Environmental effects of pollution of the hydrosphere

Hydrosphere — the most important element of the biosphere, unites all the waters of the globe, including oceans, seas and surface water from land. By the hydrosphere was treated the same underground water, ice and snow in the Arctic and Antarctica, atmospheric water and water contained in living organisms. Water masses in the earth’s surface form a thin shell, which occupies most of the planet’s surface and forms the world’s oceans. Water surface of the planet is 71%, and in view of glaciers and snow cover — 86% of its total surface. According to current estimates, the volume of water on the planet is approximately 1.39 billion cubic meters. But 96,4% of the hydrosphere, the water falls on mineralized waters of the seas and oceans, fresh water makes up only 2.65% — although this figure does not reflect the actual amount available for consumption of fresh water. If we take all the fresh water for 100%, it becomes evident that a large part of it — 70.2% «locked» in the form of ice and permanent snow cover, mainly in the ice sheets of Antarctica and Greenland. Another sizable portion — 28.7% are in the lithosphere. Only 0,27% of the total fresh water readily available for use, flows through the planet’s surface in the form of rivers, accumulates in lakes and reservoirs. But these small percent of fresh water would be enough if it was evenly distributed across the planet and its anticipated expenditure solely for domestic purposes. Unlike mineral resources, water is a renewable natural resource. Being in a natural cycle, the water falls to earth as rain, solid precipitation, with river flows back into the sea, then from the surface of smooth sea surface evaporates into the atmosphere and re-transformed into the clouds, only to again fall to the ground of life-giving moisture.

Water ensures the existence of living organisms on Earth, and the course of their life processes. It is part of the cells and tissues of any animal and plants. On average, water is about 90% of the mass of all plants and 75% of the mass of animals. Climate and weather on Earth is largely dependent on and determined by the presence of water spaces and water vapor content in the atmosphere.

In human water are widely used. Water is used in industry, serves as coolants used in the construction and. Agricultural activities associated with the consumption of vast quantities of water. Rivers, canals, lakes — important means of communication.

Historically, people have always settled near water sources. They provided them with fresh water, were given water for irrigation and production development. In the middle of XX century, mankind has created new opportunities in the sustainable provision of water resources: they built reservoirs and canals, artesian wells were drilled. Along with increases in capacity and the emergence of an increasing need for fresh water — has grown, and the ability to waste water, waste, without looking back. In terms of everyone on the planet quantity intake increased from 140 to 780 liters per day. And in all the calculations of water consumption, taking into account agriculture, industry and domestic needs, never taken into account other important consumer of water — environment.

As a result of irrational consumption expenditure of the water began to exceed the rate of recurrence. Rivers no longer reach the sea, drying lakes, depleting aquifers, degraded ecosystems — all due to overruns in the water and the underestimation of the value of this resource in ill-considered policy of consumption.

This is the century, as water consumption is growing faster than the population of the planet. Over the past 100 years its population has increased by 4 times, but water consumption increased by 7 times. The highest consumption of fresh water is manifested in the regions of irrigated agriculture, as well as in urban agglomerations and industrial centers.

Now in the world for agricultural, industrial and domestic water consumed more than 4 thousand cubic kilometers per year, representing about 4,5% of fresh water, concentrated in lakes, reservoirs and rivers. One day is spent around 10 billion tons of water, which is comparable with the annual production of all kinds of minerals.

The highest amount of fresh water consumption occurs in Asia (60% of global consumption), which are the main irrigated area of the planet, about 15% — in North America, at around 13% — in Europe, the remaining 12% is divided about equally between South America and Africa.

And, despite the proportion of water used in industry and for municipal needs, the lion’s share of water consumption at the beginning of XX century, and now goes to agriculture in developing countries, accounting for 80% of total water consumption.

Major water loss from small farmers in developing countries using outdated methods of irrigation. Many studies in the field of plant breeding is now focused on developing new drought-resistant crops and the development of drip irrigation system, saving up to 70% of fresh water.

As a result of irrigation have crises of entire river systems, characterized by excessive water consumption and reduced drain, which primarily include the Colorado River, the Ganges, Indus, Jordan, Nile, Tigris, Euphrates, and others. Evolving situation is aggravated by pollution of surface waters and the active development of groundwater.

Excessive use of water leads to a sharp decrease in groundwater levels. Thus, farmers Yemen, living near the river Sana, in recent years have been forced to deepen their wells, an average of 50 meters, and the number of extractable water are reduced by two thirds. In some areas of India, water tables are falling by more than 1 meter per year, causing a crisis for agricultural production.

But the most striking example of an environmental disaster resulting from ill-conceived irrigation — the Aral Sea. As a result, water from the Syr Darya and Amu Darya were obtained by record crops of cotton, but almost lost forever sea with a unique biodiversity. Undertaken in recent years of the suspended catastrophe, but the old shape of the sea and a combination of flora and fauna will not be able to achieve.

For flood protection and water conservation in the dry season has long been constructing dams and reservoirs. In the world today there are at least 30,000 reservoirs with a total area of more than 500 million cubic meters, for example, that surpasses the area of the Black Sea. Reservoirs are primarily designed to equalize the flow, as well as for hydropower and irrigation. However, regulation of river flow has negative consequences for ecosystems: reduced water exchange, and transit in the nature of the type of cycling is becoming more closed.

In addition to reducing runoff of rivers in the operation of water and coastal ecosystems is effective construction of hydraulic structures. So, now, only 21 of the 177 largest rivers of the world have free access to the sea, and most of them are blocked by dams, water intake systems. And if in the middle of XX century, large dams were about 5000, but now their number had increased to 45,000. Accordingly, all kinds of organisms that live in these rivers, live under the regime, significantly different from usual habitat. According to WWF, from 10,000 varieties of freshwater species, about 20% have either become extinct or are on the verge of extinction.

Obviously, in terms of population growth and increasing demands for food, urbanization and industrial growth, competition for water in coming decades will increase. The UN estimates that drinking water supplies in the world each year is declining, but in the world’s oceans get millions of tons of oil and waste. Drinking unsafe water — the cause of almost 10% of all diseases in the world and 6% of all deaths. The main victims are children: Children up to 14 years, this is the reason 22% of all zabolevaniy. 15

According to the International Committee on Climate Change, in the near future climatic contrasts will increase: change in rainfall patterns will lead to an increase in droughts in some parts of the world and flooding in others. This will further aggravate the supply of fresh water in areas of the desert climate, characterized by low rainfall and lowering of groundwater. According to forecasts, by 2015 in countries with chronic water shortages will house more than half the world’s population, and by 2025, 2 / 3 of mankind will already have its drawback. Lack of fresh water, in turn, could trigger a shortage of food resources. These difficulties are compounded by the fact that currently not there are no influential international organization or international law that would regulate the distribution of water.

And some Gulf countries, faced with acute shortage of fresh water, have already begun to desalination of sea water. In recent years, seriously discussed projects on transportation of Antarctic icebergs. But many believe that the main problem is not so much a shortage of fresh water, as wasteful in its use. Many Western countries have already developed a range of water saving technologies.

Anthropogenic influence on climate is manifested in pollution and depletion of water. The natural self-purification capacity has its limits. For the first time the problem of river pollution occurred during the industrial revolution, together with urban growth and the rise of the machine and factory production. Industrial and domestic waste water flowed into ponds, and then untreated, contaminated water flows into the aqueduct, causing outbreaks of infectious diseases.

The main sources of pollution of surface water are: discharges into watercourses untreated sewage, pesticides, erosion, mineral and organic fertilizers; gas emissions, oil spills and oil products.

It took 200 years, during which increased the number of earthlings, there is intensification of agriculture, develop industry, growing cities. As more of these components of the pollution and the number of species grew exponentially, resulting in natural water sources to the disappointing performance of contamination. Many of the river «absorb» waste, was similar to the lifeless waste ditch, which flows no longer water, but the «chemical cocktail».

15 of the magazine «Ecology and Life» № 9 of 2008, page 19

Water pollution has covered not only the land but also the world’s oceans. Ocean pollution accumulates all the air and river flows, as a final point of discharge. Under the influence of eddies undercurrents all plastic rubbish thrown away by people in the ocean, going in one place. This scrap-heap starts at about 500 miles off the coast of California, stretches across the northern part of the Pacific past Hawaii and reaches almost to Japan. 100 million tons of floating debris occupy the area, twice the continental USA. Oceanology, followers of this phenomenon that rubbish tip moves across the planet. When it approaches land, the bank gets a huge amount of plastic. Even 50 years ago, debris falling into the ocean, was subjected to decay, but the modern plastics are so durable, that is stored in seawater desyatiletiyami.16 As the degree of pollution increases the risk not only reduce the diversity of living organisms in natural waters — a critical pollution can lead to what caught fish to eat will soon be unsafe.

By the early twentieth century, more than 40% of the oceans affected by human activity and only 4% are not exposed to the destructive effects, while maintaining the natural ecosystem intact. Together, a number of leading research centers in the U.S. recently prepared the first in the history of science Atlas of the Oceans, which reflected the impact of human activities on the 17 characteristics. According to the data reflected in the Atlas, the greatest damage has been done in such areas as the North Atlantic, western Pacific Ocean, Bering Sea, East China, the Caribbean, Red Sea, the Mediterranean and South China Sea and the Persian Gulf, many violations of ecosystems are considered irreversible . The best position are the Arctic Ocean and other oceans of water, washing Antarktidu. 17

Among the industrial waste water and the most intensive sectors of the economy «lead» the big consumers of water, which include energy, ferrous and nonferrous metallurgy, machine building, chemical, petrochemical, wood-chemical, petrochemical industry, as well as housing and agriculture. This drain pipe is often very difficult to detect because they are immersed in water and are usually outside the Pale of settlement. Industrial waste water depending on the specific industries include petroleum products, synthetic surface active substances (surfactants), phenols, fluorides, heavy metals and so on.

Gazodymovye releases fall into water from precipitation and in the process of mechanical settling. They contain both coarse contaminants, which include ash, soot, dust and gases, primarily sulfur dioxide and nitrous oxide, which, when combined with water forms sulfuric and nitric acid.

Chemical fertilizers and pesticides have appeared as a contaminant along with the «green revolution». Only 30-50% of fertilizers and insecticides, introduced to the fields to increase yields and ridding crops of pests, plant uptake, and the remainder accumulates in the soil and, together with the melt and rain water is carried into the reservoirs. In areas where water is weakly running and well heated, add nitrogen and phosphorus in the aquatic environment is the ideal «fertilizing» for algae and cyanobacteria. It starts with their rapid reproduction, and therefore — «bloom» and the turbidity of water. Accordingly, the depth of penetration of sunlight decreases, which leads to the death of benthic plants. Lack of oxygen then leads to massive fish kills. This process is called «eutrophication».

It is oil and petroleum products moved into first place among the pollutants of oceans and seas. The main causes of pollution by these substances of the seas and oceans are sinking and oil discharges to wells located in the high seas. We know that one ton of oil, spreading over the surface of the ocean, occupies 12 square kilometers. Every year in the ocean, according to various estimates, gets about 10 million tons of oil. Oil, creating a film on the surface of water, prevents gas exchange, including the absorption of water of oxygen. Lack of aeration and oxygen deficiency leads to the death of many aquatic organisms.

In aquatic ecosystems, also reflected the impact of acid precipitation. Most strongly manifested in this inland seas, such as the Baltic Sea. Development of nuclear energy led to the spread of radionuclides originating from nuclear power plants and waste ships with nuclear engines.

Thus, slowly, step by step, the world is squandering one of the important natural resources, increasing the ecological debt, which will inherit the future generations.

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