In 2023, in cooperation with the Institute of Hydrology Slovak Academy of Sciences, we measured the hydrophysical characteristics of soil samples from Senné (heavy clay soil) and Plavecký Štvrtok (light sandy soil) with different content of HUMAC® AGRO material.
The application of HUMAC® AGRO material to soil samples with heavy clay soil from the Senné locality resulted in a change in the basic physical properties of the soil. A higher dose of HUMAC® AGRO caused a decrease in specific gravity by 0.18%. The bulk density decreased by 1.76-3% and the porosity increased by 1-2.82% compared to the clean soil. Heavy soils were lightened and their pore volume increased. The effect of HUMAC® AGRO material batch size was manifested in saturated hydraulic conductivity values, which decreased by 5.3-35.5%. This means that the material slowed down the flow of water through the samples and the infiltrated (soaked) water remained in the soil for a longer time. Based on the measurements of the moisture retention curves, an increase in the maximum water (retention) capacity after the addition of HUMAC® AGRO is evident in the range of 0.2 – 1.12% (1% = 1 litre of water per m2). At the same time, the range of usable water capacity was expanded by 0.45-1.24%. The improvement of the retention properties of heavy soils after the application of the material HUMAC® AGRO consists mainly of improving the mobility and energy availability of water.
In the samples of light sandy soil from Plavecké Štvrtek, in contrast to the heavy soil, the size of the applied dose of HUMAC® AGRO material had a greater effect on the measurement results. There was a drop in specific gravity by 0.23-1.82% and bulk density by 1.33-4.28%. The porosity increased by 0.83-1.56% compared to the clean soil. There was also a decreased saturated hydraulic conductivity by 11.4-15.8%. In natural conditions, this means that in sandy soil with an admixture of HUMAC® AGRO material, the water flow slows down. The absorbed water therefore remains in the soil for a longer time, which is a positive phenomenon, especially in light sandy soils. The maximum retention capacity also increased by 0.61-2.58% and the usable water capacity by 0.01-0.18% with the addition of the material. Again, it can be concluded that the application of the material HUMAC® AGRO improved the retention properties of sandy soil, primarily by increasing the retention capacity and expanding the range of usable water capacity compared to clean soil.
The investigated material can influence the hydrophysical properties and thus also the water regime of soils.
More in original scientific publication:
Kandra, B., Tall, A., Vitková, J., Procházka, M., and Šurda, P. (2024) “Effect of humic amendment on selected hydrophysical properties of sandy and clayey soils”, Water, 16(10), p. 1338. Available at: doi.org/10.3390/w16101338.
