The earth's water reserves are very rich, * * * as much as145 billion cubic kilometers. Although there is a huge amount of water on the earth, it is pitiful that it can be directly used for production and life. First of all, seawater is salty and bitter, so it can't be drunk, irrigated or used for industry. Secondly, the earth's fresh water resources only account for 2.5% of its total water, and more than 70% of these rare fresh water resources are frozen in the Antarctic and Arctic ice sheets, and 87% of the fresh water resources are difficult to use, plus the hard-to-use alpine glaciers and permafrost snow. The fresh water resources that human beings can really use are part of rivers, lakes and groundwater, accounting for about 0.26% of the total water of the earth. The global freshwater resources are not only in short supply, but also the regional distribution is extremely unbalanced. In terms of regional distribution, the freshwater resources of Brazil, Russian Federation, Canada, China, USA, Indonesia, India, Colombia and Congo account for 60% of the world's freshwater resources. About 654.38+0.5 billion people in 80 countries and regions, which account for 40% of the world's total population, are short of water, of which about 300 million people in 26 countries are extremely short of water. Even more frightening is that by 2025, 3 billion people in the world will face water shortage, and 40 countries and regions will be seriously short of water.
[Edit this paragraph] Present situation of water resources in China
The total water resources in China is 2.8 trillion cubic meters. Among them, 2.7 trillion cubic meters of surface water and 0.83 trillion cubic meters of groundwater. Because surface water and groundwater are mutually transformed and replenished, after deducting the amount of repeated calculation, the amount of groundwater resources that are not repeated with river runoff is about 0. 1 trillion cubic meters. According to internationally recognized standards, the per capita water resources below 3000 cubic meters are mild water shortage; The per capita water resources below 2000 cubic meters are moderately short of water; The per capita water resource 1000 cubic meter is a serious water shortage; Water resources below 500 cubic meters per capita are extremely short of water. At present, the per capita water resources of 16 provinces (autonomous regions and municipalities) are below the critical water shortage line, and the per capita water resources of 6 provinces (autonomous regions and municipalities) are below 500 cubic meters (Ningxia, Hebei, Shandong, Henan, Shanxi and Jiangsu). The total amount of water resources in China is not too large, ranking sixth in the world, but the per capita possession is even less, with 2240 cubic meters, ranking 88th among 153 countries counted by the World Bank. The regional distribution of water resources in China is also very uneven. The Yangtze River basin and its south area only account for 36.5% of the country's land area, and water resources account for 8 1% of the country. The area in the north accounts for 63.5% of the whole country, and the water resources only account for 19% of the whole country.
[Edit this paragraph] How to save water resources
What should we do in the face of this severe water resources situation:
1, you should have the consciousness of cherishing water. Only when you realize that "saving water is glorious and wasting water is shameful" can you pay attention to saving water all the time. Start with the little things around you,
2. Develop good habits, such as turning off the dripping faucet.
3. Use water-saving appliances,
4. Leakage and blockage. As far as production is concerned, especially for some industries with high water consumption, we should actively organize technical research to improve the comprehensive utilization rate of water around how to optimize the operation of water system, how to improve the concentration multiple of circulating water and how to improve the recycling utilization of water resources; At the same time, a feasible operation system is formulated to manage the water consumption of products in quota, which is used as a technical and economic index for assessment to reduce waste.
Many people imagine the earth as a blue planet with 7 1% surface covered by water. In fact, 97.5% of the water on the earth is salt water and only 2.5% is fresh water. In fresh water, nearly 70% is frozen in the ice sheet of Antarctic and Greenland water pollution data, and most of the rest is soil moisture or deep groundwater, which is difficult to exploit for human use. Water from rivers, lakes, reservoirs and shallow groundwater is easy to be exploited for human direct use, but its amount is less than 1% of the world's fresh water, accounting for about 0.007% of all water on the earth. The annual precipitation of water data falling on the mainland in the world is about 1 10 trillion cubic meters. Excluding atmospheric evaporation and water absorbed by plants, the global river runoff is about 42.7 trillion cubic meters. According to the world population 1995, the per capita annual water consumption is 7300 cubic meters. Due to the increasing world population, this average is 37% lower than that of 1970.
[Edit this paragraph] The water pollution problem in China.
If you don't cherish it, the last drop of water is equivalent to blood (the cry of nature's grief and indignation)
Seven major water systems, namely Haihe River, Liaohe River, Huaihe River, Yellow River, Songhua River, Yangtze River and Pearl River, are all polluted to varying degrees.
The situation along the coast of Wan Li is also not optimistic, with red tides coming as scheduled every year. In the beautiful Bohai Bay, turbid water splashes, and the oil floating on the sea burns life in the ocean like a black torch.
With the gradual development of science and the gradual increase of high-rise buildings, the problem of water shortage is becoming more and more serious. With the destruction of mankind, the original blue "crystal ball" is no longer Ming Che, no longer blue, and will soon dry up.
Although 7 1% of the earth's surface is covered with water, in fact, fresh water resources only account for about 2% of the earth's total water, and the total amount of fresh water available to human beings only accounts for three tenths of the earth's total water, accounting for 0. 34%。 It can be seen that there is not as much water available on the earth as humans think. If it is allowed to continue to be destroyed by human beings, it will disappear sooner or later.
First of all, we should establish the consciousness of cherishing water and carry out water resources warning education. For a long time, most people generally believe that water is an inexhaustible "cornucopia", which is wasted in use and does not know how to cherish it consciously. In fact, the water resources on the earth are not inexhaustible. Especially in China, the per capita water resources are not rich, the regional distribution is uneven, and the year is unpredictable, with great inter-annual differences. Coupled with serious pollution, water resources are even more scarce, which is vividly reflected in the repeated water cuts of the Yellow River. National water resources utilization projects such as "Yellow River Diversion Project" and "South-to-North Water Transfer Project" are aimed at solving the water shortage problem in some areas, but we should think deeply: Where can we "divert water from the Yellow River" when the water in the Yellow River is exhausted? The water in the south is polluted. How to "transfer water to the north"? Therefore, people must establish the consciousness of water crisis, take saving water resources as our conscious code of conduct, and carry out water resources warning education in various forms.
Secondly, we must develop water resources rationally to avoid the destruction of water resources. Water resources development includes surface water resources development and groundwater resources development. When exploiting groundwater, because the water quality between aquifers is very different, it should be exploited in layers. Contaminated diving and confined water shall not be mixed; For exploration projects that expose and penetrate the water layer, layered water sealing and hole sealing must be carried out in strict accordance with relevant regulations to effectively prevent water pollution and ensure the sustainable development of water bodies.
Modern water conservancy projects such as flood control, power generation, shipping, irrigation, aquaculture water supply, etc., while exerting one or more economic benefits, will also have a certain negative impact on the natural and social environment of the project location, upstream and downstream, estuaries and even the whole basin, and may also cause water resources destruction in a certain range. In addition, the destruction of water resources by some mining industries can not be ignored. For example, coal mining discharges 0.88 cubic meters of water for every ton of coal mined. According to the annual coal mining of 300 million tons in our province, the loss of groundwater resources is as high as 250 million cubic meters, which has caused great damage to the geological structure of groundwater. For another example, unrestricted deforestation will cause serious damage to vegetation, and it will also have a certain impact on soil and water conservation and surface burial of water resources.
Third, improve the utilization rate of water resources and reduce water waste. The key to effective water saving is to reuse water resources by using "reclaimed water". In addition, the effective utilization of water resources is regulated by economic leverage. Because water control is not in place, many places have flowing water, and some places will "hold bowls and pray". Therefore, it is necessary to install an effective water metering device and implement the principle of using more water and charging more, so as to achieve the purpose of saving water. Urban water quota management is an internationally accepted method. On the premise of scientific verification of water consumption, adhere to the principle of classified treatment. Different water prices shall be imposed on citizens' domestic water, industrial and commercial enterprises' water and government institutions' water, and the excess shall be appropriately raised to cultivate citizens' habit of saving water.
While saving water resources, we should avoid ineffective waste. In winter in the north, water pipes are prone to frost crack and serious water leakage, so special attention should be paid to prevention and inspection; With the development of social economy and the acceleration of urbanization, in order to alleviate the shortage of water resources, in addition to vigorously saving and protecting water resources, inter-basin water transfer has become an inevitable choice for cities in northern China, which will inevitably bring about changes in the relationship between supply and demand of water resources, so water rights trading must be implemented; Since China implemented the "welfare water" system, water has not been treated as an economic commodity. Therefore, in the preparation of water resources, the market mechanism is usually replaced by the control method. At present, we should change our ideas, recognize the natural and commodity attributes of water resources, follow the laws of nature and value, truly treat water as a commodity, rationally allocate water resources by using market mechanisms, and reduce resource waste.
Fourth, carry out water pollution prevention and control to realize comprehensive utilization of water resources. Water pollution includes surface water pollution and groundwater pollution. Industrial wastewater, industrial garbage, industrial waste gas, domestic sewage and domestic garbage produced in the production process can all cause water pollution through different infiltration methods. For a long time, environmental incidents caused by direct discharge of industrial production sewage are common, which have brought extremely bad effects on human production and life. Therefore, effective prevention and control of production and domestic sewage should be carried out. Cities can adopt centralized sewage treatment; Industrial enterprises must implement the "three simultaneities" system of environmental protection; According to the different properties of production sewage, corresponding sewage treatment measures are taken. In short, we must resolutely implement the supervision and management system for water pollution prevention and control, adhere to the principle that whoever pollutes will control it, strictly implement the one-vote veto system for environmental protection, promote the sewage treatment work of enterprises, and finally realize the comprehensive utilization of water resources.
Water is the material basis for the existence of life on earth, and water resources are the primary condition for maintaining the sustainable development of the earth's ecological environment. Therefore, protecting water resources is the greatest and most sacred duty of mankind.
According to statistics, more than 400 of the 660 cities in China are short of water, of which two thirds are short of water. The annual water shortage of cities in China is about 6 billion cubic meters, among which the cities with serious water shortage are 1 10. A large number of fresh water resources are concentrated in the south, and the fresh water resources in the north are only 1/4 in the south. In addition to water shortage, water pollution is also a prominent problem. According to the 200 1 monitoring of the sections of seven major water systems in China, only 29% of the sections meet the minimum requirements for the three types of water quality to enter the waterworks. 5%, while the water quality of the inferior five categories is as high as 44%; In addition, the pollution of shallow groundwater resources is more common in China. About 50% of the shallow groundwater in China is polluted to varying degrees, and about half of the urban areas are seriously polluted. Due to the wanton discharge of industrial wastewater, more than 80% of surface water and groundwater are polluted. At present, China's urban water supply is mainly surface water or groundwater, or a mixture of the two sources. However, the long-term over-exploitation of groundwater in some areas of China leads to the decline of regional groundwater level, and finally forms a funnel of regional groundwater level decline. At present, more than 100 regional groundwater drop funnels have been formed in China, covering an area of150,000 square kilometers, and some cities have formed large funnels with hundreds of square kilometers, making seawater flow backwards for dozens of kilometers.
1, vigorously develop greening, increase forest area and conserve water. Forests can conserve water, reduce ineffective evaporation, regulate microclimate, and have throttling significance. It can increase the precipitation in forest areas and forest edges, which is of open source significance.
2, improve the comprehensive utilization rate of water resources, water has the characteristics of comprehensive utilization in the same space. Reservoirs can store floods and cultivate aquatic animals and plants. The large water surface is navigable and some water bodies can also be used for tourism. The water used for hydroelectric power generation can be used for irrigation. The water leaked from canals and fields can be pumped underground, and the water pumped underground can also be pumped downstream of irrigation areas for reuse. Xinjiang is an arid area. Without irrigation, there would be no agriculture. Trying to improve the water diversion rate of rivers and arrange the relationship between upstream and downstream water use is equivalent to opening up water sources.
3. Water transfer project. Due to geographical and climatic characteristics, the distribution of water in different regions is unbalanced. Using natural factors and artificial transformation to transfer water from water-rich areas to water-deficient areas is an effective means to solve the water shortage problem and open up new economic zones.
4. Protect water resources. Water resources are polluted, which makes the available water unusable, which is actually equivalent to reducing water resources. At present, 40% of the rivers in the world are polluted to varying degrees, and there is an upward trend.
5, the development and utilization of urban sewage resources, the development of water treatment, sewage reuse technology. After treatment and purification, the high-quality miscellaneous drainage produced by some industrial production and life in the city can reach a certain water quality standard and can be used as non-drinking water for greening and sanitation.
6. Develop and popularize water-saving appliances. According to incomplete statistics, there are nearly 40 million sets of toilet water tanks and a large number of other sanitary appliances in China, and the water lost every year due to the leakage of toilet water tanks reaches hundreds of millions of cubic meters.
7. Strengthen the legal construction and publicity work of protecting water resources and saving water, enhance the awareness of saving water for the whole people, make people consciously realize that water is a valuable resource, abandon the outdated concept of "inexhaustible", and a good social fashion of cherishing, saving and protecting water resources has taken shape.
To protect water resources, we must first mobilize the whole society and change the traditional concept of water use. To make everyone realize the preciousness of water, the water used to flush toilets is equivalent to the per capita daily water consumption of some developing countries; Taking a cold bath in summer is equivalent to the daily water consumption of dozens of people in water-deficient countries; If the faucet is not tightened, the water lost in one night is equivalent to the total amount of drinking water in a village in Africa or Asia. This is by no means sensational, but the result of years of investigation by relevant United Nations agencies. Therefore, it is necessary to call on the whole society to save water, use more water and make full use of circulating water.
Reforming the current water use system, strengthening government macro-control and strengthening pollution control and environmental protection are effective ways to protect and utilize water resources. At present, we should intensify the reform, break the monopoly of the industry, improve the organization and unified management, and establish a bottom-up water supervision system nationwide. Further reform the water price, implement seasonal water price, levy higher consumption tax in water-deficient areas, and limit water use. Only in this way can it be beneficial to environmental protection, reduce costs and take the road of sustainable development.
It is also an important content of protecting and utilizing water resources to make full use of market mechanism and develop water market with China characteristics, so as to optimize the allocation of water resources. 2 1 century is called the century of water. China's water industry has ushered in an unprecedented development opportunity. It is predicted that the aquaculture industry in China should have a space of more than one trillion yuan, and by 2005, the market share of sewage treatment alone will be 400 billion yuan. Over the years, because "water" has a strong social welfare color, it is not a real commodity. The deviation between the value and price of water seriously restricts the development of aquaculture, and water resources cannot be effectively protected. This situation should be changed in the new historical situation.
China is a country with severe drought and water shortage. The total amount of fresh water resources is 2.8 trillion cubic meters, accounting for 6% of the global water resources, ranking fourth in the world, second only to Brazil, Russia and Canada, but the per capita is only 2,200 cubic meters, which is only 1/4 of the world average, and 1/5 of the United States, ranking 1 2 1 in the world.
According to the monitoring, the groundwater in most cities in China is polluted to a certain extent, and it is getting worse year by year. The increasingly serious water pollution not only reduces the use function of water, but also intensifies the contradiction of water shortage, which seriously affects the sustainable development strategy being implemented in China, and also seriously threatens the drinking water safety of urban residents and the health of the people.
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