Unit 6: Social Issues and the Environment (Classes: 10; Marks: 15)
[Environmental Studies Notes for BCOM/BA/BSC 2nd SEM CBCS Pattern]
A. From Unsustainable to Sustainable development.
B. Water conservation, rain water harvesting, watershed management.
C. Resettlement and rehabilitation of people, its problems and concerns.
D. Environmental ethics.
E. Climate change, global warming, acid rain, ozone layer depletion, unclear accidents and holocaust.
F. Wasteland reclamation.
G. Consumerism and waste products.
H. Environmental Legislation.
I. Public awareness.
Water is essential to human existence and ecosystems and a vital element for human development. Thus, water availability is a global issue. Although, water is the most widely occurring substance on Earth, it is a well-known fact that only about 2.5% is fresh water and the rest is salt water. Of the 2.5% of freshwater, its biggest portion is locked up in glaciers and permanent snow cover. Thus, in reality, only about 1 % of the world’s freshwater is readily available and accessible for direct human use.
Water availability is becoming an increasingly crucial issue for Asia. In recent years, evidence indicates that water is becoming increasingly affected by erratic weather patterns, as has already happened to countries such as Indonesia and China, which have experienced droughts and inevitable food shortages.
Reasons for Shortage of Water:
a) Climatic changes
b) Misuse of water by industries and farmers,
c) High Population growth
d) Loss of water during distribution
Aim of Water preservation
Studies show that by 2025 more than half the people around the world will not have enough water. Preservation of water is very essential for the existence of mankind. Water conservation includes all the policies, strategies and activities made to sustainably manage the use of fresh water and to meet its future human demand. That’s why preservation of water is the demand of present world. The goals of water conservation efforts include:
1. Ensuring availability of water for future generations.
2. Energy conservation.
3. Habitat conservation by minimising human water use which helps to preserve fresh water habitats for local wildlife and water quality.
How to conserve water for future?
a) Implementation of drip irrigation to save water.
b) Promotion of recycling and use of water by industries.
c) Construction of dams and water reservoirs to capture rainfall and use such reserve water during draughts.
d) Educate people about the importance of water and motivate them to save water.
e) Regular monitoring of ground water.
f) Research and development in field of water preservation.
Rain water harvesting
Rain water harvesting is one of the most effective methods of water management and water conservation. Rainwater harvesting is the system of collection, accumulation and deposition of rain water with the help of artificially designed system rather than allowing it to run off. It can be collected from rivers or roofs and in many places, the water collected is redirected to a deep pit reservoir with percolation. The harvested water can be used as drinking water, irrigation activities, industrial use, and ground water recharge.
Need and Importance of Rain water harvesting
Rainwater is one of the simplest and oldest methods of self-supply of water for house-holds.
a) It provides an independent water supply in case of shortage of water.
b) It provides water when there is a drought.
c) It helps in the availability of potable water as it is substantially free of salinity.
d) It helps in meeting growing demand of water due to high growth of population.
e) It helps in creating awareness about the importance of water conservation.
f) It is a cheap and reliable source of clean water.
Methods of Rain Water harvesting
Rain water harvesting can be undertaken through a variety of ways
a) Capturing runoff from rooftops – Roof water harvest
b) Capturing runoff from local catchments – Land harvest
c) Capturing seasonal floodwaters from local streams
d) Conserving water through watershed management
e) For Urban & Industrial Environment –
– Roof & Land based RWH
– Public, Private, Office & Industrial buildings
– Pavements, Lawns, Gardens & other open spaces
Advantages of Rain water harvesting
a) Provides self-sufficiency to water supply
b) Reduces the cost for pumping of groundwater
c) Provides high quality water, soft and low in minerals
d) Improves the quality of ground water through dilution when recharged to groundwater
e) Reduces soil erosion in urban areas
f) Rooftop rain water harvesting is less expensive
g) Rainwater harvesting systems are simple which can be adopted by individuals
Watershed Management seeks to manage water supply, the quality of water, drainage, water rights and the overall planning and utilisation of watersheds. It is the study of the relevant characteristics of a watershed aimed at sustainable distribution of its resources and creating and implementing plans and programmes that affect the plant animal and human communities within the watershed boundary. It is an integrated and interdisciplinary approach. It must consider the social, economic and institutional factors operating within and outside the watershed.
Importance of Watershed Management
a) It relates to soil and water conservation in the watershed which includes proper land use, protection of land against all forms of degradation, flood protection, water conservation and harvesting, proper management of surface and ground water. The requirement of watershed management has increased in this time of water shortage.
b) It helps to recharge groundwater. Afforestation of degraded areas is an important aspect of watershed management.
c) Watershed management can preserve water for the existence of a human race and environmental protection.
Now a day one of the major consequences of environmental pollution is the acid rain. It has become serious threat to water bodies like ponds, rivers, lakes and reservoirs and also to the terrestrial eco-system like grassland and forests. Acid rain may be defined as any rain, fog, mist or snow which have more acid than the normal rain having a lower PH as compared to normal rains water. Decrease in the PH value of rain water is caused by the presence of sulphur and nitrogen in the atmosphere.
Sulphur and nitrogen emitted from the burning of fossil fuels like coal, oil in power plants, industrial boilers and car engines. When those pollutants combine with water vapour, sunlight and oxygen in atmosphere, they create a diluted soup of sulphuric and nitric acids. In some heavily industrialised regions, hydrogen chloride gases in the atmosphere produce hydrochloric acid, which is also a form of acid rain.
Rainfall is acidic by nature which have a PH scale of 5.6 but regular pollution increases acidity upto a hundred times the natural level in industrialised areas which causes acid rain. In some cases, acid rain is also caused due to natural factors such as volcano’s eruption.
Effects of acid rain
Acid rain creates complex problems and its impact on eco-system are discussed below:
1. Acid rain increases the soil acidity affecting land flora & fauna.
2. It causes killing of quantic plants and animals.
3. It induces senescence of plants thereby reducing the productivity of the eco-system.
4. It leaches various metals such as aluminium, zinc, copper, manganese, lead etc., from the soil into aquatic bodies.
5. It corrodes buildings, monuments, statues, bridges, fences, railing etc.
6. Acid rain plants and animals are easily attached by pathogens.
7. Diseases caused by bacteria and pathogens can be spread by acid rain water.
8. Acid rain may cause respiratory and skin diseases.
Control of acid rain
1. Emission of Sulphur and nitrogen from industries and power plants should be reduced by using pollution control equipments.
2. Liming of lakes and soils should be done to reduce the adverse effect of acid rain.
3. The use of fuel in driving cars should be economized.
4. Use of green energy to control power plant pollution.
5. Removes sulphur dioxide from flue gas (waste gases)
Depletion of ozone layer
Ozone is a pale blue gas, mostly present in the stratosphere which is extended upto 50 km above the surface of the earth. Ozone strongly absorbs a large portion of
sun’s ultraviolet radiation and thus protects the living organisms on earth from the harmful effects of UV radiations of the sun.
According to environmental scientists, the ozone layer in the stratosphere is gradually depleting by the action of chlorofluorocarbons (CFCs) and oxides of nitrogen. The CFSs often called as Freon (Trade name) are widely used in a variety of goods because they are nontoxic, stable, inert, inexpensive, efficient and easy to handle.
Besides, the burning of Freon products also releases these gases into atmosphere. These gases are highly stable and gradually move into the stratosphere. In the stratosphere, CFCs undergo photolytic dissociation to produce chlorine radical. The chlorine radicals directly attack ozone molecules depleting ozone layer.
Effects of Ozone Layer Depletion
Due to the depletion of ozone layer in the stratosphere, the harmful UV radiation will easily reach the surface of earth causing mass destruction. Some of the harmful effect of UV radiation are listed below:
a) UV radiant can cause skin diseases like skin cancer, leukemia, breast cancer, lung cancer etc.
b) UV radiation may damage the genetic material, DNA leading to nutritional diseases.
c) UV radiation injures plant proteins and causes depletion of chlorophylls mutations.
d) The depletion of ozone layer will induce, eye cancer in cattle.
e) The depletion of ozone layer leads to the loss of various plants from terrestrial and aquatic habitants.
f) It will reduce the crop productivity.
g) It will bring about significant change in the climate.
h) Due to depletion of the ozone layer, UV radiation may cause global warming situation.
The devastating geophysical disturbances and the sudden changes that occur in and around the earth are generally referred to as disasters.
Types of Disaster
Natural Disasters: Natural disasters are earthquakes, floods, cyclones, volcanic eruptions, drought, heavy rains, hailstorms, forest fire, heavy snowfalls, Tsunamis, etc.
Man-made Disasters: Industrial accidents, air crashes, train accidents, attack by terrorists, ethnic clashes, epidemics and fire related accidents are some of the man-made disasters.
How can we prevent man-made disaster?
– Before the Disaster (Precautions, Mass Awareness, Prediction, Preparation, etc.)
– During the occurrence of Disasters (Special steps to be taken as per type of the disaster, search and rescue operation, etc.)
– After the Disaster (Relief and Rehabilitation of the affected, heath services, reconstruction of communication systems, etc.)
Explain the role of students in disaster Management?
Students are obligatory and highly sensitive part of the society. Today’s students are tomorrows citizen. So students can play a vital role in disaster management.
– During earthquake, one should take shelter under the hard frames of the doors, corner of the house, strong table/beds or in open spaces.
– One should never take shelter under electric wire/posts, tall trees, water tanks, windows or furniture with glasses, kitchen, bathrooms.
– The Almirah, rack and furniture in the bedrooms or living rooms should be fixed properly.
– A bag containing of emergency items like drinking water, foods, first aids, whistle, torch lights should be kept near the main entrance of the house for use in an emergency situation.
– Precautionary and prohibitory measures imposed by the administration in such situations should strictly be followed.
Mention the steps to be taken during search and rescue operation.
a) A Rescuers should be calm, composed but firm.
b) A thorough assessment should be made before executing search and rescue operations.
c) A safe distance be maintained from the damaged site.
d) Need to examine the damaged sites thoroughly.
e) First aids to be kept ready round the clock for primary treatment.
What are the things we should not do during disaster?
a) Don’t press the panic button unnecessarily.
b) Rescue operation should not be carried out without proper assessment and equipments.
c) Materials from the damage site should not be taken out in a haphazard manner to evade further damage.
d) No careless movement around the accident site be made, which may further endanger the lives of the victims.
e) If not emergent, no movement around/over the accident site should be done.
Mention two authorities established by govt. of India for disaster management.
a) National Disaster Management authority (NDMA),
b) State Disaster Management Authority (SDMA) and District Disaster Management Authority (DDMA)
Explain the two authorities which established for disaster management in Assam
a) Assam State Disaster Management Authority (ASDMA): The State of Assam has taken special steps to address disasters under the National Disaster Management Act, 2005. The Guidelines of the Assam State Disaster Management Authority was framed in the year 2010. The main functions of these agencies are:
– Community participation.
b) Assam State Disaster Response Force (SDRF):
In order to frame an effective mechanism to deal with disasters, the Assam State Disaster Response Force was created in the year 2010 and recruitment to this organization has been done ever since.
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