Title: Present situation of human water resources

Water is the basic condition for the reproduction and survival of human beings and other creatures, an irreplaceable important resource for people's lives, the most active and influential factor in the ecological environment, and an important resource for industrial and agricultural production, with unique performance and multiple use functions that many other resources do not have. In industrial production, water has a series of functions such as cooling, processing, boiling, power generation and transportation. Agricultural water accounts for 73% of global water consumption, mainly referring to irrigation water.

China is short of water resources, and the per capita water resources only account for 1/4 of the world average. Although the total amount of water resources in China is about 2.8 trillion cubic meters, the regional distribution is very uneven, with 80% distributed in the south, while the cultivated land in the south only accounts for about 1/3 of the total cultivated land area in China. The water and soil resources are not matched, and the ecological environment is relatively fragile. China is a vast country with a huge span from north to south. It is difficult to transfer water for a long distance, so the total amount of water resources available is not very large. China has a per capita water resource of 2,300 cubic meters, the peak population will reach 65.438+0.6 billion in 2030, and the per capita water resource will be 654.38+0.700 cubic meters, which will be close to or reach the world-recognized warning line for water use. The shortage of water resources will increasingly become a serious constraint to the economic and social development of China. The average annual cultivated land area affected by drought in China is about 400 million mu.

As a result of the imbalance between supply and demand, firstly, the national economy water squeezes the ecological environment water, and secondly, the urban and industrial water squeezes the agricultural water. At present, the water resources development plan in North China has exceeded 50%, which has caused rivers to cut off and lakes to shrink. Excessive discharge of sewage in the southern water network area causes water pollution; A large amount of ecological water is squeezed out in the arid area of northwest China, and the trend of desertification is spreading; The water content of steep slopes in southwest hilly areas is low, and the project of water resources development and utilization is arduous. From a national perspective, the carrying capacity of water resources and the capacity of ecological environment are obviously insufficient.