Source of information: China Water Network
most of the world countries due to inadequate water management, thus losing valuable human resources - water conservation. This fact from the increasingly tense world situation and the increasingly frequent water ecological health of water seen in the alarm. In some areas, water was precious than oil, yet still in the continually being wasted. can be said that water is the most scarce natural resources. 1. ensure that water supply development is inseparable from the human
plenty of water. In fact, for centuries, the water in the promotion of social development, agricultural expansion and traffic transport plays an important role. Therefore, water in human activities at the center. It is also a lot of projects, activities and investment focus, such as the construction of dams, canals, water pipelines and irrigation systems and so on. Today, the world has more than 45,000 dams (dam height of 15 meters or more) , most of these dams built in the last 35 years. This shows that the human since 1950 on the river system over the past investment in water storage capacity of 700%. <> river water storage capacity increases so that people through irrigation to expand their agriculture, and enable the distribution of water uniformly distributed within a year, which solves many of the seasonal water shortage problems. <>, but the increase in water demand quickly, so we can be collected, stored and used water supply is threatened. From 1900 to 1995, global water consumption increased by 6 times higher than the rate of population growth is also twice as fast, and, as agricultural, industrial and residential water demand increase in water demand will be for the global increase. <> environmental impact and to our water consumption was increasing. For example, the increase in the number of rivers to dam the river is divided into many of our river, the river Runoff characteristics also change. According to statistics, more than 60% of the world are the runoff characteristics of the river basin as a dam and major changes have taken place. The split in the river basin carries 90% of the runoff. With the growth of population and changes in freshwater systems, many of the basic function of watershed have been affected and more difficult to ensure that there is enough water for human and natural use. <> 2. how the shortage of water? <> humans each year need to reference the source of about 4 trillion cubic meters, about the Earth's total river runoff of 20% (average dry weather flow). This figure needs to understand that people understand the background of the global water cycle: Scientists estimate that the average global runoff ( After the rain evaporation and infiltration beyond that amount of water used for human) is about 45,0000-45,0000 billion cubic meters a year between, however, not all of these are human beings can use water, which is mostly As a result the flood event, or location of the runoff leaving humans can not be far away. <> In addition, part of the runoff also need to remain in the river system to make the river ecosystem to continue to function. In fact, every year human beings really can get the total runoff of about 9 trillion cubic meters, about 3.5 trillion cubic meters is stored in reservoirs and lakes. <> Still, this is not a complete description of the world's average water the earth, the global The water supply is unbalanced, there is sufficient water in some areas, some local water supply is very limited. For example, the arid and semi-arid regions runoff only 2% of the world, even though these regions account for 40% of the area of the world. In some basins, water demand higher than the number of available runoff, water shortages will become more of a problem. <> World Resources research institutions and the United Kingdom University of New Hampshire's water shortage on the world carried out Estimation results show that: living in the basin in the world, 41% of the population, or that 20-30 million people face water shortage problem. This means that these people's water supply per person per year less than 1,700 cubic meters . many of these areas, the water supply is actually less than the annual average of 1,000 cubic meters. in some watershed areas of high tension of water resources, water shortages caused by the serious consequences of lack of local food production and economic development is slow. while the rich areas, people have enough money and capacity for water use, protection and re-use of technological innovation, the result is increased regional disparity. According to statistics, Approximately 17 million people (which is raised to 20-30 million people over a part of) the shortage of water in a high state. <> If the current water consumption patterns do not change, by 2025, living in the basin in the world a population of around 3.5 billion, or 48% of the global population will face water shortages are the problem. even in some years it seems more adequate water supply areas to the year when the average amount of water each month, will also be relatively dry seasonal water shortages occur. <> The results show that the increase in water consumption as the world, in another quarter of a century, the world is very famous in many river basins slowly into the state of water shortage (per capita water supply less than 1,700 cubic meters). <> 3. waste of water resources: inefficiency, overuse and pollution of <> the world's population growth inevitably require more food production, the United Nations estimated that by 2025 World population will reach at least 80 million, than it is now increased by 17 billion. This means that farmers need more water to irrigate. Over the past 50 years, the fact that the increase in food production and water to increase the model is basically the same, For example: From 1950 to 1995, food increased by 2.4 times, while irrigation water use has increased 2.2 times. At present, irrigated agriculture accounts for 40% of world food industry, despite the world's irrigated agriculture accounts for only 17% of arable land. The results show that agriculture is the main water user community, the water consumption accounts for about 70% of all water. <> However, unfortunately, is: most of the irrigation systems are relatively inefficient, there are a lot of water waste . world-wide assessments indicate that about 60% of the irrigation water did not reach crops, but lost by evaporation or infiltration out. <> In addition to the backwardness of agriculture than irrigation technology, in fact, the farmers for their irrigation water The cost is very low, so they no incentive to conserve and protect water resources. Government water resources for agriculture to help farmers of subsidies also do not know the treasure of valuable water resources. In the U.S., the annual agricultural water resources funding to reach 20-25 million U.S. dollars. <> from a global perspective, government relief acts contributed to some of the water body tissue cheap sell irrigation water, causing huge losses. In arid Tunisia, farmers only pay for irrigation water supply costs The seventeenth of the water, so low prices and high government subsidies led to inefficient use of irrigation water, and not conducive to the promotion of water-saving irrigation, such as using drip irrigation techniques. <> water pollution to Local or regional water shortage is more serious, much less be reflected in the water supply. In many parts of the world, lakes and rivers is very serious pollution, water quality can not meet even industrial use. <> 4 .
groundwater is also a shortage of water shortages worldwide, including not only the surface water, including groundwater. Asia has more than 10 million people, and the Americas about 1.5 billion people rely on groundwater wells or springs of life. In addition, the rural use of groundwater The situation is still no exact statistics, many urban residents rely on groundwater and the extent of agricultural water are increasing. At present, the human extraction of about 6000-7000 million cubic meters per year of groundwater, accounting for about available groundwater for 20% of the total. <> from the shallow aquifer, and is part of Earth's water cycle, can always be supplemented and updated. <> In fact, the excessive exploitation of groundwater can also be connected to it significantly reduced the water level in the river or lake. Similarly, contaminated groundwater, such as nitrates, pesticides and industrial chemicals are often violations of water adjacent freshwater ecosystems. Although, over-exploitation and serious pollution of the groundwater has become a major issue worldwide, but the world the amount of resources and pollution of groundwater in the absence of the trend of the exact statistics. <> 5. scientific management means more water <> science is to ease future water resource management to avoid future water shortages and water The key ecological damage. In the short term, more effective use of water can greatly expand the availability of water level. <> This assertion is especially true for agriculture, experience shows that the drip irrigation system can save typically 30-70% of irrigation water, while irrigated crop production increased 20-90%. Nevertheless, in the past 20 years, the global use of drip irrigation in the region increased by 50 times more, but this area of the Earth accounts for only 1% of arable land . <> efficient water technology alone can not solve the water crisis in the future. In order to make water resources can be more economic and effective use, it is necessary redistribution of water resources. This means that it is possible to water from agriculture or industrial or commercial in the recall, and for living. For example, in China, it is estimated that the same economic benefits of water for industrial agriculture for more than 70 times.
sense, human the use of water transfers from low value to higher value use of the practice has already begun, particularly those able to use their hands in the water right transfer people to other independent entities. outskirts of Tirupur in southern India, farmers are doing: they abandoned agricultural land out of cultivation and sale of out, so land is just some of the groundwater in the water industry or user needs, and they changing this through the use of groundwater and get extra income. The operation of the market mechanism in the water Western Australia is becoming increasingly common. <> water resources allocation and use of more effective is an important key: the need to lift some of the supplementary protection of water resources, so that water can be a true reflection of water supply the real cost. <> Chile reduced irrigation water price reform of water 22-26%, and savings of 4 billion U.S. dollars, the money can be used for new water supply infrastructure. in Indonesia Bogor, water reduce the price of water for living up to 30%. However, the effective water prices, especially the price of irrigation water is still concerned about the low-income countries, because agriculture is still the economic support of these countries, most of the income of farmers is limited. <> 6. Inspiration <> China is the world's one of 13 water-poor countries, the total fresh water resources, although the sixth highest in the world, but the world average per capita is only 1 / 4 No. 121 in the world. 669 cities nationwide, there are 400 cities lack water supply, water shortages amounted to 6 billion tons. life in rural areas and agriculture is also a serious water shortage, the current 4,300 million rural residents have drinking water, crop water shortage average annual area of 4 million hectares of drought, water shortages 300 billion cubic meters. Some experts predict that by 2030, China's per capita water resources will be reduced to 1760 cubic meters of water will be about 40 billion to 50 billion cubic meters, and may cause serious ecological problems. <> water resources management from abroad, we should: <> using scientific means to water resources management - a scientific means more water resources management, efficient water use to improve water access program. National Water Resources Management for a special committee to coordinate water and protect water resources of the department activities; organize relevant departments to actively study the water-saving technologies and equipment to promote the scientific management of water resources. <> ; vigorously promoting conservation of agricultural water irrigation - irrigation in China is the world's largest country, but China has a serious waste of irrigation problems: low efficiency, it should take effective water-saving sprinkler and drip irrigation methods. <> ; industrial water to adjust the structure of water - industrial water recycling rate of only 30%, far lower than developed countries 75% -85% level, In addition, studies have shown that part of the agricultural water into the practice of industrial water is good . So to learn the advanced experience of foreign countries, adjusting the structure of water, water efficiency, the industrial water recycling rate to a new level. <>, where necessary, a fixed water distribution areas - large areas of water resources particularly tense, no matter agriculture, industry, water consumption, water distribution system should be a fixed, the implementation of the water to the unit and individual indicators in order to achieve the purpose of water conservation. while also the use of price leverage, fixed charge at par within the water, over high water collection, waste water should be punished, in order to cultivate the habit of people to save water. <> use legal means to stop serious water pollution - water resources department, according to monitoring more than 1,200 rivers in the country, more than 850 contaminated, so a lot of water Resources was forced to retire. Meanwhile, my serious soil erosion, loss of topsoil each year about 50 million tons, so a lot of pesticides and fertilizers with topsoil into the rivers. so to take the law as a means of severe penalties, to stop the occurrence of pollution.
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