Перевод текста: Ecological Problems - Экологические проблемы. Топик по английскому языку "Ecological Problems - Экологические проблемы"

Ecological Problems

Since ancient times Nature has served Man, being the source of his life. For thousands of years people lived in harmony with environment and it seemed to them that natural riches were unlimited. But with the development of civilization man"s interference in nature began to increase.

Large cities with thousands of smoky industrial enterprises appear all over the world today. The by-products of their activity pollute the air we breathe, the water we drink, the land we grow grain and vegetables on.

Every year world industry pollutes the atmosphere with about 1000 million tons of dust and other harmful substances. Many cities suffer from smog. Vast forests are cut and burn in fire. Their disappearance upsets the oxygen balance. As a result some rare species of animals, birds, fish and plants disappear forever, a number of rivers and lakes dry up.

The pollution of air and the world"s ocean, destruction of the ozone layer is the result of man"s careless interaction with nature, a sign of the ecological crises.

The most horrible ecological disaster befell Ukraine and its people after the Chernobyl tragedy in April 1986. About 18 percent of the territory of Byelarus were also polluted with radioactive substances. A great damage has been done to the agriculture, forests and people"s health. The consequences of this explosion at the atomic power-station are tragic for the Ukrainian, Byelorussian and other nations.

Environmental protection is of a universal concern. That is why serious measures to create a system of ecological security should be taken.

Some progress has been already made in this direction. As many as 159 countries - members of the UNO - have set up environmental protection agencies. Numerous conferences have been held by these agencies to discuss problems facing ecologically poor regions including the Aral Sea, the South Urals, Kuzbass, Donbass, Semipalatinsk and Chernobyl.

An international environmental research centre has been set up on Lake Baikal. The international organisation Greenpeace is also doing much to preserve the environment.

But these are only the initial steps and they must be carried onward to protect nature, to save life on the planet not only for the sake of the present but also for the future generations.

Экологические проблемы

С древних времен природа служит человеку, являясь источником его жизни. Тысячи лет люди жили в гармонии с окружающей средой. И им казалось, что природные богатства неисчерпаемы. Но с развитием цивилизации человек все больше стал вмешиваться в природу.

Во всем мире появляются большие города с тысячами дымящих промышленных предприятий. Побочные продукты их деятельности загрязняют воздух, которым мы дышим, воду, которую мы пьем, землю, на которой мы выращиваем пшеницу и овощи.

Каждый год мировая промышленность вырабатывает один миллион тонн пыли и других вредных веществ. Многие города страдают от смога. Огромные леса вырубаются и сжигаются. Их исчезновение нарушает кислородный баланс. В результате некоторые редкие виды животных, птиц, рыб и растений навсегда исчезают. Высыхают многие реки и озера.

Загрязнение воздуха и мирового океана, разрушение озонового слоя являются результатом небрежного обращения с природой, признаком экологического кризиса.

Самая ужасная экологическая катастрофа постигла Украину и ее народ после чернобыльской трагедии в апреле 1986 г. Также около восемнадцати процентов территории Белоруссии было загрязнено радиоактивными веществами. Был нанесен большой урон сельскому хозяйству, лесам и здоровью людей. Последствия этого взрыва на атомной станции трагические для украинцев, белорусов и других наций.

Защита окружающей среды - всеобщая забота. Вот почему необходимо принять серьезные меры для разработки системы экологической безопасности.

В этом направлении уже достигнут определенный прогресс. 159 стран - членов ООН организовали агентства по защите окружающей среды. Этими агентствами были проведены многочисленные конференции, на которых обсуждались проблемы, стоящие перед экологически неблагополучными регионами, включая Аральское море, Южный Урал, Кузбасс, Донбасс, Семипалатинск и Чернобыль.

На озере Байкал был открыт международный центр ш> следований окружающей среды. Международная организация "Гринпис" делает многое для того, чтобы сохранить окружающую среду.

Но это всего лишь первые шаги, и надо двигаться вперед, защищая природу, сохраняя жизнь на планете, не только ради настоящего, но и для будущих поколений.

Questions:

1. How did people live for thousands of years?
2. What cities appear all over the world today?
3. What pollutes the air we breathe?
4. What is the result of the pollution the atmosphere?
5. Why is environmental protection of a universal concern?
6. What are the initial steps in this direction?

Vocabulary:

ancient - древний
harmony - гармония
environment - окружающая среда
riches - богатства
unlimited - неограниченный
to interfere - вмешиваться
to increase - увеличиваться, возрастать
smoky - дымный
enterprises - предприятия
by-product - побочный продукт
activity - деятельность
to pollute - загрязнять
substances - вещества
oxigen - кислород
rare - редкий
destruction - разрушение
ozone - озон
layer - слой
interaction - взаимодействие
horrible - ужасный
disaster - катастрофа
to befall - пасть (на что-то)

Ecological problems

Ecology is a scientific branch which studies interactions between organisms and their environment. It also studies the biodiversity of our planet. Earth is the only planet in the solar system where there is life. It is home to various kinds of plant and animal species. For centuries people lived in harmony with their environment until industrialization began. It brought human society into conflict with nature, which today has grown to a dramatic scale. Every year industrial waste pollutes surrounding atmosphere with millions of tons of dust and harmful substances.

The most acute problems include shortage of natural resources, global warming, acid rains, wildlife extinction, water and air pollution.

Air pollution is one of the most important and urgent problems. It is mostly caused by transport and factory fumes, which gradually destroy the ozone layer. Unfortunately, this can have dire consequences, as the ozone layer is there to protect our planet from sun radiation. Most aerosols which are used in daily life create large holes in this layer.

Water pollution also leads to numerous problems in natural environment. Many ships carry oil by sea. In case, there is a leakage, many fish die or get contaminated. It happens because their habitat gets polluted. People can also suffer if they eat such fish. Oil and other waste pollute beaches as well, which makes it difficult for holiday-makers to swim.

Acid rains lead to deforestation. Many forests disappear because of acid rains. It is especially true for tropical forests. Such rains kill nature in many ways: animals die out, climate changes along with ecosystem.

Wildlife extinction is no less acute. Many species of animals are in danger nowadays. For example, the blue whale, which is the largest water animal in the world, has been hunted for so long that it became a rare animal. The largest land animal is the African elephant, and it is also exposed to extinction. Even though they are strictly protected, these animals are still hunted for their valuable tusks. The only solution of this problem is wildlife conservation. It means opening more national parks, planting more new forests, and cutting down on industrial pollution.

Global warming has recently become a real threat. It is the rise in the average temperature of Earth’s atmosphere and oceans, which brings tangible changes into world’s climate. It is primarily a problem of too much carbon dioxide in the atmosphere. When we burn fossil fuels, such as coal or oil, carbon overloads and creates greenhouse effect.

Shortage of natural resources will definitely affect the future of our environment. It includes food and water shortage, fuel and non-fuel minerals shortage. These resources are not limitless and if people persist using them uncontrollably, the upcoming years will become extremely polluted, economically unstable and risky.

Экологические проблемы

Экология – это научное направление, которое изучает взаимодействие между организмами и окружающей их средой. Она также изучает биоразнообразия нашей планеты. Земля является единственной планетой в Солнечной системе, на которой есть жизнь. Она является местом обитания различных видов растений и животных. На протяжении многих веков люди жили в гармонии с окружающей средой, пока не началась индустриализация. Она привела человечество к конфликту с природой, который принял масштабные обороты. Ежегодно промышленные отходы загрязняют окружающую атмосферу миллионами тонн пыли и вредных веществ.

К наиболее острым проблемам относятся нехватка природных ресурсов, глобальное потепление, кислотные дожди, исчезновение диких животных, загрязнение воды и воздуха.

Загрязнение воздуха является одним из самых важных и актуальных проблем. Это в основном вызвано транспортным и заводским задымлением, которое постепенно разрушает озоновый слой. К сожалению, это может иметь тяжелые последствия, так как озоновый слой защищает нашу планету от солнечного излучения. Большинство аэрозолей, которые используются в повседневной жизни, создают большие дыры в этом слое.

Загрязнение воды также приводит к многочисленным проблемам в окружающей среде. Многие корабли транспортируют по морю нефть. В случае малейшей утечки, рыбы умирают или заражаются. Это происходит из-за загрязнений их среды обитания. Люди могут также пострадать, если будут употреблять в пищу такую рыбу. Нефть и прочие отходы загрязняют пляжи, что препятствует плаванию отдыхающих.

Кислотные дожди приводят к вырубке лесов. Многие леса исчезают из-за кислотных дождей. В частности это относится к тропическим лесам. Такие дожди убивают природу во многих отношениях: вымирают животные, изменяется климат наряду с экосистемой. ­

Исчезновение диких животных – не менее острая проблема. В настоящее время многие виды животных находятся в опасности. Например, на голубого кита, который является крупнейшим водным животным в мире, так долго охотились, что он стал редким животным. Крупнейшее сухопутное животное, африканский слон, также подвержен исчезновению. Даже если их строго охраняют, за этими животными все еще охотятся из-за их ценных бивней. Единственным решением этой проблемы является сохранение дикой природы. Сюда относятся открытие новых национальных парков, посадка новых лесов и сокращение промышленного загрязнения.

Глобальное потепление в последнее время стало реальной угрозой. Это повышение средней температуры атмосферы и океанов Земли, которое приводит к ощутимым изменениям в климате планеты. Эта проблема, прежде всего, связана с большим количеством двуокиси углерода в атмосфере. Когда мы сжигаем ископаемое топливо, например уголь или нефть, уровень углерода возрастает и создает парниковый эффект.

Нехватка природных ресурсов , безусловно, повлияет на будущее нашей окружающей среды. Это включает дефицит пищи и воды, топливных и не топливных полезных ископаемых. Такие ресурсы не безграничны, и если люди будут продолжать необдуманно тратить их, предстоящие годы будут чрезвычайно загрязненными, экономически нестабильными и рискованными.

M.N. Makeeva, L.P. Tsilenko, A.A. Gvozdeva MODERN ECOLOGICAL PROBLEMS TSTU Publishing House Министерство образования и науки Российской Федерации Тамбовский государственный технический университет М.Н. Макеева, Л.П. Циленко, А.А. Гвоздева СОВРЕМЕННЫЕ ЭКОЛОГИЧЕСКИЕ ПРОБЛЕМЫ Сборник текстов на английском языке для студентов неязыковых вузов Тамбов Издательство ТГТУ 2004 УДК 802.0(076) ББК Ш13(Ан)я923 С56 Рецензент Кандидат педагогических наук, доцент Т.Г. Бортникова С56 Современные экологические проблемы: Сборник текстов на английском языке / Авт.-сост.: М.Н. Макеева, Л.П. Циленко, А.А. Гвоздева. Тамбов: Изд-во Тамб. гос. техн. ун-та, 2004. 96 с. Данный сборник представляет собой книгу для чтения на английском языке для студентов не- языковых вузов. Предлагаемые аутентичные тексты отвечают динамике современного научно- технического прогресса, специфике изучаемых в университете специальностей, а также требовани- ям программы по английскому языку для студентов высших учебных заведений. УДК 802.0(076) ББК Ш13(Ан)я923 © Тамбовский государственный технический университет (ТГТУ), 2004 Учебное издание СОВРЕМЕННЫЕ ЭКОЛОГИЧЕСКИЕ ПРОБЛЕМЫ Сборник текстов на английском языке Авторы-составители: Макеева Марина Николаевна, Циленко Любовь Петровна, Гвоздева Анна Анатольевна Редактор Т.М. Глинкина Компьютерное макетирование Е.В. Кораблевой Подписано в печать 18.06.04 Формат 60 × 84 / 16. Бумага офсетная. Печать офсетная Гарнитура Тimes New Roman. Объем: 5,58 усл. печ. л.; 5,5 уч.-изд. л. Тираж 80 экз. С. 440M Издательско-полиграфический центр Тамбовского государственного технического университета, 392000, Тамбов, Советская, 106, к. 14 ECOLOGY Ecology is the study of the relationship of plants and animals with their physical and biological environ- ment. The physical environment includes light and heat or solar radiation, moisture, wind, oxygen, carbon diox- ide, nutrients in soil, water, and atmosphere. The biological environment includes organisms of the same kind as well as other plants and animals. Because of the diverse approaches required to study organisms in their environment, ecology draws upon such fields as climatology, hydrology, oceanography, physics, chemistry, geology, and soil analysis. To study the relationships between organisms, ecology also involves such disparate sciences as animal behavior, taxon- omy, physiology, and mathematics. An increased public awareness of environmental problems has made ecology a common but often misused word. It is confused with environmental programs and environmental science. Although the field is a distinct scientific discipline, ecology does indeed contribute to the study and understanding of environmental problems. The term "ecology" was introduced by the German biologist Ernst Heinrich Haeckel in 1866; it is derived from the Greek "oikos" ("household"), sharing the same root word as "economics". Thus, the term implies the study of the economy of nature. Modern ecology, in part, began with Charles Darwin. In developing his theory of evolution, Darwin stressed the adaptation of organisms to their environment through natural selection. Also making important contributions were plant geographers, such as Alexander von Humboldt, who were deeply interested in the "how" and "why" of vegetation distribution around the world. The thin mantle of life that covers the earth is called the biosphere. Several approaches are used to classify its regions. BIOMES The broad units of vegetation are called "plant formations" by European ecologists and "biomes" by North American ecologists. The major difference between the two terms is that "biomes" include associated animal life. Major biomes, however, go by the name of the dominant forms of plant life. Influenced by latitude, elevation, and associated moisture and temperature regimes, terrestrial biomes vary geographically from the tropics through the arctic and include various types of forest, grassland, shrub land, and desert. These biomes also include their associated freshwater communities: streams, lakes, ponds, and wetlands. Marine environments, also considered biomes by some ecologists, comprise the open ocean, littoral (shallow water) regions, benthic (bottom) regions, rocky shores, sandy shores, estuaries, and associated tidal marshes. ECOSYSTEMS A more useful way of looking at the terrestrial and aquatic landscapes is to view them as ecosystems, a word coined in 1935 by the British plant ecologist Sir Arthur George Tansley to stress the concept of each lo- cale or habitat as an integrated whole. A system is a collection of interdependent parts that function as a unit and involve inputs and outputs. The major parts of an ecosystem are the producers (green plants), the consum- ers (herbivores and carnivores), the decomposers (fungi and bacteria), and the nonliving, or abiotic, compo- nents, consisting of dead organic matter and nutrients in the soil and water. Inputs into the ecosystem are solar energy, water, oxygen, carbon dioxide, nitrogen, and other elements and compounds. Outputs from the ecosys- tem include water, oxygen, carbon dioxide, nutrient losses, and the heat released in cellular respiration, or heat of respiration. The major driving force is solar energy. ENERGY AND NUTRIENTS Ecosystems function with energy flowing in one direction from the sun, and through nutrients, which are continuously recycled. Light energy is used by plants, which, by the process of photosynthesis, convert it to chemical energy in the form of carbohydrates and other carbon compounds. This energy is then transferred through the ecosystem by a series of steps that involve eating and being eaten, or what is called a food web. Each step in the transfer of energy involves several trophic, or feeding, levels: plants, herbivores (plant eaters), two or three levels of carnivores (meat eaters), and decomposers. Only a fraction of the energy fixed by plants follows this pathway, known as the grazing food web. Plant and animal matter not used in the grazing food chain, such as fallen leaves, twigs, roots, tree trunks, and the dead bodies of animals, support the decomposer food web. Bacteria, fungi, and animals that feed on dead material become the energy source for higher trophic levels that tie into the grazing food web. In this way, nature makes maximum use of energy originally fixed by plants. The number of trophic levels is limited in both types of food webs, because at each transfer a great deal of energy is lost (such as heat of respiration) and is no longer usable or transferable to the next trophic level. Thus, each trophic level contains less energy than the trophic level supporting it. For this reason, as an example, deer or caribou (herbivores) are more abundant than wolves (carnivores). Energy flow fuels the biogeochemical, or nutrient, cycles. The cycling of nutrients begins with their release from organic matter by weathering and decomposition in a form that can be picked up by plants. Plants in- corporate nutrients available in soil and water and store them in their tissues. The nutrients are transferred from one trophic level to another through the food web. Because most plants and animals go uneaten, nutri- ents contained in their tissues, after passing through the decomposer food web, are ultimately released by bacterial and fungal decomposition, a process that reduces complex organic compounds into simple inor- ganic compounds available for reuse by plants. IMBALANCES Within an ecosystem, nutrients are cycled internally. But there are leakages or outputs, and these must be balanced by inputs, or the ecosystem will fail to function. Nutrient inputs to the system come from weathering of rocks, from windblown dust, and from precipitation, which can carry material great distances. Varying quan- tities of nutrients are carried from terrestrial ecosystems by the movement of water and deposited in aquatic ecosystems and associated lowlands. Erosion and the harvesting of timber and crops remove considerable quan- tities of nutrients that must be replaced. The failure to do so results in an impoverishment of the ecosystem. This is why agricultural lands must be fertilized. If inputs of any nutrient greatly exceed outputs, the nutrient cycle in the ecosystem becomes stressed or overloaded, resulting in pollution. Pollution can be considered an input of nutrients exceeding the capability of the ecosystem to process them. Nutrients eroded and leached from agricultural lands, along with sewage and industrial wastes accumulated from urban areas, all drain into streams, rivers, lakes, and estuaries. These pollut- ants destroy plants and animals that cannot tolerate their presence or the changed environmental conditions caused by them; at the same time, they favor a few organisms more tolerant to changed conditions. Thus, pre- cipitation filled with sulfur dioxide and oxides of nitrogen from industrial areas converts to weak sulfuric and nitric acids, known as acid rain, and falls on large areas of terrestrial and aquatic ecosystems. This upsets acid- base relations in some ecosystems, killing fish and aquatic invertebrates, and increasing soil acidity, which re- duces forest growth in northern and other ecosystems that lack limestone to neutralize the acid. POPULATIONS AND COMMUNITIES The functional units of an ecosystem are the populations of organisms through which energy and nutrients move. A population is a group of interbreeding organisms of the same kind living in the same place at the same time. Groups of populations within an ecosystem interact in various ways. These interdependent populations of plants and animals make up the community, which encompasses the biotic portion of the ecosystem. DIVERSITY The community has certain attributes, among them dominance and species diversity. Dominance results when one or several species control the environmental conditions that influence associated species. In a forest, for example, the dominant species may be one or more species of trees, such as oak or spruce; in a marine community, the dominant organisms frequently are animals such as mussels or oysters. Dominance can influ- ence diversity of species in a community because diversity involves not only the number of species in a com- munity, but also how numbers of individual species are apportioned. The physical nature of a community is evidenced by layering, or stratification. In terrestrial communities, stratification is influenced by the growth form of the plants. Simple communities such as grasslands, with little vertical stratification, usually consist of two layers, the ground layer and the herbaceous layer. A forest has up to six layers: ground, herbaceous, low shrub, low tree and high shrub, lower canopy, and upper canopy. These strata influence the physical environment and diversity of habitats for wildlife. Vertical stratification of life in aquatic communities, by contrast, is influenced mostly by physical conditions: depth, light, temperature, pres- sure, salinity, oxygen, and carbon dioxide. HABITAT AND NICHE The community provides the habitat – the place where particular plants or animals live. Within the habitat, organisms occupy different niches. A niche is the functional role of a species in a community – that is, its occupation, or how it earns its living. For example, the scarlet tanager lives in a deciduous forest habitat. Its niche, in part, is gleaning insects from the canopy foliage. The more a community is stratified, the more finely the habitat is divided into additional niches. ENVIRONMENT Environment comprises all of the external factors affecting an organism. These factors may be other living organisms (biotic factors) or nonliving variables (abiotic factors), such as temperature, rainfall, day length, wind, and ocean currents. The interactions of organisms with biotic and abiotic factors form an ecosystem. Even minute changes in any one factor in an ecosystem can influence whether or not a particular plant or ani- mal species will be successful in its environment. Organisms and their environment constantly interact, and both are changed by this interaction. Like all other living creatures, humans have clearly changed their environment, but they have done so generally on a grander scale than have all other species. Some of these human-induced changes – such as the destruction of the world’s tropical rain forests to create farms or grazing land for cattle – have led to altered climate patterns. In turn, altered climate patterns have changed the way animals and plants are distributed in different ecosystems. Scientists study the long-term consequences of human actions on the environment, while environmental- ists-professionals in various fields, as well as concerned citizens-advocate ways to lessen the impact of human activity on the natural world. UNDERSTANDING THE ENVIRONMENT The science of ecology attempts to explain why plants and animals live where they do and why their popu- lations are the sizes they are. Understanding the distribution and population size of organisms helps scientists evaluate the health of the environment. In 1840 German chemist, Justus von Liebig first proposed that populations could not grow indefinitely, a basic principle now known as the Law of the Minimum. Biotic and abiotic factors, singly or in combination, ultimately limit the size that any population may attain. This size limit, known as a population’s carrying capac- ity, occurs when needed resources, such as food, breeding sites, and water, are in short supply. For example, the amount of nutrients in soil influences the amount of wheat that grows on a farm. If just one soil nutrient, such as nitrogen, is missing or below optimal levels, fewer healthy wheat plants will grow. Either population size or distribution may also be affected, directly or indirectly, by the way species in an ecosystem interact with one another. In an experiment performed in the late 1960s in the rocky tidal zone along the Pacific Coast of the United States, American ecologist Robert Paine studied an area that contained 15 spe- cies of invertebrates, including starfish, mussels, limpets, barnacles, and chitons. Paine found that in this eco- system one species of starfish preyed heavily on a species of mussel, preventing that mussel population from multiplying and monopolizing space in the tidal zone. When Paine removed the starfish from the area, he found that the mussel population quickly increased in size, crowding out most other organisms from rock surfaces. The number of invertebrate species in the ecosystem soon dropped to eight species. Paine concluded that the loss of just one species, the starfish, indirectly led to the loss of an additional six species and a transformation of the ecosystem. Typically, the species that coexist in ecosystems have evolved together for many generations. These popula- tions have established balanced interactions with each other that enable all populations in the area to remain relatively stable. Occasionally, however, natural or human-made disruptions occur that have unforeseen con- sequences to populations in an ecosystem. For example, 17th-century sailors routinely introduced goats to isolated oceanic islands, intending for the goats to roam freely and serve as a source of meat when the sailors returned to the islands during future voyages. As non-native species free from all natural predators, the goats thrived and, in the process, overgrazed many of the islands. With a change in plant composition, many of the native animal species on the islands were driven to extinction. A simple action, the introduction of goats to an island, yielded many changes in the island ecosystem, demonstrating that all members of a community are closely interconnected. To better understand the impact of natural and human disruptions on the Earth, in 1991, the National Aero- nautics and Space Administration (NASA) began to use artificial satellites to study global change. NASA’s un- dertaking, called Earth Science Enterprise, and is a part of an international effort linking numerous satellites into a single Earth Observing System (EOS). EOS collects information about the interactions occurring in the atmosphere, on land, and in the oceans, and these data help scientists and lawmakers make sound environ- mental policy decisions. FACTORS THREATENING THE ENVIRONMENT The problems facing the environment are vast and diverse. Global warming, the depletion of the ozone layer in the atmosphere, and destruction of the world’s rain forests are just some of the problems that many sci- entists believe will reach critical proportions in the coming decades. All of these problems will be directly af- fected by the size of the human population. POPULATION GROWTH Human population growth is at the root of virtually all of the world’s environmental problems. Although the growth rate of the world’s population has slowed slightly since the 1990s, the world’s population increases by about 77 million human beings each year. As the number of people increases, crowding generates pollution, destroys more habitats, and uses up additional natural resources. The Population Division of the United Nations (UN) predicts that the world’s population will increase from 6.23 billion people in 2000 to 9.3 billion people in 2050. The UN estimates that the population will stabilize at more than 11 billion in 2200. Other experts predict that numbers will continue to rise into the foreseeable fu- ture, to as many as 19 billion people by the year 2200. Although rates of population increase are now much slower in the developed world than in the developing world, it would be a mistake to assume that population growth is primarily a problem of developing countries. In fact, because larger amounts of resources per person are used in developed nations, each individual from the developed world has a much greater environmental impact than does a person from a developing country. Con- servation strategies that would not significantly alter lifestyles but that would greatly lessen environmental im- pact are essential in the developed world. In the developing world, meanwhile, the most important factors necessary to lower population growth rates are democracy and social justice. Studies show that population growth rates have fallen in developing areas where several social conditions exist. In these areas, literacy rates have increased and women receive economic status equal to that of men, enabling women to hold jobs and own property. In addition, birth control informa- tion in these areas is more widely available, and women are free to make their own reproductive decisions. GLOBAL WARMING Like the glass panes in a greenhouse, certain gases in the Earth’s atmosphere permit the Sun’s radiation to heat Earth. At the same time, these gases retard the escape into space of the infrared energy radiated back out by Earth. This process is referred to as the greenhouse effect. These gases, primarily carbon dioxide, methane, nitrous oxide, and water vapor, insulate Earth’s surface, helping to maintain warm temperatures. Without these gases, Earth would be a frozen planet with an average temperature of about –18 °C (about 0 °F) instead of a comfortable 15 °C (59 °F). If the concentration of these gases rises, they trap more heat within the atmosphere, causing worldwide temperatures to rise. Within the last century, the amount of carbon dioxide in the atmosphere has increased dramatically, largely because people burn vast amounts of fossil fuels – coal and petroleum and its derivatives. Average global tem- perature also has increased – by about 0.6 Celsius degrees (1 Fahrenheit degree) within the past century. At- mospheric scientists have found that at least half of that temperature increase can be attributed to human activ- ity. They predict that unless dramatic action is taken, global temperature will continue to rise by 1.4 to 5.8 Cel- sius degrees (2.5 to 10.4 Fahrenheit degrees) over the next century. Although such an increase may not seem like a great difference, during the last ice age the global temperature was only 2.2 Celsius degrees (4 Fahrenheit degrees) cooler than it is presently. The consequences of such a modest increase in temperature may be devastating. Already scientists have de- tected a 40 percent reduction in the average thickness of Arctic ice. Other problems that may develop include a rise in sea levels that will completely inundate a number of low-lying island nations and flood many coastal cities, such as New York and Miami. Many plant and animal species will probably be driven into ex- tinction, agriculture will be severely disrupted in many regions, and the frequency of severe hurricanes and droughts will likely increase. DEPLETION OF THE OZONE LAYER The ozone layer, a thin band in the stratosphere (layer of the upper atmosphere), serves to shield Earth from the Sun’s harmful ultraviolet rays. In the 1970s, scientists discovered that chlorofluorocarbons (CFCs)- chemicals used in refrigeration, air-conditioning systems, cleaning solvents, and aerosol sprays-destroy the ozone layer. CFCs release chlorine into the atmosphere; chlorine, in turn, breaks down ozone molecules. Be- cause chlorine is not affected by its interaction with ozone, each chlorine molecule has the ability to destroy a large amount of ozone for an extended period of time. The consequences of continued depletion of the ozone layer would be dramatic. Increased ultraviolet radia- tion would lead to a growing number of skin cancers and cataracts and also reduce the ability of immune sys- tems to respond to infection. Additionally, growth of the world’s oceanic plankton, the base of most marine food chains, would decline. Plankton contains photosynthetic organisms that break down carbon dioxide. If plankton populations decline, it may lead to increased carbon dioxide levels in the atmosphere and thus to global warming. Recent studies suggest that global warming, in turn, may increase the amount of ozone de- stroyed. Even if the manufacture of CFCs is immediately banned, the chlorine already released into the atmos- phere will continue to destroy the ozone layer for many decades. In 1987, an international pact called the Montreal Protocol on Substances that Deplete the Ozone Layer set specific targets for all nations to achieve in order to reduce emissions of chemicals responsible for the destruc- tion of the ozone layer. Many people had hoped that this treaty would cause ozone loss to peak and begin to de- cline by the year 2000. In fact, in the fall of 2000, the hole in the ozone layer over Antarctica was the largest ever recorded. The hole the following year was slightly smaller, leading some to believe that the depletion of ozone had stabilized. Even if the most stringent prohibitions against CFCs are implemented, however, scientists expect that it will take at least 50 more years for the hole over Antarctica to close completely. HABITAT DESTRUCTION AND SPECIES EXTINCTION Plant and animal species are dying out at an unprecedented rate. Estimates range that from 4,000 to as many as 50,000 species per year become extinct. The leading cause of extinction is habitat destruction, particu- larly of the world’s richest ecosystems-tropical rain forests and coral reefs. If the world’s rain forests continue to be cut down at the current rate, they may completely disappear by the year 2030. In addition, if the world’s population continues to grow at its present rate and puts even more pressure on these habitats, they might well be destroyed sooner. AIR POLLUTION A significant portion of industry and transportation burns fossil fuels, such as gasoline. When these fuels burn, chemicals and particulate matter are released into the atmosphere. Although a vast number of substances contribute to air pollution, the most common air pollutants contain carbon, sulfur, and nitrogen. These chemi- cals interact with one another and with ultraviolet radiation in sunlight in dangerous ways. Smog, usually found in urban areas with large numbers of automobiles, forms when nitrogen oxides react with hydrocarbons in the air to produce aldehydes and ketones. Smog can cause serious health problems. Acid rain forms when sulfur dioxide and nitrous oxide transform into sulfuric acid and nitric acid in the atmosphere and come back to Earth in precipitation. Acid rain has made numerous lakes so acidic that they no longer support fish populations. Acid rain is also responsible for the decline of many forest ecosystems world- wide, including Germany’s Black Forest and forests throughout the eastern United States. WATER POLLUTION Estimates suggest that nearly 1.5 billion people worldwide lack safe drinking water and that at least 5 mil- lion deaths per year can be attributed to waterborne diseases. Water pollution may come from point sources or nonpoint sources. Point sources discharge pollutants from specific locations, such as factories, sewage treat- ment plants, and oil tankers. The technology exists to monitor and regulate point sources of pollution, although in some areas this occurs only sporadically. Pollution from nonpoint sources occurs when rainfall or snowmelt moves over and through the ground. As the runoff moves, it picks up and carries away pollutants, such as pesti- cides and fertilizers, depositing the pollutants into lakes, rivers, wetlands, coastal waters, and even underground sources of drinking water. Pollution arising from nonpoint sources accounts for a majority of the contaminants in streams and lakes. With almost 80 percent of the planet covered by oceans, people have long acted as if those bodies of water could serve as a limitless dumping ground for wastes. However, raw sewage, garbage, and oil spills have begun to overwhelm the diluting capabilities of the oceans, and most coastal waters are now polluted, threatening ma- rine wildlife. Beaches around the world close regularly, often because the surrounding waters contain high lev- els of bacteria from sewage disposal. HOW ECOSYSTEMS WORK. ECOSYSTEM MANAGEMENT Ecosystem comprises organisms living in a particular environment, such as a forest or a coral reef, and the physical parts of the environment that affect them. The term ecosystem was coined in 1935 by the British ecologist Sir Arthur George Tansley, who described natural systems in "constant interchange" among their liv- ing and nonliving parts. The ecosystem concept fits into an ordered view of nature that was developed by scientists to simplify the study of the relationships between organisms and their physical environment, a field known as ecology. At the top of the hierarchy is the planet’s entire living environment, known as the biosphere. Within this biosphere are several large categories of living communities known as biomes that are usually characterized by their domi- nant vegetation, such as grasslands, tropical forests, or deserts. The biomes are in turn made up of ecosystems. The living, or biotic, parts of an ecosystem, such as the plants, animals, and bacteria found in soil, are known as a community. The physical surroundings, or abiotic components, such as the minerals found in the soil, are known as the environment or habitat. Any given place may have several different ecosystems that vary in size and complexity. A tropical island, for example, may have a rain forest ecosystem that covers hundreds of square miles, a mangrove swamp eco- system along the coast, and an underwater coral reef ecosystem. No matter how the size or complexity of an ecosystem is characterized, all ecosystems exhibit a constant exchange of matter and energy between the biotic and abiotic community. Ecosystem components are so interconnected that a change in any one component of an ecosystem will cause subsequent changes throughout the system. The living portion of an ecosystem is best described in terms of feeding levels known as trophic levels. Green plants make up the first trophic level and are known as primary producers. Plants are able to convert en- ergy from the sun into food in a process known as photosynthesis. In the second trophic level, the primary con- sumers – known as herbivores – are animals and insects that obtain their energy solely by eating the green plants. The third trophic level is composed of the secondary consumers, flesh-eating or carnivorous animals that feed on herbivores. At the fourth level are the tertiary consumers, carnivores that feed on other carnivores. Fi- nally, the fifth trophic level consists of the decomposers, organisms such as fungi and bacteria that break down dead or dying matter into nutrients that can be used again. Some or all of these trophic levels combine to form what is known as a food web, the ecosystem’s mecha- nism for circulating and recycling energy and materials. For example, in an aquatic ecosystem algae and other aquatic plants use sunlight to produce energy in the form of carbohydrates. Primary consumers such as insects and small fish may feed on some of this plant matter, and are in turn eaten by secondary consumers, such as salmon. A brown bear may play the role of the tertiary consumer by catching and eating salmon. Bacteria and fungi may then feed upon and decompose the salmon carcass left behind by the bear, enabling the valuable nonliving components of the ecosystem, such as chemical nutrients, to leach back into the soil and water, where they can be absorbed by the roots of plants. In this way, nutrients and the energy that green plants derive from sunlight are efficiently transferred and recycled throughout the ecosystem. In addition to the exchange of energy, ecosystems are characterized by several other cycles. Elements such as carbon and nitrogen travel throughout the biotic and abiotic components of an ecosystem in processes known as nutrient cycles. For example, nitrogen traveling in the air may be snatched by tree-dwelling, or epiphytic, lichen that converts it to a form useful to plants. When rain drips through the lichen and falls to the ground, or the lichen itself falls to the forest floor, the nitrogen from the raindrops or the lichen is leached into the soil to be used by plants and trees. Another process important to ecosystems is the water cycle, the movement of water from ocean to atmosphere, to land and eventually back to the ocean. An ecosystem such as a forest or wetland plays a significant role in this cycle by storing, releasing, or filtering the water as it passes through the system. Every ecosystem is also characterized by a disturbance cycle, a regular cycle of events such as fires, storms, floods, and landslides that keeps the ecosystem in a constant state of change and adaptation. Some spe- cies even depend on the disturbance cycle for survival or reproduction. For example, longleaf pine forests de- pend on frequent low-intensity fires for reproduction. The cones of the trees, which contain the reproductive structures, are sealed shut with a resin that melts away to release the seeds only under high heat. ECOSYSTEM MANAGEMENT Humans benefit from these smooth-functioning ecosystems in many ways. Healthy forests, streams, and wetlands contribute to clean air and clean water by trapping fast-moving air and water, enabling impurities to settle out or be converted to harmless compounds by plants or soil. The diversity of organisms, or biodiversity, in an ecosystem provides essential foods, medicines, and other materials. But as human populations increase and their encroachment on natural habitats expand, humans are having detrimental effects on the very ecosys- tems on which they depend. The survival of natural ecosystems around the world is threatened by many human activities: bulldozing wetlands and clear-cutting forests – the systematic cutting of all trees in a specific area – to make room for new housing and agricultural land; damming rivers to harness the energy for electricity and water for irrigation; and polluting the air, soil, and water. Many organizations and government agencies have adopted a new approach to managing natural resources – naturally occurring materials that have economic or cultural value, such as commercial fisheries, timber, and water, in order to prevent their catastrophic depletion. This strategy, known as ecosystem management, treats resources as interdependent ecosystems rather than simply commodities to be extracted. Using advances in the study of ecology to protect the biodiversity of an ecosystem, ecosystem management encourages prac- tices that enable humans to obtain necessary resources using methods that protect the whole ecosystem. Be- cause regional economic prosperity may be linked to ecosystem health, the needs of the human community are also considered. Ecosystem management often requires special measures to protect threatened or endangered species that play key roles in the ecosystem. In the commercial shrimp trawling industry, for example, ecosystem manage- ment techniques protect loggerhead sea turtles. In the last thirty years, populations of loggerhead turtles on the southeastern coasts of the United States have been declining at alarming rates due to beach development and the ensuing erosion, bright lights, and traffic, which make it nearly impossible for female turtles to build nests on beaches. At sea, loggerheads are threatened by oil spills and plastic debris, offshore dredging, injury from boat propellers, and being caught in fishing nets and equipment. In 1970, the species was listed as threatened under the Endangered Species Act. When scientists learned that commercial shrimp trawling nets were trapping and killing between 5000 and 50,000 loggerhead sea turtles a year, they developed a large metal grid called a Turtle Excluder Device (TED) that fits into the trawl net, preventing 97 percent of trawl-related loggerhead turtle deaths while only minimally

In recent years the number of environmental problems has increased greatly. One of the most dangerous problems for our planet is global warming which means that most climates all over the world are changing and getting warmer. It happens because we burn too much petrol resources, such as oil and coal, and the Earth heats up. This process can cause melting of the polar ice and the sea level rising in the future. If the climate changes there will be floods, heavy storms or severe droughts in different areas of the world. Cutting down on exhaust fumes from vehicles could help solve this serious problem.

Our planet is overpopulated, that’s why we are using up our natural resources – they are not endless. So the scientists have started looking for some alternate forms of energy such as water, wind, sunlight and even tides. These resources are clean, natural and unlimited. I’m glad that modern automobile industries make hybrids which use electric or solar energy instead of petrol. It would definitely help protect our environment from pollution.

There are different kinds of environmental pollution: air pollution, water pollution, land pollution. Sadly, not all human beings realize or admit that we are the ones who cause these problems and we should be the first to stop them and protect our environment. Because of the industrial revolution the air is polluted with awful chemicals; seas and oceans are poisoned with oil spills. Many rare species of flora and fauna are threatened with extinction.

We should be proud to live on our wonderful planet and understand that the consequences of pollution might be terrible and affect us and our children later. We should start recycling things made of glass, paper, plastic and aluminium. We should stop smoking and plant as many trees as we can because they can give us more oxygen. We need to drive less and use public transport in order to reduce fuel burning. We are responsible for the situation.

Проблемы окружающей среды

В последние годы число проблем окружающей среды сильно возросло. Одной из самых опасных проблем для нашей планеты является глобальное потепление, которое означает изменение климата по всему миру и его потепление. Это происходит оттого, что мы сжигаем слишком много топливных ресурсов, таких как нефть и уголь, и Земля нагревается. Этот процесс может привести к таянию полярного льда и повышению уровня моря в будущем. Если изменится климат, произойдут наводнения, сильные штормы или жестокие засухи в разных частях света. Сокращение выхлопных газов транспортных средств могло бы способствовать разрешению этой серьезной проблемы.

Наша планета перенаселена, поэтому мы расходуем до предела наши природные ресурсы – они не бесконечны. Так ученые приступили к поискам альтернативных форм энергии, таких как вода, ветер, солнечный свет и даже приливы. Эти источники чисты, естественны и бесконечны. Я рад, что современная автомобильная промышленность выпускает гибриды, использующие электрическую или солнечную энергию вместо бензина. Это обязательно поможет защите нашей среды от загрязнения.

Существуют разные виды загрязнения окружающей среды: загрязнение воздуха, воды и почвы. К сожалению, не все люди осознают или признают, что именно мы создаем эти проблемы, и мы должны быть первыми, кто остановит их и защитит наше окружение. Из-за промышленной революции воздух загрязнен ужасными химикатами; моря и океаны отравлены разливами нефти. Многие редкие виды флоры и фауны находятся под угрозой вымирания.

Нам нужно гордиться тем, что мы живем на нашей замечательной планете, и следует понимать, что последствия загрязнения могут быть страшными и воздействовать на нас и наших детей позже. Нам нужно перерабатывать изделия из стекла, бумаги, пластика и алюминия. Нужно бросать курить и сажать как можно больше деревьев для того, чтобы они вырабатывали для нас больше кислорода. Мы должны меньше водить машины и стараться пользоваться общественным транспортом, чтобы снизить количество сжигаемого топлива. Мы ответственны за ситуацию.

We live on the earth. It is very, very big. There is a lot of water on the earth. It is in rivers, lakes, seas and oceans. There are a lot of forests and fields, hills and mountains on it. The earth is full of wonders. Different animals live on the earth. Different plants grow on it. The earth is beautiful. There are large countries and small countries. There are warm countries and cold countries. There are some countries where there are four seasons in a year and some countries where there are only two. When the sun shines it is day. When the sun does not shine it is night. When it is day in one country it is night in another. You can see the moon and the stars in the sky at night. People live in different countries. They speak different languages.

People have lived on our planet for many years. They lived and live on different continents, in different countries. People depend on their planet, on the sun, on animals and plants around them. People must take care of Earth. Our ecology becomes worse and worse with every new day. Many species of animals and birds are disappearing nowadays. People destruct wildlife, cut down trees to make furniture. They forget that people can"t live without trees and plants, because they fill air with oxygen. And, of course, great problems are population and animals destruction. The main reason of pollution is rubbish. Most of our rubbish goes to big holes in the ground, called "dumps". But dumps are very dangerous for our life "cause they are full of rats, which can carry infections away from dumps. Another way to get rid of rubbish is to burn it. But the fires make poisons, which go into the air and pollute it. But pollution isn"t the only actual problem. Every day a big number of animals disappears . People kill animals for different aims: e.g. people hunt whales for their meat and oil; elephants for their tusks, crocodiles for their leather and so on. And also animals are used for medical experiments. The most wide – speared from such animals are monkeys. Modern life is bad for animals, birds, fish. The air isn"t fresh and the water isn"t pure. They don"t have good meal and facilities for the life. You can find their names in the Red Book.

The planet Earth is only a tiny part of the universe, but it"s the only place where human beings can live. Today, our planet is in serious danger. Acid rains, global warming, air and water pollution, overpopulation are the problems that threaten human life on Earth.

Who is to blame for the disaster? The answer is simple: all of us. Our forests are disappearing because they are cut down or burnt. If this trend continues, one day we won"t have enough oxygen to breathe.

The seas are in danger. They are filled with poison: industrial and nuclear waste, chemical fertilisers and pesticides. The Mediterranean is already nearly dead; the North Sea is following. The Aral Sea is on the brink of extinction. If nothing is done about it, one day nothing will be able to live in the seas.Every ten minutes one kind of animal, plant or insect dies out for ever. If nothing is done about it, one million species that are alive today may soon become extinct.

Air pollution is another serious problem. In Cairo just breathing the air is dangerous - equivalent to smoking two packs of cigarettes a day. The same holds true for many Russian cities. Factories emit tons of harmful chemicals. These emissions have disastrous consequences for our planet. They are the main reason for the greenhouse effect and acid rains. An even greater threat are nuclear power stations. We all know how tragic the consequences of the Chernobyl disaster are.

Fortunately, it"s not too late to solve these problems. We have the time, the money and even the technology to make our planet a better, cleaner and safer place. We can plant trees and create parks for endangered species. We can recycle litter. We can support green parties and put pressure on those in power. Together we can save the planet and all of us with it.

Of course, people can"t stay indifferent to these problems. There are a lot of special organizations, which try to save our nature. The most known are: The Royal Society for the prevention of cruelty to animals (The RSPCA), the World Wildlife Fund (WWF) and Greenpeace. The RSPCA tries to protect animals from bad use. It operates big nation campaigns aimed at lost pets, circus animals. The WWF rescued several species of animals, mammals as well as birds. These organization also helped to create more than 250 National parks. Greenpeace began its work 20 years ago from saving whales. And now Greenpeace is a world-famous organization, which saves plants, animals and people. These organization, want to rescue animals, to help them to survive and to save jungle rain forests, which are in danger of destruction. And they also help animals "cause many of them have already gone as they have nowhere to live. Their homes, the trees, have disappeared. We must save wild animals. And we must find the right way to save land, people and animals. We must lake care of nature, because we are part of it.

I would advise everyone to think about this problem. Together we can find a solution!