Improving water management technology in rice systems for sustainable rice production

Abstract

Purpose: to reduce rice irrigation rates by developing water management in rice systems for sustainable rice production. Materials and methods. The materials for the study were data obtained for 2020–2022 in production experiments in three experimental farms in Krasnodar Territory, the total area of which was 59,636 hectares. The idea of decreasing the irrigation rate by reducing the duration of flooding period, the number of discharges, the rate of one-time irrigation, the repeated flooding, the intensity of vertical filtration and physical evaporation is discussed. Water consumption, transpiration and seepage effluent were determined when defining the irrigation rate for the shortened flooding and the combined irrigation using the method of vegetation vessels with an area of 3000 cm². For an environmentally friendly technology, evaporation and transpiration were additionally determined using a GGI-500-50 evaporator at the stage of two or three leaves in rice crop during sprinkling irrigation. Results. The analysis (water-physical properties of soil, chemical analysis of soil samples, content of ferrous and ferric iron in soil) of existing (basic) rice cultivation technologies: shortened flooding and combined irrigation, was carried out. Integral curves of evaporation and evapotranspiration were constructed on the basis of observational data on vegetal discharge. Conclusions. A new environmentally friendly technology for rice cultivation was developed. As a result of evaluation the declared technology, its efficiency expressed in a reduction in irrigation rate by 10 % due to a decrease in evaporation, daily transpiration and vertical filtration was proven.