Department of Environmental Geosciences, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500, Praha 6, Suchdol, Czech Republic.
Department of Water Resources, Institute of Hydrodynamics of the Czech Academy of Sciences, Pod Paťankou 30/5, 16612, Praha 6, Czech Republic.
Chemosphere. 2022 Apr;293:133586. doi: 10.1016/j.chemosphere.2022.133586. Epub 2022 Jan 12.
The soil hydraulic properties of two low-organic soils (Fluvisol; Regosol) were investigated following their amendment with biochar alone or in combination with manure, compost and co-composted biochar. Self-irrigating boxes containing the soil and amendment combinations were purposed with a battery of soil moisture sensors as well as soil porewater sampling devices. Static sampling determined bulk density, porosity and derived soil water retention curves. The aim of this study was to identify the most advantageous amendment combinations to enhance soil water retention whilst simultaneously avoiding excessive nutrient leaching arising, primarily, from manure application. Biochar significantly decreased bulk density and increased total porosity when compared to compost in the Fluvisol, whereas manure affected the greatest changes in the Regosol. All of the tested amendments adjusted the shape or extent of the soil water retention curves, but biochar addition resulted in the greatest increase (⁓50%) in easily available water content (for plants) in both soils, when compared to the control. Saturated hydraulic conductivity was, however, not changed by any of the amendments which reflects a lack of influence on infiltration. An enhancement in nutrient retention occurred in some of the soil amendment configurations, such as for co-composted biochar at 2% dosage and 5% manure-biochar mixture, as revealed by porewater analysis. In summary, the application of biochar with and without additional compost and manure can enhance soil water retention in low-organic soils whilst maintaining or enhancing nutrient retention. Such finding supports the application of mixed organic amendments to low-organic (and therefore drought-prone) arable soils.
研究了两种低有机土壤（淋溶土；淋溶土）在单独添加生物炭或与有机肥、堆肥和共堆肥生物炭组合添加后的土壤水力性质。自灌式盒子中装有土壤和改良剂组合，并配备了一系列土壤水分传感器和土壤孔隙水采样装置。静态采样确定了容重、孔隙度和衍生的土壤水分保持曲线。本研究的目的是确定最有利的改良剂组合，以提高土壤保水能力，同时避免主要由有机肥应用引起的过度养分淋失。与堆肥相比，生物炭在淋溶土中显著降低了容重并增加了总孔隙度，而粪肥在淋溶土中则产生了最大的变化。所有测试的改良剂都调整了土壤水分保持曲线的形状或范围，但与对照相比，生物炭的添加导致两种土壤中更容易获得的水分含量（植物）增加了约 50%。然而，任何改良剂都没有改变饱和水力传导率，这反映了它们对入渗的影响缺乏影响。在一些土壤改良剂配置中，如 2%用量的共堆肥生物炭和 5%的粪肥-生物炭混合物，通过孔隙水分析发现，养分保持能力增强。总之，生物炭与添加和不添加额外的堆肥和有机肥的应用可以提高低有机土壤的保水能力，同时保持或提高养分保持能力。这一发现支持了混合有机改良剂在低有机（因此易受干旱影响）耕地土壤中的应用。
