CBSE CLASS 10 CHAPTER 16 NOTES

 

CHAPTER 16

CBSE SCIENCE
CLASS 10

CHAPTER 16

MANAGEMENT OF NATURAL RESOURCES

 

CONTAMINATION OF GANGA

·        Coliform – a gram negative rod shaped bacteria – found in human intestine

·        Their presence in water – indicator of contamination by disease causing micro organism – indicating faecal pollution

·        It includes Salmonella & Escherichia coli

·        Largely untreated sewage – garbage & excreta are dumped into Ganga

·        Pollution is also caused by – human, washing & immersion of ashes or unburnt corpses

·        Industries – also contribute to Ganga’s pollution – loading chemical effluent – making the water toxic, killing aquatic organisms

 

GANGA ACTION PLAN

·        Ganga action plan – massive multicrore project – launched in 1985 – undertaken to clean the excess pollution from river Ganga

 

SUSTAINABLE DEVELOPMENT

·        Sustainable development – development which can be maintained for a long time – without damaging the environment

·        Objective – to provide the economic well being to present & the future generation - & to maintain a healthy environment & life support system

 

POLLUTANTS & THE WAY TO FIND ITS PRESENCE

·        pH – Potential of Hydrogen

·        Acidic & basic characters of aqueous solution – described in terms of hydrogen & hydroxyl ion concentration

·        Pollutants – substances that causes harmful change in the environment – producing adverse effect on living organisms

·        Examples of common pollutants – industrial wastes, emission of fumes from vehicles, sewage, pesticides

 

FIVE R’s TO SAVE THE ENVIRONMENT

REFUSE

·        ‘Say No’ to things you don’t need

·        Refuse to buy products that harm you & the environment

·        Say no to single use plastic bags

 

REDUCE

·        Reduce means to ‘use less’

·        By switching off unnecessary lights, fans to save electricity

·        By repairing leaking taps to save water

·        By not wasting food

 

REUSE

·        Reuse means ‘to use things again & again’

·        Used envelopes can be reversed & used again – instead of throwing away

·        Plastic bottles of food items – such as jam or pickle – can be used for storing things in the kitchen

 

REPURPOSE

·        Repurposed means when a product can no more be used for the original purpose

·        Use it for some other useful purpose

·        Example: cracked crockery, or cups with broken handle – used to grow small plants or as feeding vessels for birds

 

RECYCLE

·         Recycle means to collect plastics, paper, glass & metal items – recycle these materials to make required things

·        We need not extract fresh plastic or paper

·        In order to recycle – first segregation of waste is necessary – so that materials which can be recycled are not dumped along with other wastes

 

REUSE BETTER THAN RECYCLE

·        Reuse is better than recycle – because the process of recycling – uses energy

·        Reuse – you can simply use things again & again without using energy for generating something

 

THE NEED TO MANAGE NATURAL RESOURCES

·        A majority of natural resources – limited

·         Human population – increasing at a tremendous rate

·        Utilization of natural resources – also increasing

·        Need to conserve the resources for future generation

 

ENVIRONMENTAL POLLUTION CAUSED DUE TO MINING

·        Mining – causes pollution – large amount of slag is discarded – for every tonne of metal extra red

 

FOREST & WILDLIFE

·        Biodiversity – existence of wide variety of species of plants, animals & micro organisms in the natural habitat within a particular environment

·        Forests – biodiversity hotspots – is an area where number of species exists

·        Wildlife – naturally occurring animals & plants – which are not cultivated, domesticated or tamed

·        Conservation – sensible use of the Earth’s natural resources – to avoid excessive degradation & betterment of the environment

·        Afforestation – practice of transforming an area into forests – usually when trees have not grown there

 

TYPES OF FORESTRY PROGRAMME

SOCIAL & ENVIRONMENTAL FOREST

·        Raising of trees for firewood & fodders – for the benefit of rural & tribal community

AGRO FORESTRY

·        Commercial forestry – developed to fulfil the need of various forest based industries

URBAN FORESTRY

·        It involves growing of ornamental trees along roads, vacant lands & common parts of urban areas

 

FOUR STAKE HOLDERS OF FOREST

·        The people living in or around the forest – directly dependent on forest products

·        Forest department – of the Government – which owns the land & controls the resources from forests

·        Industrialist – who use forest produce – but not dependent on forests of a particular area

·        Wildlife & nature enthusiasts – who wants to conserve it

 

PROBLEMS FACED BY PLANTING SINGLE VARIETY OF PLANTS OVER A VAST AREA

·        Loss of Biodiversity

·        Varied needs of the local people can no longer be met

·        Degradation of soil

 

LOCAL PEOPLE WORKING TRADITIONALLY FOR CONSERVATION OF FORESTS

·        Bishnoi Community – Western Rajasthan – border of Thar desert

·        The people sacrifice their own lives to conserve forest & wildlife & to protect the environment

·        Their basic philosophy – all living things have a right to survive & share all resources

·        Government of India – recently instituted Amrita Devi Bishnoi National Award – Wildlife conservation

·        In memory of Amrita Devi Bishnoi (1731) – sacrificed her life along with 363 others – protection of Khejri trees in Khejri village near Jodhpur in Rajasthan

 

HIMALAYAN ALPINE MEDOWS

·        The Great Himalayan National park – contains alpine meadows – graded by sheep in summer

·        Nomadic shepherds – drove their flock here every summer

·        When the National Park was formed – this practice was put to an end

·        Without grazing – grass first grows tall & falls over – preventing fresh growth

 

MANAGEMENT OF FOREST

·        Forest resources – available for industrial use at low rate – while they are denied to local people

·        Chipko Andolan (Hug the trees Movement) – to end the alienation of people from their forests

·        Chipko Movement – started in early 1970s – in a village called Remi in Gharwal high up in the Himalayas

·        The women of the village hugged the trunks of trees and thereby prevented from cutting the trees

·        This incident spread throughout the country which made the Government to rethink their priorities in the use of forest produce

 

AN INDIVIDUAL’S CONTRIBUTION IN THE MANAGEMENT OF FOREST & WILDLIFE

·        Avoid cutting of forest & killing of wildlife

·        Educating people – about the importance of forests & wildlife in our life

 

MEASURES TAKEN TO CONSERVE FOREST

·        Deforestation should be banned

·        Forest resources should be used – in environmentally & developmentally sound manner

·        Should use natural resources cautiously

·        Afforestation – should be done

 

WHAT DAMAGE IS CAUSED TO THE FOREST BY THE FOLLOWING

Building rest houses for tourist in National Park

·        Disturbance in natural habitat

·        Waste disposal

·        Restriction in movement of animals

·        Poaching/ hunting

Growing domestic animals in National Park

·        Ecological imbalance

·        Loss of food for herbivores

·        Overgrazing

·        Might result in loss of habitat

 

ADVANTAGES OF CONSERVING FOREST &WILDLIFE

FOREST

·        It helps in retaining the subsoil water

·        It helps to check flood

WILDLIFE

·        To maintain ecological equilibrium

·        To protect the nature

 

WATER FOR ALL

·        Water – basic necessity for all terrestrial forms of life

·        Rains in India – largely due to monsoons

·        Failure to sustain water availability – results in loss of vegetation cover

·        Irrigation methods – dams, tanks & canals – used in various parts of India – from ancient times

·        These were managed by local people – this assures the minimum requirements for both agriculture & daily needs were met

·        Arrival of the British – changes these systems

·        Large scale projects – large dams & canals traversing large distances – implemented by the British

·        This was carried on by our newly formed Independent Government

·        Mega projects – led to neglect of local irrigation – & Government took over the administration of local systems – lead to loss of control over local water sources by the local people

 

DAMS

·        Large dams – ensure storage of water – for irrigation & generation of electricity

·        Canal system – transfer large amounts of water over great distances

 

PROBLEMS FACED WHILE RAISING DAMS

·        SOCIAL PROBLEMS Large number of people (peasants & tribals) – displaced without adequate compensation or rehabilitation

·        ECONOMIC PROBLEMS as large amount of public money is used up – without generation of proportionate benefits

·        ENVIRONMENTAL PROBLEMS They contribute to deforestation & loss of biodiversity

 

WATER HARVESTING

·        Water – saving methods – dug small pits, lakes, built small earthern dams, dykes, sand & limestone reservoirs, roof top water collecting units

·        Water harvesting systems in India.

·        RAJASTHAN – Khadins, tanks & nadis

·        MAHARASHTRA – Bandara & tals

·        MADHYA PRADESH & UTTAR PRADESH – Bundhis

·        BIHAR – What’s & pynes

·        HIMACHAL PRADESH – Kulhs

·        JAMMU (KANDI BELT) – Ponds

·        TAMIL NADU – Eris (tanks)

·        KERALA – Surangams

·        KARNATAKA - Kattas

 

TRADITIONAL WATER HARVESTING SYSTEM

·        Large level terrain – crescent shaped earthern embankments or check dams

·        Monsoon rains – fills Ponds behind the structures

·        Main purpose – to recharge ground water

ADVANTAGES OF GROUND WATER

·        It does not evaporate

·        Spreads out to recharge wells

·        Provide moisture – vegetation over a large area

·        Does not provide breeding ground for mosquitoes

·        Remain protected – from contamination – human & animal waste

 

COAL & PETROLEUM

·        Large reservoirs of petroleum – preserved by nature – over millions of years – between porous rocks – beneath the Earth

·        Non-renewable energy resources – cannot be replaced easily – when They get exhausted – also called conventional source of energy

·        They are used traditionally for many years – take millions of years to form fossil fuels

·        Fossil fuels (Coal & Petroleum) – get exhausted & their combustion pollutes our environment- judicious use of these resources is necessary

·        When combustion takes place – oxides of carbon, hydrogen, nitrogen & sulphur are formed

·        Carbon monoxide is formed instead of carbon dioxide – if there is insufficient air (O2) – due to which partial combustion takes place

·        The oxides of sulphur, nitrogen & carbon monoxide – poisonous at high concentration

·        Carbon di oxide – green house has – leads to global warming

 

CHARACTERISTICS OF A GOOD FUEL

·        High calorific value

·        Lesser pollution

·        Sustainable for a long period

·        Easily transportable

 

NEED FOR ALTERNATE ENERGY

·        Fossil fuels – conventional source of energy – will not last longer

·        To reduce air pollution

·        Alternate energy – wind mills, hydro electricity, biogas, solar energy

 

ACTIVITIES THAT REDUCE CONSUMPTION OF NATURAL RESOURCES

·        Switching off unnecessary light & fans to save electricity

·        Using LED bulbs in homes

·        Repairing leaky taps to save water

·        Not to dump the materials that can be recycled, like paper

·        Taking a bus, using bicycle or go by walk for short distance

·        Take the stairs instead of the lift

·        Wear an extra sweater instead of using a heating device