ENVIRONMENTAL SCIENCE AND ENGINEERING ENGINEERING – GE2021 LESSON NOTES UNIT 1
DEFINITION, SCOPE AND IMPORTANCE Environmental science is the study 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”. Env. 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 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 popu lation has resulted in 1) depletion of various resources of earth 2) pollution. Principles of env. education: 1. 2. 3. 4. 5.
Examine the major env. issues discover the root cause develop problem solving skills Promote co-operation in solving solving problems Emphasis active participation participation in prevention and solution to problems.
Scope of env. science: 1. Studying the interrelationship interrelationship between the components of env. 2. Carrying out impact analysis and env. Audit 3. Preventing pollution from existing and new industries 4. Stopping the use of biological and nuclear weapons 5.. Managing unpredictable disasters etc. PUBLIC AWARENESS: Env. Pollution or problems cannot be solved by mere laws. Public participation is an important important aspect which serves the env. Protection. / Public awareness of env. Is at infant stage / 30-40% of public of developing country are aware of env. Problems but they do not bother about it. / Ignorance and incomplete knowledge has lead to misconceptions /development and improvement in std. of living has lead to serious env. Disasters /debate on env. Issues are treated as anti-developmental Reasons for env. Ignorance: 1. Science, technology and economics failed to integrate the knowledge on env. Aspects in curriculum 2. The decision makers do not process env. Angle of decision decision making 3. Consideration of economic growth, poverty eradication eradication has lead to env. Degradation 4. Only few developmental activities activities are made made considering the env. 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 acti action. on. Publ Public ic parti partici cipat patio ion n is poss possib ible le only only when when the the publ public ic is awar awaree about about the ecol ecolog ogic ical al and environmental issues. Eg. Ban- the littering littering of polythene. Methods to propagate env. Awareness: 1. Among students through education – introducing introducing environmental studies in the curriculum. curriculum. 2. Among public through mass media- environmental environmental programmmes through TV, radio radio etc. 3. Among decision makers, planners, leaders etc. Role of NGOs 1. Advise the government in in interacting with with ground level people 2. Organize public meetings 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 resources-conservation and management 2. Ecology and biodiversity – conservation 3. Env. Pollution Pollution and prevention 4. Social issues related to development and environment 5. Human population population and env. ENVIRONMENTAL RESOURCES Any component of the env. Which has intrinsic intrinsic value of its own is called as resource. 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 Continuous Eg. Clean air, clean water Ground water, minerals Solar energy, energy Considered to be Avai Availa lable ble only only in fini finite te Considered to renewable with quan quanti tity ty – thei theirr rate rate of available always. considerabl considerablee life span-as span-as renew renewal al is so slow slow that that long as they have the they they are are cons consid ider ered ed as capacity to renew – non-renewable unless unless they they are affect affected ed by catastrophes or anthrophogenic activity.
Extrinsic wind Human skills be
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 acti action. on. Publ Public ic parti partici cipat patio ion n is poss possib ible le only only when when the the publ public ic is awar awaree about about the ecol ecolog ogic ical al and environmental issues. Eg. Ban- the littering littering of polythene. Methods to propagate env. Awareness: 1. Among students through education – introducing introducing environmental studies in the curriculum. curriculum. 2. Among public through mass media- environmental environmental programmmes through TV, radio radio etc. 3. Among decision makers, planners, leaders etc. Role of NGOs 1. Advise the government in in interacting with with ground level people 2. Organize public meetings 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 resources-conservation and management 2. Ecology and biodiversity – conservation 3. Env. Pollution Pollution and prevention 4. Social issues related to development and environment 5. Human population population and env. ENVIRONMENTAL RESOURCES Any component of the env. Which has intrinsic intrinsic value of its own is called as resource. 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 Continuous Eg. Clean air, clean water Ground water, minerals Solar energy, energy Considered to be Avai Availa lable ble only only in fini finite te Considered to renewable with quan quanti tity ty – thei theirr rate rate of available always. considerabl considerablee life span-as span-as renew renewal al is so slow slow that that long as they have the they they are are cons consid ider ered ed as capacity to renew – non-renewable unless unless they they are affect affected ed by catastrophes or anthrophogenic activity.
Extrinsic wind Human skills be
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 surface of the earth. rd th Around 1/3 of world land land area was found found to be forests. forests. 1/5 of world forests were found in Brazil and 6-7% was in Canada and USA. But the matter under high concern is 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. Production Production of Oxygen: Photosynthes Photosynthesis is – earth’s earth’s lungs lungs 2. Reduci Reducing ng global global warmi warming ng – sink sink for carbo carbon n di oxide oxide 3. Wild life life habitat habitat – 7 milli million on species species in tropica tropicall forests forests alone alone 4. Regulation Regulation of hydrologic hydrological al cycle – prevent prevent surface surface run off – giant sponges sponges – 50-80% 50-80% moisture moisture 5. Soil conservat conservation ion – hold solid solid particl particles es tightly tightly and prevent prevent soil soil erosion erosion – wind breaks breaks 6. Pollution Pollution moderato moderators: rs: absorb absorb toxic toxic gases and purify purify air air reduce reduce noise polluti pollution on
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. Excess Excessive ive use of charcoal charcoal,, fuel fuel wood, wood, expans expansion ion of urban, urban, agricu agricultu ltural ral and indust industria riall areas 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 intemperate countries are relatively moderate. But it is alarming 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 declaration per year between 1982 - 90. During this period it is is estimated estimated that about 1.44 mha land was brought brought under afforestat afforestation. ion. 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 forests(satellite data). data). MAJOR CAUSES OF DEFORESTATION: 1. Shifting Shifting of Cultivati Cultivation on – 300 million million people – 5 lakh hectares hectares of forest forest for slash slash and burn culture culture 2. fuel fuel requ requir irem emen entt 3. raw materi materials als for indust industria riall use use 4. devel developm opment ental al pro proje ject ctss 5. grow growin ing g foo food d nee needs ds 6. over overgr graz aziing CONSEQUENCES OF DEFORESTATION 1. threatens threatens many many wild life specie speciess due to destru destruction ction of of natural natural habitat habitat 2. biodiversi biodiversity ty is lost along with that geneti geneticc diversity diversity 3. hilly hilly regio regions ns are are made made prone prone to land landsli slides des
4. soil erosion and loss of soil fertility 5. hydrological cycle is affected (loss of rainfall, flood, drought etc) 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. Displacement of tribal people 2. Loss of flora and fauna 3. siltation and sedimentation near reservoir 4. stagnation and water logging near reservoir 5. growth of aquatic weeds 6. micro climatic changes 7. RIS causes earthquakes 8. breeding of disease vectors Downstream problems 1. Water logging and salinity due to over irrigation 2. micro climatic changes 3. salt water intrusion at river mouth 4. loss of fertility due to sediment deposits 5. Out break of vector born diseases. 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. Sustainable forest Management Sustainable forest management (SFM) is the use of the world’s forest in such a way that they continue to provide resources in the present, without depriving future generations of their use. One of the principles of SFM is to fully involve local communities in forest management. Implementing this principle is difficult since forest departments are usually very reluctant to lose their control over forest resources. SFM has also become an element of climate change negotiations. As mentioned earlier, the Kyoto Protocol would compensate countries for the benefits their forests provide to the world. The industrialized countries are ready to support SFM in developing countries so that they can buy the credits and continue to pollute the atm. By 2000, 149 countries were engaged in nine international initiatives to develop and implement criteria and identify indicators for SFM, covering 85 per cent of the world’s forests. There are 140 countries with national programmes I in various stages of development. Certification of forest as coming from sustainable forests is another approach Certification is a voluntary market-based approach that enables us to identify forest products backed by high environmental standards. It focuses on the quality of forest management rather than on that of forest products. Three certification methods are in operation: 1. Accreditation by the Mexico-based Forest Stewardship Council (FSC) 2. ISO 14000 Environmental Management System (EMS) similar to ISO 9000 certification 3. Pan-Europe Certification Scheme and national certification schemes by individual countries.
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. •
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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 spoil 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.
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 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. Dams and reservoirs can be constructed 2. Embankments and proper channel management 3. Flood way should not be encroached 4. Forecasting or flood warning 5. Decrease of run off by infiltration through afforestation or rain water harvesting etc. Overgrazing: Grass is a good binder of soil. Overgrazing leads to loss of vegetal cover. Soil gets compacted because of excess evaporation of water. Water cannot percolate into the soil. Roots cannot pass into the soil. Soil texture is lost, fertility is lost and at last leads to soil erosion. Soil erosion: when uncovered, waterless soil is acted upon by heavy wind and rainfall soil erosion results. This leads to loss of useful species and many nutrients. Overgrazing leads to replacement of thorny plants in the place of leafy, fruit bearing plants.
HYV: The usage of high yield crop variety leads to monoculture – same type of crop is planted on large scale. In case of any pathogenic effects, due to exactly uniform condition in the crop field, total loss is encountered. Food resources: PROBLEMS FACED BY FOOD RESOURCES
Overgrazing
Land degradation Soil erosion Loss of useful species
modern agriculture
high yield variety crops micronutrients imbalance nitrate pollution Eutrophication Pesticide related problems Water logging Salinity
Micronutrient imbalance: excessive use of macronutrients causes micronutrients imbalance. deficiency faced in Punjab and Haryana.
Ex. Zinc
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. 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. engg. Constructions Soil Conservation: Ways to reduce 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. 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.
UNIT II
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. ENERGY FLOW IN ECOSYSTEM: Energy is defined as the capacity ot 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
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 (Plants)
Consumer I order (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. Grass
Mouse Rabbit Grasshopper
snake Hawk
Lizard
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
MAJOR TYPES OF ECOSYSTEMS 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
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.
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. 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
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
Energy flow: Grass
worms
Insects
small birds huge birds
Decomposition
sediments
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. 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 be autiful. 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.
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The concept of biodiversity may be analyzed in 3 different levels. They are 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. 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
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medicinal plants) •
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• •
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.
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 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. long term captive breeding 2. shortage term propagation and release 3. animal translocation and re introductions 4. seed bank 5. reproductive technology (i) embryo transfer technology (ii) cloning Biodiversity and National Environmental law: All environmental problems are regional in nature but their effects are global. Hence environmental problems cane be resolved only by extensive co operation among nations. Laws serve to achieve global objective of environmental protection. Indian law for conservation of biodiversity: The wild species of the group and other related species constitute a rich gene pool in India. The government of India has enacted laws for the conservation of biological diversity. The habitat protection laws: This includes species protection laws and habitat protection laws which indirectly protect and conserve the biological diversity and its components. The wild life (protection) Act 1972: Enacted 1. to protect wild animals and birds which are in the verge of extinction 2. to protect biological diversity in particular and environmental protection in general. 3. for the protection of wild animals and birds and for all other matters connected there of or ancillary and incidental there to. Biosphere Reserve and the wild life (protection) Act 1972: Biosphere reserves are complementary to the existing network of national parks and sanctuaries, this act is enacted to protect biosphere.
UNIT III POLLUTION Marine Pollution Dumping of waste and oil spillage in the oceans or seas, which create threats to marine ecosystem, is called marine pollution. Sources: 1. waste disposal 2. oil spill 3. thermal pollution (plants located nearby coastal areas) 4. ship breaking activities 5. aquaculture practices 6. nuclear test conducted in seas and oceans Effects:
disturb entire aquatic or marine ecosystem oil has suffocation effect on most aquatic animals 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
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. Area
Industrial Commercial Residential Silent Zone Sounds and their decibel scale: 1. Rocket engine – 180 dB 2. Jet plane take off – 150 dB
Permissible noise level(dB) Day Night 75 70 65 55 55 45 50 40
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 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.
AIR POLLUTION: It is an atm. 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
Sources of air pollution
Natural sources 1. Volcanic eruption 2. Forest fires 3. Biological decay
4. Sea salt spray 5. Pollen grains of flowers
man made sources(anthropogenic) 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) 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 pollutants (CO2, NOX) (dust, mist)
particulate air pollutants
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. 1
Pollutant Aldehydes
2
Ammonia
3
Arsenic
4
Carbon Monoxide
5 6
Cadmium Chlorine
7
Hydrocarbons
8
Hydrogen Sulfide
9
Nitrogen oxides
10
Ozone
11
Sulphur dioxide
12
Suspended solids
Sources Thermal decomposition of fats and oils Chemical processes, dye making, explosives and fertilizers Coal and oil furnaces
Motor exhausts, oil and coal furnaces oil and coal furnaces Chemical industries Unburnt gasoline vapours Sewage treatment, refineries Motor vehicle exhaust Photochemical reactions Coal and oil combustion Industrial manufactures
Control of air pollution: 1. Using non conventional energy 2. Using bio filters 3. Planting more trees 4. Reducing vehicle exhausts 5. Using less polluting fuels
Effects on human Irritates nasal and respiratory tracts
Upper respiratory passage
Damages kidney, cause jaundice, lung and skin cancer damages lungs and heart Damages kidney Attacks respiratory tracks, mucous membranes Fog formed with combination of NOx affects respiratory system Irritates eyes, causes nausea, bad odour Bronchitis Eye irritation, aggressive asthma Obstructs breathing, irritates eyes Eye irritation, asthma, air suffocation, lung cancer
6. 7. 8. 9.
Using mass transport Removal of particulate matter using electrostatic precipitator, cyclone filter etc. Setting of industries of EIA Removal of NOX from vehicle exhaust
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: 1. Increase evaporation of surface water – influence climate change 2. Leads to declining biodiversity 3. Melting of mountain glaciers and polar ice, which cause rise in sea level 4. Change the climate and rainfall – reduction in food production 5. The biological productivity of ocean also decreased due to warming of earth’s surface 6. 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 atm. with in next 50 years, and will makes the average global temp. to 450 C.
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 atm. 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. Marked rise in cause skin cancer 2. Damage immune system 3. Eye ailment such as cataract 4. Shorter life of paints and plastics 5. Restricted growth and crop damage 6. Destruction of aquatic life 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.
Cause: 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. suspended matter 2. thermal discharge 3. pathogens (bacteria, fungi, protozoa fungi) 4. natural organic pollutants 5. synthetic organic pollutants 6. inorganic chemicals 7. radioactive waste, oil, sediments 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 measure 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 • • • •
• • • •
UNIT IV
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 Parameter MDC No. of people low Per capita consumption of high resources Waste generated high
LDC High Low Low
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 %
Population Production of goods Energy use Pollutants and wastes CFC Production
USA 4.7 21 25 25 22
India 16 1 3 3 0.7
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. 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. 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. 4. 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 – p rior approval CG to be sought. 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). 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. Maintenance and Restoration of Quality – surface and ground water 2. Establishment of central PCB and state PCB 3. Confers powers and functions to CPCB and SPCB 4. The act provides for funds, budgets, accounts and audits of the CPCB & SPCB 5. The act provides penalties for the defaulters and duties and powers CPCB: 1. Advices CG in matters – prevention and control of water pollution 2. Co ordinates SPCB and provide technical assistance and guidance 3. Training programs for prevention and control of pollution by mass media and other ways 4. Publishes statistical and technical details about pollution 5. Prepares manual for treatment and disposal of sewerage and trade effluents 6. Lays std for water quality parameters 7. plans nation-wide programs for prevention, control or abatement of pollution 8. Laboratories for analysis of water, sewage or trade effluents 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 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.
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. 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. Std of quality of ]air, water or soil 2. Maximum permissible limits of concentration of pollutants (including noise pollutant) 3. procedures and safe guard for handling hazardous items 4. Prohibition of using hazardous items 5. Prohibition and restriction of certain industries in certain area 6. 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 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. 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.
UNIT V POPULATION GROWTH
Reasons for the exponential growth: Stone age – quite stable Droughts, outbreak of diseases lead to human deaths. 14th 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. 2. 3. 4. 5.
Exponential growth: 1,3,5…… If a quantity varies by a fixed % 10^1, 10^2 etc. Doubling Time Td = 70/r 2% Total Fertility Rate (TFR) is 1.9 developing countries. 4.7 developing countries and 6.1 in 1950 Infant mortality: % of infants died out of those born in a year last 50 years. 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.
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 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. 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. 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 ecofriendly development. (Eg) 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.
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 judgments 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, community 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. 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.
