Rivers and streams are special ecosystems of flowing waters. The organisms that live here have adaptations to life in conditions of water mobility. Unlike other ecosystems, rivers are distinguished by the fact that in them the source of energy is organic matter coming from terrestrial and lake ecosystems.
It is very difficult to overestimate the importance of rivers in human life and the planet as a whole. It is enough to estimate how much water humanity spends per year to be convinced of this. And this volume exceeds 3.5 thousand cubic kilometers and is increasing annually. In ancient times, rivers served as the most important means of communication, so most cities were built precisely near large rivers. Today, the river has lost its significance as the main trade route, but its significance remains enormous. The river is the main source of fresh water needed in everyday life for agriculture and industry. The river remains an important transport route, allowing the transport of both people and goods. During the construction of hydroelectric power stations (hydroelectric power stations), giant dams block the rivers, and huge turbines generate the electricity needed by man through the movement of water. The river is the most important recreational resource that is used in the process of restoration and development of the physical and spiritual forces of a person, his ability to work and health. Most world resorts are located near rivers or seas. The river is a fishing place.
Lakes are reservoirs with stagnant, in most cases fresh water. In them, life is most diversely represented in the coastal zone.
The lakes regulate the flow of rivers, detaining meltwater in their hollows and giving them away in other periods. Chemical and biological reactions occur in the waters of the lakes. Some elements pass from water to bottom sediments, others – vice versa. In a number of lakes, mainly lacking runoff, the concentration of salts increases due to the evaporation of water. The result is a significant change in the salinity and salt composition of the lakes. Due to the significant thermal inertia of the water mass, large lakes soften the climate of the surrounding areas, reducing annual and seasonal fluctuations of meteorological elements.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.