disputes
Causes:
Conflicts through use 1. Shipping traffic in international water .2 dam construction
Construction of power stations on
Conflicts through pollution-rhine river,Europe
Distributional conflict-relative storage
Euphrates, Nile, Ganges - plataneous in upper basin, reduced in lower basin due to extensive use.
Anatolian dam project by turkey Farakka dam in India Distributional conflict: Absolute shortage. Colorada and Rio Grande, Jordan
Conflicts management:
Enact laws to check practices to control water pollution
Sharing river solved by interlinking river
Power must be given to national water authority and river basin authority and river s-basin authority for equitable distribution of basin waterdemand fo0r nationalization of water needs
Environmental Science and Engineering MINERAL RESOURCES Environmental impacts of over extraction of mineral resources: Depending on the conditions of terrain and depth of ore deposits 2 types of mining operations are carried out. 1. open cast mining and 2. underground mining. In both types each steps in mining processing produce several environmental effects such as, Deforestation takes place due to removal of vegetal covers. Great volume of debris has been generated which disrupt the surface and ground water circulation. It also reduces the water carrying capacity of streams very close to mining area The stacking of over burden and building of soil banks creates problems of landslides Under ground fire in coalmines is a hazard that is difficult to control Mining and ore processing normally causes air pollution and water pollution The acid water generated in coalmines can pose a serious problem of water pollution, which adversely affects the flora and fauna. Deeper excavation of ground causes lowering of water table, which leads to drying of wells or sea water intrusion In stone quarries, blasting of rocks not only annoying the people nearby, but also cause hazard from fly rocks and dusts and damage to buildings due to vibrations The disposal of waste material produced after concentrations of ore create increase concentration of heavy metals and toxic elements in the environment. FOOD RESOURCES: PROBLEMS FACED BY FOOD RESOURCES
Overgrazing
modern agriculture
Land degradation
high yield variety crops
Soil erosion
micronutrients imbalance
Loss of useful species
nitrate pollution Eutrophication Pesticide related problems Water logging Salinity
Environmental Science and Engineering WORLD FOOD PROBLEMS:
Problems mainly under nutrition and malnutrition Natural calamities:-famine, drought, earthquake, flood, gale, storm Disease and medical facilities Pest damage:-insects, bacteria, viruses, parasites consume 60% of world‟s food production Hunger Population explosion in rural areas Environmental pollution Lack of water for irrigation Less rainfall due to deforestation Livestock overgrazing Overfishing
CHANGES CAUSED BY OVERGRAZING AND AGRICULTURE: Overgrazing: Process of eating away the vegetation along with its roots without giving a chance to regenerate
Land degradation-leads to organically poor, dry, compacted soil cannot be used for further cultivation Soil erosion-cover of vegetation gets removed from soil Loss of useful species-good quality grasses and herbs with high nutritive value, when grazed lose even the root stocks which carry the reserve food for regeneration get destroyed which gives raise to secondary species like parthenium, Lantane, Xanthium etc To prevent –match the forage supplement to the herd‟s requirement.eg.Switch grass Modern agriculture: The practice through which specific plant species are cared and managed so as to obtain maximum yield of consumable parts of plants –agriculture Makes use of hybrid seeds and selected and single crop variety, high tech equipment and lots of energy subsides in the form of fertilizers, pesticides and irrigation water e.g. green revolution Damage to soil Water contamination Water scarcity Global climate change Water logging-results when soil is over irrigated Soil salinity-increase plant productivity, interferes with water uptake by plants Fossil fuels and pesticides produce air pollution Impacts related to high yielding varieties:
Monoculture ie the same genotype is grown over vast areas. Disease spread easily Micronutrient imbalance e.g Zinc deficiency-affect soil productivity
Environmental Science and Engineering
Nitrate pollution-nitrogenous fertilizers applied deep soil contaminates ground water. cause blue baby syndrome methaemoglobinemia- affects infants Eutrophication: Over nourishment of lakes due to agriculture field wash out-leads to algal bloom-dead organic matters increases due to decomposition-leads to oxygen demand Problems associated with pesticide use:
Evolution of genetic resistance Imbalance in ecosystem Creation of new pest Persistence, Bioaccumulation and Biomagnification Mobility through soil, water, air, washed away into rivers, streams, when it rains can harm fishes Creating super pest Death of non starget organisms Salinity Water logging
Water logging / salinisation: Saturation of soil with irrigation water or excessive precipitation. So that water table rises close to surface. Water logging results when soils are over irrigated without drainage. Occurs in clayey soil, soil root zone becomes saturated with so much water blocking oxygen supply for growth and soil becomes unsuitable. Carbondioxide and ethylene accumulate around roots and affects plants ENERGY RESOURCES Growing energy needs: Population explosion, Luxurious life, Industries, Agriculture, mining, transportation, lighting, cooling, heating, building all need energy. Fossil fuels like coal, oil, natural gas produce 95% of energy Sources of energy PrimaryRenewable energy-resources which can be generated continuously in nature and are in exhaustible and can be used again endlessly.wood, Tidal, Solar, wind, hydropower, biomass, biofuel, geothermal, hydrogen Non – renewable energy- Resources which have accumulated in nature over a long span of time and cannot be quickly replenished when exhausted.coal, petroleum, natural gas Secondary-petrol, electrical energy, coal burning
Environmental Science and Engineering
Energy renewable
Advantage
Energy non renewable
1. Wide availability 2. Low cost 3. Decentralized power production 4. Low pollution 5. Available for the future 1. Available in high concentrated form 2. Easy to store 3. Reliable supply 4. Lower cost
Disadvantage 1. Unreliable supply 2. Produced in small quantity 3. Difficult to store 4. Cost more
1.highly pollution Available only in few places High running cost Limited supply and will one day get exhausted
Use of alternate energy sources: Refers to energy sources which are not based on the burning of fossil fuels or the splitting of atoms. Solar energy: Total energy from sun per year-35,000 times the energy used by man Used to run car, power plants and spaceships Energy harvesting devises: Solar heat collectors Solar cells „ Solar cooker Solar water heater Solar furnace Solar power plants Wind energy: Average wind velocity of earth -9 m/sec and power produced when a windmill is facing the wind od 10 miles/hr-50 watts.eg.largest wind farm-Kanyakumari in tamilnadu is generating 380 MW electricity
Environmental Science and Engineering Hydro power:
Comes from damming of rivers and utilization of high pressure, its kinetic energy is transformed into turbine blades and used to generate electricity
Minimum water falls height-10 m
Hydro power potential of India-4x1011KW/Hr
Tidal Energy Uses the natural motion of tides to fill reservoirs which are then slowly discharged through electricity producing turbines Ocean thermal energy Energy available due to the difference in water temperature. The surface of the tropical ocean and at deeper level is called OTE. A difference of 20 0c or more is required for operating OTE power plants. Geothermal energy Energy harassed from the hot rocks inside earth. eg. natural geysers in Manikaran,kully,sohana Biomass energy Organic matter produced by plants Types: 1.Energy plantations: Solar energy is trapped by green plants through photosynthesis and converted to biomass e.g Leucaema,Sugarcane, sweet sorghum, Sweetbeet aquatic weeds like hyacinth, Sea weeds,potato,cereal-energy plantations Produce energy by burning directly or by getting converted into burnable gas or converted to fuels by fermentation. Petro crops Latex containing plants Euphorbias, oil palms rich in hydrocarbons and yield oil like substance under high temperature and pressure-refined to form gasoline LAND RESOURCE Land is critically important national resource which supports all living organisms including plants and animals. The soil profile of land determines its ability to serve socio-economic needs. It has been estimated that more than 5000 million tonnees of top soil is eroded annually along with 5 million tones of nutrients. „About 1/3 of this is lost in sea while the rest in reservoirs and rivers leading to flood.
Environmental Science and Engineering About 38% of the area in India suffers from moderate to high degree of water based erosion. The per capita availability of land in the country has declined from 1.37 hectare in 1901 to 0.33 hectare in 2000. All these lands cannot be utilized for agricultural purpose. Some land would be required for other activities (to maintain urban area). Effective steps have to be taken for preventing diversion of land suitable for sustainable farming to non-farm uses. Simultaneously, degraded lands and waste lands have to be improved by ecological restoration. The Department of Land Resources was setup in April 1999 by ministry of Rural Development to act as nodal agency for land resource management. Land Degradation: Land degradation is defined as the reduction in soil capacity to produce in terms of quality, quantity goods and services. The definition is also based on 1. sustainability or ability to produce continuously and indefinitely. 2. quality of land resource that makes it sustainable or resistant to degradation 3. carrying capacity or the number of people and animals the land can normally support without significant stress. Landscapes generally undergo degradation but are usually compensated by nature‟s inherent recovering ability. Whenever degradation occur exceeding nature‟s restorative capacity, the result will be a disaster. Man induced landslides: The hill slopes are prone to land slides, landslips, rockslides etc. These hazardous features have reduced the overall progress of the region as they obstruct the roads, communication media and water flow. There are two types of slides 1. slides due to natural factors 2. slides induced by man and his activities Some of the human activities that cause land sliding are
massive deforestation erratic agricultural practices road building Unscientific quarrying etc. Engineering. Constructions
Soil erosion: 1. Terracing: Terracing reduces soil erosion on steep slopes by concerting the land into a series of broad, level terraces. This retains water for crops at each level and reduces soil erosion by water run off. 2. Contour Farming: This method is adopted for gently sloped land. This involves planting crops in rows across the contour of gently sloped land.
Environmental Science and Engineering 3. Alley Cropping or Agro forestry: In this method crops are planted together in strips or alleys between trees and shrubs that can provide fruits and fuel wood. The trees and shrubs provide shade which reduce water loss by evaporation and preserve soil moisture. Wind Breaks or Shelter Belts: Wind breaks and shelter belts or trees are established to reduce wind erosion and also for retaining soil moisture. ROLE OF INDIVIDUAL IN CONSERVATION OF NATURAL RESOURCES: Natural resources-forest,water,soil,food,mineral and energy Overuse of these resources cause problems Conserve water: Don‟t keep water taps running Install water saving toilets Check forwater leaks Reuse soapy water Use drip and sprinkling irrigation Conserveenergy Turn off lights,fan when not in use Use solarcooker for cooking Try riding bicycle Protect soil: Don‟t uproot plants Grow grass which binds soil andprevent erosion Make compost Use green manure Don‟t over irrigate Use mixed cropping EQUITABLE USEOF RESOURCES FOR SUSTAINABLE IFE STYLE:
Most developed countries like USA, Canada, Japan, Australia have 22% of natural resources, use 88%.73%of its energy and command 85%of its income Less developed countries has 78% of population, 12% Usage of natural resources, 27% of energy, 15% of income Gap arises due to increase in population distribution of resources and wealth Problem solved by equitable distribution of resources and wealth Global consensus has to be reached for more balanced distribution of basic resources like safe drinking water, food, fuel etc. So poor low developed countries able to sustain their life Two basic cause of unsustainability are over population in poor countries and over consumption of resources by rich countries generate wastes Rich countries lower down their consumption level Poor countries fulfilled by providing them resources
Review questions
Environmental Science and Engineering 1. What is artesian well? A well or hole in aquifer flows freely at the surface 2. What is wetland?give examples and use Wetlands are the natural water storage bodies on ground surface Eg.Swamps, Meadows, Marshes 3. State the major process which have major environmental impact while processing of minerals. Smelting,chemical extractions 4. What is salinization? During over irrigation, all the water is not absorbed in the soil. such water evaporates leaving behind a thin crust of dissolved salts in the top soil. 5. Give two examples of primary and secondary sources of energy? Primary source-fossil fuels, hydro energy Secondary source-petrol, electrical energy 6. What is ocean thermal energy conversation? In oceans, a thermal gradient (i.e., the temperature difference) of about 200C exists between surface water heated by sun and colder deep water. This difference can be harnessed to produce power. This concept is OTEC. 7. Give any four environmental benefits of dam
Source of cleaner and safer power
For irrigation of agricultural lands
Helps in recharging of ground water
Habitat for many fishes and wildlife
8. What are the sources of water Ground water, surface water, sea water, rain water 9. What is sardar sarovar Narmada project? It is a multipurpose project on river Narmada, bringing the benefits of irrigation, power and drinking water to Gujarat, Mathya Pradesh and Rajasthan. 10. What is integrated pest management? The process of controlling crop pests using ecological system
Environmental Science and Engineering UNIT 4:SOCIAL ISSUES AND THE ENVIRONMENT From unsustainable to sustainable development: Brundland commission describes sustainable development as the development that meet needs of present generation without compromising ability of future generations to meet their own need Concept of sustainable development
A symbiotic relationship between consumer human race and producer natural system Compatibility between ecology and economics
Aim of sustainable development:
Inter generational equity Intra generational technology
Significance of sustainable development: Developing appropriate technology Reduce , reuse, recycle of natural resources Providing environmental education and awareness Consumption of renewable resources Conservation of nonrenewable resources Population control Urban problems related to energy: Urbanization: Movement of human population from rural areas top urban areas for betterment of education, communication, health, employment etc Causes; Cities are main centers of economic growth, trade, transportation, education, medical facilities and employment Urban sprawl: Urban growth is fast , so difficult to accommodate with their limited area .So cities spread into rural areas
Urban energy requirement: Residential and commercial lighting Public and private transportation Electrical and electronic appliances
Environmental Science and Engineering Solution: Use public transport instead of motor cycles Energy consumption must be minimized Use solar and wind energy Impose strict laws, penalty, and energy audit Water conservation: Process of saving water for future utilization Water source: Fresh water River Stream Pond Ocean Need for water conservation: Population increases water requirement also increases Due to deforestation annual rainfall decreases Over exploitation of ground water Ways of water conservation Reducing evaporation loss Reducing irrigation loss Reuse water Avoid sewage discharge Water conservation method Rain water harvesting Watershed management Rain water harvesting Objective: To meet increasing demands of water Raise water table by recharging ground water Reduce ground water contamination from salt water intrusion Roof top rainwater harvesting Involves collecting water that falls on roof of house Rainwater from roof top, road surface, play ground diverted to surface tank Advantages of rainwater harvesting
Environmental Science and Engineering Increases the well water availability Raise ground water level Minimizes soil erosion Watershed management: It is defined as land area bounded by divide line from which water drains under influence of gravity in to stream, lakes, reservoir. Eg. Pits, dams, Farm, ponds, Himalaya. Types 1. Micro 2. Mini 3. Macro Watershed Management; The management of rainfall & resultant runoff. Forestry Halt deforestation, provide vegetative cover, degraded land and supplement folder and fuel wood resources available to rural communities Agriculture -
Aims to increase agricultural productivity in sustained manner and to diversify crop production - Major objective shall be achieved through organizing farmers, training camps and exposure visits. - Construct check dams, water harvesting tanks, storage tanks and channels , repair of old channels , implementing measures to check soil erosion Horticulture establishment of private orchard Rejuvenation of existing orchards Distribution of horticulture plant for home garden planting. Animal husbandry Energy conservation Community participation Training and awareness programme Advantages of Watershed projects -
Improved access to drinking water in project areas during drought Increase in cultivation area leading to increase in employment Increase in crop yield, resulting better income to rural population Improved availability of fodder for animals and increase in milk yield Increase in employment & involvement of women Increase in net returns from all crops.
Environmental Science and Engineering - Decrease in soil erosion. - Restoration of ecological balance. Resettlement and Rehabilitation of people: Resettlement – simple relocation or displacement of human population. Rehabilitation – making, system to work again by allowing, system to function naturally. Includes replacing the lost economic assets, Safeguard Employment, Provide safe land for building Repair damaged infrastructure. Effects:
Loss of land Loss of recourse Unsatisfactory comp[enasation Social and cultura problems Changes in tradition of indigenous people Spread of disease Submergence of valuable forest Waterlogging Extinction of wild life
Environmental ethics:Over exploitation of forests, land, water as well as various living components of biosphere and failure to tackle the problem of pollution and environmental degradation are exposing the humanly to the thread of a global environment crisis. It emphasis that real development cannot occur unless the strategies which are formulated are implemented are environmentally sustainable. Even though our government is formulating several rules, regulations, policies, laws, it is the duty of each and every one to protect our nature. Therefore human beings are ethically responsible for the preservation of the world‟s ecological integrity. The environment ethics literally means conscious efforts to protect environment and to maintain its stability from the pollutants. Following are some of the ways to safeguard environment. 1. To sacrifice the consumption of some of the good which reduces environment quality 2. Minimize the resource utilization and conservation 3. Adopt sustainable and eco friendly development. (e.g) reduction of waste, recycling, waste management and harvesting non conventional energy If we change as individuals then the society will also change by itself. The society is nothing but an extension of the individual.
Environmental Science and Engineering Green House Effect and Global Warming: The raise of earth‟s surface temperature due to intense green house effect is called global warming. Causes: Over the last century, the level of carbon dioxide in the atm. Has increase by 25%, the level of nitrous oxide by 19% and the level of methane by 100%. These 3 major global warming gases are released into the atm. by burning of fossil fuels, industrialization, mining, deforestation, exhaust from increasing automobiles and other anthropogenic activities. Effects: Increase evaporation of surface water – influence climate change Leads to declining biodiversity Melting of mountain glaciers and polar ice, which cause rise in sea level Change the climate and rainfall – reduction in food production The biological productivity of ocean also decreased due to warming of earth‟s surface With more carbon dioxide in the air, the plants will grow bigger with increase in yield and resulting in the soils getting poor quality 7. If proper precautions are not taken, the conc. Of green house gases may double in the atom. with in next 50 years, and will makes the average global temp. to 45 0 C. 1. 2. 3. 4. 5. 6.
Ozone layer depletion: Ozone is an important chemical species present in the stratosphere. Its conc. is about 10 ppm. It acts as a protective shield for the life on the earth. Ozone is produced and also broken down by photochemical reactions, thus maintaining equilibrium. Causes for ozone layer depletion: 1. Chlorine released from CFC and Bromine released from halogens are the most important chemicals associated with ozone layer depletion 2. The halogens are used in fore extinguishers and CFC are extensively used in air conditioners and refrigerators. 3. Methyl bromide used during packaging of fruits to prevent bacterial action flows out into the atmosphere as soon as the packing is opened. This cause heavy damage to ozone. 4. High altitude aircrafts and chemicals emitted by industrial plants and automobiles. Effects: 1. 2. 3. 4. 5.
Marked rise in cause skin cancer Damage immune system Eye ailment such as cataract Shorter life of paints and plastics Restricted growth and crop damage
Environmental Science and Engineering 6. Destruction of aquatic life Waste land reclamation: Any land which is not put to optimal use is defined as waste land. The waste land do not fulfill their life sustain potential wasteland contributes about 20.17% of the total geographical area of India. Reasons for formation
Over grazing and over exploitation Toxic effluent discharged from sewage and industrial wastes Mining activities destroy forest and cultivable land Use of pesticides also produce wasteland Erosion, desertification, water logging also degrade land
Wastelands can be reclaimed by the following way Conserving the soil – land is brought under vegetal cover. This can be done by growing grasses and shrubs To reclaim the land/soil, effective participation of the people, voluntary agencies and government is very important Consumerism and Waste Products Consumerism refers to the consumption of resources by the people. Early human societies used to consume much less resources. But the consumerism has increased to a very large extent. Consumerism is related to both population size and increase in demands due to change in life style. Population has increased tremendously. World Bank estimates our population to reach 11 billion by 2045. Two types of conditions of population and consumerism exists. 1. People over – population: When there are more people than available food, water and other resources in an area – causes degradation of limited resources – poverty and under nourishments. Low Developed Countries (LDC) are more prone to these conditions. There is less per capita consumption although the overall consumption is high. 2. Consumption over – population: These conditions occur in more developed countries (MDC). Population size is smaller but the resource consumption is high due to luxurious life style (i.e.) per capita consumption is high. More consumption of resources lead to high waste generation – greater is the degradation of the environment. According to Paul Ehrlich and John Hodlren model Overall environmental impact = no. of people x per capita use of resources x waste generated per unit of resources
Environmental Science and Engineering Parameter
MDC
LDC
No. of people
low
High
Per capita consumption of high resources
Low
Waste generated
Low
high
Over all environmental impact of these two types of consumerism may be same or even greater in case of MDC.
Comparison of consumption and waste generation Parameter
Global value % USA
India
Population
4.7
16
Production of goods
21
1
Energy use
25
3
Pollutants and wastes
25
3
CFC Production
22
0.7
Environment (Protection) Act, 1986 CG is to take action to protect and improve environment and SG to co ordinate actions. CG to set up 1. 2. 3. 4. 5. 6.
Std of quality of ]air, water or soil Maximum permissible limits of concentration of pollutants (including noise pollutant) procedures and safe guard for handling hazardous items Prohibition of using hazardous items Prohibition and restriction of certain industries in certain area Procedure and safe guard for prevention of accidents
Environment (Protection) Rules, 1986 SPCB is to follow the guidelines provided in schedule VI. Some are as follows
Environmental Science and Engineering 1. Advises industries for treating the waste water and gases – use of technology – achieve prescribed std. 2. Encourage recycling and reusing the wastes 3. Encourage recovery of biogas, energy and reusable matter 4. Discharge of effluents and emissions into environment is permitted by SPCB after taking into account capacity of the receiving water body 5. To emphasize clean technology to increase fuel efficiency and decrease environmental pollutants The act provides for environmental Audit for checking complying with the environmental laws and regulations. Air (Prevention & Control of Pollution) Act, 1981 Salient features 1. Prevention, control and abatement of air pollution 2. Air pollution has been defined as the presence of any solid, liquid or gaseous substance (including noise) in the atmosphere in such a concentration that may be or tend to be harmful to human being or any other living creature or plants or property or environment. 3. Noise pollution – inserted in 1987 4. CPCB & SPCB similar to water pollution board 5. Section 20 provides for emission std to auto mobile 6. Section 19 provides for SG to declare „air pollution control area‟ in consultation with SPCB 7. Direction of PCB can be appealed in the appellate authority. Water (prevention and control of pollution) Act 1974: Maintaining and restoring the wholesomeness of water by preventing and controlling its pollution. The salient features and provisions of Act are summed as follows. 1. 2. 3. 4. 5.
Maintenance and Restoration of Quality – surface and ground water Establishment of central PCB and state PCB Confers powers and functions to CPCB and SPCB The act provides for funds, budgets, accounts and audits of the CPCB & SPCB The act provides penalties for the defaulters and duties and powers
Wildlife [protection] act, 1972: Land mark in the history of wildlife legislation. 1976 the powers are transferred from state to central government. [I B of W L] was created in 1952 in our country which after WLA, 1972, took up the task of setting National parks and sanctuaries.
Environmental Science and Engineering Wildlife [protection] Act 1 Defines wild life related terminology. 2 Provide appointments of advisory Board, wildlife warden, their powers & duties etc. 3 Prohibition of hunting of endangered species [was first] mentioned. 4 List of endangered species is provided. 5 Guides central 200 authorities. 6 Provides grants for setting up of national parks, wild life sanctuaries etc. 7 The Act imposes ban on trade & commence of scheduled animals. 8 Provides legal proves to officers to punish the offenders. 9 Provide captive breeding programme for endangered species. Many conservation projects for endangered species were started under this act. Lion 1972; Tigers 1973 Crocodile [1974]; Deer 1981. Forest (conservation) Act, 1980 It deals with conservation of forest and includes reserve forest, protected forest and any forest land irrespective of ownership. Salient features 1. State government can use forest only forestry purpose. 2. Provision for conservation of all types of forests. Advisory committee appointed for funding conservation 3. Illegal non-forest activity within a forest area can be immediately stopped under this act. Non forest activity means clearing land for cash-crop agriculture, mining etc. However construction in forest for wild life or forest management is exempted from non forestry activity. 1992 Amendment: 1. This amendment allows transmission lines, seismic surveys, exploration drilling and hydro electric project in forest area without cutting trees or with limited cutting of trees – prior approval CG to be sought.
Environmental Science and Engineering 2. Wild life sanctuaries, National parks etc. are prohibited from exploration except with CG prior approval. 3. Cultivation of coffee, rubber, tea (cash crop), fruit bearing trees, oil yielding trees, trees of medicinal values are also prohibited in reserved forest area with out prior approval from CG. Has this may create imbalance to ecology of the forest. 4. Tusser (a type of silk yielding insect) cultivation in forest area is allowed since it discourages monoculture practices in forests and improves biodiversity. 5. Plantation of mulberry for rearing silk worm is prohibited. 6. Proposal sent to CG for non-forestry activity must have a cost benefit analysis and environmental impact statement (EIS). Environmental Legislation 1972 June 5th – Environment was first discussed as an agenda in UN conference on Human Environment. There after every year 5th June is celebrated as Environment Day. Constitutional Provisions: Added in 1976 – Article 48A – “The state shall endeavor to protect and improve the environment and to safeguard forests and wildlife of the country” Article 51A (g): “It shall be the duty of every citizen of India to protect and improve the natural environment including forests, lakes, rivers and wildlife and to have compassion for living creatures”. By these two articles one constitution makes environment protection and conservation as one of our fundamental duties. Central and state pollution control Board: Central pollution control Board (CPCB): 1. 2. 3. 4. 5. 6. 7. 8.
Advices CG in matters – prevention and control of water pollution Co ordinates SPCB and provide technical assistance and guidance Training programs for prevention and control of pollution by mass media and other ways Publishes statistical and technical details about pollution Prepares manual for treatment and disposal of sewerage and trade effluents Lays std for water quality parameters plans nation-wide programs for prevention, control or abatement of pollution Laboratories for analysis of water, sewage or trade effluents
State pollution control Board (SPCB): SPCB has similar functions as SPCB and governed by CPCB 1. SPCB advises state government w.r.t. location of any industry that might pollute
Environmental Science and Engineering 2. Lays std for effluents to take samples from streams, wells or trade effluents or sewage passing through an industry. Samples taken are analysed at recognized labs. If the sample is not confirming to the water quality std, then the unit is neglected 3. Every industry to obtain consent from PCB before commencing an effluent unit by applying in prescribed form with fee. Enforcement of environmental legislation – major issues 1. 2. 3. 4. 5.
Target of 33% of land to be covered by forest not achieved Rivers turning to open sewers Big towns and cities polluted Wild life endangered EFP (Effluent Treatment Plant) or Air Pollution Control devices are expensive – leads to closure of units. Government should provide subsidy for small units. 6. Pollution control laws not backed up by policy pronouncements or guidelines 7. Chairman of PCB – political nominee. Hence political interference. 8. Involving public in decision making envisaged by policy statement of the ministry of environment and forest (1992) is only in paper. Draw backs of wild life (protection) act Fall out of Stockholm conference not localized Ownership certificate of animals article – illegal trading Trade through J & K. This act not applicable to J&K Offender to get just 3 years imprisonment and or Rs.25000/- fine. Draw backs of the forest (conservation) act 1980
Inheritance of exploitative and consumerist elements of the British period Tribal people (i.e.) inhabitants of forest are left by the act Instead of attracting public support (tribal) it has intrigued in the human rights. Protection of trees, birds and animals have marginalized poor people.
Review Questions 1. Define the term environmental ethics. Environmental ethics refers to the issues, principals and guidelines relating to human interactions with their environment 2. What are the effects of global warming? Increase the sea level Negative effect on crop production and forest growth Decrease the water resource Increase the drought 3. Explain the factors affecting watershed Overgrazing, deforestation, mining, construction activities degrades watershed
Environmental Science and Engineering 4. What is meant by Environmental audit? Environmental audits are indented to quantify environmental performance and environmental position. 5 Write the consequences of ozone layer depletion. Damage genetic materials in the skin cells which cause skin cancer. Affect the aquatic forms Global warming Degradation of paints, plastics 6. What is waste land reclamation? The restoration of disturbed land to ecologically stable condition. To make the land more productive for agriculture 7. What are the state enactments of environmental legislations of India
Smoke control Landuse Pest control Water pollution
Environmental Science and Engineering UNIT 5: HUMAN POULATION AND THE ENVIRONMENT Population growth: Stone age – quite stable Droughts, outbreak of diseases lead to human deaths. 14 th century A.D experienced large scale mortality due to plague – about 50% of people in Asia and Europe died due to the disease. Science and technological advancement has increased the expectancy of human. People started living with good sanitation food and medical facilities increase in population exponentially. In agriculture based families children are said to be assets who help the parents in fields. Therefore, in developing countries the population increase is at a rate of 3.4% per year. Population characteristics and variation among nations: 1. Exponential growth: 1,3,5…… If a quantity varies by a fixed % 10^1, 10^2 etc. 2. Doubling Time Td = 70/r 2% 3. Total Fertility Rate (TFR) is 1.9 developing countries. 4.7 developing countries and 6.1 in 1950 4. Infant mortality: % of infants died out of those born in a year last 50 years. 5. Replacement level: Under low life expectancy and high infant mortality 2.7 in developing countries and 2 in developed countries. 6. Life expectancy: The average no. of years a new born baby is expected to live. The life expectancy of global males and females has risen from 40 to 55.5 years. In India 22.6 and 23.3 in 1900 & 60.3 and 60.5 in 2000. In Japan and Sweden 77-77.4 & 82-84 years. Population explosion: Population explosion means the tremendous increase in the number of people. It is a known fact that the increase of population is playing vital role of all environmental damage. Most of our natural resources are under threat because of the population growth. If the exploitation of resource is going on in this trend, the resources will be exhaust shortly. Population explosion increase disease, economic inequity and environmental abuse. Therefore we need population stabilization to achieve good health, education and prosperity. Reason for population explosion: 1. Increase in birth rate in developed countries due to illiteracy 2. Invention of modern medical facilities reduces mortality rate. Family welfare programme:
Population explosion must be differenced Population is not controlled will deplete all resources Family planning
Environmental Science and Engineering
Allowscouples to describe their family size and also time spacing of their offspring Provide importance, knowledge and benefits of their small family to people Education in held and family welfare system Sex education awareness WHO estimated 50% of worlds married couples adopted family planning measures, 300 million couples not assessed to family planning Environment and human health: Environment is defined as man along with his surroundings, which consists of biotic, abiotic and sociological components. Therefore, when we cause danger to these components, which surrounds us, they in turn affect our health. The environmental dangers created by man are many: Population explosion, unregulated urbanization, creating water, air and landscape pollution, deforestation, desertification, use of pesticides in agriculture etc. Every one of these has implications for the health of the individual as well as society as a whole. None can be ignored because the scale of potential calamity is increasing day by day. Health hazards may be arising from: water contamination or pollution, air pollution, use of pesticides enters through food chain, radiation effect of nuclear water, diseases caused from improper disposal of solid wastes and also due to noise pollution. Human rights: 1. Human rights means that a human being must enjoy on this earth 2. Foundation of human was laid in 13th century. But positive hopes for all people for a happy, dignified and secured living condition wee raised only after “Universal Declaration of Human Rights (UNDHR) by UNO on 1012.1948 3. It highlights on protection to all individuals against injustice and human right violation 4. UNDHR defines specific rights to life, liberty, security, freedom of thought, association, freedom of movement right of equal pay for equal work, right to form or join union, right to health care, education etc. 5. Universal declaration rights are universal but disparity between developing and developed countries. 6. Poverty and population leads to violation of human rights. WHO estimates -One out of every five is malnourished, lacks clean drinking water, lacks hygienic conditions and health facilities. -one out of 3 lack fuel for cooking -1/5 is desperately poor -every year 40 million people die due to contaminated water 7. Acute scarcity of employment
Environmental Science and Engineering 8. Merit of universal education and child labour prevention is of much less importance than his struggle for existence 9. Developed and developing country give importance only to „respect to human rights‟ and „non social – economic rights‟ respectively. Value Education: Education is one of the most important tools in bringing about socioeconomic and cultural progress of a country. The objective of education should not be merely coaching the students to get through the exams with good results and get some good job. Education does not simply mean acquiring information but using the resources within the limits of ethical value. The scientific and technological advancements have shrunk the world into a village. But in the drive to development man has become too materialistic, self centered and over ambitious. Value based education has a very significant role in providing proper direction to youth to inculcate positive attitude and to teach them the distinction between right and wrong. It teaches them to be compassionate, peace loving, helpful, generous and tolerant so that they can move towards more harmonious, peaceful, enjoyable and sustainable future. Value education help in arriving value based judgements based on practical understanding of various natural principles. Value education increases awareness about our national history, our cultural heritage, national pride, constitutional rights and duties, national integration, aommunity development and environment. It is crucial to the retention of national identity, peaceful and harmonious society. Education should give overall development of the student personality. The main of education is to produce citizens with sound character and health. Good citizens are the only hope for the progress and prosperity of the country. Life based upon good principles is an essential requisite. Therefore moral education should be included in the school curriculum. The curriculum should provide enough opportunity for pupils to acquire a considerable amount of knowledge that is essential for morally responsible living in our democratic society. Value education shall prepare individuals for participation in social life and acceptance of social rules. Schools should provide a healthy environment for sharing responsibilities of community life and relationships. Value based environmental education: Environmental education is something that every person should be well versed with. The principles of ecology and fundamentals of environment help to create a sense of earth citizenship and a sense of care for the earth and its resources - a sense of commitment towards the management of the resources in a sustainable way so that our children and grand children too have a safe and clean planet.
Environmental Science and Engineering Following the Supreme Court directives 1998 environmental education has been included in the curriculum right from the school stage to university level. The objective of it is to make everyone environment literate. Let us see how environmental education can be made value based one. 1. Preparation of text books materials on environmental education – to built a positive attitude towards environmental factors. 2. Social values like love, tolerance, compassion can be woven into env. Education. This will help to nurture all forms of life and biodiversity. 3. Cultural and religious values: Our culture and religions teach us not to exploit nature – but to perform such functions which project and sacred nature. Therefore these values can be added up with env. Education. 4. Env. Education should stress on earth centric views rather than human centric view such that it include the ethical values. 5. Global values: Stress on the concept human is part of nature and all natural processes are inter linked and they are in harmony. If this harmony is disturbed it may lead to imbalance in ecology and catastrophic results. 6. Spiritual values: highlights on self contentment, discipline, reduction of wants etc. This will reduce our consumerist approach If the mentioned values are incorporated in env. education, the goal of sustainable development and env. conservation can be easily attained. Value based env. education can bring about a total transformation of our mind set, our attitudes and life style to protect nature. HIV/AIDS AIDS-Acquired Immuno Deficiency Syndrome Acquired means disease is not hereditary but develops after birth from contact with a disease causing agent. Immune deficiency means that the disease is characterized by a weakening of immune system HIV-Human immuno deficiency virus cause AIDS disease.virus is passed through iinfected blood,semen Transmission of AIDS Prostitution Homosexual activity Use of contaminated syringe in blood transfusion and drug addicts Maternal-fetal transmission Symptoms:
Persistent fever Fatique, weekness Diarrhea Wait loss Low number of T cells in blood Swelling lymph nodes, neck
Environmental Science and Engineering Susceptible to infections Treatment: AZT-Azidi thymidine DDI – Dideoxyinosine Screening test: ELISA-Enzyme Linked Immuno Sorbant Assay Western blot Polymer chain reaction Saliva and urine test Branched DNA test Immuno fluorescent antibody assay The major precautions to avoid AIDS
education prevention of blood borne HIV transmission primary health care counseling services drug treatment
Role Of Information Technology In Environment And Human Health: Computer based instruments for environment studies: There are several on-line use instruments by which data can be collected automatically at fixed interval of time. Eg. 1. Instruments for monitoring and analysis of meteorological parameters, the acoustic sounding system, radar is used 2. Atomic absorption spectrophotometer (AAS) – performs complex chemical and heavy metal analysis in water and waste water. 3. Inductive coupled plasma spectrometer (ICPS), attached with powerful computers to facilitate easy manipulations, is used for waste water analysis. Application of computers in the field of Environment & human health: 2. Unknown parameters can be stimulated by computer techniques 3. EIA(Environmental Impact Assessment) problems can be analyzed 4. Inventories of emission sources are compiled and maintained 5. Net-work analysis, statistical analysis and the status of environmental pollutions can be high lighted 6. Comprehensive administrative system can be developed by using computer network techniques.
Environmental Science and Engineering Remote sensing-Graphical Interface System are useful for coral reef mapping and ocean resources. They are also useful to access the loss of biodiversity/hot spots etc. Review questions: 1. What do you mean by carrying capacity of population? The maximum popu;lation size that an ecosystem can support under particular environmental condition 2. What are the reasons for population explosion? Improved sanitary conditions Better heath care increase in productivity of agriculture and industry 3. What are the factors influencing human population Unwanted fertility To increase the income for family and support Lack of knowledge on population control methods 4. What is silicosis and asbestosis? Silicosis is caused due t contamination of free silica Asbestosis is due to asbestos fibres deposited in lungs 5. List any four vector borne disease Malaria Dengue Filaria Encephalitis 6. What is ameobiasis?Give its source. 7. This is a water borne disease, caused by amoeba i.e., Entameoba histolytica and charecterised by liquid stools with mucous and blood Source; food chain-fruits, vegetables, contaminated drinking water, cold drink 8. What are the two primary strains of HIV HIV-1 Strain HIV -2 strain
Environmental Science and Engineering 9. List any two drugs used in treatment of AIDS AZT-Azidothymidine DDi-Dideoxyinosine 10. List any two applications of information technology in environment Data on environmental degradation will help to restore the conditions Geographic information system by application of information techniology will help in environmental conservation FIVE YEARS ANNA UNIVERSITY EXAM QUESTION AND ANSWERS UNIT 1: ENVIRONMENT, ECOSYSTEM AND BIODIVERSITY 1. Differentiate between a biome and an ecosystem On earth there are many sets of ecosystems which are exposed to same climatic conditions and having dominant species with similar lifecycle,Climatic adaptations and physical structure. This set of Ecosystem is called Biome (Small ecosystem) A group of Organisms Interacting among themselves and with environment is known as ecosystem.- is the basic functional unit of Ecology. 2. Define: Food chain and Food Web In linear food chains, if one species gets affected or becomes extinct, then the species in the subsequent tropic levels are also affected. Net work of food chain – Food web – if one species gets affected, it does not affect other tropic levels so seriously. 3. Differentiate between genetic diversity and species diversity Genetic diversity – diversity within species ie., variations of genes within the species. Species diversity - diversity between different species. The sum of varieties of all the living organisms at the species level is known as species diversity. 4. Define the terms producers and consumers Producers – depend on their food themselves through Photosynthesis. Eg. All green plants , trees. Consumers. - depend directly or indirectly on the producers eg. Plant eating species, animals eating species. 5. What are ecological pyramids?
Environmental Science and Engineering Graphical representation of structural and function of tropic levels of an ecosystem is called ecological pyramids. 6. Define “Hot spots of biodiversity” The hot spots are the geographic areas which possess high endemic species. 7. Define biodiversity. Biodiversity – the variety and variability among all groups of living organisms and the ecosystem in which they occur. 8. Define ecology. Ecology – study of interactions among organisms or group of organisms with their environment (Biotic and Abiotic Organisms) 9. What is ecological succession? The progressive replacement of one community by another till the development of stable community in a particular area is called ecological succession. UNIT 2:ENVIRONMENTAL POLLUTION 1.
What is marine pollution? Marine pollution is defined as the discharge of waste substances in to the resulting in harm to living resource, hazards to human health, hindrance to fishery and impairment of quality for use of sea water. 2. Define a) Decibel b) COD a) Decibel:-Decibel (dB) is defined as the one tenth of the longest unit Bel. b) COD:-COD (Chemical Oxygen Demand) is the amount oxygen required for chemical oxidation of organic matter using some oxidizing agent like K2Cr2O7 and KMnO4. 3. What are the effects of noise pollution?
Interferes with man‟s communication
Hearing damage
Physiological and psychological changes
4. How solid wastes are disposed ultimately? Landfill,incineration,composting 5. What are the causes of water pollution?
Domestic sewage Industrial effluents
Environmental Science and Engineering
Synthetic detergents Agro chemicals Oil Thermal pollutants Run off from land fills
6. What is disaster? Give few examples Disaster is a geological processes and is defined as the sudden calamity which brings misfortune and miseries to human community e.g., flood, cyclone, landslide, earthquake and Tsunami 7. Differentiate between pollution prevention and pollution control
Pollution prevention
Pollution control
It means using processes, practices, materials, products or energy that avoid or minimize the creation of pollutants and waste or environmental disturbances and reduse risk to human health
The proper control measures practiced to minimize the pollution level.
8. Differentiate between primary and secondary air pollutants with examples:
Primary pollutants
Secondary pollutants
These are emitted directly in the These are pollutants in which atmosphere in harmful form some of the primary air pollutants may react with one Examples:CO,NO,SO2 another to form new pollutants Examples: NO,NO2------HNO3/NO3
Environmental Science and Engineering 9. Give any six air pollutants Sulphur dioxide Nitrogen oxides Sulphur trioxide Carbon dioxide Hydrocarbons Carbon monoxide
UNIT:3 NATURAL RESOURCES 1. Distinguish renewable and non-renewable sources of energy Energy renewable
Advantage
Energy non renewable
Disadvantage
Wide availability Unreliable supply Low cost Produced in small Decentralized power quantity production Difficult to store Low pollution Cost more Available for the future Available in high highly pollution concentrated form Available only in few places Easy to store Reliable supply High running cost Lower cost Limited supply and will one day get exhausted
2. What is sustainable development? Sustainable development is defined as meeting the needs of the present without compromising the ability of future generations to meet their own needs, or extending progress, without exhausting resources, beyond the foreseeable future. 3. Write any two adverse effects caused by overgrazing. Land degradation
Loss of useful species.
4. What is desertification? Give any two reasons for it. Desertification means degradation of one fertile land to desert like land. Reason-deforestation, overgrazing,mining,overgrazing 5. What are the reasons for deforestation?
Environmental Science and Engineering Deforestation means increasing agricultural production, increasing industrial activity, increasing demands for wood resources 6. Define Land Degradation. Land degradation means process of deterioration of soil or loss of fertility of soil. 7. What is an aquifer? A highly permeable layer of sediment or rock containing water 8. What does strategic metals and minerals mean? These are the metals and minerals that a country uses but cannot produce itself. essential for defence. e.g., cobalt,iron,manganese 9. What is water logging and how it is prevented? Saturation of soil with irrigation water or excessive precipitation so that the water table rises close to surface.
Prevent excessive irrigation
Subsurface drainage and bio drainage by trees like Eucalyptus trees are adopted
Leakage from water pump are detected
10. Write any two effects of ground water depletion. lower the surface water level Land subsidence Salt water intrusion Climate change 11. List any four adverse affects of mining. Scarring and disruption of land surface Land subsidence Smelting causes air pollution Acid mine drainage contaminates ground water
UNIT 4:SOCIAL ISSUES AND THE ENVIRONMENT 1. Define watershed management. The management of rainfall and resultant run off is called watershed management 2. What is green house effect? Green house effect may be defined as the progressive warming up of the earth‟s surface due to blanketing effect of man made carbondioxide in the atmosphere 3. What are the advantages of rainwater harvesting? Reduction in the use of current for pumping water Mitigation by effects of droughts and achieving drought proofing
Environmental Science and Engineering
Increasing the availability of water from well Rise in ground water level Minimizing the soil erosion and flood hazards
4. What is acid rain? The presence of excessive acids in rain water is acid rain. 5. What are the effects of acid rain? Acid rain corrodes houses, monuments, statues, bridges and fences. Deteriorate the paint and stone 6. What are the objectives of watershed management? To minimize the risk of foods, droughts and landslides To develop rural areas in the region with clear plan for improving the economy To generate huge employment opportunities To protect the soil from erosion by run off To rise ground water level UNIT 5 : HUMAN POPULATION AND THE ENVIRONMENT 2. Differentiate between HIV and AIDS. HIV-Human innuno deficiency virus cause AIDS disease.virus is passed through iinfected blood,semen. AIDS-Acquired Immuno Deficiency Syndrome Acquired means disease is not hereditary but develops after birth from contact with a disease causing agent. Immune deficiency means that the disease is characterized by a weakening of immune system 3. What are the major precautions to avoid AIDS? education prevention of blood borne HIV transmission primary health care counseling services drug treatment 4. Define “Human rights”. Human rights are the fundamental rights, which are possessed by all human being irrespective of their caste, nationality, sex and language. 5. What is population explosion? The enormous increase in population due to low death rate (mortalityt) and high birth rate (natality), is termed as population explosion. 6. Write any two applications of information technology in environment. Land and water management Information on type, density, biomass, forest fire, pest and disease.
Environmental Science and Engineering
7. What are the reasons responsible for population explosion? Invention of modern medical facilities reduces the death rate and increases the birth rate. Increase of life expectancy Illiteracy 8. Write the value of education to the society. Improve the integral growth of human being create attitude and improvement towards sustainable lifestyle to understand about natural environment. 9. What are the major objectives of family welfare programme in India? reduce infant mortality rate to below 30/100 infants achieves 100% registration of birth, death and marriage encourage late marriage and later child birth constrain the spread of AIDS/HIV
