Migration of herbicides in the soil of agrophytocenoses and the possibility of managing the risk of contamination of environmental components

G.E. Larina¹*, L.M. Poddymkina²*, S.L. Belopukhov², R.F. Baibekov³ and I.I. Seregina²

¹All-Russian Research Institute of Phytopathology, 5 Institute Srt., RU143050 Bolshie Vyazemy, Moscow Region, Russia
²Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, 49 Timiryazevskaya Str., RU127550 Moscow, Russia
³Agrochemical innovation center for the development of agricultural science and production – 12 Kostyakova Str., RU127422 Moscow, Russia
*Correspondence:larina.galina2014@gmail.com, poddimkina@gmail.com

Abstract:

The migration of residual amounts of sulfonylurea and imidazolinone herbicides under conditions of washing water regime (sum of precipitation in forest and forest-steppe natural zone within 400–600 mm) in practice of intensive agricultural production has been studied. Vertical moisture transport in the soil determines the number of large pores, voids and cracks, and herbicide mobility depends on solubility of the active substance in water and adsorption equilibrium between the soil solution and the soil solid phase. The herbicide was applied to the soil surface, as is the case in practice. Then, pure water (without herbicide) was fed into the column from above, and the movement of water along the soil profile, as well as the adsorption of the herbicide by the soil and the desorption of the active substance by water, were simulated. The water supply to the column was stopped when the portions of water collected after filtering the water through the column contained less than the detection limit of herbicide residues chromatographically. The percentage content of sulfonylurea and imidazolinone herbicides residues in the soil solution varied depending on the nature of the active substance (maximum determined for imazapyr and lowest – metsulfuron-methyl) and soil type (more in acidic soil, compared to neutral and slightly alkaline soil). Effective management of pollution risks of the components of the natural environment (soil, surface and groundwater) provides a set of agrotechnological measures to reduce the number of large pores, voids and cracks in the arable layer.

Key words:

imidazolinone, pesticide, plant protection product, pollution of groundwater, sulfonylurea, vertical mobility in soil