Pollution is a set of adverse effects that have an impact on the biosphere and man, officials from the alteration of factors of existing balances, mostly released as byproducts of human activity in the air, water and soil. There are various types of pollution, but we can say that the most important are the 'pollution of the sea (which we have already said), the' industrial pollution of 'water, or water pollution, pollution from industrial, agricultural and urban areas, the' bacterial contamination el 'pollution of the soil to the accumulation of solid and liquid wastes from industrial and domestic products and by' often use incorrect, agriculture, fertilizers, pesticides etc.. One of the less obvious pollution but is even more difficult to curb the 'thermal pollution, which can produce effects of high magnitude (in the case of a power plant cooling water through a river, for example., One can determine significant changes in 'river habitat and in the composition of fish).
All substances that alter the original composition of the water causing pollution. Some substances derived from soil erosion, or the 'atmosphere, through precipitation, and are quite natural, while real pollution is often caused by human activities and a wrong way to exploit the land. The main polluters of the 'water are the urban, industrial and agricultural use and forestry.
Most of the pollutants are discharged directly into water, the remainder ccircola in 'atmosphere before falling to the ground through precipitation.
The careless use of chemical fertilizers, containing nitrogen, phosphorus and potassium, is one of the major causes of pollution, which must be added to insecticides and herbicides. All that the soil can not absorb the water circulates.
toxic substances discharged from industry and pesticides used in agriculture contaminate the groundwater. When the water contains an excessive residue of fertilizers (nitrogen, phosphorus, potassium), there is a proliferation of algae and aquatic vegetation resulting in deprivation of oxygen.
This causes the rapid growth of anaerobic bacteria, which do not require oxygen. They lay the organic matter by releasing toxic substances. This process, called eutrophication, is observed in rivers, ponds, lakes and even in the sea, which are covered on the surface of a dense layer of algae, while in depth all life disappears.
Some toxic chemicals discharged into the water attach themselves easily focus in animal tissues.
To prevent pollution of water is necessary: \u200b\u200b1) limit, even in the gardens, the use of fertilizers, pesticides and insecticides, and 2) whether all industries purify waste water, and 3) require the city to deal with waste water before placing them in rivers, 4) avoid using products containing phosphates, soaps made from vegetable fats are much less polluting, 5) regularly check the quality of tap water.
Bacterial pollution
life of living organisms is constantly threatened by higher bacteria, lower organisms that attack them with different virulence and danger. Bacteria are widely used in 'environment, so even in water. Water is considered polluted in terms of bacteriological when microorganisms are present in it in such quantities as to pose a health risk.
bacterial pollution, together with that of the soil, which may be associated, has important health consequences of 'man.
The bacterial pollution of 'water is predominantly due to sewage sludge or sewage, in which organic matter There are numerous micro-organisms and, in particular, those which are part of the intestinal flora (coliforms, enterococci, anaerobes, etc...) Among the factors
bacteria and chemical pollution, there are some fundamental differences. While the chemicals are present in solution, the bacteria are physically attached to solid objects, so that their average concentration in water is not representative of the probability of contracting the 'infection. Unlike chemical agent, the bacteria settling in 'body will be multiplied, and some bacteria also proliferate in foods and beverages, thus extending and increasing the risk of infection.
integrity and orderly maintenance of the sewerage system are by far the main tool to effectively prevent infections related to 'bacterial pollution of the waters.
Reflections of water pollution on human health are largely represented by a series of infectious diseases, among them we should remember first of all viral hepatitis, second infections paratyphoid, cholera, finally, also very rare in Western countries. The presence of these diseases resulting from pollution of groundwater intended for drinking.
The resistance of bacteria in the water depends on several factors, among them, temperature is the most decisive: the bacterium fell more rapidly with increasing temperature and ultraviolet rays.
The purification of the water that is ingested and is used in every household is a major condition for the good health of humans and animals, but to control the pollution of water are also needed good drainage in the areas occupied by landfills, the elimination of open sewers and an efficient sewerage system.
ALGAE
algae that you talked so much about appeared in the remote past and were more primitive, along with bacteria, among the first living things that inhabit our planet, and later developed with exuberant vitality, giving rise to many different types.
immersed in water, which is the living environment for the vast majority of species, algae derive their livelihood from it. All, with few exceptions, are equipped with chlorophyll, such as higher plants and can eat at the expense of minerals dissolved in water, using sunlight as an energy source. They have distributed all the chlorophyll in their outer cells exposed to light and take carbon dioxide out of the water, where it is dissolved.
The main limitation to the spread of drift algae, however, its function from chlorophyll, which is absolutely necessary for the light. Since live in water, which absorbs light radiation, the algae spread only within a certain range of depths in the seas and large lakes, ie up to where there's light radiation; deeper than their life is impossible.
Their distribution depends on the 'adaptation of the algae themselves to different environmental conditions, at various depths, and especially the change of light, water temperature and its salinity. In Rio
Pramaera the highest concentration of algae is called 'micro-plankton'.
In the highest part of the sea-coast, and during low tides is partially open, dominated by "green algae", called "Cloroficee" (from the greek = chlorosis and fucose = green algae). It 's the most intensely illuminated zone. They are in the nature of their function in the mechanism of chlorophyll and chlorophyll, close similarities with terrestrial plants, they vegetate in great numbers in fresh water, forming floating masses on the ponds. More than 90% of their species (6500 in total) live in lakes, in pools, streams. Many have adapted to live outside 'water in very special conditions. If
in most cases, the algae are part of the essential food chain of many species of fish, if they too can obstruct the passage of light in different stretches of 'water and eat well all the oxygen.
The proliferation of algae-induced crop water eutrophication (extraordinary enrichment in nutrients) caused by human negligence is now a among the most worrisome environmental emergencies. It determines the lowering of the rate of O2 in the water, making it inhospitable for many species (of fish die-offs).
Implications for the malfunctioning of the sewage treatment
One consequence of malfunctioning of the sewage treatment plant in the country (which we have mentioned several times) it can be noted even overlooking the river ....
An expanse of algae, fed by substances from the water purifier through an open channel, covering a large part of the river with some positive consequences.
Algae absorb the oxygen present in water or deprive the fish with inevitable asphyxiation. Later, when the algae no longer going to live on the surface are dragged by the currents towards the mouth, and then drops into the sea with the inevitable disappointment of the many swimmers who occupy the beach.
And this is one of many reasons why it is essential to the opening "day" of the mouth.
Another consequence can be seen on the river bank, that if a time we could notice us alive and vibrant Tremolina (important food for fish that live there), with poorly functioning sewage treatment plant there are often high mortalities.
Many wetlands are threatened by drainage and reduced water inflows, and this because of dams, artificial embankments, funnels or other human interference and a few rivers are free from pollution (fertilizers and sewage encourage the abnormal growth algae, which consume all the dissolved oxygen and kill all forms of aquatic life).
The rivers draining the land collecting excess rainwater and thereby shape the natural landscape. Initially, the rivers are fast torrents that erode the mountains and hills to the sea carrying mud, minerals and key chemical elements. Downstream slow down their progress, in plain placid flow around bends and meanders, creating lakes and swamps, and when flowing into the sea often branch to form a fertile delta.
Thanks to this continuous cycle of erosion and deposition of debris, the rivers have shaped the landscape over millions of years. Most of the rivers form a large river system with hundreds of small streams online.
flaps nature: Even isolated fragments of a swamp or a bog can accommodate a number of unexpected animals and plants almost disappeared elsewhere. The reed beds are one of the most typical habitat of wetlands. In the midst of them find shelter and numerous species of nesting birds like the bittern, which features a camouflage color pattern is one of the wetland birds more difficult to observe.
deliberate destruction: vital to many life forms, wetlands are often replaced by fields.
When a water plant dies the moist environment prevents the complete decomposition and its remnants are transformed into peat. Over the years the peat accumulates, forming layers of nutrient compounds that turn into a very fertile ground, sought by farmers. In reality, wetlands are valuable. The their waters, inhabited by organisms that act as biological filters, turning organic waste into fertilizer, while aquatic plants can filter out large quantities of lead, cadmium, nickel and zinc.
The future of these areas is linked to the recognition of their function as refuges for wildlife.
harmful imbalance: The rapid growth of the human population has led to an increasing exploitation of rivers. The bacteria found in rivers are able to purify water, but the excessive increase in the rate of pollution caused by industry, agriculture and discharges citizens has blocked this natural process. Rivers reduces the amount oxygen and suffocate fish and other animals, or are poisoned, while the human communities that draw drinking water from the bottom of a river may lead to serious diseases. It follows that the pollution of rivers, seas and lakes.
waters that normally would be contained in the wetlands quickly end up in rivers, causing sudden and destructive floods.
Today we make great efforts to repair the damage committed over many decades and make the rivers a source of life for the flora, fauna and man himself. In many industrialized countries, advances in technology applied in the treatment of waste water companies have reduced the rate of pollution Rivers: today the fish back into water courses that had abandoned.
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