GURU GOBIND SINGH INDRAPRASTHA UNIVERSITY

ENVIRONMENTAL SCIENCE

Unit 2

Question banks

1. Explain Natural resources?
   1. Renewable and non renewable resources

Renewable Resource is energy which is generated from natural sources i.e. sun, wind, rain, tides and can be generated again and again as and when required. They are available in plenty and by far most the cleanest sources of energy available on this planet. Solar Energy, Wind Energy, Geothermal Energy, Biomass Energy from Plants, Tidal Energy are the examples of Renewable resources.

Non Renewable Resource is a natural resource that cannot be re-made or re- grown at a scale comparable to its consumption. Non-renewable sources are not environmental friendly and can have serious effect on our health.  They are called non-renewable because they cannot be re-generated within a short span of time.  Non-renewable sources exist in the form of fossil fuels, natural gas, oil and coal

2.    Explain Natural resources and associated problems?

Any material which can be transformed in a way that it becomes more valuable and useful can be termed as resource. In other words, it is possible to obtain valuable items from any resources. Resource, therefore, are the means to attain given ends. The aspect of satisfaction is so important that we consider a thing or substance a resource, as so long it meets our needs. Life on this planet depends upon a large number of things and services provided by the nature, which are known as Natural Resources. Thus water, air, soil, minerals, coal, forests, crops and wild life are all examples of natural resources.

Problems associated with natural resources

1. The unequal consumption of natural resources

A major part of natural resources today are consumed in the technologically advanced or ‘developed’ world, usually termed ‘the west’. The ‘developing nations’ of ‘the east’, including India and China, also over use many resources because of their greater human population. However, the consumption of resources per capita (per individual) of the developed countries is up to 50 times greater than in most developing countries. Advanced countries produce over 75% of global industrial waste and greenhouse gases.

2. Planning land use

Land is a major resource, needed for not only for food production and animal husbandry, but also for industry and growing human settlements. These forms of intensive land use are frequently extended at the cost of ‘wild lands’, our remaining forests, grasslands, wetlands and deserts. This demands for a pragmatic policy that analyses the land allocation for different uses.

3. The need for sustainable lifestyles

Human standard of living and the health of the ecosystem are indicators of sustainable use of resources in any country or region. Ironically, both are not in concurrence with each other. Increasing the level of one, usually leads to degradation of other. Development policies should be formulated to strike a balance between the two.

3.    Explain uses and over exploitation of Forest resources?

1. Use and over exploitation

A forest is a biotic community predominantly of trees, shrubs and other woody vegetation, usually with a closed canopy. This invaluable renewable natural resource is beneficial to man in many ways.

The direct benefits from forests are:

(a) Fuel Wood:

Wood is used as a source of energy for cooking purpose and for keeping warm.

(b) Timber:

Wood is used for making furniture, tool-handles, railway sleep­ers, matches, ploughs, bridges, boats etc.

(c) Bamboos:

These are used for matting, flooring, baskets, ropes, rafts, cots etc.

(d) Food:

Fruits, leaves, roots and tubers of plants and meat of forest animals form the food of forest tribes.

(e) Shelter:

Mosses, ferns, insects, birds, reptiles, mammals and micro-organ­isms are provided shelter by forests.

(f) Paper:

Wood and Bamboo pulp are used for manufacturing paper (News­print, stationery, packing paper, sanitary paper)

(g) Rayon:

Bamboo and wood are used in the manufacture of rayon (yarns, artificial silk-fibres)

(h) Forest Products:

Tannins, gums, drugs, spices, insecticides, waxes, honey, horns, musk, ivory, hides etc. are all provided by the flora and fauna of for­ests.

Over exploitation of forests

Forests contribute substantially to the national economy. With increasing population increased demand of fuel wood, expansion of area under urban development and industries has lead to over exploitation of forest .At present international level we are losing forest at the rate of 1.7 crore hectares annually. Overexploitation also occurs due to overgrazing and conversion of forest to pastures for domestic use.

4.    Define Deforestation and explain two case studies ?

Deforestation means reckless or large-scale felling or cutting of trees by man for commercial and other purposes. Deforestation refers to the decrease in forest areas across the world that are lost for other uses such as agricultural croplands, urbanization, or mining activities.

1. Case studies

1. Jhum cultivation

Jhum Agriculture or shifting agriculture has destroyed large number of hectare of forest tracts in North-Eastern states and Orissa. Jhum agriculture is subsidence agriculture in which tract of forest land is cleared by cutting trees and it is used for cultivation. After few years, when productivity of the land decreases, cultivators abandon the land and clear next tract. As a result of this practise, combined with increasing population there is rapid deforestation as more and more cultivators clear forest to cultivate land. Also, with increase in population there is cultivators are forced to return to previous tracts of land in relatively shorter durations, not allowing the land to regain its productivity.

2. Chipko movement

The Chipko movement or Chipko Andolan is a social-ecological movement that practised the Gandhian methods of satyagraha and non-violent resistance, through the act of hugging trees to protect them from being felled. The modern Chipko movement started in the early 1970s in the Garhwal Himalayas of Uttarakhand,with growing awareness towards rapid deforestation. The landmark event in this struggle took place on March 26, 1974, when a group of peasant women in Reni village, Hemwalghati, in Chamoli district, Uttarakhand, India, acted to prevent the cutting of trees and reclaim their traditional forest rights that were threatened by the contractor system of the state Forest Department. Their actions inspired hundreds of such actions at the grassroots level throughout the region. By the 1980s the movement had spread throughout India and led to formulation of people-sensitive forest policies, which put a stop to the open felling of trees in regions as far reaching as Vindhyas and the Western Ghats.

5.    Explain use and over exploitation Water resources

Use and over exploitation of surface and ground water

Water resources are sources of water that are useful or potentially useful. • Uses of water include agricultural, industrial, household, recreational and environmental activities. • Virtually all of these human uses require fresh water

Water Resources-Use and Overutilization :

1. The water Cycle through evaporation and precipitation, maintains hydrological systems .
2. All aquatic ecosystems are used by a large number for their daily needs such as washing irrigation, cooking etc.
3. One of the greatest challenges today is the management of these water resources.
4. Due to increasing population there is an enormous supply for the available freshwater resources. India is likely to face water crisis by 2025.
5. With growth of human population larger amounts of water will be required to fulfil basic needs Today in many areas this need cannot be met.
6. Overutilization of water occurs at various levels:
7. Most people use more water than required to carry out basic activities such as brushing, bathing, washing and cleaning etc.
8. Farmers also sometimes use double the water required for irrigation.
9. There are many ways in which the farmer can increase the yield by using less water for irrigation.
10. With the growth of human population there is an increasing need for larger amounts of water to fulfil a variety of basic needs. Today in many areas this requirement cannot be met.
11. Overutilization of water occurs at various levels. Most people use more water than really needed. Most of us waste water during a bath by using shower or during washing of clothes. Many agriculturists use more water than necessary to grow crops. There are many ways in which farmers can use less water without reducing the yields such as the use of drip irrigation systems.
12. Agriculture also pollutes surface water and underground water stores by the excessive use of chemical fertilizers and pesticides. Methods such as the use of biomass as fertilizers and non toxic pesticides such as neem products reduces the agricultural pollution of surface and ground water.

Industry tends to maximise short-term economic gains by not bothering about its liquid waste and releasing it into the streams, rivers, sea.

1. Use and exploitation

Uses of Minerals

Due to increased population, there is increased demand of minerals by the industry, transport, agriculture and defence preparation. Depletion of almost all known and easily accessible deposits is anticipated in near future. Moreover, there may be shortage of some crucial elements such as mercury, tin, copper, gold, silver and platinum. The limited resource of phosphorus, which is an essential component of chemical fertilizers, is another area of concern. 

Exploitation of Minerals

• Depending on their use, mineral resources can be divided into several broad categories such as elements for metal production and technology, building materials, minerals for the chemical industry and minerals for agriculture. When usually we think about mineral resources we often think of metals but the predominant mineral resources are not metallic. The picture of annual world consumption of some elements is as under:

• Sodium and iron are used at a rate of about 0.1 to 1.0 billion metric tons per year.
• Nitrogen, sulphur, potassium and calcium are primarily used as fertilizers at a rate of about 10 to 100 million metric tons per year.
• Zinc, copper, aluminium and lead are used at a rate of about 3 to 10 million metric tons per year;
• Gold and silver are used at a rate of about 10 thousand metric tons per year.
• Out of all the metallic minerals, iron consumption is 95% of the metals consumed

Thus, with the exception of iron, the non-metallic minerals are consumed at much greater rates than the elements used for their metallic properties.

Environmental Impacts of Mineral Extraction

Extracting and use of mineral resources can affect the environment adversely. Environmental affect may depend on factors such as mining procedures, ore quality, climate, size of operation, topography, etc. Some of major environmental impacts of mining and processing operations are as under

1. Degradation of land.

2. Pollution of surfaces and ground water resources.

3. Effect on growth of vegetation due to leaching out effect of minerals.

4. Surface water pollution and groundwater contamination lead to occupational health hazards etc.

5. Air pollution due to emission of gases.

6. Deforestation affects flora and fauna.

7. Rehabilitation of affected population.

As per estimates of Food and Agriculture Organization (FAO), about 840 million people remain chronically hungry and out of this 800 million are living in the developing world. In last decade, it is decreasing at the rate of 2.5 million per year, but at the same time world’s population is increasing. Target of cutting half the number of world’s chronically hungry and undernourished people by 2015 will difficult to meet, if the present trend continues. Due to inadequate purchasing power to buy food, it is difficult to fulfil minimum calorific requirement of human body per day. Large number of people are in India are poor which can be attribute to equitable distribution of income. Food insufficiency can be divided into two categories into under-nourishment and malnourishment. Both of these insufficiencies are global problems.

1. Under-nourishment

The FAO estimates that the average minimum daily caloric intake over the whole world is about 2,500 calories per day. People who receive less than 90% of their minimum dietary intake on a long-term basis are considered undernourished. Those who receive less than 80% of their minimum daily caloric intake requirements are considered ‘seriously’ undernourished. Children in this category are likely to suffer from stunted growth, mental retardation, and other social and developmental disorders. Therefore, Under-nourishment means lack of sufficient calories in available food, resulting in little or no ability to move or work.

Person may have excess food but still diet suffers from due to nutritional imbalance or inability to absorb or may have problem to utilize essential nutrients. If we compare diet of the developed countries with developing countries people in developed countries have processed food which may be deficient in fibre, vitamins and other components where as in the diet of developing countries, may be lack of specific nutrients because they consume less meat ,fruits and vegetables due to poor purchasing power .

Malnourishment can be defined as lack of specific components of food such as proteins, vitamins, or essential chemical elements.

• Marasmus: a progressive emaciation caused by lack of protein and calories.
• Kwashiarkor: a lack of sufficient protein in the diet which leads to a failure of neural development and therefore learning disabilities.
• Anemia: it is caused by lack of iron in the diet or due to an inability to absorb iron from food.
• Pellagra: it occurs due to the deficiency of tryptophan and lysine, vitamins in the diet.

Every year, food problem kill as many people as were killed by the atomic bomb dropped on Hiroshima during World War II. This shows that there is drastic need to increase food production, equitably distribute it and also to control population growth. Although India is the third largest producer of staple crops, it is estimated that about 300 million Indians are still undernourished. India has only half as much land as USA, but it has nearly three times population to feed. Our food problems are directly related to population.

10.           What are the Individual’s role in conservation of natural resources?

Different natural resources like forests, water, soil, food, mineral and energy resources play a vital role in the development of a nation. While conservation efforts are underway at National as well as International level, the individual efforts for conservation of natural resources can go a long way.

1. Conserve Water

• Don't keep water taps running while brushing, shaving, washing or bathing.
• Check for water leaks in pipes and toilets and repair them promptly. A small pin-hole sized leak will lead to the wastage of 640 liters of water in a month.
• Use drip irrigation and sprinkling irrigation to improve irrigation efficiency and reduce evaporation. Install a small system to capture rain water and collect normally wasted used water from sinks, cloth-washers, bathtubs etc. which can be used for watering the plants

2.     Conserve energy

• Turn off lights, fans and other appliances when not in use.
• Obtain as much heat as possible from natural sources. Dry the clothes in sun instead of drier if it is a sunny day.
• Use solar cooker for cooking your food on sunny days which will be more nutritious and will cut down on your LPG expenses.

3.     Protect the soil

• While constructing your house, don't uproot the trees as far as possible. Plant the disturbed areas with a fast growing native ground cover.
• Make compost from your kitchen waste and use it for your kitchen-garden or flower-pots. Do not irrigate the plants using a strong flow of water, as it would wash off the soil.

4.     Promote Sustainable Agriculture

• Do not waste food. Take as much as you can eat Reduce the use of pesticides.
• Fertilize your crop primarily with organic fertilizers.