Innovative Technologies In The Assessment Of Accumulation And Erosion Processes In The Channels

The article discusses the possibilities of assessing the state of river beds and changes in them using remote sensing technologies (RS) and geographic information systems (GIS). With the help of geoinformation technologies, an assessment of deformation phenomena over the past 25 years in the channel of the Sokh river, which was chosen as the object of research, was given. Channel phenomena have been studied using data obtained from satellites. To analyze the situation, a model of the Landsat satellite was selected. The currently widely used official Glo Vis website was used to download the data. Data analyzed using ArcMap software. The results of the GIS data analysis were compared with the data of field studies. Over the past 20 years, along the channel, changes have been observed on the right bank, filling a part of the left bank with sediment particles, germination of moisture-loving plants and the process of erosion of the left bank. Over the past 5 years, about 30 meters of irrigated areas have eroded along the right bank between pickets PK3 and PK4. These changes average 5-6 meters per year. An analysis of the deformation processes occurring in the Sokh channel is carried out and conclusions are drawn.


Introduction
Impacts on the environment and processes related to climate change are also reflected in river basins. It is known from the analysis of the available literature and data on the processes in the riverbed that today the solution of these problems is carried out on the basis of many natural field studies [1,2]. Because the practical application of theoretical developments in this area requires rapid initial data. MOO and GAT technologies are among the most advanced methods in developed countries for fast and continuous data acquisition. Prompt response to emergencies and timely action are key issues. In the design of hydraulic structures built on the river, there is a need for scientific research aimed at improving the methods of hydraulic calculations, taking into account the changing factors in the river. One of the important tasks is the implementation of this task, including monitoring of the technical condition of irrigation systems and hydraulic structures, scientific research on improving the methods of remote accounting of water consumption based on resource-saving techniques, technologies [3,4,5].
Literature review and problem statement Today, the models created using GAT technologies in the Republic mainly provide the location of water resources and linear schemes of their mapping, do not create a database to determine the status of water resources, the mode of operation of hydraulic structures and accumulative and erosion processes in the river [6,7,8]. The main problem in the use of GAT models in the management and use of water resources is their low accuracy, the fact that the models are based on low-resolution satellite images, the use of old methods of analysis. In this regard, the study of changes in the riverbed and the technical condition of hydraulic structures using the technology of remote sensing (MOO) and geographic information systems (GAT) in irrigation systems is of particular importance [9,10,11]. Currently, more than 300 satellites are operating in space to solve the problems of economic sectors. They are all designed for a specific stage, and after launch into space, the possibilities are being tested in other areas as well [12,13,14]. Well-coordinated, geographically linked Landsat satellite imagery was used to study the state of accumulative and erosion processes in the riverbed. Landsat satellites are the first satellite system to appear in this space [15,16]. Landsat satellites have the ability to transmit data since 1972. However, the first Landsat 1-3 satellites are now sending poor-quality images to Earth due to the ingress of space dust into the scanner optics [17,18,19]. In this study, data from Landsat 4-8 satellites were used. Initially, data from the Soxsay River for the period 1995-2020 were downloaded from https:// earthexplorer.usgs.gov/. The data were analyzed using ArcMap software ( Figure 1).

Figure 1. Perform steps on data in ArcMap
Parameters of the Sokhsay river, which receives water from the Sarikurgan hydroelectric power station: the total length of the river is 9.4 km, the average width is 550 m, the average depth is 1.1 m, the average slope is i = 0.01. The maximum water consumption is up to 180 m3 and varies over the years. A distinctive feature of the Cox River is that the water flows in a certain part of the year. In the spring, water begins to flow into the riverbed in late May, and in some cases, water flows into the riverbed in early June and stops flowing into the riverbed in mid-September [20,21,22]. This movement of the flow makes it possible to increase the accuracy of the hydraulic measurements and the data obtained to a certain extent.

Outcome analysis and examples
In order to study the processes in the valley, 9 places along the length of the stream were selected. Changes in channel width and surface area have been observed in each place over the years (Table 1.2). According to the results of the last 25 years in the Sox River, the river has also changed its shape (Figures 2 and  3).   It can be observed that the width of the stream changed at almost every picket. At the same time, it can be seen that the width of the middle part of the riverbed has narrowed, and grasses and trees have grown in the sandygravel areas for 5 years. The main reason for this is that the flow changes its direction many times during the year and the amount of sediment moving in the flow structure is large. A similar situation can be observed in the last 5 years (Fig. 4.5).
It can be seen that the river has been washed along the right bank for the last 5 years. At the beginning of the 2nd stanza of the stream it can be seen that the stream is moving mainly on the right bank, and at the end of the 9th place, on the contrary, on the left bank. In order to study and investigate the deformation processes occurring in the riverbed, field research was conducted in the riverbed Sox. The data obtained as a result of the measurement work were analyzed. When the sox riverbed was inspected, it was observed that the initial part of the soybean was washed away (Fig. 6). The main reason for this is that the stream has changed its direction along the right bank. Over the last 20 years, there has been a change in the direction of the flow along the right bank, the river is filled with turbid particles on the left bank, grass growth and washing processes on the right bank. Figure 6. 35 picket of Sokh River, right bank During the last 5 years, it was observed that 30 m washed to the right bank in the range of 3-4 selected places. These changes average 5-6 meters each year. This is leading to the destruction of orchards and crops on the right bank.
Discussion and conclusion The study of problematic, accumulative and erosion processes in the river basin was based on the possibility of organizing on the basis of Earth satellites, thereby reducing the consumption of excess resources, increasing the accuracy of results, creating various models, databases, their application in agriculture and water management. The possibilities of geoinformation technologies in the assessment of erosion and accumulation processes in the valley were analyzed. In the study, GPS points were taken from 9 sections to study the deformation of the valley in certain sections of the Sokh River, and the geodetic position of these points was measured. These data provide the basis for future mapping of the river deformation, blurred printing, and washing model. It was seen as a solution to both economic and environmental problems. The implementation of the program based on GAT techniques and technologies will be a new direction for the rapid and accurate assessment of deformation processes in the riverbed, effective monitoring of water consumption. Based on the created maps, a database was formed and recommended for future work. As a result of research, time and resource savings have been achieved.