Water-soluble organic matter in the soils of the slope agrolandscape of Krasnoyarsk forest-steppe

In the study experimental materials according to the contents and dynamics of water-soluble organic matter in agrochernozyoms and their dependence on the properties of soils and vegetable remains were considered. The researches were conducted on the slope agrolandscape (catena) on the training farm of "Minderlinskoye" located in the central part of Krasnoyarsk forest-steppe. Trial areas were marked on the plaky part of the slope (1 pp - eluvial type of the agrolandscape), the middle slope of the slope (2 pp - transeluvial type of the agrolandscape), the lower part with the microfalls of the slope part (3 pp - transeluvial-accumulative type of agrolandscape) and a large saucer-shaped depression or depression (4 pp - trans-cumulative agrolandscape type) in the slope of this slope. The trial areas 1 and 2 were characterized by ordinary chernozyoms in a complex with lixivious, 3 - the meadow and chernozyom soil, 4 - the chernozyom and meadow soil. Soil samples for definition of stocks of vegetable remains and the content of carbon of organic substance were selected 3 times for a vegetative season of 2015-2016 from depths 0-5, 5-10, 10-20, 20-30 cm. The amount of gross carbon (Slope) was determined by Tyurin's method, water-soluble (Arch) -bichromated oxidability method in water extract at the ratio 1 (soil): 5 (wa-ter). It was shown that chemical fractionation of organic substance of soils water extract allowed to take only part of an active pool, about 1 % from the slope. Among soils of chernozyom and meadow> meadow and chernozem> ordinary chernozyom was observed gradual, statistically not significant, reduction of the pool of the arch. The content of water-soluble organic substance in 0-30 cm layer of soils was rather stable. Interdependence be-tween the quantity and quality of the vegetable re-mained coming to the soil and the content of water-soluble organic substance was established. The pool of water-soluble organic substance increased in soils with higher stocks of vegetable remains. The reduction of receipt of fresh vegetable remains led to the decrease in stocks of water-soluble OM.