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Introduction. The current challenges in water and agriculture management in Ukraine wield major influence on the development of reclamation science and practice. These challenges and the realities of irrigated farming require a revision of traditional decision-making methods and criteria to ensure resource-efficient irrigation management. Analytical and experimental studies were conducted to evaluate existing irrigation practices, develop a vision for its development over the next 20-30 years, and evaluate the prospects for the use of certain innovative products that can be implemented for irrigation management under existing economic conditions and in the future. The purpose of the research was to improve the methods of operational irrigation management and support the adoption of appropriate strategic decisions to achieve resource efficiency in irrigated agriculture. The following tasks were solved: to investigate the temporal and spatial variability of the natural and economic conditions of irrigation use; to determine the basic directions of models and algorithms improvement for operational irrigation planning taking into account the spatial and temporal variability of natural and economic conditions of real production; to evaluate perspective directions of development of irrigation planning methods to ensure resource efficiency of management in the current agricultural practice. Methods and methodologies. The research was conducted during 2012-2019 at the farms of Kherson and Zaporizhzhya regions. Testing and pilot implementation of the operational irrigation planning information system “GIS Polyv” has been carried out. The studies were carried out on 306 fields, the total area of which was 9266.09 ha, the main crops were soybean, sunflower, winter wheat, alfalfa and winter rape. Research methods included on-site observations, modelling, remote sensing, and method of system analysis. Results and discussion. The role of on-site and space agro-monitoring for the correction of bioclimatic coefficients of crop water consumption taking into account the space-time variability of the actual biomass has been substantiated and demonstrated. For the adaptation of irrigation management to the conditions of air drought, it is proposed to use an additional criterion for making decisions on crop cooling, which is determined by the maximally permissible temperature duration at the vegetation surface above the physiologically acceptable level. It is established that under conditions of air drought, in addition to slowing the growth of biomass, physiological processes occur in the leaves and reproductive organs of plants, due to the increase in the temperature of the vegetation surface. According to studies of energy transfer processes in crops during periods of atmospheric drought, an increase in the use of a share of thermal energy for turbulent exchange has been found compared to the volumes of energy that is evaporated. The vision of the future development of methods of operational irrigation planning based on modern agricultural information platforms has been presented.  It will allow to choose a method of operational irrigation management, based on the capabilities of each farm economy and to provide "on-line" consulting for water user organizations or farm personnel.

Relevance of the topic. In recent years, irrigation management practices have faced new challenges related to climate change and the increase in the frequency and intensity of droughts in the southern regions. In addition, the latest technical and technological capabilities have emerged in irrigated agriculture to more effectively manage technological processes. All these processes occurring in real production and in the market of scientific and technical products, have determined the possibility and necessity of studying the influence of natural and agricultural conditions on the processes of energymass transfer in the "soil-plant-atmosphere" environment to improve management methods in modern irrigation conditions. Purpose of research is to investigate the features of formation of crop thermal regime in the conditions of air and soil drought manifestation under irrigation during 2018-2019. Research object. The research was carried out at the production fields of the farm  “Freedom Farm International” in the Kakhovsky district of Kherson region during 2018-2019. Two experimental sites were equipped to carry out experimental studies on the crop rotation of "Gornostayevske -2". Methodology and Research methods. The methodology for the conduct of thermal water balance and phenological observations on the growth and development of crops at the experimental sites was applied. Standard field research techniques were used. Analytical, field, simulation modeling, mathematical statistics, geoinformation technologies (GIS), remote sensing of the Earth (RS) methods were used. Research results. As a result of the research in 2018-2019 a database of farm fields (crops, sowing dates, soil conditions, initial moisture reserves, irrigation machines and their characteristics) was created; phenological observations of plant growth and development were performed, heat and water balance calculations were made. It was established that to ensure optimal conditions for the use of thermal energy in different drought conditions, it is necessary to improve models and algorithms for operational planning of crop irrigation. Thus, to mitigate the influence of atmospheric drought, it is recommended to conduct refreshing irrigation, the timing of which can be determined on the basis of monitoring the temperature of the vegetation surface, using the data from the space images or ground-based observations. In addition, under drought conditions, in the case of applying water-balance methods used in irrigation management, it is necessary to adjust the biological coefficients of water consumption by crops, based on modeling the production process using the WOFOST model and identifying its parameters with the help of space images. The obtained new knowledge is aimed at improving irrigation management methods in modern conditions.

У статті наведено результати експериментальних досліджень зміни мікроклімату, розрахунків теплового та радіаційного балансу на зрошуваних полях при  вирощуванні сої пізньостиглої. Для проведення досліджень було облаштовано два експериментальні полігони загальною площею 1012,5 га, на яких встановлено автоматизовані метеостанції та виконували спостереження за станом та розвитком сільськогосподарських культур  на фоні двох сценаріїв планування зрошення – традиційного з регулюванням  вологості ґрунту у діапазоні 75-80-75%НВ та інтенсивного з підтриманням вологості  активного шару ґрунту в діапазоні 80-90%НВ. Встановлено, що інтенсивне зрошення (часті поливи невеликими нормами) сприяє покращенню мікроклімату у посівах  за рахунок більш ефективного поглинання теплової енергії та забезпечує більш високу продуктивність використання зрошувальної води.