What do people often mean by water?

In geography, water resources are usually freshwater resources that can be used directly by human beings.

Water and water bodies are two different concepts. Pure water is made up of H2O molecules, and water bodies contain a variety of substances, including suspended solids, aquatic organisms, and substrates. A water body actually refers to a natural complex of areas of the earth that are covered by water, including rivers, lakes, swamps, reservoirs, glaciers, groundwater, and oceans, among others.

Water resources are very closely related to human beings, human beings regard water as the source of life, and human beings have always concentrated in places where there is water and carried out economic activities in the course of historical development. With the development of society and the advancement of technology, human beings are becoming more and more dependent on water. Water is the most widely distributed and abundant resource in the world.

Water covers more than 70 percent of the Earth's surface, totaling 1.5 billion cubic kilometers; It is also the most exploited resource in the world. Humanity now consumes far more water than any other resource each year, with 3 trillion tonnes of water used worldwide. Water resources on Earth are unevenly distributed, with precipitation and runoff varying widely from place to place.

About one-third of the world's land area is dry and rain-scarce, while other regions are prone to flooding during the rainy season. For example, in China, the Yangtze River basin and its southern areas account for more than 82 of the country's water resources, 36 of the cultivated land, and more water and less land; In the area north of the Yangtze River, cultivated land accounts for 64 percent, water resources are less than 18 percent, and there is more land and less water.

Water is a resource because of its physical, chemical and natural properties. There are broad and narrow senses of water resources, and usually when we talk about water resources, we mean water resources in the narrow sense. Water resources in the broad sense Water resources in the broad sense refer to the water that is widely present on the earth's surface and in the earth's lithosphere, atmosphere, and biosphere in solid, liquid, and gaseous forms in nature, and is the total amount of water on the earth, including seawater.

The earth we live on is a planet of water, oceans, rivers, lakes, streams, ......Through the hydrological cycle, they are interconnected and influence each other, and together they form a complete hydrosphere of the earth, which is the birthplace of life. In this sense, any water in the hydrosphere has direct or indirect use value for human beings and can be regarded as water resources. It includes both renewable and non-renewable water resources.

Water Resources in the Narrow Sense Water resources in the narrow sense are water that is concentrated in rivers, lakes, glaciers and aquifers buried in shallow underground during the water cycle. It is more than atmospheric precipitation, can be replenished and renewed year by year through the water cycle, and is easily used by humans, including surface water, groundwater and soil water. Among them, surface water is rivers, glaciers, lakes, swamps and other water bodies; Groundwater is the dynamic volume of groundwater catchment; Soil water is water dispersed in a loose surface layer on the lithospheric surface.

Water resources mainly include the following: water resources in a broad sense refer to all forms of water in nature, including gaseous water, liquid water and solid water; Water resources in the narrow sense refer to natural fresh water that can be directly used by human beings and can be continuously renewed. This mainly refers to surface water and groundwater on land.

Water resources are water sources that are available or likely to be used, in sufficient quantity and of appropriate quality, to meet the specific needs of a place over a period of time. According to the definition of water resources in the water conservancy science and technology terminology published by the National Committee for the Examination and Approval of Scientific and Technological Terms, water resources refer to the water on the earth that has a certain quantity and available quality that can be supplemented from nature and can be used.

On Earth, water, which can be used directly or indirectly by humans, is an important part of natural resources. Natural water resources include river runoff, groundwater, snow and glaciers, lake water, swamp water, and seawater. According to the water quality, it is divided into fresh water and brackish water.

With the development of science and technology, the use of water by human beings has increased, such as seawater desalination, artificial catalytic precipitation, and the use of Antarctic slag to resist land ice.

Due to changes in climatic conditions, the spatial and temporal distribution of various water resources is uneven, and the amount of natural water resources is not equal to the amount of available water.

Unlike other natural resources, water is a renewable resource that can be reused multiple times; and intra-annual and inter-annual volume changes, with certain periodicity and regularity; The form of storage and the movement process are affected by physical geographical factors and human activities.

The Earth's water resources, broadly speaking, refer to the total amount of water in the hydrosphere. It includes surface water and groundwater that are controlled by humans and can be directly used for irrigation, power generation, water supply, shipping, aquaculture, etc., as well as rivers, lakes, wells, springs, tidals, harbors and aquaculture waters. Water resources are indispensable and important natural resources for the development of the national economy.

In many parts of the world, demand for water is already outstripping its capacity, and many regions are on the verge of imbalances in water use.

Water is an indispensable and important substance for the survival of human beings and all living things, and is an irreplaceable and extremely valuable natural resource for industrial and agricultural production, economic development and environmental improvement. Although the term "water resources" appeared earlier, with the time of the Cherish Water Poster.

The connotation of generation progress is also constantly enriched and developed. However, the concept of water resources is both simple and complex, and its complex connotations are usually manifested in: there are many types of water, with movement, and various water bodies have the characteristics of mutual transformation; Water is used in a wide range of uses, and each use has different requirements for its quantity and quality; The "quantity" and "quality" contained in water resources can be changed under certain conditions; More importantly, the development and utilization of water resources is constrained by economic, technological, social and environmental conditions.

Therefore, people's understanding and experience from different perspectives have led to inconsistencies in the understanding of the term water resources and differences in understanding. At present, the concept of water resources can be understood as the amount of water that has both quantitative and qualitative requirements for long-term survival, life and production activities, including use value and economic value. The concept of water resources is generally considered to be broad and narrow.

In a broad sense, water resources refer to all kinds of water and substances in water that can be used directly or indirectly, and water with use value and economic value for human activities can be called water resources. Water resources in a narrow sense refer to fresh water that can be directly used by human beings under certain economic and technological conditions. The water resources discussed in this book are limited to a narrow scope, that is, freshwater resources that are closely related to human life and production activities and social progress.

World water resources, in a broad sense, refer to the total amount of water in the hydrosphere. Since seawater is difficult to use directly, we mainly refer to freshwater resources on land. Through the water cycle, fresh water on land can be continuously renewed and replenished to meet the needs of human production and life.

Scarce water resources refer to natural fresh water that can be directly used by human beings and can be continuously renewed. This mainly refers to surface water and groundwater on land. The annual recharge of freshwater bodies is usually used as a quantitative indicator of water resources, for example, the dynamic water volume of surface water bodies such as rivers, lakes and glaciers is used to represent the surface water resources, and the dynamic water volume of underground saturated aquifers is used to represent the water resources under the ground in front of the ground.

What are the correct statements about water resources?Canada and Russia have abundant water resources, but some areas of the town are also experiencing water stress due to water pollution.

According to the definition of water resources in the World Meteorological Organization (WMO) and the United Nations Educational, Scientific and Cultural Organization (UNESCO) International Glossary of Hydrology, 3rd edition, 2012, water resources are water sources that are available or likely to be used, in sufficient quantity and of appropriate quality, to meet the specific needs of a place over a period of time.

According to the definition of water resources in the water conservancy science and technology terminology published by the National Committee for the Examination and Approval of Scientific and Technological Terminology (Science Press, 1997), water resources refer to the water on the earth that has a certain quantity and available quality that can be replenished from nature and can be used.

In 2021, China's total annual water resources were 2,952 billion cubic meters.

According to the definition of water resources in the World Meteorological Organization (WMO) and the United Nations Educational, Scientific and Cultural Organization (UNESCO) International Glossary of Hydrology, 3rd Edition, 2012, water resources are water sources that are available or likely to be used, in sufficient quantity and of appropriate quality, to meet the specific needs of a place over a period of time.

The concept of water resources is often broadly and narrowly defined.

In a narrow sense, it refers to freshwater that can be directly used by humans, that is, in the process of natural water cycle, atmospheric precipitation falls to the ground to form runoff, which flows into surface water in rivers, lakes, swamps and reservoirs, and groundwater that seeps into the ground. People use it to meet the needs of industrial, agricultural and domestic water, and the amount of water resources is generally expressed in terms of runoff.

In a broad sense, it refers to all kinds of water and water substances that can be used directly or indirectly by human beings, and water with use value in social production can be called water resources. It includes all freshwater and brackish water on Earth, both natural and renewed, as well as water that has been treated by humans using engineering or biological measures.