Borders of water bodies and their water protection zones in wetlands (based on the example of the Iksa river, Tomsk region, Russian Federation)

Relevance. Currently, there are a number of contradictions in defining the boundaries of water bodies, as well as special zones for their protection and use, because there is an urgent need for the correct establishment of such zones. In addition, the calculated probabilities for assessing the position of coastlines are not legally established. In this regard, the article examines the importance of reliably defining the boundaries of coastlines and river water protection zones in wetlands where there is the most contradictions. Aim. Comparative analysis of various methods for assessing the position of the coastline and the boundaries of the water protection zone of a river with a heavily swamped catchment. Methods. Statistical and cartographic methods, interpretation of space and aerial photographs. Results and conclusions. The authors have carried out the analysis of long-term data from routine hydrometeorological observations (1933–2007), materials from field surveys and interpretation of remote sensing data of the river Iksa section near the village Plotnikovo. It is shown that for this river the most rational way to assess the boundaries of a water body is to determine the average long-term maximum water level (the boundaries of the lower floodplain), and the boundaries of the water protection zone – by the maximum water level with a supply of 1% (the boundaries of the upper floodplain). These boundaries are quite noticeable during reconnaissance surveys during engineering studies and when using Earth remote sensing materials. All this increases the efficiency of environmental protection measures due to a more reasonable identification of water protection zones and makes it possible to optimize the methodology for determining their boundaries due to the use of these data instead of formal interpolation between observation points.