Water is one of the most important components of our life. Speaking of water, one should not forget about such a concept as water balance. Let's start with a definition.
Water balance - the ratio of income, changes in water supply and its consumption in a certain period of time. It takes into account all the water on Earth in liquid, gaseous and solid state. For land (which has a runoff to the ocean), evaporation is numerically equal to the quantitative value of precipitation, if we subtract river and underground runoff from them. And for the oceans - the sum of atmospheric precipitation, river runoff and groundwater inflow from the continents. If we talk about closed (drainageless) land areas and about the entire Earth as a whole, then evaporation correlates with precipitation.
This is a very important indicator, so a special equation has been derived for it, which calculates the water balance, which is used to carry out the balance assessment. In this way, the volumes of renewable water resources in vast areas remaining as a result of the water cycle in nature are calculated. This indicator is also determined for lakes, rivers, oceans and soil.
The water balance of the lake is determined based on the inflow of atmospheric precipitation, groundwater and surface water, taking into account changes in the water level in the lake in the time interval of interest. The water balance of reservoirs is calculated according to the same principle. The use of river, lake and groundwater for the purposes of water supply for the population and industry, irrigation of plants significantly changes the ratio of the water balance and its elements. Its calculation is also necessary for the implementation of many practical actions: forecasting the inflow of water into mines, quarries, designing and working on measures to manage the water regime. In many ways, the water balance is influenced by natural long-term and seasonal fluctuations, but even more so by changes as a result of active human activity. Water balance elements are measured at hydrometeorological and hydrogeological stations.
There is also such a thing as a water balance - the ratio between the inflow and flow of water on a certain part of the earth's surface for a period of interest when taking into account human economic activity. This indicator helps to analyze and assess the water availability of the basin. In the event that the balance has a negative indicator, we are talking about the need to take measures to cover the water deficit.
Soil water balance is a proportional ratio of the amount of water that enters the soil and that which is consumed from it over a certain period of time. It is calculated if necessary to find out the level of water supply of local plants. Depending on the ratio of the measured variables, the mode is defined as:
- frozen;
- flush;
- periodically flushing;
- non-flushing;
- effusion;
- irrigation.
The concept of "water balance" is also used to assess the state of the human body, namely the water content in the blood and cells. This is a very important indicator, the normal well-being of a person, the metabolic rate and the absorption of nutrients depend on it.
