Dynamics of species diversity of weeds in agrophytocenoses

Modern farming systems must ensure profitable crop production and biodiversity conservation. This is an important problem of our time. For its solution, it is advisable to study dynamics of species composition of agrophytocenoses, which formed against the background of application of different agrotechnical measures. The aim of our research was to study the dynamics of weed species composition in agrobiocoenosis on model fields. For this purpose, the species diversity of weed plants in agrophytocenoses was analysed, taking into account their biological groups. Monitoring of weed plants was carried out in the period from 2004 to 2024, using the method of sample plots in the fields and route method along the field edge. Due to the surveys, 71 species of weeds were detected, among which spring weeds, most often rhizomatous and rhizomatous weeds, had the maximum species diversity. Maximum abundance was observed in spring weeds (Ambrosia artemisiifolia L., Amaranthus retroflexus L.) and rootstock perennials (Convolvulus arvensis L.). Prolonged use of manual weeding has a negative cumulative effect on field conditions, which is manifested in gradual accumulation of rootworms (Сonvolvulus arvensis L., Lactuca serriola L. C.A. Mey, Cirsium vulgare Ten., Cirsium arvense Scop., Lactuca tatarica (L.), Sonchus arvensis L.), rhizomatous (Euphorbia virgate Waldst. and Kit, Elytrigia repens (L.) Nevski) and late spring weeds (Ambrosia artemisiifolia L., Amaranthus retroflexus L.). Mechanical tillage (disc harrow and cultivator) with the use of herbicides effectively reduces the species diversity and abundance of weeds in the fields that have been converted to fallow and allows getting rid of Ambrosia artemisiifolia L., but without the use of herbicides, it reappears in the fields.