The dissertation is devoted to the problem of the impact of climate change on the cultivation of crops, which causes a significant loss of crops in countries with large areas of arable land. Increased precipitation variability and high temperatures are key factors that are expected to have a significant impact on Ukraine's agricultural production. For the study, a cereal crop known as the "cool season" crop was selected - oats (Avena sativa L.). Changes in humidity and climate change will be most noticeable in arid and semi-arid regions of our country, which also includes the steppe zone of Ukraine, which requires early assessment and modeling of future impacts of agrometeorological conditions in order to take the necessary agronomic measures. The aim of the dissertation research was to assess the influence of agrometeorological conditions on the morphogenesis of oats and photosynthetic productivity of this crop in the conditions of climate change for the territory of the Steppe zone of Ukraine.
The paper uses modern methods of mathematical modeling of plant growth and development in different growing conditions under the influence of environmental factors; theoretical analysis of modern mathematical metameric models; statistical processing of agrometeorological and climatic characteristics; geographical generalization of growing conditions and the quantities that determine them; cartographic methods of presenting the received information.
The influence of agrometeorological conditions on photosynthetic productivity of culture, formation of vegetative and reproductive sphere of sowing oats in the conditions of the South of Ukraine is experimentally investigated in the work; regularities of influence of agrometeorological conditions on formation of stalks of oats as difficult set of growth of metamers of stalks are established; a spatial model of plant-Morph-Mod oat shoot morphogenesis is proposed. The parameters of this model were identified and its adequacy was checked. The following are established: regularities of changes in the intensity of transpiration, photosynthesis and daily productivity of plants in conditions of progressive drought; patterns of growth of "flag" leaves of the oat plant, the photosynthesis of which plays a significant role in the formation of grain yield.
The basic dynamic model of the plant production process was modified and adapted in relation to the culture of oats and the parameters of this model were identified in relation to the soil and climatic conditions of the Steppe of Ukraine; a comprehensive assessment of the conditions of heat and moisture supply of the territory is provided cultivation of oats in the Steppe of Ukraine in the conditions of climate change according to climatic scenarios RCP4.5 and RCP8.5, the estimation of influence of change of agroclimatic conditions of cultivation of culture on photosynthetic productivity of sowing oats is received. An assessment of the impact of future climate change on oat yields in the steppe zone of Ukraine is given.
The introduction includes the relevance of the topic of the dissertation, scientific novelty and practical value of the results. The established patterns of influence of agrometeorological conditions on growth and development of plants are the basis for operative assessment of conditions of formation of productivity of oats. In accordance with the set goal, the main tasks of the work were determined, as well as the object and subject of research. Also in the introduction the personal contribution of the applicant, approbation and publication of results of the dissertation and structure and volume of work are presented.The first chapter is devoted to the general characteristics of the study area - the steppe zone of Ukraine, as well as a brief description of the biological characteristics of oats. The physical-geographical characteristic is given, the data on features of zonal complexes and climatic conditions of the territory of research are resulted. It is noted that this area is divided into three subzones: northern steppe, middle steppe and southern steppe (dry steppe) according to the peculiarities of humidification conditions, thermal resources, the nature of soil cover, as well as the peculiarities of agricultural use. The chapter presents the layout of 28 meteorological stations, the data of which were used to establish the pattern of influence of agrometeorological conditions on the formation of productivity of oats, as one of the most common and important cereals in Ukraine. Yields of oats with high cultivation techniques and favorable weather conditions are relatively high, but in years with insufficient rainfall, their productivity decreases sharply.
