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carbonaceous material but its origins lie in the plant material found in the swamps and forests that used to cover much of the earth’s surface 300 million years ago. As seas advanced and receded over the land, successive layers of plant material and sediment were built up. The weight of this material, and tectonic movement provided the necessary temperature and pressure conditions which have ultimately produced the limestone strata and coal seams exploited in our coal mines today.

It is interesting to consider that the origin of coal is the chemical energy that was stored in plant material by photosynthesis of the sun’s rays hundreds of millions of years ago.

The coal mining technique depends upon the shape and depth of the coal seam that is being stripped. There are two approaches:

open-cast mining - where coal seams are horizontal and relatively near the surface. This is inexpensive, yet coal seams tend to be of lower purity and quality

deep shaft mining - where vertical and horizontal shafts are used to access the coal face deep underground. Deep shaft mining gives access to better quality coal seams but is more expensive than open cast mining and in the past has been a very hazardous industry.

How coal is mined depends mainly on how deep the coal bed lies from the surface and on local geologic conditions. If the coal is within 200 feet (60 meters) or less of the surface, the mine will be a surface, or open-pit (also called open-cut), mine. If the coal is in hilly terrain or is too deep for surface mining to be feasible, an underground mine will be opened.

Underground modes of access include drift, slope, and shaft mining, and actual mining methods include longwall, highwall and room and pillar mining. Drift mines enter horizontally into the side of a hill and mine the coal within the hill. Slope mines usually begin in a valley bottom, and a tunnel slopes down to the coal to be mined. Shaft mines are the deepest mines; a vertical shaft with an elevator is made from the surface down to the coal.

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In room and pillar mining, the most common type of underground coal mining, coal seams are mined by a «continuous miner» that cuts a network of «rooms» into the seam. As the rooms are cut, the continuous miner simultaneously loads the coal onto a shuttle or ram car where it will eventually be placed on a conveyor belt that will move it to the surface. «Pillars» composed of coal are left behind to support the roof of the mine. Each «room» alternates with a «pillar» of greater width for support. Using this mining method normally results in a reduction in recovery of as much as 60 percent because of coal being left in the ground as pillars. As mining continues, roof bolts are placed in the ceiling to avoid ceiling collapse. Under special circumstances, pillars may sometimes be removed or «pulled» toward the end of mining in a process called «retreat mining.» Removing support during retreat mining can lead to roof falls, so the pillars are removed in the opposite direction from which the mine advanced: hence the term «retreat mining.»

Most underground coal is mined by the room and pillar method, whereby rooms are cut into the coal bed leaving a series of pillars, or columns of coal, to help support the mine roof and control the flow of air. Generally, rooms are 20-30 feet wide and the pillars up to 100 feet wide. As mining advances, a grid-like pattern of rooms and pillars is formed. When mining advances to the end of a panel or the property line, retreat mining begins. In retreat mining, the workers mine as much coal as possible from the remaining pillars until the roof falls in. When retreat mining is completed, the mined area is abandoned.

There are two types of room and pillar mining--conventional mining and continuous mining. Conventional mining is the oldest method and accounts for only about 12% of underground coal output. In conventional mining, the coal seam is cut, drilled, blasted and then loaded into cars. Continuous mining is the most prevalent form of underground mining, accounting for 56% of total underground production. In continuous mining, a machine known as a continuous miner cuts the coal from the mining face, obviating the need for drilling and blasting.

Longwall mining is another type of underground mining. Mechanized shearers are used to cut and remove the coal at the face of the mine. After the coal is removed, it drops onto a chain conveyor, which moves it to a second conveyor that will ultimately take the coal to the surface. Temporary hydraulic-powered roof supports hold up the roof as the extraction process proceeds. This method of mining has proven to be more efficient than room and pillar mining, with a recovery rate of nearly 75 percent, but the equipment is more expensive than conventional room and pillar equipment. As mining continues, roof bolts are placed in the ceiling to avoid ceiling collapse. In longwall mining, only the main tunnels are bolted. Most of the longwall panel is allowed to collapse behind the shields (which hold the roof as coal is excavated).

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Highwall is another method of deep mining, in which a continuous miner is controlled remotely from outside the mine. The miner is guided along the seam, drilling holes in excess of 500 feet, extracting coal that falls to a conveyor belt and is carried to the surface. The highwall mining units require a large capital investment, but mine labor costs are lower because a full crew is unnecessary.

Surface-mining methods include area, contour, mountaintop removal, and auger mining. Area mines are surface mines that remove shallow coal over a broad area where the land is fairly flat. Huge dragline shovels commonly remove rocks overlying the coal (called overburden). After the coal has been removed, the rock is placed back into the pit. Contour mines are surface mines that mine coal in steep, hilly, or mountainous terrain. A wedge of overburden is removed along the coal outcrop on the side of a hill, forming a bench at the level of the coal. After the coal is removed, the overburden is placed back on the bench to return the hill to its natural slope. Mountaintop removal mines are special area mines used where several thick coal seams occur near the top of a mountain. Large quantities of overburden are removed from the top of the mountains, and this material is used to fill in valleys next to the mine. Augur mines are operated on surface-mine benches (before they are covered up); the coal in the side of the hill that can’t be reached by contour mining is drilled (or augured) out.

Draglines are a key element in the high productivity of modern surface mines. They are large excavating machines used to remove the overburden or layers of earth, rock and other material covering a coal seam. The dragline has a large bucket, suspended by cables from the end of a huge boom, which may be as long as 300 feet and is able to scoop up great amounts of overburden as it is dragged across the excavation area. Some buckets have capacities of up 250 tons. The dragline, which can walk on huge pontoon like feet, is one of the largest land based machines in the world.

Among other equipment which has made surface mining the most productive method of coal extraction are electric power shovels which are used to remove overburden and load coal; huge bucket wheel excavators, also employed in the overburden removal process; trucks, which haul both rock and coal from the mine site and sophisticated covered conveyor systems, which deliver coal to nearby preparation plants and eventually on to the customer. High tech advances in metallurgy, engines and electric motors have made possible development of these large and sophisticated machines.

Computer assisted machinery allows more autonomous mining. These include guidance systems for navigation; onboard computers to self diagnose maintenance problems; intelligent signal processing for coal interface detection; natural language processing and computer graphics

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for worker machine interaction; as well as automated technology for other mining functions.

The surface coal mining industry is guided by one major principal: the right of coal extraction carries with it the responsibility of restoring the land to its original or better condition. To assist in this effort, some companies utilize computer aided reclamation design to develop exact profiles on the site and monitor progress. In addition, aerial photography can be employed to document the success of ongoing reclamation efforts.

Surface mining is as much a land reclamation process as it is a way of extracting coal. Ultimately reclaimed sites are returned to many productive uses such as recreation areas, golf courses, wildlife preserves, parks, farms, wetlands, housing developments and pastures.

Coal mining is a hazardous industry which has been made vastly safer through the application of modern and sophisticated machinery. However, it still requires working deep underground in tightly controlled spaces with the inherent risks of roof collapse, explosion, flooding and the harmful effects of a dust laden atmosphere. Explosion presents a very significant risk. Methane gas becomes trapped in pockets within the coal and in suitable mixture with air (around 5%), can be ignited by a spark with catastrophic consequences. Other less immediate dangers are the continued exposure to coal dust which can cause bronchial diseases in mine workers, the most well known being ‘silicosis’.

Coal contains ash and impurities (sulphur, heavy metals and others) that are released on combustion and are damaging to the environment. Various technologies may be employed in power stations to limit their release, however the extent to which they are applied depends upon environmental legislation on a country by country basis.

Coal power stations use washed coal which contains less dust and organic matter. The coal is generally pulverised and blown into the combustion chamber to ignite and combust efficiently in a specially designed burner. Ash and clinker is collected from the base of boiler and particulate dust is removed from the exhaust gases using an electrostatic precipitation filter. This is simply a large chamber filled with vertically hanging wires which have a small electrical charge to which the dust particles are attracted.

More sophisticated and modern power stations will also have flue gas desulphurisation units which will scrub out emissions of SO2 from the exhaust. This process has become increasingly important due to the effects of acid rain resulting from power station emissions and the increasing cost of high quality (low sulphur) coal. Cleaner coal technologies currently being developed will gasify the coal rather than use direct combustion. The gas can be fired directly into a gas turbine which will raise efficiency. Another benefit of gasification is that the gas can be cleaned of impurities prior to combustion.

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Coal reserves are found all over the world. Europe has a long tradition of coal mining, but due to a reliance on expensive deep shaft mining the industry has contracted rapidly in the past twenty years. Eastern Europe, Russia and Ukraine are still major coal producers and exporters. The newest coal producers are countries such as Colombia, Australia, Canada and South Africa which operate massive open-cast mines and export a high proportion of their output. China, India and Korea have extensive coal resources but export little as it is needed to provide for their internal consumption. Present estimates of world coal resources are around 10 million tonnes which would satisfy the world’s present energy demand for 2000 years. Although coal seems to present a long term solution to man’s energy needs, coal combustion has major impacts on local and global environments. Research into cleaner coal technologies may provide solutions which can satisfactorily reduce the environmental effects associated with present coal usage.

IV. Knowing Ins and Outs

Fill in the spaces to complete temperate, boreal and tropical forest types.

1. Evergreen ___________ forest

Natural forest with > 30% canopy cover, in which the canopy is predominantly (> 75%) needleleaf and evergreen.

2. _____________needleleaf forest

Natural forests with > 30% canopy cover, in which the canopy is predominantly (> 75%) needleleaf and deciduous.

3. _______________broadleaf/needleleaf forest

Natural forest with > 30% canopy cover, in which the canopy is composed of a more or less even mixture of needleleaf and broadleaf crowns (between 50:50% and 25:75%).

4. Broadleaf ____________ forest

Natural forests with > 30% canopy cover, the canopy being > 75% evergreen and broadleaf.

5. _______________broadleaf forest

Natural forests with > 30% canopy cover, in which > 75% of the canopy is deciduous and broadleaves predominate (> 75% of canopy cover).

6. Freshwater ____________ forest

Natural forests with > 30% canopy cover, composed of trees with any mixture of leaf type and seasonality, but in which the predominant environmental characteristic is a waterlogged soil.

7. ________________dry forest

Natural forest with > 30% canopy cover, in which the canopy is mainly composed of sclerophyllous broadleaves and is > 75% evergreen.

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8. ______________natural forest

Any forest type above that has in its interior significant areas of disturbance by people, including clearing, felling for wood extraction, anthropogenic fires, road construction, etc.

9. Sparse trees _________ parkland

Natural forests in which the tree canopy cover is between 10-30%, such as in the steppe regions of the world. Trees of any type (e.g., needleleaf, broadleaf, palms).

10. ______________species plantation

Intensively managed forests with > 30% canopy cover, which have been planted by people with species not naturally occurring in that country.

11. ______________ forest plantation

Forest plantations showing extent only with no further information about their type, This data currently only refers to the Ukraine.

12. _____________evergreen broadleaf rain forest

Natural forests with > 30% canopy cover, below 1200m altitude that display little or no seasonality, the canopy being >75% evergreen broadleaf.

13. Lower ____________forest

Natural forests with > 30% canopy cover, between 1200-1800m altitude, with any seasonality regime and leaf type mixture.

14. ______________ montane forest

Natural forests with > 30% canopy cover, above 1800m altitude, with any seasonality regime and leaf type mixture.

15. __________________swamp forest

Natural forests with > 30% canopy cover, below 1200m altitude, composed of trees with any mixture of leaf type and seasonality, but in which the predominant environmental characteristic is a waterlogged soil.

16. Semi-evergreen moist _______________forest

Natural forests with > 30% canopy cover, below 1200m altitude in which between 50-75% of the canopy is evergreen, > 75% are broadleaves, and the trees display seasonality of flowering and fruiting.

17. _________________broadleaf/needleleaf forest

Natural forests with > 30% canopy cover, below 1200m altitude, in which the canopy is composed of a more or less even mixture of needleleaf and broadleaf crowns (between 50:50% and 25:75%).

18. ____________________forest

Natural forest with > 30% canopy cover, below 1200m altitude, in which the canopy is predominantly (> 75%) needleleaf.

19. Mangroves

Natural forests with > 30% canopy cover, composed of species of mangrove tree, generally along coasts in or near brackish or salt water.

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20. Disturbed ______________forest

Any forest type above that has in its interior significant areas of disturbance by people, including clearing, felling for wood extraction, anthropogenic fires, road construction, etc.

21. Deciduous/semi-deciduous __________________forest

Natural forests with > 30% canopy cover, below 1200m altitude in which between 50-100% of the canopy is deciduous and broadleaves predominate (> 75% of canopy cover).

22. _____________________dry forest

Natural forests with > 30% canopy cover, below 1200m altitude, in which the canopy is mainly composed of sclerophyllous broadleaves and is > 75% evergreen.

23. _________________ forest

Natural forests with > 30% canopy cover, below 1200m altitude, in which the canopy is mainly composed of deciduous trees with thorns and succulent phanerophytes with thorns may be frequent.

24. _____________trees and parkland

Natural forests in which the tree canopy cover is between 10-30%, such as in the savannah regions of the world. Trees of any type (e.g., needleleaf, broadleaf, palms).

25. _____________species plantation

Intensively managed forests with > 30% canopy cover, which have been planted by people with species not naturally occurring in that country.

26. ______________species plantation

Intensively managed forests with > 30% canopy cover, which have been planted by people with species that occur naturally in that country.

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V. Enhancing Skills in English-Russian Interpretation

Render orally the following text:

World’s forests

“The forest is a peculiar organism of unlimited kindness and benevolence that makes no demands for its sustenance and extends generously the products of its live activity; it offers protection to all beings offering shade even to those who destroy it.” Buddha

Members of the human species are children of the forest. The evolution of civilization is intertwined with forests; at the center of our history lies the story of their use. Our ancestors believed that gods

inhabit the forests, living in the trees. Remnants of these beliefs underlie the strong feelings many people still have about forests and provoke intensely passionate debates over the way they are used.

Forests of one sort or another have existed for something like 300 million years, humans for perhaps one million. In our short span we have been both destroyers and creators of forests. Today, after several thousand years of forest use, eighty percent of the five-billion-hectare, pre-agricultural-era forest remains, covering about one-third of the earth’s surface. Because of the explosive growth of population during the past century, this gives each individual slightly less than three-quarters of a hectare of forestland.

There is enormous diversity in the world’s forests. No two hectares are identical. There are broad types of forests, however, each type determined by the varied influences of geography and climate. Tropical forests occupy a broad area along the Equator, in Central and South America, Africa and Southeast Asia. Tropical forests have super hot temperatures all year long and get up to 80 inches (2000 mm) of rain a year. Tropical rainforests are home to jaguars, toucans, gorillas and even tarantulas. Here you can also find an antelope called the royal antelope that is only as big as a rabbit. Variations in these forests are caused by the amount of rainfall, which declines as the distance from the Equator increases. Tropical rain forests run along the Equator. Their most notable characteristic is the wide diversity of species they contain. There is an extraordinary variety of trees, hundreds of different species per square mile. The Amazon forest, for instance, hosts about 6,000 tree species. Relatively few of them are commercially valuable, and harvesting timber in these forests is both economically and ecologically challenging. Beautiful and essential to the Earth’s eco-system, these forest are now under a severe and immediate threat. Palm trees also occur in these forests, namely coconut palm, betel, oil and date palms. In tropical forests leaf fall, flowering and fruiting are not seasonal but continuous.

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As the distance from the Equator increases, and rainfall declines, the tropical seasonal forests merge into dry savanna forests. Almost a third of the land surface of the world is arid, with high temperatures during the daytime and very cold temperatures during the night-time. Such deserts occur in Australia, India, Southern Arabia, Africa and in both North and South America. Savannah-type forests occur in North America where there is heavy rainfall: on the open prairies of Canada east of the Rockies, and on the plains of the United States as far south as the Gulf of Mexico. As rain levels drop even further, the savanna forests give way to dry, scrub woodlands consisting mostly of hardy bushes and shrubs.

In the Northern Hemisphere, at the greatest distance from the Equator, lie the boreal coniferous forests. They occupy two areas: a broad band across North America, from Alaska to Newfoundland; and across northern Europe and Asia, from Scandinavia to the Siberian Pacific. In this region there is a short, intense growing season, offset by long cold winters during which tree growth ceases. Boreal forests often get less rain than the other forests and are home to evergreen trees, which stay green all year long. This is because they have needles, which don’t need as much water as regular tree leaves. There are relatively few tree species, almost all coniferous, and large areas of land are covered with a single species, in part due to the frequency of intense fires which sweep through these forests. Various types of pines and spruces dominate in the boreal forest; birch and aspen are the major deciduous species.

The broad, mid-latitudinal area lying between the tropical and boreal zones contains a variety of different forest types. Perhaps the most important are the northern temperate deciduous forests found in the northeastern United States, Western Europe, Korea and China. Temperate forests have four distinct seasons, which means all the tree leaves fall off in the winter months. Tons of animals live in temperate forests like beavers, black and brown bears, deer, foxes, raccoons, skunks, rabbits and various bird species. Compared to the tropics there are few species, the most prominent including the various oaks, maples, ash, beech, birch and elm. Through human history many of these species have been widely used, and their cultivation has, in many cases, become highly developed. Conifers also grow in these forests, but to a lesser degree.

Because of mild temperatures in the Temperate Zone, decomposition of forest litter is almost continuous, and a large portion of the nutrients is stored in the soil. Consequently, these soils are well suited to agriculture and extensive areas have been cleared for growing food crops. This factor has contributed to the concentrated growth of industrialized societies in temperate deciduous forest zones.

Below the temperate zones there are the sub-tropical forests of

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Europe, Central and West Africa, India, Asia, South Africa, Central and South America and Southern and Western Australia. Each has its own characteristic forest type designed to resist summer drought rather than winter cold. Long annual dry seasons cause the broad-leaved trees to conserve their water supply in tough, thick leathery, waxy-surfaced leaves, which are sharp and spiny.

Today, there is a new type of forest found in several parts of the world. Plantation forests are man-made forests which are beginning to play a significant role in global forest economy. At present, a little more than 100 million hectares of plantations exist worldwide. About forty percent of them produce fuelwood, with most of the remainder grown for pulp, wood and, to a lesser extent, lumber. With few exceptions, plantations are grown for commercial use and supply an increasing share of global timber production.

Over the past half century the earth’s vast green mantle of forests has been reduced to tattered remnants. As the world’s population has grown from 2.3 billion in 1950 to 6.3 billion today, some 3 billion hectares (ha) of the world’s original forest cover - nearly half - has been lost. The destruction continues: in each of the last dozen years, about 14.6 million hectares of forest - an area the size of Nepal - has been cut, bulldozed, or burned.

According to the FAO Global Forest Resources Assessment 2000, the net loss in forest area at the global level during the 1990s was an estimated 94 million ha - an area larger than Venezuela and equivalent to 2.4 per cent of the world’s total forests. This was a combination of an annual loss of 12.5 million ha of natural forests and an annual gain of 3.1 million ha in the form of forest plantations (see map below for details).

However, global statistics tend to obscure significant differences in forest cover change among regions and countries. Net deforestation rates were highest in West Africa and South America. This was followed by Asia, particularly in South-East Asia, though it was significantly offset by forest plantation establishment in other parts of the continent.

In contrast, the forest cover in the other regions, largely in industrialized temperate countries, increased slightly primarily as a result of natural forest succession on abandoned agricultural land. The countries with the highest loss of forest area between 1990 and 2000 include Brazil, Indonesia, Sudan, Zambia, Mexico and the Democratic Republic of Congo. Those with the highest net gain of forest area during this period were China, USA, Belarus, Kazakhstan and the Russian Federation.

In a 1997 study, the World Resources Institute coined the term «frontier forests» to describe forested areas that are relatively undisturbed by human activity and are large enough to maintain their original biodiversity, including viable populations of wide-ranging species.

According to this study, frontier forests constitute about 40 per cent of total global forest area, but are heavily concentrated in only

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