Выполнена математическая формализация уравнений модели, для построения которой использовалась концепция системы ресурспотребитель. В рассматриваемом случае потребителем выступает биомасса растений, а ресурсомраспределенные в узкой прикорневой зоне растений основные элементы его минерального питания (азот, фосфор и калий). Динамические уравнения модели следуют основному положению химической кинетики, согласно которому результат взаимодействия динамических переменных в системах рассматриваемого профиля определяется их произведением. Выполнена оценка параметров и установлена адекватность модели выборочным распределениям. В качестве выборочных распределений используется массив экспериментальных данных роста яровой пшеницы (Красноуфимская-100) на торфяной низинной почве, предварительная почвенная обработка которой проведена с помощью азотных, фосфорных и калийных удобрений.
Modern mathematical models for the simulation of dynamics in the fertilizer-soil-plant system, the components of which are agricultural plants, soil microorganisms and elements of their mineral nutrition, are considered. Based on the analysis of the adopted provisions, a model that takes into account the relationships and the specific nature of the joint changes in its components has been developed. The mathematical formalization of the model equations is carried out, for the construction of which the concept of the resourceconsumer system was used. In this case, the consumer is the biomass of plants, and the content of the main elements of its mineral nutrition distributed in the narrow basal zone of plants is a resource. The dynamic equations of the model follow the basic principle of chemical kinetics, according to which the result of the interaction between dynamic variables in the systems of the profile in question is determined by their product. The equations also contain the self-limitation factor, which sets the growth rate of the curve for the logistic equation and the specific rate of the model variables saturation effect. Thus, the specific rate of change in biomass is determined by its natural growth rate, the weighted sum of the nutrient contents in plants, and intraspecific competition. The rate of change in the content of these elements per unit of biomass is proportional to their current content in the rhizosphere and to the factor of the mutual influence of the elements on each other. The parameters are estimated and the adequacy of the model to sample distributions is established. An array of experimental data on the growth of spring wheat (Krasnoufimskaya-100) on peat lowland soil, the preliminary soil treatment of which was carried out using nitrogen, phosphorus, and potassium fertilizers, is used as sample distributions. The coefficients obtained as a result of parameter estimation and the calculated distributions of model dynamic variables with a sufficiently high degree of adequacy correspond to their experimental distributions and reflect the real situation of the system evolution.
PENENTUAN DENSITAS SPESIES PLASMA HIDROGEN PADA KESETIMBANGAN TERMODINAMIK TEKANAN ATMOSFIR MENGGUNAKAN MATLAB
