At the beginning of the new millennium, the themes of "World Water Day" and "China Water Week" are "Sanitary Water Use" and "Strengthening Conservation and Protection to Realize Sustainable Utilization of Water Resources" respectively. Looking at this theme, we can't help but think of the famous aphorism: If we don't cherish the precious water resources, then the last drop of water on the earth is probably our tears!
Water resources, a "crisis" facing human society.
Water is one of the important resources for human survival and development, and it is an indispensable and irreplaceable special resource. Without water, there would be no life, no civilization progress, no economic development and no social stability. The water resources in the world are limited, so the economic and social development must adapt to the water supply, and the water cannot be used indefinitely or exceed the carrying capacity of water resources. In today's world, with the continuous growth of population and economic development, the demand for fresh water resources is increasing day by day; At the same time, due to unreasonable utilization, the shortage of fresh water resources is increasingly tense.
China has been short of water for a long time. Historically, China is a country with frequent droughts, known as "nine droughts in ten years". In the historical documents of more than 2200 years, there have been 1300 droughts. China's per capita water resources are only about 2,300 cubic meters, which is about a quarter of the world's per capita water. Water resources in China are not only less per capita, but also unevenly distributed. The basin area north of the Yangtze River accounts for 63.5% of the land area, while water resources account for 19% of the whole country. With the development of society and economy, the gap of water resources is getting bigger and bigger. At present, China's agricultural irrigation lacks more than 30 billion cubic meters of water every year on average, and there are still more than 30 million people in rural areas who have difficulty drinking water. There are more than 400 cities in China that are short of water, and there are more than 1 10 cities that are seriously short of water. The daily water shortage in Chinese cities is160,000 cubic meters, which affects the industrial output value by more than 200 billion yuan every year, and the urban population is about 40 million.
In addition to China, there are many countries and regions in the world with serious water shortage problems.
The United Nations Water Conference pointed out: "We are entering a new era of water shortage". The increasingly serious global water crisis has aroused great concern of the international community. 1972 United Nations Conference on Human Environment and 1977 United Nations Water Conference warned the world: "Water will soon become a serious social crisis, and the next crisis after the oil crisis is water." Countries all over the world have begun to pay unprecedented attention to water problems, and gradually formed a * * * understanding of water crisis. 1In August, 1995, the World Bank survey report announced that 26 countries, accounting for 40% of the world's population, were facing water crisis, and their agriculture, industry and people's health were seriously threatened; About 654.38 billion people in developing countries do not have access to clean water, 654.38 billion people do not have good sanitation facilities, 80% of diseases are caused by drinking unclean water, and 25 million people die every year. 1999 World Water Day, the United Nations warned that with the development of human production and the improvement of living standards, the world water consumption is increasing at an annual rate of 5%, and the total water consumption will double every 15 years. Unless governments take effective measures, before 2025, more than half of the population on earth will face the crisis of fresh water resources, and more than one third of the population will not be clean. The shortage of water resources has become the main restricting factor of global social and economic development. Rational utilization of water resources is an urgent task for sustainable development of human beings, and water saving is the key to rational utilization of water resources, and it is also one of the fastest, most feasible and most extensive ways to maintain sustainable utilization of water resources.
Saving water is our common responsibility.
It can be said that through years of efforts, China has made great progress in water conservation, but compared with some developed countries, we still have a long way to go.
Agriculture is a big water user and a great waste of water resources. At present, the agricultural irrigation mode of "soil canal water conveyance plus flood irrigation" is still widely used in China. Half of the irrigation water is lost in the water conveyance, and the irrigation water utilization coefficient is mostly only 0.4, which is less than half of that of some developed countries. After irrigation with water per square meter, the grain yield in China increased by 0.5 kg, and that in developed countries could reach 2 kg. Industry, due to the backward technology of existing water facilities, the current water consumption per 10,000 yuan of industrial output value in China is 103 cubic meters, 8 cubic meters in the United States and only 6 cubic meters in Japan, which is 10 ~ 20 times that of developed countries; The reuse rate of industrial water in China is only about 40%, while the average level in developed countries is 75% ~ 85%. The phenomenon that urban residents don't talk about saving and waste domestic water is very serious, and water-saving education has a long way to go. Beijing alone leaks 360,000 tons of water every year. In Israel, which is also short of water, there are not only two sets of pipes for residents to flush toilets and wash their hands, but also two buttons for defecation. It was the Israelis with a strong sense of water crisis who invented the agricultural drip irrigation technology.
From now until the middle of the next century, China will fully realize the grand goal of socialist modernization. With population growth and socio-economic development, water consumption will increase substantially, and the contradiction between supply and demand of water resources will become more acute. It is predicted that the total water demand in 20 10 will be 698.8 billion cubic meters, in 2030 it will be 800 billion cubic meters, and in 2050 it will be at least 850 billion cubic meters, which will increase by 1995 respectively, so as to achieve a general balance between supply and demand of water resources in moderately dry years. It can be seen that the gap in water use is still quite large. Only by adhering to the principle of combining open source with throttling, putting throttling in the first place, further strengthening water conservation, realizing optimal allocation and efficient utilization of water resources centered on water conservation, and striving to achieve a basic balance between supply and demand, can the long-term economic development goal be successfully achieved.
Saving water and ensuring the sustainable utilization of water resources are our common cause and our common responsibility!
World fresh water resources
Many people imagine the earth as a blue planet, and 7 1% of its surface is covered with water. In fact, 97.5% of the water on the earth is salt water and only 2.5% is fresh water. Nearly 70% of fresh water is frozen in the ice sheets of Antarctica and Greenland, 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 on the mainland is about1100000000000000000000 cubic meters. After deducting the water absorbed by atmospheric evaporation and plants, the global river runoff is about 42700000000000 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.
Small water-saving method
Saving water is beneficial to the present and will make great contributions to the future. After discussion, the students came up with some ways to save water in life:
1. Washing vegetables with rice-washing water and then with clear water not only saves water, but also effectively removes pesticide residues on vegetables;
Second, wash the mop, sweep the floor, and then flush the toilet. The second washing water for washing clothes cleans doors and windows, furniture, shoes and socks, etc.
Third, flush the toilet after urinating, try not to open the big water pipe for flushing, and make full use of the used "dirty water";
4. Sprinkle water on the indoor and outdoor ground in summer to cool down, try not to use clear water, and use washing water after washing;
5. When cleaning bicycles and family cars, don't wash them with water, but wipe them with a wet cloth. If it is too dirty, wash it with the water left over from washing clothes.
6. Flushing the toilet: If you use water-saving equipment, you can save 4-5 kilograms of water each time;
Seven, family watering flowers, appropriate use Taomi water, tea, laundry water, etc. ;
Eight, household washing towels, small objects, fruits and other small amounts of water. It is advisable to use a basin to hold water instead of turning on the tap to flush;
9. Washing the floor: scrubbing with a mop can save more than 200 kilograms of water than washing each household with a faucet;
Ten, faucet used for a long time leaks. You can cut the rubber cover of the small penicillin bottle open to ensure no water leakage;
1 1. Adjust the floating ball in the toilet water tank down by 2 cm, saving nearly 3 kg of water each time; If you use it four times a day at home, you can save 4380kg of medicine a year.
Twelve, washing vegetables: a pot of a pot, do not run the faucet, a meal can save 50kg；;
13. Shower: If you turn off the tap to wipe soap, you can save 60kg of water by taking a shower;
14. Hand-washing clothes: If you use the washbasin to wash clothes, you will save 200kg of water each time compared with turning on the tap;
15. Washing clothes with a washing machine: I suggest you fill a bucket before washing. If washed twice separately, it will consume120kg; More water.
Water saving slogan
1, saving water is an important measure to implement the sustainable development strategy.
2. Strive to create a water-saving city and implement sustainable development.
3. Vigorously popularize water-saving domestic water appliances.
Saving water and protecting water resources is the common responsibility of the whole society.
5. Pay equal attention to open source and throttling, give priority to throttling, give priority to pollution control, open source scientifically and comprehensively utilize.
6, the state plans to use water, strictly save water.
7. Cherish water, cherish water and save water, starting from me.
8, insist on saving water in the first place, and strive to build a water-saving city.
9, save water, benefit mankind, benefit in the contemporary, work in the future.
10, control water according to law, use water scientifically and save water consciously.
1 1. Strengthen urban water-saving management and save and protect urban water resources.
12, and strive to establish a water-saving economy and water-saving society.
13, protecting water resources and promoting the development of the western region; Save every drop of water and create a water-saving city.
14, saving water is the responsibility and obligation of every citizen.
15. Water is the source of life, the blood of industry and the lifeblood of cities.
16, cherishing water means cherishing life.
17, please cherish every drop.
18, Water shortage in the world, China and cities, please save water.
19, it is shameful to waste water and glorious to save water.
20. Water is an irreplaceable precious resource.
2 1, save water, pay attention to rational water use, and use water scientifically.
22. Establish a good fashion that everyone cherishes and everyone saves water.