Natural disasters/natural hazards "natural disasters" are abnormal phenomena in nature on which human beings depend, and the harm caused by natural disasters to human society is often shocking.
Among them are earthquakes, volcanic eruptions, mudslides, tsunamis, typhoons, floods and other sudden disasters; There are also gradual disasters, such as land subsidence, land desertification, drought, coastline changes, etc., which can only gradually appear in a long time; There are also environmental disasters caused by human activities such as ozone layer change, water pollution, soil erosion and acid rain. There is a complex relationship between these natural disasters and environmental damage.
It has become the common theme of the international community to scientifically understand the occurrence and development of these disasters and minimize their harm. Natural variations on the earth, including those induced by human activities, occur all the time. When this mutation brings harm to human society, it constitutes a natural disaster.
Because it has brought different degrees of damage to human production and life, including the relationship between man and nature through labor and the interpersonal relationship related to it. Disasters are negative or destructive.
Therefore, natural disasters are a manifestation of the contradiction between man and nature, with the dual attributes of nature and society, and are one of the most severe challenges faced by mankind in the past, present and future. The main sudden natural disasters in the world are: drought, flood, typhoon, storm surge, freezing injury, hail, tsunami, earthquake, volcano, landslide, debris flow, forest fire, agricultural and forestry diseases and insect pests, etc.
There are many kinds of natural disasters in China. Earthquake, typhoon, rainstorm, flood, waterlogging, high temperature, lightning, fog, haze, debris flow, landslide, tsunami, road icing, tornado, hail, snowstorm, collapse, land subsidence, sandstorm, etc. It occurs in all parts of the country and local areas every year, causing extensive damage or devastating blows in local areas.
China is the country with the largest variety of natural disasters in the world, among which there are seven natural disasters that have the greatest impact on China. 1, meteorological disasters There are more than 20 kinds of meteorological disasters, mainly including the following: (1) rainstorm: mountain torrents, river floods and urban water accumulation; (2) Rain and waterlogging: waterlogging; (3) Drought: drought in agriculture, forestry and grassland, and water shortage in industry, cities and rural areas; (4) Dry-hot wind: dry-hot wind and foehn wind; (5) High temperature heat wave: extreme heat and high temperature, human diseases, burns, and crop ripening; (6) Tropical cyclones: gale, rainstorm and flood; (7) Cold damage: crops, livestock and fruit trees are harmed by strong cooling and low temperature; (8) Freezing injury: frost, crop and livestock freezing injury, water pipes and oil pipes freezing injury; (9) Freezing rain: wires, branches and roads are frozen; (10) Freezing: rivers, lakes and seas freeze, and roads freeze after rain and snow; (1 1) Snow damage: snowstorm, snow; (12) Hail disaster: destroying crops and houses; (13) Wind disaster: falling trees, reversing houses, reversing cars and reversing boats; (14) Tornado: local destructive disaster; (15) Lightning: lightning casualties; (16) Continuous rain (lewd rain): it is not conducive to crop growth and development, grain mildew, etc. (17) dense fog: human diseases and traffic jams; (18) low-altitude windshear: aviation accident; (19) acid rain: crops are harmed.
2. Marine disasters Marine disasters mainly include the following types: (1) storm surge: including typhoon storm surge and temperate storm surge; (2) Tsunami: There are two types: long-range tsunami and local tsunami; (3) Waves: including wind waves, swells and nearshore waves, which are divided into typhoon waves and cyclone waves; (4) seawater; (5) red tide; (6) Coastal disasters: such as coastal erosion, landslides, land salinization and seawater pollution. (7) the harm of El Nino. 3. Flood disaster (1) rainstorm disaster; (2) mountain torrents; (3) snowmelt flood; (4) ice flood; (5) dam-break flood; (6) Debris flow and cement flood.
4. Earthquake disaster (1) tectonic earthquake; (2) Collapse earthquake; (3) mine earthquake; (4) Reservoir earthquake, etc. 5. Crop biological disasters (1) Crop diseases: there are mainly more than 240 kinds of rice diseases, 50 kinds of wheat diseases, 40 kinds of corn diseases, 40 kinds of cotton diseases and many diseases such as soybeans, peanuts and hemp; (2) crop pests; There are mainly 252 kinds of rice pests, more than 0/00 kinds of water wheat pests, 52 kinds of corn pests, more than 300 kinds of cotton pests and various other crop pests. (3) Crop weeds: about 8,000 species; (4) Rat damage. 6. Forest biological disasters (1) Forest diseases: 29 18 species; (2) Forest pests: 5020 species; (3) Forest rodents: 160 species.
7. Forest Fire The Natural Disaster Comprehensive Research Group of the State Science and Technology Commission, the State Planning Commission and the State Economic and Trade Commission divides natural disasters into seven categories: meteorological disasters, marine disasters, flood disasters, geological disasters, earthquake disasters, crop biological disasters, forest biological disasters and forest fires. However, disasters closely related to our daily life mainly include: 1. Natural variation of geological disasters and human activities may lead to changes in geological environment or geological body. When this change reaches a certain level, landslides, mudslides, land subsidence, ground collapse, rock swelling, sand liquefaction, land freezing and thawing, soil salinization, land desertification, earthquakes, volcanoes, geothermal disasters and other consequences will do harm to human beings and society.
This phenomenon is called geological disaster. Geological disasters also include derivative disasters.
(1) Debris flow. Debris flow is a special torrent containing a lot of sediment and stones in the valley under the stimulation of heavy rain and melting of snow and ice.
The formation of debris flow: the following three conditions must be met at the same time: steep terrain is convenient for water collection and water collection; Abundant loose matter; There is a lot of water in a short time. The material composition of debris flow can be divided into three categories: debris flow consists of a large number of cohesive soil, sand particles and stones with different particle sizes; Mainly cohesive soil, containing a small amount of clay particles and stones, with high viscosity, which is called debris flow when it becomes thick mud; Water-rock flow consists of water, sand and stones of different sizes.
Hazard of debris flow: hazard to residential areas; Harm to roads and railways; Harm to water conservancy and hydropower projects; Damage to mines; (2) landslides. The rocky mountain on the landslide is very fragile under the action of gravity for various reasons.
2. Essay on Natural Disasters
Natural disasters, including man-made disasters, are man's greatest enemies.
There are many natural disasters, such as earthquakes, acid rain, greenhouse effect and typhoons. Man-made disasters include fire, soil erosion and so on.
As early as ancient times, people had no awareness of prevention, and they all prayed to God and Buddha for peace. With the development of society, people know how to protect themselves with scientific and practical methods and reduce the threat of disasters to life.
This article will tell you how to use scientific methods to prevent earthquakes and reduce disasters, protect yourself and protect your home. Earthquake prevention and disaster reduction, natural disasters, beautiful homeland, awareness of prevention, man-made disasters, according to the survey, there are many major earthquakes in many places in China, such as Dali earthquake in Yunnan/KOOC-0/5/KOOC-0/4, Haicheng earthquake in Liaoning/KOOC-0/975, Qiongzhou earthquake in Hainan/KOOC-0/605, and Qiongzhou earthquake in Hainan/KOOC.
In fact, some disasters can be prevented. Before the earthquake, there will be some signs.
For example, domestic animals such as horses will break free from the reins and run wildly outside; Hibernating snakes will come out of their holes; Bees will fly around; Dogs will bark, and some livestock will run around in circles; Rats move in groups ... these omens can let people know in advance that there will be an earthquake. If these animals are found to have these abnormal phenomena, we must first distinguish between the true and false, and then report to the Seismological Bureau to prevent them from leaving early. An earthquake doesn't mean you will die. In fact, there are many ways to save yourself.
For example, you are trapped under the ruins after the earthquake. Don't move blindly at this time, be calm. First, take out your hand and move the ruins slowly. First keep breathing smoothly, then try to breathe and call someone to save you. If you are at home during the earthquake, you must immediately enter a hard small room that has not collapsed to avoid injury.
Also, stick it on a solid wall or squat at the door, and survive after the house collapses to avoid being hurt. If you are in the wild, you must avoid steep cliffs to prevent yourself from falling down the mountain.
There is also the need to prevent landslides, so as not to slide down. If you are at school, you must obey the teacher's instructions, hide under the desk and pay attention to protecting your head. If you go to physical education class, avoid tall buildings and don't get hurt.
If you are in the cinema, you should hide under the viewing chair to avoid the shock, avoid the lights hanging on the ceiling and the hanging objects of air conditioners, protect your head with things, and follow the instructions of the commander to evacuate the scene. There was an earthquake in the shopping center. Avoid glass cabinets, commodities, billboards, lights and other items.
If you are on the bus, you should hide under the chair or squat down, keep your center of gravity stable and grab the handrail. Other natural disasters are not as inevitable as earthquakes, and sometimes they can be completely controlled.
Acid rain is called "death in the air" because the waste gas (sulfide) emitted by people's factories floats into the air. When it rains, it turns into acid rain with the rain. Acid rain will cause the lake to turn sour and kill fish and shrimp; The forest is getting old; Farmland becomes barren; Once dripping on cultural relics and precious calligraphy and painting, it will be corroded immediately ... It can be seen how harmful acid rain is to people! Greenhouse effect refers to an effect that gases in the atmosphere absorb infrared rays, which leads to an increase in temperature.
Its harm is not small, it will make many people lose their lives, especially the elderly and children. The greenhouse effect will make people suffer from lung diseases such as asthma, and it will also cause many diseases, such as encephalitis and high fever.
It will also cause droughts, floods, reduced grain production and serious property losses in many places. There are also many natural disasters, many of which are human's own "masterpieces".
So have this knowledge and don't hurt yourself. Not only natural disasters, but also man-made disasters.
Such as fire, debris flow, soil erosion, etc. It is human beings who cut down trees themselves and cause unnecessary losses. So, I suggest you do this: 1. Protect forests, plant trees and protect water and soil.
This factory should not emit too much exhaust gas, but should use inexhaustible solar energy. In order to protect the ozone layer, cars should not emit exhaust gas.
4, be careful with fire, don't throw cigarette butts. 5. Learn more about earthquake prevention and disaster prevention, and have awareness of prevention.
6. Save water and cherish every drop of water. If these points are done well first, the occurrence of disasters will be reduced, or many people's lives will be saved once disasters occur.
Protecting our home, the earth, is to protect ourselves. Let's take action to prevent disasters and make the earth's tomorrow brighter and brighter.
3. Natural disasters in China
The heavy rain in Xinjiang caused a disaster, and the direct economic loss in Yili area reached 654.38+0.6 billion yuan; 17 July, Chongqing was hit by the strongest thunderstorm in 1 15 years, and the mountain city turned into a water city, with traffic in the main city almost paralyzed and 55 people killed. The next day, there was a rainstorm in Jinan, killing 34 people; Affected by cold and warm air, from the early morning of August 7, there was heavy rain to heavy rain in Liaoning. As of August 8, the meteorological department has continuously issued 18 rainstorm warning signal; According to the news released by Hubei Provincial Department of Civil Affairs on August 9, since the flood season this year, the flood disaster in the province has affected14.95 million people, including 79 deaths and 2/kloc-0 missing. ...
In sharp contrast, the days of continuous high temperature in Jiangnan and South China all exceeded 10, and even a once-in-50-year drought occurred in Changsha, Hunan. According to the data of relevant departments, up to now, 245 small reservoirs and 64,000 mountain ponds have dried up, and 748 streams and rivers have been cut off.
Faced with this phenomenon, some people describe it this way: half is seawater and half is flame-and those who live in dire straits are undoubtedly victims everywhere. A netizen in Changsha complained on the forum that he had not taken a bath for three days. "It takes four or five hours to pump half a tank of water from the well." What makes him even more depressed is that "the fight for water happens every day."
Together with the Ministry of Finance, 435 million yuan of disaster relief funds were allocated to the affected provinces 26 times. The relevant person in charge of the Ministry of Civil Affairs recently revealed in an interview with reporters. In contrast, the losses caused by extreme weather are even greater. On August 7th, the announcement of national natural disasters issued by the Ministry of Civil Affairs showed that from June 5438 to July this year, there were 466 natural disasters in China, the frequency of which was much higher than that of the same period in 2006, especially extreme weather and climate events caused very serious casualties and economic losses to the affected areas.
As of July 3 1, there were 280 million people affected by various natural disasters, 279 people died/kloc-0, 239 people were missing, and 6153,000 people were resettled urgently. The direct economic loss caused by the disaster is11010.8 billion yuan.