1. Global warming and urban "heat island"
Global warming will cause changes in precipitation and dry and wet conditions in various regions of the world, which in turn will lead to changes in the economic structure of countries around the world. Mid-latitude areas will become dry because of the strong evaporation caused by climate warming, and now the agricultural developed areas will degenerate into grasslands; High latitudes will increase precipitation due to warming, and temperate crops will be able to settle here. But as far as the world is concerned, the negative impact of climate warming on the world economy is the main one, and only some local areas benefit.
The temperature in the city is much higher than that in the suburbs, just like a warm island. Beijing, the largest city in China, is 9.6 degrees higher than that in the suburbs, and the maximum temperature difference between Shanghai and the suburbs is 6.8 degrees. The reason for the urban "heat island" effect is that the urban population is concentrated and increasing, and the industry is developed. Residents' lives, industrial production and automobiles consume a lot of fuels such as coal, oil and natural gas every day, releasing a lot of man-made heat. Another reason is that buildings made of concrete, stone and brick in the city and pavements, sidewalks and squares paved with asphalt, cement, ceramics and stone have replaced the natural ground covered with vegetation and crops. They have low reflectivity, high heat capacity and absorb a lot of solar energy.
2. Rapid extinction of species
Due to the influence of human activities, especially people's deforestation, grassland reclamation and environmental pollution, the habitat or growing place of wild animals and plants has been lost and the living environment has deteriorated. In addition, people have hunted wild animals indiscriminately, which has made many kinds of wild animals and plants in the world extinct or endangered.
The Red Alert List of Endangered Species published by IUCN in 1996 shows that 24% of the 4,5 existing mammals in the world are facing extinction, while 12% of the 9,5 existing birds are about to become extinct. Among about 1, known woody plants, about 6% are endangered, of which about 1, are in danger. Every 24 hours, 15 ~ 2 biological species bid farewell to the earth forever. According to data, the extinction rate of species on the earth is 1 million times faster than the formation rate. China is a country rich in wildlife, but the biodiversity of China is facing a serious threat. Among angiosperms, there are 1 endangered species and 28 extremely endangered species; There are 63 endangered species and 14 critically endangered species of gymnosperms, and one species has been extinct. There are 433 species of vertebrates threatened.
3. There is a serious shortage of water resources in the world
With the rapid growth of the world population, the water consumption is increasing, and the water pollution is becoming more and more serious, so many fresh water resources that could have been
utilized are destroyed. At present, 6% of the world's regions are facing water shortage, 2% of the population have difficulty in getting clean water and 5% of the population have no access to sanitary water. Many countries are short of water. In recent years, many countries in the United States, Japan and Eastern Europe have experienced the problem of water shortage. Even Russia and Canada, which are rich in fresh water resources, are threatened by water shortage in some areas. Some countries in Africa have been suffering from drought for years, and water shortage directly threatens people's survival. It is predicted that the water crisis will become the "most controversial issue" in cities in the 21st century.
4. Global environmental problems
Environmental problems are not only the problems of a certain country or a certain region, but have now developed into global problems. When an environmental problem occurs in a region, the scope of its influence will often greatly exceed that of the region. For example, with the movement of the atmosphere, acid rain can affect far away areas; The pollution of the upper reaches of international rivers will affect the whole river basin ... The problem of environmental pollution is becoming more and more serious, and waste gas, waste water and even solid waste can be transferred from one country to another. Some environmental problems even affect the survival and development of all mankind. For example, the destruction of the tropical rain forest in the Amazon basin will have an impact on the global climate; The increase of CO2 concentration in the atmosphere and the destruction of the ozone layer threaten all mankind.
5. China's resources
In terms of the total amount of natural resources, China's total amount of many kinds of natural resources is in the forefront of the world, and it can be called a
resource country with vast territory and abundant resources. However, China has a large population, and the per capita possession of various resources is very small. The relative shortage of per capita resources is the basic national condition of China's resources.
China's cultivated land area ranks fourth in the world, and its per capita cultivated land is only equivalent to 1/3 of the world's per capita value; The forest area ranks sixth in the world, and the per capita forest possession is only 1/5 of the world's per capita value; China's total mineral resources reserves rank third in the world, and its per capita possession is equivalent to 3/5 of the world's per capita value ... And with the continuous increase of China's population, the per capita possession of various resources will continue to decline. The relative shortage of per capita resources has become a restrictive factor for China's economic development and the improvement of people's living standards. China's resources still have the characteristics of uneven regional distribution. For example, China has more water resources in the south and less in the north, but less cultivated land resources in the south and more in the north, which is not conducive to the development of agriculture.
6. Air pollution
Scientists have found that at least 1 kinds of air pollutants are harmful to the environment, among which
sulfur dioxide, nitrogen oxides, carbon monoxide and hydrofluorocarbons are more harmful to human health. Air pollutants seriously harm people's trachea, lungs and other respiratory systems.
The main ways to cause air pollution are the waste gas and dust emitted by industrial production and vehicles, and the dust particles emitted by industrial production also adsorb many toxic and harmful substances. These pollutants will also undergo various chemical reactions in the atmosphere, generating more pollutants and forming secondary pollution. Sulfur dioxide is one of the most common air pollutants, which can form sulfuric acid smoke and even acid rain through reaction in the atmosphere. Nitrogen oxides, carbon monoxide and hydrocarbons are also common pollutants in the atmosphere. They undergo photochemical reactions in the sun and can form photochemical smog.
The accumulation of air pollutants in the air leads to the decline of air quality, which directly harms human health, warms the global climate and destroys the ozone layer; Pollutants drift with the wind, even affecting agriculture, forestry and animal husbandry. The United States loses hundreds of millions of dollars every year, and China's losses are also quite serious.
7. Understanding sandstorms
Sandstorms, also known as black storms, are a natural phenomenon that occurs in desert areas. A large amount of quicksand in desert area is the sand source of sandstorm, and the strong wind in spring is the strength of sandstorm.
In the past century, due to excessive reclamation, overgrazing and deforestation, the surface vegetation has been seriously damaged, and a large area of land has become bare. With the continuous acceleration of desertification, the scope of sandstorms has gradually expanded and the degree of sandstorms has gradually increased. In the spring of 2, the capital Beijing was hit by sandstorms eight times in a row. According to scientists' calculations, it will take about 2 years to scrape off the 18 cm thick topsoil on a grassland. If the grassland is reclaimed into farmland, it will only take 49 years; If it is bare land, it only takes 18 years. Judging from the cause and development of sandstorms, man-made destruction of the environment and destruction of surface vegetation are the most important causes of sandstorms. Only by protecting vegetation and preventing land desertification can the harm of sandstorm be truly reduced.
The sandstorm disaster in China can be said to be more and more serious. According to expert statistics, from 1952 to 1993, the number of sandstorms in northwest China was: 5 in 195s, 8 in 196s, 13 in 197s and 14 in 198s; A violent black storm happened in 1993. After that, it happened at least once every April and May in Gansu Hexi Corridor, and in 2, it happened eight times in a row. According to authoritative experts' analysis, in 1-2 years, in the face of the increasing population and the worsening ecological environment, if effective measures are not taken, the frequency, intensity and harm of sandstorms in China may be further aggravated.
8. The worst sandstorm in the world
On May 12, 1934, the worst sandstorm occurred in the United States. The sandstorm originated in the western plains of the United States. A strong storm quickly swept across the vast land in the west, rolled up the fertile soil of thousands of hectares of farmland, and roared across the whole American land from west to east at a speed of 6-1 kilometers per hour. The sandstorm, which lasted for three days, scraped away an average of 5-13 cm of topsoil in the western United States, thus destroying more than 45 million mu of cultivated land, causing wells and streams in the western plain to dry up, crops to wither, and a large number of cattle and sheep to die.
historically, the north American continent is full of dense forests, abundant aquatic plants and abundant wildlife. With the western development of the United States, large areas of forests and grasslands have been destroyed. Americans almost cut down the endless forests from the Atlantic coast to the great plains, leaving the land bare, losing vegetation protection and planting a curse.
9. Minamata disease and painful disease
In 1953, a strange epidemic occurred in Minamata Town, Kumamoto Prefecture, Kyushu, Japan. First of all, a large number of sick cats appeared. These cats were crazy, staggered and bent, and committed suicide by jumping into the sea. Soon, a group of inexplicable patients appeared. At first, the patients were inarticulate and dull, and later developed into numbness and insanity, and finally died of screaming. It was many years before scientists found the cause of this strange disease: mercury poisoning. Originally, there was an acetic acid factory in Minamata town, which used mercury as a catalyst in the production process, and then discharged a large amount of mercury-containing wastewater into Minamata Bay. Mercury is very toxic. Under the action of microorganisms in water, it is transformed into methyl mercury with greater toxicity, which is enriched in fish, shellfish and so on. People eat these organisms polluted by methyl mercury before they get the terrible Minamata disease. Methyl mercury will gather in the human brain and damage the nervous system, so cats and people are crazy.
Painful diseases also occur in Japan. In Toyama Prefecture, Japan, local residents drink a river called Shentongchuan River and use it to irrigate crops on both sides. Later, Mitsui Metal Mining Company of Japan built a zinc smelting plant in the upper reaches of the river. The wastewater discharged from the zinc smelter contains a lot of cadmium, and the whole river is polluted by the cadmium-containing sewage from the zinc smelter. A lot of cadmium is enriched in river water, rice, fish and shrimp, and then it is enriched in the human body through the food chain, which makes the local people get a strange bone pain disease (also known as painful disease). Cadmium enters the human body, which causes a large amount of calcium loss in human bones, causing osteoporosis, bone atrophy and joint pain. There was once a patient who sneezed and broke many parts of his body. Another patient finally suffered 73 fractures in his whole body, and his body length was shortened by 3 cm. His illness was very miserable. Painful disease has been prevalent in the local area for more than 2 years, causing more than 2 deaths.
1. Noise pollution
Noise refers to sounds that people don't need. No matter what sounds are annoying and interfere with people's lives, they are all called noise. The roar of machinery in the factory, the horn of cars on the road and the noise of people are all headache noises. Sometimes strong rhythm of rock music, disco, etc. will also become noise, affecting people's life and health.
Strong noise can cause hearing organ damage, and the hearing of people who work in factories with roaring machines for a long time is often not as good as that of ordinary people. Noise can also seriously interfere with people's central nervous system, making people neurasthenia, indigestion, and even nausea and headache. Noise also has a great influence on people's normal life and work. It can make people lose sleep, lose appetite, and have troubles and other unpleasant emotions. Scientists have also found that long-term noise stimulation will also weaken the function of human immune system and increase the incidence of malignant tumors.
11. The concept of sustainable development
In the report "Our Future Together", the World Commission on Environment and Development made a clear definition of sustainable development: sustainable development is such a development that it not only meets the needs of contemporary people, but also does not harm the ability of future generations to meet their needs.
sustainable development is a comprehensive concept, and its rich connotation can be summarized into three points: ecological sustainable development, economic sustainable development and social sustainable development. The sustainable development of ecology, economy and society is interrelated and restricted, and * * * forms a composite system. Sustainable development requires people to live in harmony with nature and realize their responsibilities to nature, society and future generations. People are required to have high moral standards and protect the resources and environmental foundation necessary for human survival and development.
12. China's family background and sustainable development
In order to provide reference for high-level decision-making, China Academy of Sciences made the China Sustainable Development Report. The report shows for the first time the serious problems facing China. China's territorial environment is inherently fragile, which obviously exceeds the global average. 6% of the country is mountainous or hilly, 7% is affected by monsoon climate every year, and 55% is not suitable for human life and production; 35% often suffers from desertification caused by soil erosion, and 33% is in arid or desert areas. The per capita possession of water resources is 1/4 of the world's, and it is one of the 13 water-poor countries in the world. The human activities in China are obviously destructive, which is 3 to 3.54 times higher than the world average, and the number of earth and stone moving per person per year is 1.4 times that of the world average. Since the Sui Dynasty, the population of China has increased from about 46 million to 1.1 billion, and the average number of disasters per year has also increased from .6 to 3.9, an increase of 6.5 times. The development costs of China's 12 major industries, such as agriculture, animal husbandry and mining, are higher than those of the world. What the world has done with an average of US$ 1, China has to spend at least US$ 1.25.
the conclusion of the report is that China must go through three basic steps and achieve three basic goals in order to truly enter the threshold of sustainable development. Namely: zero growth in population scale in 23, zero growth in energy and resource consumption in 24 and zero growth in ecological environment degradation in 25.
People's livelihood
Sudan Red Duck Egg Event:
Almost all ducks on both sides of Yehe River in Pingshan County, Shijiazhuang City, Hebei Province laid "red heart" duck eggs. However, it was found that the so-called "red heart" duck eggs contained Sudan red in the feed additive. The reporter took some samples of "red medicine" and sent them to the Institute of Food Safety of China Academy of Inspection and Quarantine for testing. The results show that "Red Medicine" contains 46.5% industrial dye Sudan Red IV.
Sudan red, whose scientific name is Sudan, is divided into I, II, III and IV, all of which are industrial dyes. In the Sudan Red incident that sensationalized the whole country last year, 88 food samples, including 3 enterprises, were successively found to contain Sudan Red I.. Compared with Sudan I, Sudan IV is not only more brilliant in color, but also more toxic. The International Agency for Research on Cancer listed Sudan Red IV as a Class III carcinogen.
On November 12th, 26, CCTV Weekly Quality Weekly reported that individual markets and distribution enterprises in Beijing sold "red-heart duck eggs" produced by feeding ducks with feed added with Sudan red from Shijiazhuang, Hebei Province, and Sudan red was detected in this batch of duck eggs. The Ministry of Health issued a notice requesting all localities to urgently investigate and deal with "red heart duck eggs".