When will the Earth s water resources be used up?

At present, the earth still has abundant water resources, but there are still problems such as water shortage, water pollution and spring dyeing. According to a 2006 report by the United Nations Environment Programme in South Africa, only one of the world's total amounts of freshwater is available globally, and most of it is stored in snow and ice in the Antarctica and Greenland ice sheets, which are not fully utilized and very costly.

Nearly 40% of the world's population lives in areas where water or access to water is scarce, and water scarcity is likely to be exacerbated in some areas due to climate change and other factors. Water pollution is also one of the serious problems we are currently facing, and it is difficult for traditional water treatment methods to effectively deal with complex pollutants, so it is necessary to find new technical means and management methods to ensure people's drinking water safety and environmental health.

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Analysis: At present, the freshwater resources that are relatively easy for human beings to use are mainly river water, freshwater lake water, and shallow groundwater, and the reserves account for about the total freshwater reserves in the world, accounting for only 7/100,000 of the total water reserves in the world. According to research, from the perspective of the water cycle, about 9,000 kilometres of freshwater resources are actually used efficiently in the world per year3.

Water resources. The Earth's water resources, broadly speaking, refer to the total amount of water in the hydrosphere.

Seawater is brackish water and cannot be used directly, so the water resources commonly referred to mainly refer to freshwater resources on land, such as river water, freshwater lake water, groundwater and glaciers. Freshwater resources on land account for only the total amount of water on the planet, and most of them (nearly 70) are pure laughing glaciers, that is, alpine glaciers distributed in the polar regions and in the middle and low latitudes, which are still difficult to use. At present, the freshwater resources that are relatively easy for human beings to use are mainly river water, freshwater lake water, and shallow groundwater, and the reserves account for about 7/100,000 of the world's total freshwater reserves.

According to research, the world's freshwater resources are actually used effectively at about 9,000 kilometres per year3 from the perspective of the water cycle.

Generally speaking, areas with abundant precipitation have abundant water resources; Areas with low precipitation are poor in water resources. It reflects the abundance of water resources in a country or region, and usually refers to the total amount of annual average runoff and per capita occupancy. Total river runoff worldwide is 47,000 km3, with a per capita average of about 9,000 m3.

The total amount of river runoff in China is about 2,700 billion m3, and the average per capita share is about 2,400 m3, which is much lower than the per capita share of the world.

First of all, the earth has its own water cycle, and the overall water resources will not change much, and we need to consider the safe fresh water that can be used by humans.

Although 70 percent of the Earth is covered with water, only 2.5 percent of it is freshwater for human use. Currently, 1.1 billion people lack access to safe drinking water, and 2.4 billion people lack adequate water and sanitation. The United Nations warns that by 2025, nearly half of the world's population will live in water-scarce areas.

Areas of water scarcity or water stress are expanding, particularly in North Africa and Western Asia. According to the World Summit on Sustainable Development, agriculture accounts for about 70 percent of the world's freshwater resources, and the United Nations predicts that in the next 20 years, the world will need 17 more freshwater to irrigate crops to meet human food consumption, plus industrial, domestic and municipal water supplies, and the overall freshwater supply will need to increase by 40 percent by 2025The water crisis has seriously constrained the sustainable development of mankind.

The irrational use of human resources has also led to the shrinkage of water resources. The destruction of freshwater systems in lakes, rivers, wetlands and underground aquifers due to excessive water use, water pollution and the introduction of invasive alien species has had serious consequences for humankind. In some parts of the United States, India, and China, over-exploitation of groundwater and the inability of the waterbed to replenish the water supply of rivers have often caused rivers to break off and dry up downstream, such as the Colorado River in the United States and the Yellow River in China.

The energy issue is the essence.

Fresh water is not a problem after solving the energy problem.

The earth's water resources will not be used up, but will only be polluted;

After water resources are used, they return to nature through water vapor and polluted water, and through the circulation of water, water resources will purify themselves to remove pollutants, and form water vapor and precipitation again to replenish groundwater, so water resources will not be used up, but will only be polluted;

Although the amount of water on the earth is huge, there is very little water that can be directly used by people in production and life. First of all, seawater is salty and bitter, undrinkable, unwaterable, and difficult to use for industry. Second, the earth's freshwater resources account for only a fraction of its total water, and of these very few freshwater resources, more than 70% are frozen in the Antarctic and Arctic ice caps, and together with the inaccessible mountain glaciers and permafrost snow, 87% of the freshwater resources are difficult to use.

The freshwater resources that humans can really use are some of the rivers, lakes and groundwater, which account for about the total amount of water on the planet.

It depends on the rate at which humans are destroying the natural environment. But in general, if we don't strengthen management and control now, we will be at mostYear 1500After that, there is no water available.

In the natural condition of the earth's self-regulation, fresh water will never disappear, but the negative effect of human development will destroy the ability of nature to regulate, soon, the known water sources will be polluted in two or three hundred years, like rain, snowfall will fall acid rain, the earth will lose its self-regulation ability, people will go to the north and south poles to develop fresh water, which will supply human beings with fresh water for about a thousand years.

The important role of water resources

Regulate the climate. Water mills shape the Earth's surface.

Water has the function of transporting substances.

Water is an indispensable substance for all living things.

Water is the most basic material basis for human survival and production.

World Water Profile:Natural conditions vary greatly from precipitation to runoff around the world.

The islands of Oceania (excluding Australia) receive the highest annual precipitation; This is followed by South America, where most of the region is located in the equatorial climate zone, where the water cycle is very active, with precipitation and runoff more than twice the global average. Europe, Asia and North America are close to the world average, while the African continent is one of the driest regions in the world, with precipitation close to the world average, but due to the large desert area and strong evaporation, the runoff is only 151 mm. In contrast, Australia in Oceania is the driest, with a runoff of only 39mm compared to 761 mm of precipitation, which is due to the fact that 2 3 of Australia's areas are deserts and semi-deserts.

Characteristics of China's water resources:The total amount of water resources is relatively abundant, and the per capita and per capita land holdings are small.

China's annual average annual water resources are 2,812.4 billion m. Among them, river runoff accounts for about 94%, which is lower than Brazil, the former Soviet Union, Canada, the United States and Indonesia, and accounts for about the total global runoff, ranking sixth in the world.

The average runoff depth is 284 mm, which is 90% of the world average, ranking 7th in the world. It can be seen that China's water resources are still relatively abundant.

China has a large population, calculated according to a population of 1.2 billion, the average annual river runoff per person is 2260m, which is less than 1 4 of the world average, which is 1 6 per capita in the United States, 1 8 in the former Soviet Union, 1 19 in Brazil and 1 58 in Canada.

China has a vast territory, and the average river runoff per hectare of cultivated land is about 28,320m, which is 80% of the world average.

Therefore, the contradiction between the amount of water resources and the needs of our country is very prominent, and 22% of the world's population is supported by 7% of the world's arable land and 6% of the world's freshwater resources.

Solution:

Improve the efficiency of water use and open up a second source of water.

Regulate the flow of water sources to increase reliable water supply

1. According to the global surface in 2015.

Incoming water will be exhausted (China since.

Science and technology information) reported Bai Dao, the United States.

The University of Budford Business School and the DAO of the Centre for Science and Environment in Delhi, India, released several alarming research reports on World Water Day (22 March). These studies report that the Earth's water resources are rapidly declining, and that global surface water may be depleted by around 2015. By then, nearly half of the world's population, especially the world's two most populous countries, China and India, will likely face shortages of basic drinking water**.

2. The freshwater resources on the earth only account for about 2% of the total water on the earth, and the total amount of freshwater that can be used by human beings only accounts for three-hundredths of the total water on the earth, accounting for the total freshwater storage. At present, more than half of the world's land area and more than 100 countries and regions are short of water, and 2 billion people have difficulty drinking water. Humanity is depleting water resources at a rate that doubles its freshwater demand every 15 years.

To date, human freshwater consumption accounts for 54 percent of the world's available freshwater. In other words, in another 50 years, mankind will face a situation where there will be no water to drink.

3. Water resources can be recycled, human freshwater resources are facing depletion, as long as water resources are protected and freshwater resources are rationally used in China, it is estimated that it can be used for about 300 years.

There is only a drop of water left, which is so good, only handsome guys and beauties will like it when they see it.