Long-term Studies of the Hydrothermal Regime of Agrocenoses and a Combined Irrigation System for Its Regulation

Abstract

The purpose of this study is to develop combined irrigation systems for effective regulation of the hydrothermal regime of soil, plants, and the surface layer to create optimal conditions for plant growth and development. The fundamental methodological approach to creating combined irrigation systems is the combined use of different irrigation methods and their implementation in a special regime within a single technological process. Another key point is that irrigation is carried out in different ways on the basis of a single technical system, which is an independent design solution. The creation of these engineering systems is the starting point for the transition to new reclamation technologies providing an integrated regulation of life factors and an extended protection of agricultural crops from climate risks in open ground conditions. The research substantiates the necessity and technical feasibility for combining fine sprinkling irrigation of agricultural crops with other known methods of irrigation, such as drip, sprinkling, subsoil, and surface irrigation methods. Fine sprinkling covers the vegetative organs of plants with 100–400 μm drops, followed by their evaporation and the absorption of latent vaporization heat, which makes it possible to effectively regulate the microclimate in the sowing medium. During evaporation, water cools the leaf surface by 5–7°C and increases the actual humidity of the surface air by 14–16%, thereby removing peak temperature stress and improving the physiological state of the plants. However, under arid climate conditions with a severe shortage of natural moisture supply, fine sprinkling does not make it possible to compensate the demand of plants for water and does not regulate soil moisture reserves. This makes it necessary to combine the use of fine sprinkling with irrigation methods for soil moisture regulation.