The objective of the research was to study the effect of meteorological conditions, fertilization and watering on the moisture of model soils and plant yields in the lysimetric experiment.
Исследования, проведенные в годах 1978-1981 в срандомизированной схеме, касались влияния интервенционного орошения на водный режим почв. На основании полученных результатов можно определить механизмы, вызывающие исследуемые эффекты. Главным выводом было установление, что малые оросительные дозы по отношению к чрезмерно просушенным почвам, могут вызывать дальнейшее, опасное последствиями, понижение состояния их увлажнения.
In 0.8 m² microplots, a very poor sandy soil that contained only traces of organic matter was enriched with bentonite (BNT) at rates of 0, 3, 6, and 12 kg/m² . For 30 years the microplots were planted with different crops and regularly enriched with mineral and organic fertilizers. For the next eight years the microplots were left barren. The soils with BNT added contained significantly higher amounts of organic carbon (OC) and total nitrogen than the control soil (CS). Furthermore, in comparison to CS, organic matter in the soil with 12 kg/m² of BNT contained significantly more humins. Such durable stabilization of OC by BNT can be important for processes of carbon sequestration in soil.
Bentonite has been recognized as a very good material for the improvement of coarse textured soils. In microplot experiment, of a sandy soil deprived of the humus layer was enriched in 1973 with waste bentonite at the rates of 0, 3, 6 and 12 kg m -2 . Until 2002, the microplots were planted with different crops and regularly enriched with mineral a nd organic fertili zers. Since 2003, the microplots were left barren. In 2009, determinations of several features of the soils (in 5-30, 30-55 and 55-80 cm layers) showed that the historical amendment of the sandy soil with bentonite (especially its highest dose) ensured significantly higher contents of water, organic C, clay, silt and a sand fraction with particle diameter <0.1 mm in 5-30 cm layer. Proportions of non-dispersible clay in the total clay of bentonite soils in the two upper soil layers were significantly lower than those of the control soil. A significant increase in the penetrometer resistance was observed in 40-58 cm layers of the control soil and the soil with 3 kg m -2 bentonite amendment, contrary to the soils with two highest bentonite doses.