Foreign Language University Training
Ecology (also known as Oekologie or Okology, from Greek:
"household" and "knowledge") is the scientific study of systems of living organisms and the interactions among organisms and between the organisms and their environment. The environment of an organism includes both physical properties, which can be described as the sum of local abiotic factors such as insolation (sunlight), climate, and geology, and biotic factors, which are other organisms that share its habitat.
The word "ecology" is often used more loosely in such terms as social ecology and deep ecology and in common parlance as a synonym for the natural environment or environmentalism. Likewise "ecologic" or ''ecological" is often taken in the sense of environmentally friendly. The term ecology or oekologie was coined by the German biologist Ernst Haeckel in 1866, when he defined it as "the comprehensive science of the relationship of the organism to the environment" Haeckel did not elaborate on the concept, and the first significant textbook on the subject (together with the first university course) was written by the Danish botanist, Eugenius Warming. For this early work, Warming is often identified as the founder of ecology.
Ecology is usually considered a branch of biology, the general science that studies living organisms. Organisms can be studied at man different levels from proteins and nucleic acids (in biochemistry and molecular biology) to cells (in cellular biology), to individuals (in botany, zoology, and other similar disciplines), and finally at the level of populations, communities, and ecosystems;, to the biosphere as a whole; these latter strata are the primary subjects of ecological inquiry. Ecology is a multi-disciplinary science. Because of its focus on the higher levels of the organization of life on earth and on the interrelation between organisms and their environment, ecology draws heavily on many other branches of science, especially geology and geography, meteorology, pedology genetics, chemistry, and physics. Thus, ecology is considered by some to be a holistic science, one that over-arches older disciplines such as biology which in this view become sub-disciplines contributing to ecological knowledge. In support of viewing ecology as a subject in its own right as opposed to a sub- discipline of biology, Robert Ulanowicz stated that "The emerging picture of ecosystem behavior does not resemble the worldview imparted by an extrapolation of conceptual trends established in other sciences."
Agriculture, fisheries, forestry, medicine and urban development are among human activities that would fall within Krebs' explanation of his definition of ecology: where organisms are found, how many occur there, and why.
As a scientific discipline, ecology does not dictate what is right or wrong However, ecological knowledge such as the quantification of biodiversity and population dynamics have provided a scientific basis for expressing the aims of environmentailsm and evaluating its goals and policies. Additionally, a holistic view of nature is stressed in both ecology and environmentalism.
Unit 11 Branches of Ecology. Part 1
Introduction
Read the text title and hypothesize what the text is about. Write down your hypothesis.
What do you know concerning this issue? List your ideas in the table left column “I know”. I know that... I have learnt that...
If you know answers to these questions write them down in the space given after each question.
Who was a founder of ecology? | |
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How do you understand the subject of ecology? | |
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What factors determine environment of an organism? | |
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Is ecology a multidisciplinary science? | |
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What branches of science does ecology comprise? | |
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Are “ecology” and “environmentalism” synonyms? | |
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When was the term “ecology” coined? | |
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4 Circle in the list the words and expressions you know. Write down their translation in the ble and calculate the percentage of your lexical competence.
common parlance |
| queen bee |
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protein |
| pollination |
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cell |
| multiple |
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community |
| interdisciplinary |
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pedology |
| biotic |
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holistic |
| abiotic |
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behavior |
| interaction |
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species |
| elaborate |
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Module: professional communication
Consider the ways an ecologist might approach studying the life of honeybees:
-The behavioral relationship between individuals of a species is behavioral ecology — for example, the study of the queen bee, and how she relates to the worker bees and the drones.
-The organized activity of a species is community ecology; for example, the activity of bees assures the pollination of flowering plants. Bee hives additionally produce honey, which is consumed by still other species, such as bears.
-The relationship between the environment and a species is environmental ecology — for example, the consequences of environmental change on bee activity Bees may die out due to environmental changes.
The environment simultaneously affects and is a consequence of this activity and is thus intertwined with the survival of the species.
Disciplines of ecology
Ecology is a broad discipline comprising many sub-disciplines. A
common, broad classification, moving from lowest to highest complexity, where complexity is defined as the number of entities and processes in the system under study, is:
• Ecophysiology examines how the physiological functions of organisms influence the way they interact with the environment, both biotic and abiotic.
• Behavioral ecology examines adaptations of the individual to its environment.
• Population ecology studies the dynamics of populations of a single species.
• Community ecology focuses on the interactions between species within an ecological community.
• Ecosystem, ecology studies the flows of energy and matter through the biotic and abiotic components of ecosystems.
• Systems ecology is an interdisciplinary field focusing on the study, development, and organization of ecological systems from a holistic perspective.
Landscape ecology examines processes and relationship across multipleecosystems or very large geographic areas.
Unit 12 Branches of Ecology. Part 2
1 Introduction
1.1 Read the text title and hypothesize what the text is about. Write down your hypothesis.
1.2 What do you know concerning this issue? List your ideas in the table left column “I know I know that... I have learnt that...
1.3 If you know answers to these questions write them down in the space given after each question. _____________________________________________________________________________
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1.4 Circle in the list the words and expressions you know. Write down their translation in the table and calculate the percentage of your lexical competence.
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Biosphere
For modem ecologists, ecology can be studied at several levels: population level (individuals of the same species in the same or similar environment), biocoenosis level (or community of species), ecosystem level, and biosphere level.
The outer layer of the planet Earth can be divided into several compartments: the hydrosphere (or sphere of water), the lithosphere (or sphere of soils and rocks), and the atmosphere (or sphere of the air). The biosphere (or sphere of life), sometimes described as "the fourth envelope", is all living matter on the planet or that portion of the planet occupied by life. It reaches well into the other three spheres, although there are no permanent inhabitants of the atmosphere. Relative to the volume of the Earth, the biosphere is only the very thin surface layer which extends from 11,000 meters below sea level to 15,000 meters above.
It is thought that life first developed in the hydrosphere, at shallow depths, in the photic zone. (Recently, though, a competing theory has emerged, that life originated around hydrothermal vents in the deeper ocean, i Multicellular organisms then appeared and colonized benthic zones. Photo-synthetic organisms gradually produced the chemically unstable oxygen-rich atmosphere that characterizes our planet. Terrestrial life developed later, after the ozon layer protecting living beings from UV rays formed Diversification of terrestrial species is thought to be increased by the continents drifting apart, or alternately, colliding. Biodiversity is expressed at the ecological level (ecosystem), population level (intraspecific diversity), species level (specific diversity), and genetic level. Recently technology has allowed the discovery of the deep ocean vent communities. This remarkable ecological system is not dependent on sunlight but bacteria, utilizing the chemistry of the hot volcanic vents, are at the base of its food chain.
The biosphere contains great quantities of elements such as carbon, nitrogen hydrogen and oxygen. Other elements, such as phosphorus, calcium, and potassium, are also essential to life, yet are present in smaller amounts. At the ecosystem and biosphere levels, there is a continual recycling of all these
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elements, which alternate between the mineral and organic states.
While there is a slight input of geothermal energy, the bulk of the functioning if the ecosystem is based on the input of solar.energy. Plants and photosynthefic microorganisms convert light into chemical energy by the process off
)hotosynthesis, which creates glucose (a simple sugar) and releases free oxygen, Glucose thus becomes the secondary energy source which drives the ecosystem. Some of this glucose is used directly by other organisms for
energy. Other sugar molecules can be converted to other molecules such as
amino acids. Plants use some of this sugar, concentrated in nectar to entice pollinators to aid them in reproduction.
Cellular respiration is the process by which organisms (like mammals) break the glucose back down into its constituents, water and carbon dioxide, thus regaining he stored energy the sun originally gave to the plants. The proportion of photosynthetic activity of plants and other photosynthesizers to the respiration of other organisms determines the specific composition of the Earth's atmosphere, particularly its oxygen level. Global air currents mix the atmosphere and maintain rearly the same balance of elements in areas of intense biological activity and areas of slight biological activity. Water is also exchanged between the hydrosphere, lithosphere, atmosphere and biosphere in regular cycles. The oceans are large tanks, which store water, ensure thermal and climatic stability, as" well as the transport of chemical elements thanks to large oceanic currents.
The ecosystem concept
The first principle of ecology is that each living organism has an ongoing and continual relationship with every other element that makes up its environment. An ecosystem can be defined as any situation where there is interaction between organisms and their environment.
The ecosystem is composed of two entities, the entirety of life, the biocoenosis, and the medium that life exists in, the biotope. Within the ecosystem, species are connected by food chains or food webs. Energy from the sun, captured by primary producers via photosynthesis, flows upward through the chain to primary consumers (herbivores), and then to secondary and tertiary consumers (carnivores and omnivores), before ultimately being lost to the system as waste heat. In the process, matter is incorporated into living organisms, which return their nutrients to the system via decomposition, forming biogeochemical cycles such as the carbon and nitrogen cycles.
The concept of an ecosystem can apply to units of variable size, such as a pond, a field, or a piece of dead wood. An ecosystem within another ecosystem is called a microecosystem. For example, an ecosystem can be a stone and all the life under it. A meso ecosystem could be a forest, and a macro ecosystem a whole eco region, with its drainage basin.
Unit 13 Energy
1 Introduction
1.1 Read the text title and hypothesize what the text is about. Write down your hypothesis.
1.2 What do you know concerning this issue? List your ideas in the table left column “I know”.
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1.3 If you know answers to these questions write them down in the space given after each question.
How can we define the term “energy”? | |
What are the main energy sources? | |
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What are renewable sources of energy? | |
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What is the difference between renewable and non-renewable sources of energy? | |
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How many types of energy do you know? | |
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Which energy sources do we most commonly use? | |
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What negative consequences does the extraction of fuel produce? | |
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1.4 Circle in the list the words and expressions you know. Write down their translation in the table and calculate the percentage of your lexical competence.
renewable |
| solar power |
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to erect dams |
| consumption |
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deforestation |
| harmful chemicals |
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strip mining |
| drawbacks |
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fuel |
| pollutant |
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replacing soil |
| nuclear power |
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to devastate |
| mine tailings |
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coal |
| exploration |
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Foreign Language University Training
Energy is defined, by Daniel D. Chiras, as «the capacity to do work», and is found in many forms, including heat, light, sound, electricity, coal, oil, and gasoline. Each of these forms of energy provides us with the capacity to light our homes, cook our food, travel by car, train, boat, or plane, to operate factories, and to do a number of other things that we do regularly.
As listed above, energy sources are far and wide. But this is only a cursory list of where energy is found, it is necessary to dig deeper to uncover the true nature of our energy sources. First and foremost, the sun is the ultimate energy source. The heat from the sun gives plants and animals the energy to grow and, in some cases, provides human beings with the energy needed to do some of the things we like to do, such as light our homes or cook our food. The energy from the sun is also partly responsible for the wind on the earth, which we also sometimes use to provide ourselves with power. Solar and wind power are both renewable sources of energy that are currently not widely used. Renewable sources of energy are resources replaced by natural ecological cycles (water, plants, animals) «or natural chemical or physical processes (sunlight, wind)».
Other energy sources that are widely used by human beings include wood, oil, coal, natural gas, the atom (or nuclear power), and moving water, just to name the most commonly used. While it is clear that we benefit by the use of these energy sources everyday by having light in the evening, warm homes, mechanized transport, etc.- we often forget that their extraction and use has severe drawbacks, not to mention the drawbacks of exploration, processing and distribution.
First of all, energy is not just given to us; we have to extract it from the earth. In the case of wood, this means we have to cut down trees to burn to get their energy. To exploit coal and oil, we have to dig or drill. We spend great amounts of time and money to erect dams, altering our rivers and streams to make energy (as well as save water). We have even learned to split the atom to produce energy, which also requires digging into the
earth to retrieve uranium, essential to atomic power production.
All of these extractive activities produce ill effects on the land.
We extract wood from forests for a variety of reasons, one of which is the production of energy. The ill effects of this activity are readily seen on blank hillsides that were once covered with trees. We call this deforestation. But deforestation doesn ’t only produce something unpleasant to see, it also erases animal habitat, alters watersheds, increases erosion into streams and rivers, and depletes the plants and trees that help provide oxygen to the atmosphere.
The extraction of other fuels also produces negative consequences. Coal is generally mined in two ways: strip mining and underground mining (or deep mining). Strip mining causes devastating effects on the land as it involves removing all the earth from atop coal deposits that are close to the earth's surface, extracting the coal, and refilling the scar that is left behind. The practice of strip mining increases erosion destroys wildlife habitat and grazing land, pollutes and depletes water Sources, and creates unsightly views we call eyesores. The roads that must be built into these areas further contribute to erosion, which often fills streams with sediment killing fish and other organisms and reducing the water carrying capacity of the stream, potentially contributing to floods.
Another way of mining coal is underground mining. In underground mining deep tunnels, or mine shafts, are dug into the ground to get to the coal deposits that are being extracted. In this process, underground mines create large amounts of wastes which are brought to the surface and dumped near the entrance of the mine. These wastes, which we call mine tailings, contain heavy metals, acids, and other pollutants, and often find their way into streams and rivers during rain storms.
Oil exploration and extraction from both land and sea can also devastate the environment. On land oil exploration and extraction destroys wildlife habitat through road construction and the clearing of land for drilling equipment. Leaks also heavily affect wildlife, killing animals and the vegetation upon which they depend.
Hydropower is in many ways a very positive energy source. First of all, unlike oil, coal, natural gas, and other fossil fuels, hydropower is renewable like solar and wind power. Also, it creates no air pollution or thermal pollution, and is fairly cheap in comparison to other energy sources. Lastly, hydropower technology is fairly well developed. Hydropower also has its drawbacks though. For one, reservoirs created behind dams fill in with sediments. Most dams have a lifespan of 50-100 years, though some may have a lifespan up to 300 years. Moreover, after reservoirs have filled with sediment they are gone forever. Also, dams may create reservoirs that inundate towns, villages, farm land, and wildlife habitat. So, though hydropower has certain advantages, its disadvantages must also be considered in the use of such an energy source.
In addition to the extraction of energy sources, the consumption of energy sources also has ill environmental effects. Many of the energy sources we most commonly use — coal, oil, natural gas — must be burned to produce energy.
This burning releases harmful chemicals into the air, such as N02, CO, and SO, just to name a few, that pollute the air we and other animals rely on to breathe. Further, nuclear energy does not create air pollution but does create a large amount of radioactive waste which we must find a way of depositing safely, so as not to harm human communities or wildlife.
With all the ill effects of energy exploration, extraction, and consumption it is important to reduce our use of energy, to reduce these effects. But another reason to reduce our use of energy is that most of our energy comes from nonrenewable resources like oil, coal, and natural gas. Nonrenewable resources are resources that are being depleted, or used by humans, faster than the earth can replenish them. So, if we do not reduce our energy consumption, or conserve energy, we may soon run out of nonrenewable energy sources. Also, it is important to remember the first and second laws of thermodynamics, which tell
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a lot about the availability and efficiency of energy. The first law of thermodynamics states that energy is neither created nor destroyed only transformed from one form to another. The second law of thermodynamics I states that when energy is transformed from one form to another, it is degraded: decreasing the amount of useful energy each time it is converted. Last, it is important to use renewable energy sources like wind and solar power whenever possible.
Unit 14
Human-Caused Global Climate Change
1 Introduction
1.1 Read the text title and hypothesize what the text is about. Write down your hypothesis.
1.2 What do you know concerning this issue? List your ideas in the table left column “I know
1.3 If you know answers to these questions write them down in the space given after each question.______________________________________________________________________
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1.4 Circle in the list the words and expressions you know. Write down their translation in the table and calculate the percentage of your lexical competence.
global warming |
| thermal expansion |
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prediction |
| disastrous flood |
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costal area |
| ocean circulation |
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carbon dioxide |
| to raise sea level |
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human activities |
| earth’s rotation |
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to contain |
| to disperse fog |
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torrential rain |
| ice caps |
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monsoon |
| urbanization |
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Are we altering the atmosphere in ways that could lead to disastrous, worldwide climate change? Will increasing concentrations of infrared-absorbing gases released into the atmosphere by human activities trap heat and raise global temperatures? Some climatologists picture a grim future in which summer heat is unbearable, farms are turned to deserts, famines sweep the globe, melting polar ice caps raise sea levels and flood coastal regions, and thousands or even millions of species die that can’t migrate or adapt to sudden climatic charges.
Greenhouse Gases
About half of this predicted warming would be due to carbon dioxide (C02) released by burning fossil fuels, making cement, and
cutting and burning forests. Together, these activities release about 8.5 billion metric tons of C02 annually, causing atmospheric levels to rise about 0.4 percent each year.
Carbon dioxide is not the only gas that could cause climate warming. Methane, chlorofluorocarbons (CFCs), nitrous oxide, and other trace gases also absorb infrared radiation and warm the atmosphere. Although rarer than C02, some of these gases trap heat much more effectively. Methane, for instance, absorbs twenty to thirty times as much—molecule for molecule—as C02, and CFCs absorb approximately 20,000 times as much.
Methane is produced by intestinal bacteria in ruminant animals, anaerobic decomposition in wet-rice paddies, pipeline leaks, decaying wastes in landfills, and releases from coal mining. Atmospheric methane is increasing about 1 percent per year. Chlorofluorocarbons, used as spray propellants, degreasing agents, and refrigerants, have been accumulating at 5 percent each year. The biggest shares of greenhouse gases are produced by the developed countries of the world. Together, the United States, the former Soviet Union, Europe, and Japan are responsible for about two-thirds of all potential global warming!
Effects of Global warming
If greenhouse warming occurs, it probably will not be distributed evenly around the globe. Additional ocean evaporation and cloud cover will likely keep tropical coastal areas about as they are now. The greatest temperature changes are predicted to be at high latitudes and in the middle of continents Siberia and the Canadian arctic might experience increases of 10° to 12° C (18° to 22° F). Chicago might go from an average of fifteen to forty-eight days each year above 32° C (90° F). Dallas may have 162 days per year that hot, rather than 100 as it does now. Calcutta, however, where the temperature is always hot, will not get much hotter.
Rising sea levels are among the most ominous potential results of global warming Some oceanographers calculate that thermal expansion alone could raise the sea level by one meter or more in the next century. An even worse scenario is that polar ice caps might melt. There is enough ice in the Arctic and Antarctica to raise the oceans by 30 meters (90 feet) if it all melted. Most of the world's major cities are on coasts only a few meters above sea level. The homes and businesses of about half the world's population would be threatened if the ice caps melt. A large amount of valuable farmland would also be lost. The U.S. Gulf Coast, for instance, would lose about 5,000 sq km, an area the size of Delaware. A few low- lying countries like the Mal-dive islands in the Indian Ocean might disappear entirely.
Many scientists are convinced that global climate change has already begun. They point to the fact that four of the five warmest years on record were in the late 1980 and early 1990s. When the aerosols released by Mt. Pinatubo are finally washed out of the atmosphere, they predict, high
temperatures will return with a vengeance. Others remain skeptical, arguing that recent high temperatures could be just a random anomaly.
Some studies show increasing temperatures; others show that temperatures are stable or even declining slightly. Current climate models fail to adequately represent effects of water vapor, clouds, air currents, ocean circulation, sulfate aerosols, decreasing solar radiation, biogeochemical ocean processes, or the possible growth stimulation of green plants and ocean plankton by higher C02. If the models assumptions are changed slightly, the predictions change from positive (warming) to negative (cooling) trends.
The atmosphere and living organisms appear to have evolved together so that the present chemical composition of the air is both suitable for and largely the result of biological processes. Compression concentrates most gas molecules in a thin layer (the troposphere) near the earth’s surface. The upper layers of the atmosphere, while too dilute for life, play an important role in protecting the earth’s surface by intercepting dangerous,
mutagenic ultraviolet radiation from the sun. The atmosphere is relatively transparent to visible light that warms the earth’s surface and is captured by photosynthetic organisms and stored as potential energy in organic
chemicals.
Heat is lost from the earth’s surface as infrared radiation, but fortunately for us, carbon dioxide and water vapor that are naturally present in the air capture the radiation and keep the atmosphere warmer than it would otherwise be. When air is warmed by conduction or radiation of heat from the earth’s surface, it expands and rises, creating convection currents. These vertical updrafts carry water vapor aloft and initiate circulation patterns that redistribute energy and water from areas of surplus to areas of deficit. Pressure gradients created by this circulation drive great air masses around the globe and generate winds that determine both immediate weather and long-term climate.
Earth’s rotation causes wind deflection called the Coriolis effect, which makes air masses circulate in spiraling patterns. Strong cyclonic convection currents fueled by temperature and pressure gradients and latent energy in water vapor can create devastating storms. Another source of storms are the seasonal winds, or monsoons, generated by temperature differences between the ocean and a landmass. Monsoons often bring torrential rains and disastrous floods, but they also bring needed moisture to farmlands that feed a majority of the world’s population. When the rains fail, as they do in drought cycles, ecosystem disruption and human suffering can be severe.
Many procedures claiming to control the weather are ineffectual, but some human actions—both deliberate and
inadvertent—may change local weather and long-term climate.
Cloud seeding can induce rain or disperse fog under the right atmospheric conditions. Improving the local situation, however, often makes things worse somewhere else. It is not yet clear what the future of our weather and climate will be. Some scientists warn that the gaseous pollutants we release into the atmosphere may trap radiant energy and cause a global warming trend that could drastically disrupt human activities and natural ecosystems. Understanding and protecting this complex, vital aspect of our world is clearly essential.
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