ASSESSMENT OF CHANGES IN THE INTRA-ANNUAL FLOW DISTRIBUTION OF THE SYRDARYA RIVER

The Syrdarya River is the second largest river in the Aral-Syrdarya basin. It flows through the densely populated southern region of Kazakhstan and flows into the Aral Sea. The available water resources of the river are mainly used for irrigation of agricultural land. The main obstacle to the development of this branch of the economy is the lack of water in some parts of the massif, especially in its lower reaches. The article is devoted to the water regime currently forming in the lower reaches of the Syrdarya River, and the assessment of the change in runoff over the year. In modern conditions, as a result of the influence of economic activity on the flow of the Syrdarya River, it is difficult to clearly determine the type of river nutrition. It follows from the analysis that in all seasons of medium and low (low) water content, the values of the flow volume are close to each other. Also, the intra-annual flow distribution differs from the Central Asian rivers of a natural nature. For example, if in the natural conditions of the river the greatest Runoff is observed in March-July, then in modern conditions the period of abundant water falls on the winter period – November-February. The average monthly minimum water flows occur during surface irrigation of cultivated areas, that is, in the summer months, and in the fall there is abundant irrigation of rivers. The large Toktagul and Andijan reservoirs built in the upper reaches of the river for irrigation purposes also have a great influence on the intra-network distribution of runoff and the dynamics of its fluctuations. This is due to the fact that currently these reservoirs are actually used for energy purposes. In addition, in recent years, the Koksarai counterregulator has been built along the Syr Darya River in Kazakhstan.The main purpose of the study is to clarify the intracellular distribution of runoff in the lower reaches of the river in such difficult hydrological conditions in the river basin.