Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Water pollution is a phenomenon where rivers, lakes, seas and groundwater are contaminated with toxic substances in plant protection drugs, industrial wastes, domestic wastes, etc. great fruit to the lives of humans and natural creatures. There are many causes of water pollution, be it heavy rain, melting snow, storm winds, floods that accidentally bring a dirty amount of waste, dead organisms into the water environment, or volcanic eruption, sea level rise. However, human is the main factor leading to water pollution through industrial, domestic, agricultural, ... wastes into the water environment. We all know that just a sheet of paper, a carton of milk or a plastic bag is discharged into the pond environment, causing water pollution, landscape loss, and pipeline congestion. In addition, factories and enterprises are increasingly developing to serve the needs of production and consumption of people, making the source of wastewater soak up into the groundwater, causing serious water pollution. The consequences are very large, you probably do not know, up to 70% of the human body is water. People need clean water to serve daily activities. However, with the current situation of water pollution, human is the agent and can "RECEIVE DAY" is real. Because, the consequences of water pollution are huge: heavy metal contamination; Contamination of toxic organic compounds, pathogenic bacteria in water, especially wastewater. In order to effectively deal with water pollution, these solutions need to be formulated and implemented at all levels, from global, national to local. Hope you will join hands to overcome and keep the water source clean.
Water pollution is the pollution of bodies of water, such as lakes, rivers, seas, the oceans, as well as groudwater. It occurs when pollutants reach these bodies of water, without treatment. Waste from homes, factories and other buildings get into the water bodies.
Water pollution is a problem for the species and ecosystems there. It affects plants and organisms living in the water. In almost all cases the effect is damaging not only to individual species and populations, but also to the wider biological communities. The color is usually green or brown but normal water can be blue.
Agriculture is one of the major sources of water pollution, because the fertilizers given to the crops for better growth are washed into rivers and lakes, which in large amounts pollute the water.
There are many chemicals that are naturally found in these bodies of water but today it is polluted by nitrates, phosphates, oil, acid from acid rain, and debris like sediments, fallen logs and so on.
I.water pollution
Artificial causes from people and production affect the water environment
1. From human beings
Every day there is a large amount of domes waste into the environment without treatment, in addition to increasing population, the amount of domes waste also increases. In developed countries, the population growth rate is about 5% while the population growth rate in developing countries is over 2%.
Domes wastewater is waste water generated from households, hospitals, hotels and schools, containing wastes during human daily life and sanitation. The basic composition of domes wastewater is organic biodegradable organic substances (carbohydrates, proteins, oils, nutrients, solids. Depending on living standards and lifestyle, the amount of wastewater as well as the load The substances in each person's wastewater in a day are different, and the higher the living standard, the higher the amount of waste water and the discharge load, so the disease has conditions to spread and pollute the environment.
2. From agricultural production
Agricultural activities such as animal husbandry, animal urine, unprocessed and environmental uneaten food and other agricultural activities. Pesides, fertilizers from rice fields, melons, gardens, vegetables contain toxic chemicals, can contaminate groundwater and surface water.
In the process of agricultural production, most farmers use pesides three times the recommended dose. Not only that, farmers also use banned pesides such as Thiodol, Monitor ... In the process of fertilizing, spraying, farmers do not equip with labor protection tools.
Currently, the use of chemical fertilizers and chemical pesides is rampant in agriculture, causing water sources to be affected. Quantification of residues will sink into the aquifers that affect the amount of water.
Most farmers do not have storage facilities for medicines and medicines when they have not been used and are stored everywhere, including near cafeterias and drinking water sources. Most of the peside bottles used after being discarded were immediately thrown into the fields, the rest were collected for sale.
3. From industrial production
Waste and wastewater, from industrial production activities due to the speed of urbanization, industrialization and development have led to the establishment of industrial parks, thus the amount of waste and wastewater of activities The industry is growing and has not been thoroughly treated directly into the environment or rivers, water sources affect the current water quality.
Natural causes affect the water environment
Any water quality degradation phenomenon causes water pollution. Water pollution due to rain, snow, flood ... or by the casca of living organisms' activity not to mention their corpses. Trees and organisms die, they are decomposed by microorganisms into organic matter. A part will infiltrate into the ground, then penetrate deep into the groundwater, pollute, or follow the flow of groundwater into the big stream.
Flooding can cause water to lose its purity, stir up contaminants, grime in sewers, carry many toxic waste from garbage dumps, and carry on with previously stored substances. .
Prolonged flooding can be more heavily polluted by chemicals used in agriculture, industrial waste, chemical pollution ... Water pollution due to natural factors (volcanoes, storms, floods, erosion ...) may be very serious.
The deterioration of water quality may be due to geological characteriss of water sources such as water on acid sulphate soils often contain a lot of iron, aluminum, water taken from the ground often contains a lot of calcium ...
Measures to overcome the causes of water pollution
People should become more aware of their living environment protection, enterprises should have tanks to treat waste water before being discharged into the environment. The authorities and mass organizations need to regularly inspect companies to avoid the situation of profit that companies do not comply with environmental protection laws.
In addition, people should also protect their family's health by a family water well filter system, a water treatment machine to completely remove contaminants, toxic substances and heavy metals. .. create pure water to drink water, directly without cooking.
The above are the causes of water pollution today, hope that through this arle, people can be more aware to protect the water environment more clean and safe. Because clean water is essential to a healthy life.
II. Air pollution
Causes of air pollution.
Air pollution due to natural factors:
Due to natural phenomena: volcanoes, forest fires, dust storms, or decomposition processes, decaying keratosis - natural plants ... This is an objective cause so it is difficult to predict and prevent.
Air pollution due to human factors
+ Industry: This is the largest source of pollution caused by humans. The process of pollution is the burning of fossil fuels such as coal, oil and gas, creating toxic gases (CO2, CO, SO2, NOx, unburnt organic substances: soot, dust ). Industrial sources are highly toxic, concentrated in a small space, and depending on the scale of production and the fuel used, the amount of toxic and toxic substances will be different.
+ Transportation: This is also a major source of pollution to the air, especially in urban areas and densely populated areas. The process of burning engine fuel creates toxic gases that affect the air such as CO2, CO, SO2, NOx, Pb, CH4 ...
+ Activities: Mainly due to cooking activities that use fuels to create harmful gases that pollute the local households and surrounding households.
Consequences of air pollution
For animals - plants.
+ Air pollution causes harmful effects to all organisms.
+ Sulfur dioxide, nitrogen dioxide, ozone, fluorine, lead ... directly harm plants when entering stomata, damaging the system to reduce drainage and reduce disease resistance.
+ Most fruit trees are very sensitive to HF. When exposed to a concentration of HF greater than 0.002 mg / m3, the leaves are burnt spots, deciduous.
+ Earth's warming due to the greenhouse effect also causes changes in plants and animals on Earth.
+ Acid rain also indirectly affects plants and lacks food Ca and kills soil microorganisms. It causes Al ion to be released into the water to damage the roots (absorbing feathers) and reduce the absorption of food and water.
+ For animals, especially pets, fluoride causes more disasters. They are poisoned by direct inhalation and through the food chain.
+ Acidic air pollutants will combine with water droplets in the cloud to make water acidic. When the water drops on the ground, it will harm the environment: killing trees, animals, fish, etc. Acidic water also changes the nature of water in rivers, streams, etc. harming the births. living things under water.
For man.
Dust:
+ Harmful effects of dust depend on the nature (composition) of dust, dust concentration, dust parle size, contact time and personal response.
+ Dust into the lungs causes mechanical irritation, pulmonary fibrosis leading to respiratory diseases.
+ Dust can cause eye, skin and blood sugar diseases and other body systems (Dust enters the body and dissolves in blood and body fluids), cardiovascular disease ...
+ Dust can cause cancer: dust containing toxic ingredients, asbestos dust ...
Dioxide Sulfur (SO2) and Nitrogen Dioxide (NO2):
Sulfur Dioxide (SO2).
+ Sulfur Dioxide is a gas formed by oxidation of sulfur (S) when burning fuels such as coal, oil, products of oil, sulfide ore, etc. SO2 is a gas that causes strong respiratory irritation, when inhaled. breathing of SO2 gas (even at low concentrations) can cause spasm of the bronchial straight muscles. Large concentrations of SO2 can cause increased mucus secretion in the upper respiratory tract mucosa and bronchial air branches. SO2 affects the function of the lungs, causing pneumonia, chronic bronchitis, causing cardiovascular disease, hypersensitivity in people with asthma, ...
+ SO2 poisoning through the skin reduces alkaline reserves in the blood, eliminates ammonia to the urine and releases saliva.
+ General toxicity of SO2 expressed in disorders of protein and sugar metabolism, lack of vitamins B and C, inhibition of oxidase enzymes.
Nitrogen Dioxide (NO2):
+ Nitrogen Dioxide (NO2): is a brown gas, produced by Nitrogen oxidation at high temperature. NO2 is a dangerous gas, has a strong effect on respiratory organs especially in susceptible groups such as children, the elderly, asthma sufferers. –If contact with NO2 will damage the lung mucosa, increase the risk of respiratory diseases, damage of lung, eye, nose, and throat functions, etc.
Carbon monoxide (CO)
+ Carbon monoxide (CO) combined with hemoglobin (Hb) in the blood to be a stable compound, cacboxy hemoglobin (HbCO), reduces blood oxygen transport capacity, leading to lack of oxygen in the blood ....
Ammonia (NH3)
+ NH3 is a toxic gas that can strongly stimulate the nose, mouth and respiratory system.
+ Exposure to NH3 at a concentration of 100mg / m3 in a short period of time will not have long-term consequences, but if exposed to NH3 at a concentration of 1500-2000 mg / m3 for 30 minutes, it will be dangerous to live.
Hydrogen sulfide (H2S).
+ H2S enters the body through pphooir will be oxidized to sulfate. Low toxicity compounds will not accumulate in the body. About 6% of the absorbed gas will be excreted through exhaled air, the rest after the metabolism is excreted in the urine.
+ At low concentrations, v stimulates on eyes and respiratory tract.
+ Breathing large amounts of H2S mixture will cause a sudden lack of oxygen, which can lead to death from suffocation.
+ Signs of acute poisoning:
vomiting, gastrointestinal disorders, diarrhea, dry and foul-smelling nasopharynx, eyelid- eyes, ocular conjunctivitis, purulent secretion and vision loss.
+ Regular exposure to H2S at levels below the level of acute toxicity can cause chronic poisoning. Symptoms can be: weakness, nervous system disorders, digestive system, insomnia, chronic bronchitis, ...
Volatile organic compounds (VOCs)
+ Volatile organic compounds (VOCs) include many organic chemicals in which the most important are benzene, toluene, xylene, .. VOCs can cause acute toxicity if exposed at high doses, causing inflammation of the respiratory tract. absorption, gastrointestinal disorders, neurological disorders, hematological disorders, causing liver - kidney damage, causing skin irritation, ... and is the cause of myelosuppression, blood cancer.
Lead (Pb):
Lead (Pb): exhaust smoke from the engine of vehicles involved in traffic contains a certain amount of lead. In addition, lead can be generated from ore mines, from factories producing batteries, synthe plass, paints, chemicals, etc. Lead enters the body through respiratory, food, drinking water, and through skin, through breast milk, etc. Lead will accumulate in the bones and red blood cells causing bone marrow disorders, joint pain, nephritis, hypertension, cerebral complications, poisoning of the central and peripheral nervous system, Red cell rupture causes anemia, causing kidney dysfunction. Pregnant women and children are very susceptible to the effects of lead (causing miscarriage or death, reducing intelligence, ...).
Radon gas.
Radon gas is produced by decaying uranium in nature, which is a heavy gas so it usually exists in the air layer close to the ground. In nature, radon is found in rocky soil, coal slag, construction material dump, in mud. Radon can cling to small dust parles, penetrate the body through the respiratory tract or penetrate the skin, through open wounds that cause lung cancer, leukemia, etc.
For properties
+ Making metal rust.
+ Corrosion to concrete.
+ Abrasion, decomposition of the product surface.
+ Causing discoloration and damage to paintings.
+ Reducing plas strength and discolouration of fabric fibers.
+ Reduce durability of paper, rubber, tanning.
For global
+ Acid rain
+ Greenhouse effect
+ Ozone layer depletion
+ Temperature change.
Remedies
Technical measures:
+ Replace outdated machines, outdated technology lines, causing much pollution by modern, less polluting technology chains.
+ Replace burning fuel from coal and fuel oil by using electricity to prevent air pollution by burnt and SO2.
Planning measures:
+ Minimizing the construction of industrial parks in export processing zones in the city, only retaining enterprises directly serving people's daily needs.
+ Encourage people to travel by public means to minimize congestion and traffic means, thereby reducing the density of dust and waste caused by the combustion of fuel and oil in the air. , especially during peak hours.
+ Create large areas of green trees in the city, set up strips of green trees connecting different areas of the city, especially in areas and streets with many means of passing and happening. congestion.
Some vehicles overcome air pollution
Air purification by biological method
Biofiltration is a relatively new treatment for pollution, which is an attractive method for handling bad odor gases and low concentrations of volatile compounds.
The common shape of a biological filtration system is a big box, some systems can be as big as a basketball court, some systems can be as small as a yard yard (0.76 m3). The main principle of the treatment system is to allow bacteria to come into contact with pollutants in the exhaust gas. This exhaust filter system is a place to store filter materials and breeding grounds for microorganisms. In this system, microorganisms will form a biofilm, which is a thin, moist membrane surrounding filter materials.
During the filtration process, the exhaust gas is pumped slowly through the filtration system, the pollutants in the exhaust gas are absorbed by the filter materials. The polluting gases will be adsorbed by biofilms, where microorganisms will decompose them to create energy and by-products of CO2 and H2O by the following equation:
Organic pollutants + O2 CO2 + H2O + heat + biomass.
Waste gas treatment by biotechnology
Biofilter technology (biofilter) is an emissions treatment method with low investment cost, low cost and environmentally friendly operation, it is a suitable method for handling odors and gases. Volatile organic compounds with low concentrations such as animal feed and cassava starch factories
Air purifier
Based on the principle that charged parles will attract each other, the machine uses technology to emit negative charges into the air, neutralizing the symmetrical charges as harmful positive ions in the environment and creating effects to attract dirt, bacteria, mold ... These negative ions also adhere to toxic parles in the air and positively charged electrosta membrane in the machine will attract and hold these parles.
In closed rooms where,
Many equipment such as computers, printers, televisions, neon ... are devices that emit many positive ions causing harm to the body, air purifiers will provide negative ions and air conditioners.
Gauze mask:
Activated carbon masks and deodorants have the following effects:
+ Preventing entry into the respiratory tract of microscopic dust parles and other pollution wastes.
+ Filter odor, chemicals, gasoline smell, photochemical smoke, black smoke, pollen. Prevent dust, toxic gases such as CO, SO2, NO2, H2S, NH3 ....
+ Protecting respiratory system, limiting allergic rhinitis caused by air pollutants.
Artificial light is an important factor that contributes effectively in the process of socio-economic development. And in fact, the industrial society has been too dependent on artificial light because it is used to illuminate public places, offices, factories, residential areas ... to meet and serve activities. However, when light is not used effectively, causing excessive light is the cause of pollution. light.Based on the characteriss of the sources and the object affected, light pollution is classified into the following categories: light intrusion, light abuse, glare, mess and light. usurp the sky.
Intrusion light occurs when light reflects on unwanted or unwanted areas. Such as street lights shining into the windows of roadside apartments, the result could be insomnia for those who live in them.Bright light is the result of the opposite of the light and dark areas in the view. When bright light is shining directly into the eyes of pedestrians will lose visibility in the night and this problem is especially serious for traffic safety.
Light abuse is excessive use of light, causing waste. The main cause of this problem is not turning off the light when not needed or inappropriate lighting design makes the use of light larger than necessary or the light does not focus on the necessary area.The light is cluttered due to the excessive use of multiple light sources. At the same time, they are arranged to create interwoven light streams. Typically, there are too many advertising lights on the streets. This is also a cause for pedestrians to easily lose focus and can lead to accidents.
Light appropriating the sky usually occurs in densely populated areas, especially in modern urban areas. All the light from different sources reflects off the night sky, causing the area to shine brightly when viewed from afar. This problem especially affects astronomers when observing stars.
1. Write about a natural disaster you have read about.
The most destructive disaster that I have experienced was the flood in 2012, in Thanh Hoa province. It had been raining heavily for many days. All homes, trees and animals were flooded. The water got to the roof of houses. Damage was caused to property and people. Many people were injured and died. Rescue workers helped people trapped in the flooded houses and they brought people who were left homeless to safe place. My house was flooded but we had been evacuated before. Although the time has gone by, I still can’t forget that terrible disaster.
2. Write a passage describing the schedule for your visit (Choose 4 activities that you would like to do in a 2 day visit to Washington D.C., the capital of the USA.)
This is the schedule for our group’s 2-day visit to Washington DC. On the first day, we plan to expore the city on a hop-on-hop-off trolley at 9 am. Then at 1: 00 we are visiting the White house , where the President of the USA lives. On the second day, we are taking the shuttle bus to visit the National Children’s museum at 8:00. Then at 14-00 we plan to cycle on bike trails in Nationa park.
Tham khảo :
Air pollution is a major change in the composition of the atmosphere, mainly from smoke, dust, soot, steam or air makes strange gas is not clean, there was a smell coming, reduced visibility, caused climate change, pathogenic for humans and creatures.
Air pollution caused more than 3 million people die prematurely every year, it threatens virtually all of the big city dwellers in the developing countries. According to Fox News 80% of cities in the world can not meet the standards of the World Health Organization (WHO) on air quality, which is mainly concentrated in poor countries. WHO said the level of urban air pollution worldwide has increased by 8% despite improvements in some areas. This leads to the risk of stroke, heart disease, lung cancer and a variety of respiratory problems.
Air pollution: Definition: air pollution is a mixture of solid particles and gases in the air. CAuse: have a two main cause : The first is from nature as acid rain. The second is from people acting as vehicles emitting dust and smoke. Effect:harmful to humans , making animals and plants unable to live, causing serious illness. Sollution: planting trees, improve human working machines, educating people on mesures to raise awareness of environmental protection
Fresh water is the most important source of life on the earth. Any living thing may survive without food for days however it is impossible to imagine life without water and oxygen. The ever increasing human population enhances the demand of more water for purposes like drinking, washing, performing industrial processes, irrigating crops, arranging swimming pools and other water-sports centres. Water pollution is done by the people of all over the world because of increasing demands and competitions of luxuries life. Waste products from many human activities are spoiling the whole water and decreasing the amount of oxygen available in the water. Such pollutants are altering the physical, chemical, thermal, and biological characteristics of the water and adversely affecting the lives inside as well as outside the water.
When we drink the polluted water, harmful chemicals and other pollutants goes inside our body and deteriorates all the body organs functioning and puts our lives in danger. Such harmful chemicals also disturb the lives of animals and plants greatly. When plants absorb dirty water through their roots, they stop growing and die. Thousands of seabirds are killing because of the oil spilling from ships and industries. High level of water pollution is done due to the chemicals coming out of the agricultural usage of fertilizers, insecticides and pesticides. The effect of water pollution varies from place to place upon the type and amount of water contamination. The degradation of drinking water needs an urgent basis prevention method which is possible by the proper understanding and support from the end of each and every person living on the earth.