June 4, 2018
Everyone knows the phrase "water is life". You may use it as a hook for water pollution essay. At present, this problem is the most urgent. Without water, a human cannot live more than three days. But even realizing the importance of the role of water in his life, he still continues to rigidly exploit water objects irrevocably changing their natural regime due to a negative impact of wastes.
The tissues of living organisms consist of 70% water. There is a lot of water on the Earth. But 97% is the salt water of the oceans and seas, and only 3% is fresh water. Three-quarters of this 3% are almost inaccessible to living organisms since this water is "conserved" in glaciers of mountains and polar zones. It is a reserve of fresh water. As for the water available to living organisms, the bulk is in their tissues.
Describe in a water pollution cause and effect essay that before the development of civilization the cycle of water in the biosphere was balanced. The ocean received from rivers as much water as was consumed during its evaporation. If the climate did not change, the rivers would not dry and the level in the lakes would not be lowered.
With the development of civilization, the natural cycle was violated. As a result of irrigation of crops, evaporation from soil increased. The rivers of the southern regions have become shallower. The pollution of the oceans and the appearance of an oil film on their surface have reduced the amount of water evaporated by the ocean. All this worsens the water supply of the biosphere. Droughts become more frequent, and centers of ecological disasters appear.
In addition, fresh water which returns to the ocean and other water bodies from land is often polluted, practically unsuitable for drinking. The relevance of your water pollution research paper should be substantiated by the fact that previously inexhaustible resource becomes exhausted. Today, in many parts of the world, there is not enough water suitable for drinking, industrial production, and irrigation. If you are to give up and buy assignment online, just read this guide and change your mind.
Classification for an essay on pollutions
This is the most common and maleficent type of pollution. It can be organic and inorganic, toxic and non-toxic.
1.1 Toxic organic compounds
Due to the toxicity and resistance, pesticides have become an effective tool for controlling pests and weeds. With their help, a human protects crops and improves yield. At the same time, there are many negative aspects which should be described in a “Pesticide water pollution” essay.
Pesticides cause enormous damage to the environment. Because of their accumulation, natural chains of exchange are disrupted, biological and chemical processes slow down. Due to the lack of natural decomposition, various poisons accumulate in the organisms of animals, plants and reach maximum concentrations. When predatory species of animals eat infected prey, they receive a significant dose of toxic substances which continue to develop in their bodies.
Chemicals, dissolved in rainwater and absorbed by soil particles, fall into the groundwater, and then - in rivers of farmland, where they are accumulated in fish and smaller aquatic organisms. Although some creatures have adapted to these harmful substances, there have been cases of mass death of individual species, probably due to poisoning with agricultural pesticides. For example, insecticides rotenone and DDT, pesticides 2,4-D, etc. caused a severe harm to the ichthyofauna.
Even if the concentration of toxic chemicals is non-lethal, these substances can lead to animal death or other harmful consequences at the next stage of the food chain. It’s worth mentioning in an essay on diseases caused by water pollution that gulls died after eating large amounts of fish containing high concentrations of DDT. Some other fish-eating bird species, including the bald eagle and pelican, were threatened with extinction due to reduced reproduction. Because of the pesticides that got into their bodies, the eggshell became so thin and fragile that the eggs were damaged, and the embryos of the chicks died.
1.2 Toxic Metals
Write in a “Problems of water pollution” essay that lead, mercury, arsenic, cadmium and other toxic metals also can accumulate in the water environment. With a prolonged, gradual increase in the dose, the same damage is caused as when receiving a single large dose.
A high level of mercury is observed in industrial effluents, lakes, and rivers. Passing through the organisms of bacteria, the toxic substances become even more harmful. Getting into the bodies of people and animals, these poisons cause dysfunctions of the nervous system, brain, and even mutational processes.
Today, fish contaminated with methylmercury regularly gets at our dining tables. Even if the fish does not die due to the absorbed substances, it performs an intermediary role. A human can suffer from poisoning. Also, a lethal outcome is possible.
Another poison that accumulates in the water bodies is arsenic. The scientists found it in cleansers, dyes used in the production of toilet paper, napkins.
Lead was found in industrial waters. It is used in the metal industry, in the manufacture of batteries, gasoline, glass, insecticides, and paints. The same applies to cadmium which is used at battery factories.
1.3 Other inorganic pollutants
Inform the readers of a water pollution argumentative essay that, in the intake basins, some metals (such as iron and manganese) are oxidized in a result of chemical or biological (under the influence of bacteria) processes. For example, rust is formed on the surface of iron and its compounds. Soluble forms of these metals exist in different types of sewage. They were found in the waters leaked from mines and dumps of scrap metal, and also from natural bogs.
Salts of these metals, oxidized in water, become less soluble and form solid residues from solutions. Therefore, the water acquires an unnatural, muddy color. For example, the drainage water of iron ore mines and scrap metal dumps is painted in a red or orange-brown color due to the presence of iron oxides (rust).
Such inorganic contaminants as sodium chloride and sulfate, calcium chloride, etc. (i.e. salts formed during the neutralization of acidic or alkaline industrial effluents) cannot be processed biologically or chemically. Stress in an “Effects of water pollution” essay that, although these substances themselves are not transformed, they affect the quality of the water in effluents. In many cases, it is undesirable to use "hard" water with a high salt content, since it forms a sediment on the walls of pipes and boilers.
Such inorganic substances as zinc and copper are absorbed by muddy bottom sediments of watercourses which take wastewater. Then, together with these fine particles, they are transported by the current. In an acidic environment, their toxic effect is stronger than in a neutral or alkaline environment. In the acid wastewaters of coal mines, zinc, copper, and aluminum reach concentrations that are deadly to aquatic organisms. Some pollutants, even if they are not very toxic, are transformed into harmful compounds during interaction (for example, copper in the presence of cadmium).
2. Biological pollution
2.1. Generation of gases
Use the following biological water pollution facts for an essay. Ammonia is the main product of microbiological decomposition of proteins and animal secretions. Ammonia and its gaseous derivative amines are formed both in the presence and in the absence of oxygen dissolved in water. In the first case, ammonia is oxidized by bacteria with the formation of nitrates and nitrites. In the absence of oxygen, ammonia is not oxidized and its content in water remains stable.
With a decrease in the oxygen content, the formed nitrites and nitrates are converted into nitrogen gas. This often occurs when water draining from fertilized fields and already containing nitrates gets into standing ponds, where organic remains also accumulate. In the bottom sediments of such reservoirs, anaerobic bacteria develop in an oxygen-free environment. They use oxygen present in sulfates and form hydrogen sulfide.
When there is not enough available oxygen in the compounds, other forms of anaerobic bacteria develop. They ensure decay of organic substances. Depending on the type of bacteria, carbon dioxide (CO2), hydrogen (H2) and methane (CH4, a combustible gas without color and odor, which is also called a swamp gas) are formed.
It should be mentioned in an essay on water pollution for school students that artificial materials that decompose biologically increase the burden on bacteria, which, in turn, leads to increased consumption of dissolved oxygen. These materials are purposely created in such a way that they can be easily processed by bacteria, i.e. they can decompose. Natural organic substances are usually biodegradable.
In order to endow artificial materials with this property, the chemical composition of many of them (for example, washing and cleaning substances, paper products, etc.) has been changed. The first synthetic detergents were resistant to biodegradation. But when huge masses of soap bubbles began to flow downstream or to accumulate in the municipal sewage treatment plants and disrupt the work of enterprises (because they were saturated with pathogenic microorganisms), this fact attracted public attention.
Manufacturers of detergents solved the problem by making their products biodegradable. But it’s worth noting in an essay on water pollution that such a decision provoked negative consequences, as it led to an increase in the BOD (biochemical oxygen demand) of watercourses that received wastewater, and, consequently, to accelerating the rate of oxygen consumption.
Eutrophication is the process of enriching reservoirs with nutrients (especially nitrogen and phosphorus), mainly of biogenic origin. The water body gradually turns into a swamp filled with silt, decomposing plant remains. As a result, it completely dries. In natural conditions, this process takes tens of thousands of years, due to anthropogenic pollution, it proceeds very quickly. For example, under the influence of human, it ends in just a few decades in small ponds and lakes.
Explain in a water pollution essay for students that eutrophication increases when plant growth in the reservoir is stimulated by nitrogen and phosphorus which are present in the fertilizer-containing drains from agricultural land, in cleansers and detergents, other wastes. The water of the lake that receives these effluents represents a fertile environment. There is a rapid growth of aquatic plants which capture the space in which fish usually live.
Dying off, seaweeds and other plants fall to the bottom and decompose due to the influence of oxygen-consuming aerobic bacteria, which worsens the habitat of fish. The lake is filled with seaweeds and small animals eating them. Blue-green algae (or cyanobacteria) make the water look like pea soup with a bad smell and fishy taste, cover the stones with a mucous film.
3. Physical contamination
3.1 Thermal pollution
It should be emphasized in an “Air and water pollution” essay that the most serious problems of thermal pollution are associated with thermal power plants. Generating electricity with the use of steam is inefficient because in this case, 37-39% of coal energy and 31% of nuclear energy are used. Despite all the shortcomings, thermal power plants continue to exist.
Most of the energy of the fuel, which cannot be turned into electricity, is lost in the form of heat. The simplest way to get rid of this heat is to release it into the atmosphere. But the more economical method is to use water as a cooler because it is able to accumulate a huge amount of heat with a slight increase in own temperature. Later, water gradually releases heat into the air.
The usual way of using water to absorb heat (direct pumping of fresh lake or river water through a cooler and its returning to natural reservoirs without pre-cooling) causes serious environmental problems. A lake with an area of 810 hectares and a depth of about 8.7 m is required for a 1000 MW power plant.
In comparison with the surrounding water, power plants can raise the temperature by 5-15 °C. If the temperature of the water in the reservoir is 16 °C, the temperature of the water used at the station will be from 22 to 28 °C. In the summer, it can reach 30-36 °C.
Stress in a persuasive essay about water pollution that the rise in temperature in reservoirs adversely affects the life of aquatic organisms. During a long evolution, the cold-blooded underwater inhabitants have adapted to a certain temperature range. For each species, there is a temperature optimum which can vary slightly at some stages of the life cycle.
Within certain limits, underwater organisms are able to adapt to life at higher or lower temperatures. Most of them better adapt to life in warmer than in colder water. However, if a new temperature regime is established suddenly by the hot runoff from industrial enterprises, there is not enough time for acclimatization. As a result, living organisms experience a thermal shock and die.
Thermal shock is the ultimate result of thermal contamination. Release of heated drains into the reservoirs may have other, more insidious consequences. One of them is the influence on metabolic processes. According to Van't Hoff's law, the speed of chemical reaction doubles with increasing temperature for every 10 C.
Since the body temperature of cold-blooded organisms is regulated by the temperature of the surrounding environment, a rise in water temperature enhances the metabolism of fish and aquatic invertebrates, which increases their need for oxygen. At the same time, as a result of an increase in the water temperature, the oxygen content in it decreases.
All these changes cause severe physiological stress and even death. In summer, increasing the water temperature by only a few degrees can cause a 100% mortality of fish and invertebrates, especially those that live near the southern boundaries of the temperature interval.
Artificial warming of water can significantly change the behavior of fish (cause untimely spawning, disrupt migration). If the destructive influence of power plants exceeds the ability of species to self-reproduction, the population declines.
The rise in water temperature can disrupt the structure of the plant world of reservoirs. Specific to cold water algae are replaced by more thermophilic species, and finally, at high temperatures, they are completely displaced.
If thermal pollution is aggravated by the entry of organic and mineral substances into the reservoir (fertilizers from fields, manure from farms, domestic sewage), the eutrophication process is observed.
It’s worth writing in a water pollution essay conclusion that the consequences of thermal influence cause huge damage to natural ecosystems and lead to a harmful change in the human environment. Negative impacts can be divided into the following groups:
- economic (losses due to reduced productivity of reservoirs, costs to eliminate the effects of pollution);
- social (aesthetic damage due to landscape degradation);
- ecological (irreversible destruction of unique ecosystems, extinction of species, genetic damage).
3.2 Nuclear pollution
Radioactive isotopes or radionuclides (radioactive forms of chemical elements) accumulate within food chains since they have a stable nature. In the process of radioactive decay, the nuclei of atoms of radioisotopes emit elementary particles and electromagnetic radiation. This process begins simultaneously with the formation of the radioactive chemical element and continues until all its atoms are transformed by the action of radiation into the atoms of other elements.
Each radioisotope is characterized by a certain half-life - the time for which the number of atoms is halved. Since the half-life of many radioactive isotopes is very long (for example, millions of years), their constant radiation can eventually lead to terrible consequences for living organisms inhabiting water bodies into which liquid radioactive waste is dumped.
Nuclear water pollution research paper topics are very relevant due to the fact that radiation destroys tissues of plants and animals, leads to genetic mutations, infertility, and at sufficiently high doses - to death. The mechanism of the effect of radiation on living organisms has not yet been finally clarified, and there are no effective ways to mitigate or prevent negative consequences. But it is known that radiation accumulates, i.e. repeated irradiation with small doses may eventually act in the same way as a single strong irradiation.
Information for a “How to prevent water pollution?” essay
Problem-solving water pollution essay topics are most useful and relevant. The author should not only describe his attitude to the problem but also offer ways to overcome it, justify their effectiveness. Several ideas are described below.
When designing, building, reconstructing, commissioning economic and other facilities, as well as implementing new technological processes, their influence on the state of water bodies and the surrounding environment must be taken into account. It is necessary to provide for the creation of closed systems of technical water supply. Design and construction of straight-through systems of technical water supply, as a rule, are not allowed.
Mention in a research paper on sources of water pollution that the following facilities should not be put into operation:
- economic and other objects, including filtering accumulators, urban and other landfills that are not equipped with devices and treatment facilities that prevent pollution, clogging, depletion of water bodies;
- water intake and waste disposal facilities without fish protection devices, equipment that takes account of the taken and discharged waters;
- livestock farms and other production complexes that do not have treatment facilities and sanitary protection zones;
- irrigation, watering and drainage systems, reservoirs, dams, canals, and other hydraulic structures before measures to prevent harmful effects on water are taken;
- hydraulic structures without fish protection devices, water intake, and other hydraulic structures without established zones of sanitary protection and observation points for control of indicators of the state of water bodies;
- structures and devices for transportation and storage of petroleum, chemical and other products without equipping them with means to prevent contamination of water bodies, control and measuring equipment for detecting the leakage of these products.
It’s also important to write in a “Water pollution solutions” essay that the transition to a system of emission standards takes place now. The ES is determined for each particular source of emissions in such a way that the aggregate emissions from all sources in the region do not exceed the established standard. The use of ES facilitates the planning and control of environmental activities, increases the responsibility of the enterprises for compliance with environmental requirements and eliminates conflict situations.
Out of the total amount of sewage, 69% part is conditionally clean, 18% - contaminated and 13% - normally purified. Strict criteria for dividing industrial wastewater into normatively purified, contaminated and conditionally clean are absent. Contaminated sewage needs to be diluted with clean water multiple times. The enterprises of oil refining, pulp and paper, chemical industries are major pollutants. Normally purified waters also contain contamination, and up to 6-12 m3 of fresh water per 1 m3 should be used for their dilution.
When thinking what should be included in a short research paper about water pollution, do not forget to stress that measures to control the use of water bodies are associated with the improvement of technological processes, in which the discharge of polluted effluents can be partially or completely eliminated. The use of sewage for irrigation in agriculture is a quite perspective method.
There is a need for an increase in the capacity of treatment plants compared to the volume of wastewater that should be cleaned. The performance of water protection programs is affected by the volume of state capital investments allocated for these purposes, the quality of construction and operation of special complexes and the level of the design decision.
Describing the central problem in a water pollution research paper introduction, you may write that today, the contracting organizations of the construction ministries perform the planned tasks not systematically. They do not ensure the timely commissioning of treatment facilities, allow a poor quality of installation works, deviations from projects, violations of construction norms and rules.
An important factor is the improvement of the use of treatment facilities directly at enterprises, which is possible due to the reduction of the time required for the development of new instruments, their more complete use and strict compliance with the purification technology.
The main market method for regulating environmental protection is pollution charges. There are two types of fees: per unit of emissions and for the use of public wastewater treatment plants. In the first case, the payment is determined by the desired quality of the environment. This mechanism automatically ensures the optimal allocation of resources. The payment for the use of treatment facilities includes a basic fee for the discharge of regulatory wastewater, an additional fee for over-standard discharges, water transportation fees and maintenance fees for the services of water inspectorate.
The size of the fee depends on the age of the treatment facilities, the ability of reservoirs to self-purification, the composition of the effluents.
Stress in an essay about water pollution that the fee mechanism is most effective in the conditions of pure competition when each firm seeks to minimize the costs per unit of output. Under the conditions of monopolies, firms may not set such a goal. Therefore, in the monopolized industries, direct administrative regulation has more advantages.
Types of purification to describe in a “Ways to reduce water pollution” essay
Studying water pollution essay resources with relevant information on this topic, you will find out that, although many industrial enterprises try to clean their drains or to make the production cycle closed and the use of pesticides, other toxic substances is prohibited, the construction of additional and more modern treatment facilities is the most radical and quick solution to the problem.
Primary (mechanical) cleaning
Typically, grids or screens that capture floating objects and particles are installed in the sewage stream path. Then, sand and other coarse inorganic particles descend to sand pits with a bottom with an inclination or get into the sieves. Oils and fats are removed from the surface of the water by special devices (oil traps). For some time, the wastewater is transferred to sedimentation tanks to precipitate small particles.
Freely floating particles are precipitated by the addition of chemical coagulants. The obtained sludge, which is 70% organic, is passed through a special ferroconcrete tank, in which it is processed by anaerobic bacteria. As a result, liquid and gaseous methane, carbon dioxide, mineral solid particles are formed. In the absence of ferroconcrete tank, solid waste is buried, dumped into landfills, burned (which leads to air pollution) or dried and used as humus or fertilizer.
Secondary treatment is carried out mainly by biological methods. Since organic substances are not removed at the first stage, aerobic bacteria are used for decomposition of organic matter on the next level. The main task is to bring the effluents into contact with as many bacteria as possible under conditions of good aeration since the bacteria should be able to consume a sufficient amount of dissolved oxygen.
Sewage is passed through various filters: sand, gravel, expanded clay or synthetic polymers. The same effect is achieved in the process of natural cleaning in the channel flow which has overcome the distance of several kilometers.
On the surface of the filter material, the bacteria form a film and decompose the organics of the wastewater. They pass through the filter thereby reducing the BOD by more than 90%. These are so-called bacterial filters. BOD reduction by 98% is achieved in aerated ponds, where due to forced aeration of sewage and mixing it with activated sludge, natural oxidation processes are accelerated. Active sludge is formed in sedimentation tanks from particles suspended in the waste fluid, which are not influenced during preliminary purification and adsorbed by colloid substances with microorganisms breeding in them.
Another method of secondary purification which may be included in a water pollution essay outline is the prolonged formation of sludge in special ponds or lagoons (irrigation fields), where algae consume carbon dioxide and produce oxygen necessary for the decomposition of organic matter. In this case, the BOD decreases by 40-70%, but certain temperature conditions and solar illumination are required.
After passing primary and secondary purification, sewage still contains dissolved substances which make the water practically unsuitable for any needs other than irrigation. Therefore, more advanced purification methods aimed to remove the remaining contaminants have been developed and tested. Some of these methods are used at facilities that purify drinking water.
Such slow-decomposing organic compounds as pesticides and phosphates are removed by filtering the secondary drainage through activated (powder) charcoal, by adding coagulants that promote agglomeration of fine particles and their precipitation, by treatment with such reagents that provide oxidation.
Dissolved inorganic substances are removed by ion exchange (dissolved ions of salts and metals); chemical precipitation softening the water (calcium and magnesium salts which form a deposit on the internal walls of boilers, cisterns, and pipes); change in osmotic pressure for enhanced filtration of water through the membrane, which detains concentrated solutions of nutrients - nitrates, phosphates, etc.; excretion of nitrogen by the flow of air as the effluents pass through the ammonia-desorption column; other methods. In the world, there are only a few companies that can carry out a full wastewater treatment.
Useful tips for writing of a water pollution essay
If you are going to write an essay or a paragraph on water pollution, it will not be enough just to list the well-known facts. You need to offer an original idea or describe your vision of the problem. This genre assumes complete concentration on the author's worldview. Even if some of your statements diverge from theories of scientists, they deserve to be considered. Nevertheless, do not abuse unfounded assertions. Each thesis must be supported by arguments. Otherwise, the academic paper will turn into demagogy.
As for the structure, adhere to the following outline for water pollution research paper:
- In the introduction, the main idea of the work is presented. Also, you can ask a question and provide a detailed answer later. This method forces readers to reflect, provokes interest.
- Structure of the main part: theses - arguments. You can use an arbitrary number of such pairs (at least 3 to make the paper convincing). At the same time, experts do not recommend overloading work with excessive facts. The reader can simply get confused and forget what kind of idea you put forward at the beginning. Choose only the most important theses and provide reliable arguments.
- In the conclusion, you must return to the statement made in the water pollution essay introduction and emphasize that your arguments confirm the central idea. Do not add new theses and write briefly. 3-4 sentences will be enough.
This is the standard plan which is used regardless of the size of the paper. However, the algorithm for writing an essay differs somewhat from its structure. Experienced authors begin with the main part (formulate the theses and arguments), proceed to conclusions and write the introduction. This is due to the fact that the first sentences are traditionally considered the most important. It depends on them whether the text can cause the reader's interest. Therefore, this detail must be worked out when the author has a clear idea of the essence of his work.
The same applies to the water pollution essay title. A common mistake: students choose a header and write the text. Reaching the conclusion, they notice that the research has nothing to do with the stated topic.
Do not forget to carefully check the paper for punctuation, lexical, stylistic and other errors. Reread the text several times. If you find a lot of mistakes, rewrite the work for a clean copy. Do not be upset if you failed to achieve the ideal on the first try. Even professionals use drafts.
As you can see, the rules for argumentative essay writing are quite simple. It is a free genre prescribing a minimum of formal requirements. So enjoy the creativity and express your thoughts. Still do not know how to start? In order to better comprehend the features of such works, read the water pollution essay examples written by other authors.
We wish you a powerful wave of inspiration and hope that your paper will be highly assessed by teachers. Good luck!