Using Geoinformation Systems to Study the Duration and Standards of Flooding in the Estuary Area in the Urals

When creating a digital terrain model (DMM) of the territory of estuary No. 50, a survey using a Spector S65 satellite receiver in combination with a base station was used. 4 sites were allocated and coordinated on the ground, located on 4 tiers with flooding rates of 2500-3000 m3/ha, 3000-3500 m3/ha, 3500-4000 m3/ha, 4000-4500 m3/ha. The open source Quantum GIS (QGIS) program was used to work with satellite images, which allowed managing geodata, displaying, editing and analyzing them, as well as creating map layouts. QGIS supports many vector and raster formats, as well as various databases. The NDWI (Normalized Difference Water Index) index was used to identify and highlight areas flooded with water or areas in a wet state on a satellite image against the background of soil and vegetation, which made it possible to determine the duration of the standing water time in the selected areas.Analysis of soil samples in the spring showed that the content of productive moisture in the meter layer on the variants ranged from 188.2 mm at 2500-3000 m3/ha to 285.8 mm at 4000-4500 m3/ha, with an indicator on the control (non-flooded area) of 121.1 mm. By the time of harvesting the plants, the reserves of productive soil moisture also differed between the variants, ranging from 78.5 mm (2500-3000 m3/ha) to 103.2 mm (4000-4500 m3/ha)