Mineral resources: Use and exploitation, environmental effects of extracting and using mineral resources, case studies- food resources, world food problems, changes caused by agriculture and over grazing

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Mineral resources: Use and exploitation, environmental effects of extracting and using mineral resources, case studies- food resources, world food problems, changes caused by agriculture and over grazing

Minerals are valuable natural resources being finite and non-renewable. Minerals in general have been categorized into three classes viz., fuel(coal, gas and petroleum), metallic (Bauxite, laterite, haematite etc) and non-metallic (graphite, diamond, quartz, feldspar).

Fuel minerals like coal, oil and natural gas have been given prime importance as they account for nearly 87% of the value of mineral production whereas metallic and non-metallic constitutes 6 to 7%.

Coal, oil and natural gas are the basic fossil fuel. Proven coal reserves of the country as 1994 as estimated by GSI is about 68 billion tonnes (might get exhausted within  200 years).

We have very poor reserves for petroleum just limited to 700 million tonnes. About 40% of the total consumption of the overall petroleum products of the country is used in road transport sector (in case of diesel, consumption of road transport sector is to the extent of 70% of the total diesel consumption of the country). Rest 60% of the petroleum products are used in industries including power generation, domestic and for miscellaneous purposes.

The proven reserve for natural gas on 1993 works out to be approx. 700 billion cubic meter (BCM). As regard to production vis a vis utilization aspect in earlier years, more than half of gas coming out of the wells remained unutilized. However, in recent years, we have achieved a utilization rate of 80 – 90%. Keeping in view the future demands and proven gas reserves, it is unlikely that our gas reserves might last for more than 20 years.

As per estimates if the present trend of production continues, we will exhaust our reserves of all the important minerals and fuels, except coal, iron ore, lime­stone and bauxite, in 25 to 30 years.

Uses of minerals

The main uses of minerals are as follows:

Development of industrial plants and machinery. Generation of energy e.g. coal, lignite, uranium. (iii) Construction, housing, settlements. Defense equipments weapons, armaments. Transportation means. Communication- telephone wires, cables, electronic devices. Medicinal system- particularly in Ayurvedic System. Formation of alloys for various purposes (e.g. phosphorite). Agriculture – as fertilizers, seed dressings and fungicides (e.g. zineb containing zinc, Maneb-containing manganese etc.). Jewellery– e.g. Gold, silver, platinum, diamond.

The environmental damage caused by mining activities of minerals are

1.   Groundwater contamination

2.   Subsidence of land

3.   Devegetation and defacing of landscape

4.     Occupational Health Hazards

5.     Air pollution

6.     Surface water pollution

Case studies

India is the producer of 84 minerals the annual value of which is about Rs.50,000 crore. At least six major mines need a mention here which are known for causing severe problems:

(i)           Jaduguda Uranium Mine, Jharkhand— exposing local people to radioactive hazards.

(ii)          Jharia coal mines, Jharkhand— underground fire leading to land subsidence and forced displacement of people.

(iii)      Sukinda chromite mines, Orissa— seeping of hexavalent chromium into river posing serious health hazard, Cr6+ being highly toxic and carcinogenic. of groundwater.

(iv)       Kudremukh iron ore mine, Karnataka— causing river pollution and threat to biodiversity. (v) East coast Bauxite mine, Orissa— Land encroachment and issue of rehabilitation unsettled.

(v)        North-Eastern Coal Fields, Assam— Very high sulphur contamination

 

Environmental effect of using Fossil fuels

The United States holds less than 5% of the world's population, but due to large houses and private cars, uses more than 25% of the world's supply of fossil fuels. As the largest source of world greenhouse gas emissions, CO­­₂ from fossil fuel combustion, accounted for 80 percent of weighted emissions. Combustion of fossil fuels also produces other air pollutants, such as nitrogen oxides, sulfur dioxide, volatile organic compounds and heavy metals.

"The electricity sector is unique among industrial sectors in its very large contribution to emissions associated with nearly all air issues. Electricity generation produces a large share of nitrogen oxides and sulphur dioxide emissions, which contribute to smog and acid rain and the formation of fine particulate matter. It is the largest uncontrolled industrial source of mercury emissions in Canada. Fossil fuel-fired electric power plants =======also emit carbon dioxide, which may contribute to climate change. In addition, the sector has significant impacts on water and habitat and species.

Combustion of fossil fuels generates sulfuric, carbonic, and nitric acids, which fall= to Earth as acid rain, impacting both natural areas and the built environment. Monuments and sculptures made from marble and limestone are particularly vulnerable, as the acids dissolve calcium carbonate.

Fossil fuels also contain radioactive materials, mainly uranium and thorium, which are released into the atmosphere. In 2000, about 12,000 tonnes of thorium and 5,000 tonnes of uranium were released worldwide from burning coal. It is estimated that during 1982, US coal burning released 155 times as much radioactivity into the atmosphere as the Three Mile Island accident.

Burning coal also generates large amounts of bottom ash and fly ash. These materials are used in a wide variety of applications, utilizing, for example, about 40% of the US production.

Harvesting, processing, and distributing fossil fuels can also create environmental concerns. Coal mining methods, particularly mountaintop removal and strip mining, have negative environmental impacts, and offshore oil drilling poses a hazard to aquatic organisms. Oil refineries also have negative environmental impacts, including air and water pollution. Transportation of coal requires the use of diesel-powered locomotives, while crude oil is typically transported by tanker ships, each of which requires the combustion of additional fossil fuels.

Although the use of fossil fuels may seem beneficial to our lives, this act is playing a role on global warming and it is said to be dangerous for the future.

Moreover, these environmental pollutions impacts on the human beings because its particles of the fossil fuel on the air cause negative health effects when inhaled by people. These health effects include premature death, acute respiratory illness, aggravated asthma, chronic bronchitis and decreased lung function. So, the poor, undernourished, very young and very old, and people with preexisting respiratory disease and other ill health, are more at risk

Food resources

Although the earth has approximately 30,000 plants species with parts that people can eat , only 15 plants and 8 animals species supply 90% of our food.

Types of food supply

1. Crop plants: Mostly produce grains about 76% of the world’s food. e.g rice, wheat and maize. Domesticated animals (cattle , sheep , goat , etc.) These animals are the source of milk and meat . these form the important component of the diet of the people all over the world.ØWheat and rice as their staple food.

2. Range lands: It produces 17% of world’s food from trees and grazing animals. e.g fruits, milk and meat

3. Ocean: Fisheries – 7% of world’s food

World food problem

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. 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.

Under nutrition is problem in poor countries. People who cannot buy enough food to meet their basic energy needs suffer from under nutrition. They receive less than 90% of this minimum dietry calorie. Effect of under nutrition: Suffer from mental retardation and infectious diseases.

Malnutrition can be defined as lack of specific components of food such as proteins, vitamins, or essential chemical elements (iron and iodine). Deficiency leads to malnutrition resulting in several diseases. Anemia is caused due to inability to absorb iron. Goiter is caused due to iodine deficiency that leads to mental retardation and deaf mustism. Pellagra may be due to deficiency of tryptophan, lysine and vitamins. Blindness may be caused due to inadequate supply of Vitamin A.

Malnutrition may occur in both rich and poor countries. 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

Changes Caused by Agriculture and Overgrazing 

From centuries, agriculture is providing inputs to large number of industries involved in production, processing and distribution of food. Accordingly, agriculture has significant effect on environment. The effects of agriculture on environment can be classified as local, regional, and global level. The agriculture also makes impact on the usage of land generally as follows:

1.   Loss of genetic diversity

As modern agriculture converts an ever-increasing portion of the earth's land surface to monoculture, the genetic and ecological diversity of the planet erodes. Both the conversion of diverse natural ecosystems to new agricultural lands and the narrowing of the genetic diversity of crops. 

2.   Fertilizer related problems

Application of fertilizers can be a serious problem of pollution and can create number of problems. Excessive level of nitrates in ground water has created problems in developed countries. These are:

a. Accumulated phosphorous as a consequence of use of phosphoric fertilizer are posing serious threat as residues in domestic water supply and for ecology of river and other water bodies. Increased level of phosphates in different water results in eutropication.

b. Effect of chemical fertilizer is long term, therefore leads to net loss of soil organic matter.

c. Micronutrient imbalance due to depletion of nutrients

3. Pesticide related problems

To control insects, pests, diseases and weeds which are responsible for reduction in productivity different chemicals are used as insecticides, pesticides and herbicides. Successful control of insects, pests and weeds increases productivity and reduces losses and provide security for harvest and storage. Applications of these synthetic chemicals have great economic values and at the same time cause number of serious problems such as:

a. Affects human health which includes acute poisoning and illness caused by higher doses and accidental exposes

b. As long term effect, cause cancer, birth defects, Parkinson’s disease and other regenerative diseases.

c. Long term application of pesticides can affect soil fertility.

d. Danger of killing beneficial predators.

e. Pesticides resistance and pest resurgence

f. Creation of super weed

g. Accumulation of pesticides in food chain/biomagnifications. 

 

Cotton growing belt of Punjab which covers Abohar, Fazalka and part of Bathinda indicates that over use of pesticides for control of insect pest in cotton to enhance productivity has not only affected soil health, but also caused cancer in human being.

4. Water Logging

High water table or surface flooding can cause water logging problems Water logging may lead to poor crop productivity due to anaerobic condition created in the soil. In India, deltas of Ganga, Andaman and Nicobar Islands and some areas of Kerala are prone to frequent water logging.

5. Salinity

Due to adoption of intensive agriculture practices and increased concentration of soluble salts leads to salinity. Due to poor drainage, dissolved salts accumulate on soil surface and affects soil fertility. Excess concentration of these salts may form a crust on the surface which may injurious to the plants. The water absorption process is affected and uptake of nutrient is disturbed. According to an estimate, in India, 7 million hectare of land is saline and area is showing in increasing trends due to adoption of intensive agriculture practises.

Changes caused due to Over grazing:

1.           Land degradation: Over grazing removes the cover of vegetation exposed soil gets compacted soil moisture is not available Over grazing leads to poor, dry and compacted soil. Land can not be used for further cultivation.

2. Soil erosion: When the grasses are removed the soil becomes loose and gets eroded by the action of wind and rain fall.

3. Loss of useful species: Over grazing affects the plant population and their regenerating capacity. Over grazing replace the plant of high nutritive value with plant of low nutritive value.

Diclofenac is the drug for veterinary use to treat the livestocks which have strong residual nature, banned in India since 2006, which leads to high persistence throughout the food chain. Due to biomagnification it becomes more dangerous to the vultures as they are consumers of diclofenac treated cattle. Diclofenac is responsible for bringing three South Asian species of Gyps vultures to the brink of extinction.