The effect of microplastics on the variability of functional parameters of available water in loessial soils

Abstract Basic scientific research on microplastics and research paths on their fate in soil and water are essential for the studies of soil pollution in today’s world. However, our current knowledge of microplastics in soil is still not coherent, so it is necessary to create coherence, coordination and multi-faceted targeted studies for the sustainable management of soil ecosystems. In this paper, we examined the effects of soil texture in soils containing different weights of soil microplastics with special focus on water holding capacity. For this purpose, the effect of different weights of polypropylene microplastics, i.e. 0, 0.5, 1, 2 and 4 grams per kilogram of soil, on the amount of available water of three loess soil textures (silty loam, silty clay, silty clay loam) in a four-month period was evaluated. The experimental results showed the clear effect of microplastics on the water retention capacity in all three loess soil types under study, depending on the soil texture and weight doses of microplastics. The addition of microplastic concentration decreased the water holding capacity of silty clay soil to a greater extent than silty clay loam and silty loam. Thus, it seems that the addition of MPs to soils with higher clay content showed stronger effects on this soil property. This research showed the relationship between soil texture, weight doses of microplastics and soil functional parameters regarding soil water retention that may stimulate new ideas for future research and practical management practices for efficient application of water and fertilizers in agricultural fields of contaminated soils by microplastics.