Soil water regime and crop yields in relation to various technologies of cultivation in the Kulunda Steppe (Altai Krai)

Abstract

This article presents the results of crop yield in areas with different technologies of cultivation based on the network of automatic stations that provide data on climatic and soil-hydrological monitoring in the dry steppe during the vegetation period of May–September 2013–2016 . These data on regional ecological and climatic parameters are of great interest to the ecologists, plant physiologists, and farmers working in the Kulunda Plain (Altai Territory). We compared the following options for cropping technologies: the modern system, which is the "no-till", technology without autumn tillage;the intensive technology of deep autumn tillage by plough PG-3-5 at a depth of 22–24 cm. Cultivation of crops was carried out using the following scheme of crop rotation: the modern system: 1–2–3–4 (wheat – peas – wheat – rape); the intensive system: 5/6 – 7/8 – 9/10 (fallow – wheat – wheat). We believe that the use of modern technology in these conditions is better due to exchange between the different layers of soil. When the ordinary Soviet system , the so-called "plow sole" , was used , at a depth of 24 cm , we observed that this creates a water conductivity barrier that seems to preclude the possibility of lifting water from the lower horizons. Results of the study of infiltration of soil moisture at the depth of 30 and 60 cm have shown in some years the advantages of the modern technology over the ordinary Soviet system: in the version with the use of modern technology we can trace better exchange between the various horizons and , probably, moisture replenishment from the lower horizons. Differences in individual observation periods are comparatively large due to the redistribution of soil moisture, depending on the weather conditions, the crops used in the crop rotations, and cultivation techniques. Moreover, the average moisture reserves within the one meter layer did not show any significant differences during the growing seasons of 2013–2016 . In terms of soil moisture usage and productive grain yield according to the four year experiment, the application of the modern technology with crop rotation "wheat – rape – wheat – peas" was more effective than the ordinary Soviet system with crop rotation "wheat – fallow – wheat – wheat". The four-year observation period is clearly insufficient to identify the advantages of the modern system, as during this time it is impossible to significantly improve soil quality indicators, which will continue to determine its water-retaining properties and moisture accumulation.