Dynamics of matrix pressure in constructed soils on newly created agricultural landscape of a solid wastes landfill

Abstract

The dynamics of productive moisture and matrix pressure for constructed soils of newly created agricultural landscapes on the territory of a reclaimed solid wastes landfill are discussed. Three variants of constructed soils consisting of medium-loamy chernozem, sewage sludge and their mixtures were studied. All variants of constructed were divided into areas with irrigation and without irrigation. Under the same external conditions, moisture deficiencies are observed in the “soil: variant without irrigation, while there are no such conditions in the “sewage sludge” and “soil + sewage sludge” variants. With irrigation introduced, while maintaining a pre-irrigation moisture level of 60% of the lowest moisture capacity, there are no critical conditions and moisture deficiency in all studied variants of constructed soils. The study also shows that the matrix pressure in constructed soils depends on their composition and moisture capacity. The upper layer of the constructed soil of the “soil” variant has a high pressure which may be critical for plants, while in the lower layer of the same constructed soil the pressure is lower. The constructed soil of the “mixture” variant also showed different pressures in different layers. In the constructed soil of the “sewage sludge”, a high pressure level in the second half of the growing season was recorded in the middle layer, while the upper and lower layers were characterized by relatively low pressure. When maintaining the moisture level in the structural soils at 60% of the minimum moisture-holding capacity, the dependence on the composition and moisture capacity of the obtained constructed soils is revealed.