(1) Color change. Natural water is colorless and transparent. Water pollution can make the water color changes,
thus affecting the senses. Such as printing and dyeing wastewater pollution tends to make the water color red, oil refinery wastewater pollution can make the water color black and brown,
and so on, the water color change, not only affect the senses, destroy the landscape, and sometimes very difficult to deal with.
(2) turbidity changes. The water body contains sediment, organic matter and inorganic substances suspended and colloidal substances,
Turbidity phenomenon, so as to reduce the transparency of the water, which affects the sensory and even affect the life of aquatic organisms.
(3) foam. Many pollutants discharged into the water will produce foam, such as detergent. Floating on the surface of the water
foam, not only affects the perception, but also in its pores inhabited by bacteria, resulting in domestic water pollution.
(4) odor. Water odor is a common pollution phenomenon. Water body odor is mostly organic matter in
Smack gas state corruption odor, is a comprehensive malodor, there is a clear gutter smell. The harm of malodor is to make people hold their breath,
nausea, aquatic products can not eat, the water body to lose the function of tourism and so on.
2, what is organic pollution of water bodies?
Mainly refers to the pollution caused by municipal sewage, food industry and paper industry and other emissions containing a large number of organic wastewater
. These pollutants in the water for biological oxidation and decomposition process, need to consume a lot of dissolved oxygen,
Once the oxygen supply in the water body is insufficient, it will make the oxidation stop, causing the anaerobic fermentation of organic matter, emitting
foul smells, polluting the environment, poisonous aquatic organisms.
3, what is inorganic pollution of water?
The acid, alkali and inorganic salts on the water pollution, first of all, the water PH value changes, destroying its
natural buffer, inhibit the growth of microorganisms, impede the self-purification effect of the water body. At the same time, it will also increase the water inorganic
salts and water hardness, to the industrial and domestic water to bring adverse effects.
4, what is the water body of toxic substances pollution?
All kinds of toxic substances into the water body, in high concentrations, will kill the water organisms; in low concentrations,
can be enriched in the organisms, and through the food chain level by level concentration, and finally affect the human body.
5, what is the eutrophication of water pollution?
Wastewater containing plant nutrients into the water body will cause eutrophication of the water body, so that algae bloom,
and a large number of consumption of dissolved oxygen in the water, which leads to asphyxiation and death of fish and other.
6. What is oil pollution in water bodies?
Coastal and estuarine oil development, tanker transportation, discharge of waste water from the oil refining industry, etc., and when the oil in the
water surface to form an oil film, affecting the oxygen into the water body, causing harm to organisms. In addition, oil pollution also destroys sea
beach rest areas, scenic landscapes and the survival of birds.
7, what is thermal pollution of water bodies?
Cooling water from thermal power plants and other sources is a major source of thermal pollution. This wastewater is discharged directly into natural water bodies, which can
causes the water temperature to rise, resulting in a reduction of dissolved oxygen in the water, but also makes the water toxicity of certain toxins rise. Elevated water temperatures
have the greatest impact on fish, which can cause population changes and mortality.
8, what is the pathogenic microbial contamination of water?
Living sewage, hospital sewage and sewage from slaughtering and meat processing contain various types of viruses, bacteria, parasites
Pathogenic microorganisms such as worms, which flow into the water body can spread various diseases.
9, cyanide pollution and its harm?
In electroplating and other industries can produce a large number of wastewater containing cyanide, cyanide can be through the respiratory tract, esophagus and skin
skin immersion and cause poisoning. In mild cases, there are symptoms of mucous membrane irritation, numbness of the lips and tongue, asthma, nausea, vomiting, palpitations.
Serious cases, respiratory irregularity, consciousness gradually coma, incontinence, can quickly occur respiratory impairment and death.
Cyanide poisoning may also occur after the cure of neurological sequelae, water cyanide concentration exceeds 0.03 mg/
liter, fish poisoning.
10, chromium pollution mode and its harm is what?
Chromium has a wide range of industrial uses, mainly in metal processing, electroplating, tanning industries, which emit waste
water and exhaust gases that are major sources of pollution in the environment.
Chromium is one of the trace elements necessary for the human body, but excessive chromium is harmful to human health; hexavalent chromium is
more toxic, more absorbed by the human body, carcinogenic, and can be accumulated in the body. Excessive (more than 10ppm)
Trivalent chromium and hexavalent chromium are lethal to aquatic organisms.
11. What is the pollution of detergents and their hazards?
The active ingredients of synthetic detergents are surfactants and purifying agents, in addition, there are a variety of auxiliary
assisting ingredients such as bleach. Surfactants can be categorized into cationic, anionic and
nonionic according to their molecular configuration and type of groups. The latter two are used in large numbers in industry and life.
Wastewater containing synthetic detergents are mainly washing Qi production wastewater, industrial detergent cleaning water, laundry
factory drainage and catering and domestic sewage. Discharged into the water body, the consumption of dissolved oxygen, and aquatic organisms have a slight
toxicity, can cause fish deformity, which contains phosphate solvents will cause eutrophication of water bodies.
12, organochlorine pesticide pollution and its harm?
Organochlorine pesticides are basically divided into two categories of compounds based on cyclopentadiene as raw materials. Chlorobenzene
structure is more stable, biological body enzymes are difficult to degrade, so the accumulation of organochlorine pesticide molecules in animals and plants
disappear slowly. Because of this characteristic, it is through biological enrichment and the role of the food chain, residual pesticides in the environment
will be further agro-collected and diffused. Organochlorine pesticides that enter the body through the food chain can accumulate in tissues such as the liver, kidney and heart
, especially because of the large fat solubility of these pesticides, so the positive factors in the body fat storage
more prominent. Accumulated pesticide residues can also be excreted through breast milk or transferred to tissues such as eggs and eggs, affecting offspring.
China began banning the use of DDT and hexachloroethylene on crops such as sparse vegetables, tea and tobacco in the 1960s.
13, what is biochemical oxygen demand (BOD)?
Biochemical oxygen demand (BOD) is the amount of organic matter contained in the water by microbial biochemical degradation of the amount of
oxygen consumed. It is a measurement based on microbiological principles. All factors affecting microbial degradation,
such as temperature and time, will influence the BOD measurement. The final BOD is the amount of oxygen required for the biochemical degradation of all organic matter
to a simple end product. Generally 20°C and 5 days of incubation are used as standards. Expressed in terms of
BOD, the unit of measurement of BOD is usually in mg/l or ppm.
14, what is chemical oxygen demand (COD)?
Chemical Oxygen Demand (COD), is in certain conditions, with a certain strong oxidant treatment of water samples consumed
the amount of oxidant, expressed in milligrams of oxygen/liter, which is indicative of the body of water is polluted by reducing substances of the main indicators
Significantly, the reducing substances, including a variety of organic substances, nitrites, ferrous salts and sulfide, etc., but the water samples are polluted by organic
Something is extremely common. >Substance pollution is extremely common, so the chemical oxygen demand can be one of the indicators of the relative content of organic matter. Chemical oxygen demand
Oxygen determination, according to the different oxidizing agents used, divided into potassium permanganate and potassium dichromate method. Potassium permanganate
four method is easy to operate, the time required is short, to a certain extent, can be described by the status of organic pollution of the water body,
often used for less polluted water samples, potassium dichromate method of organic oxidation is more complete, applicable to a variety of
water samples.
15. What is the greenhouse effect and its impact on global climate change?
The temperature and climate of the earth's surface is determined by solar radiation, the earth's energy absorbed from the sun must be balanced with the radiant energy released from the earth
and the atmosphere, the earth's temperature can be stabilized within a certain range. To
maintain this balance, a portion of the Earth's outgoing energy is absorbed by radiative atmospheric gases (i.e., greenhouse gases)
and re-reflected back to the Earth, thereby reducing the net emission of energy into outer space, which is known as the greenhouse effect. The main greenhouse gases in the natural world are carbon dioxide, water vapor, methane, nitrous oxide, and ozone. Human activities
On the one hand, a large amount of carbon dioxide emissions, especially since the industrial revolution, the use of fossil fuels continue to increase dramatically
On the other hand, a large number of destruction of forests, grasslands, so that the Earth is losing carbon dioxide storage
preparation reservoirs, the concentration of greenhouse gases in the atmosphere in the rapid increase in the planet with the slowing down of the release of energy outward, resulting in a
Not the same.
Abnormal greenhouse effect. The immediate danger of the abnormal greenhouse effect is that it raises global temperatures. According to
Scientists calculate that doubling the concentration of carbon dioxide will increase the global average temperature by 1.5 to 7 ℃, the high
latitude regions increased by 4 to 10 ℃, such a rapid rise in temperature will cause the Earth's glaciers melt, leading
to the rise in ocean level, so that many coastal cities suffered a catastrophe.
Scientists after a large number of observations, the abnormal greenhouse effect is caused by global climate change is an important original
cause, and the most important lies in the Earth's excessive carbon dioxide, the past one hundred years, the Earth's surface temperature has risen
0.3 to 0.6, of course, there are still differences in the academic community on this, but the majority of people believe that global warming will give mankind caused
The global warming will cause very serious social and regular problems for human beings, so it is necessary to take early and practical preventive and control measures.
16. What is the destruction of the ozone layer and what are its dangers?
The ozone layer refers to the atmosphere 10 to 50 kilometers from the Earth's surface by the ozone layer. Ozone is
a gas whose molecular structure is three oxygen atoms, O3. The main function of the ozone layer is to absorb ultraviolet rays from the
Zeus, so that everything on the Earth is free from the harmful effects of ultraviolet radiation, so the ozone layer is known as the earth
the umbrella of the Earth. But today, the ozone layer has been seriously damaged by mankind, the beginning of this century, a large number of human beings to use highly
stable synthetic compounds, such as air conditioners, refrigerators industry, solvents, aerospace with refrigerants, sprays,
cleaning agents containing chlorofluorocarbons compounded volatilization out of the ozone layer through a complex physicochemical process and the ozone chemical reaction
responses to the destruction of it. In 1984, scientists first discovered the ozone hole over the Antarctic, recently in the North
Polar over the ozone layer hole was also found, the ozone layer destruction of the direct consequences of the sun's ultraviolet radiation is to make a long tendency
directly into the harm to human beings and other organisms. Scientists have proved that: every 1% reduction in atmospheric ozone, ultraviolet radiation to the ground
surface increased by 2%, the incidence of skin cancer increased by about 4%, in addition to damage to the human immune
system, so that people suffer from cataracts and respiratory diseases increased likelihood of, at the same time, but also damage to marine life
hindered the growth of plants. Recent environmental science findings suggest that ozone layer depletion is also a significant factor in global climate change
.
17. What are the modes of photochemical smog pollution and their hazards?
Automobiles, factories (mainly car exhaust) and other sources of pollution into the atmosphere of hydrocarbons (HC) and
nitrogen oxides (Nox) and other first pollutants in the sunlight (ultraviolet) under the action of the photochemical reaction to generate
secondary pollutants. The mixture of primary and secondary pollutants involved in the photochemical reaction process creates
a smog pollution phenomenon called photochemical smog.
Photochemical smog has a complex composition, and their damage to humans and animals is mainly manifested in irritated eyes and mucous membranes, head
pain, respiratory disorders, worsening of chronic huffing and puffing inhalation diseases, and abnormal lung function in children.
18, what is the grade of malodor and its harm?
The bad odor is a floating in the air of fine substances, more harmful to human health are hydrogen sulfide, sulfur
alcohols, ammonia, methyl sulfur, formaldehyde, phenols and a variety of protein decomposition products. Odor by wind diffusion and transmission
broadcast, its intensity can be divided into six levels: 0 level, no odor; 1 level, barely feel a slight odor; 2 level, easy
feel a slight odor; 3 level, obviously feel the odor; 4 level, strong odor; 5 level, intolerable odor on
human respiratory, digestive, cardiovascular, endocrine and neurological system will have an impact. High concentrations of malodors can also
make contact with the occurrence of pulmonary edema and even death by asphyxiation. Long-term repeated stimulation by malodorous substances can also cause olfactory
fatigue, leading to olfactory malfunction.
19, sulfur dioxide pollution and its harm?
Sulfur dioxide (SO2) is a colorless gas with an irritating odor. When the concentration of SO2 in the atmosphere reaches 1-5ppm
, it irritates the respiratory tract and increases the resistance to airflow, triggering respiratory diseases, and children are more sensitive than adults. High
concentrations of SO2 can defoliate or even kill sensitive conifers, and cause acid rain.
20 What are the ways of lead pollution and its hazards?
Lead pollution is one of the more toxic types of heavy metal pollution. Lead pollution in the urban atmosphere mainly comes from automobile exhaust
Alkyl lead in the gas. Lead contamination of the human body through the respiratory tract and diet, through the respiratory tract intake absorption efficiency,
fast.
Lead has effects on all organ systems in the body, but the nervous system, blood and cardiovascular system are the main ones.
The most common are anemia, lead colic, and lead-poisoned hepatitis. In the nervous system the symptoms are vegetative neurasthenia (e.g.
headache, headache, weakness, irritability, poor sleep, memory loss, etc.) and polyneuritis.
21, polycyclic aromatic hydrocarbons pollution and its harm?
Hydrogen compounds containing more than two benzene are collectively referred to as polycyclic aromatic hydrocarbons. PAHs in the environment mainly come from
the combustion of coal and oil. Most of the PAHs generated by combustion are attached to soot particles and emitted into the atmosphere. PAHs are found in the exhaust of diesel and gasoline engines, as well as in the exhaust and wastewater from gas plants and asphalt processing plants, etc.
Polycyclic aromatic hydrocarbons (PAHs) are also present in the atmosphere. PAHs are also found in smoked food and smoke.
The harmful effects of PAHs on humans were discovered earlier, when scientists confirmed in 1915 that coal tar was
carcinogenic in rabbits. PAHs are not direct carcinogens, but are produced in the body by enzymes to produce final carcinogens.
The carcinogens combine with DNA or RNA to produce irreparable damage that leads to cancer.
22, electromagnetic wave pollution and its harm?
Electromagnetic waves are propagating alternating electromagnetic fields, according to the wavelength can be divided into long-wave, medium-wave, short-wave, ultra-short-wave
and microwave bands, according to the frequency can be divided into low-frequency, high-frequency, ultra-high frequency and ultra-high frequency. Electromagnetic radiation pollution is one of the important
important elements of environmental pollution. It harms people in an invisible way.
The higher the output power of the electromagnetic radiation source, the shorter the wavelength, the higher the frequency, the closer the source of radiation, the longer the contact
The longer the exposure to radiation, the higher the ambient temperature, the higher the humidity, the greater the impact on the human body and the harm. People who
long-term living in an environment contaminated by electromagnetic radiation, there will be fatigue, memory loss-based neurasthenia
disorder, agitation and menstrual disorders and other symptoms.
Microwave damage to the human body to the thermal effect of the main, to the visual organs of the most prominent harm. The use of "big brother
big" will change the human brain nerve and its blood flow aspects, over time, the human brain damage lesions.
23. What is toxic chemical pollution?
Toxic chemicals are chemicals that enter the environment to harm health and the environment through environmental accumulation, bioaccumulation, biotransformation, or chemical
reactions, or through exposure to the human body with a serious hazard and potentially dangerous
.
The hazards of most toxic
chemicals to the environment and human beings are not fully understood due to the increasing variety and quantity of toxic chemicals globally and the expansion of international trade. Their migration in the environment is also difficult to control, posing a serious threat to the
human environment; due to the fact that accidents caused by the leakage and transportation of toxic chemicals are characterized by their suddenness
strong, rapid and extensive pollution, and long duration, especially some malignant accidents resulting in serious personal casualties
and property damage; and due to the fact that hazardous wastes from toxic chemicals constitute a long-term potential threat to the human environment. Waste on the human environment constitutes a long-term potential
in the harm, toxic chemicals has become an important global environmental issues, caused by the world's attention
View. In recent years, some developed countries have transferred some of their wastes to the third world, and although there has been the Basel
Cublication Printing, it is still prohibited, and some developed countries in Europe and the United States have been transferring hazardous wastes to developing countries
often occurring.