An ever-increasing amount of microplastics enters the environment and affects soil properties and plant growth. Investigating how the interactions between microplastics and soil properties vary across different soil types is crucial. In sandy soil, the subcritical SWR induced by microplastics may affect other soil properties. The objective of this study was to assess the impact of adding three types of microplastics (high-density polyethylene, polyvinyl chloride, and polystyrene) at a concentration of 5% (w/w) to sandy soil on the persistence and severity of SWR, as well as on various soil properties (bulk density, water sorptivity, and hydraulic conductivity) and plant characteristics (fresh and dry weight, maximum photochemical efficiency of PSII, and nutrient content) of radish (Raphanus sativus L.). It was found that microplastic contamination increased the persistence and severity of SWR and decreased soil bulk density, water sorptivity, and hydraulic conductivity. The total biomass measurements did not reveal a significant difference between the microplastic treatments and the control group. This study did not confirm any significant influence of microplastic contamination on the maximum photochemical efficiency of PSII, a measure of crop photosynthesis. Even though the value of photosynthetic efficiency changed with time, the values for all treatments stabilised at the end of the experiment. Microplastic contamination did not significantly alter crops’ nitrogen, phosphorus, potassium, or zinc contents. However, the copper content was reduced in all treatments, and magnesium and iron were reduced in the PVC and PS treatments compared to the control. The microplastic-induced changes in biomass or photosynthetic efficiency do not correspond to the changes in crop element concentrations.
23 August 2022 in Journal of Hydrology and Hydromechanics
Microplastics (particles of plastics <5 mm) affect the physical, biological and hydrological properties of agricultural soil, as well as crop growth. We investigated the effect of the addition of three microplastics (high-density polyethylene (HDPE), polyvinyl chloride (PVC), and polystyrene (PS)) at a concentration of 5% (w/w) to a silty loam soil on selected soil properties and growth of radish (Raphanus sativus L. var. sativus). Changes in the soil properties and radish growth in three microplastic treatments were compared with the control. Soil properties (bulk density, hydraulic conductivity, sorptivity, water repellency) were estimated for each treatment at the beginning and at the end of the radish growing period (GP). The bulk density was significantly lower in the HDPE and PVC treatments compared to the control within the measurement at the beginning of the GP and in all microplastic treatments compared to the control at the end of the GP. The values of hydraulic conductivity and water sorptivity did not show significant differences between any treatments within the measurement at the beginning of GP, but they were significantly higher in the HDPE treatment compared to the control at the end of the GP. The growth of radish was characterized by the plant biomass and effective quantum yield of Photosystem II (Y (II)). We did not find a statistically significant difference in the total biomass of radish between any of the experimental treatments, maybe due to used concentration of microplastics. The mean value of Y (II) was significantly higher in all microplastic treatments compared to control only within the last measurement at the end of the GP. A statistically significant change of Y(II) in all microplastic treatments may indicate functional shift in soil properties; however, the measured values of the soil characteristics have not shown the significant changes (except for the bulk density values in all microplastic treatments and hydraulic conductivity together with sorptivity in HDPE treatment within the measurement at the end of GP).
Over the past few decades, food production has been sufficient. However, climate change has already affected crop yields around the world. With climate change and population growth, threats to future food production come. Among the solutions to this crisis, breeding is deemed one of the most effective ways. However, traditional phenotyping in breeding is time-consuming as it requires thousands and thousands of individuals. Mechanisms and structures of stress tolerance have a great variability. Today, bigger emphasis is placed on the selection of crops based on genotype information and this still requires phenotypic data. Their use is limited by insufficient phenotypic data, including the information on stress photosynthetic responses. The latest research seeks to bring rapid, non-destructive imaging and sensing technology to agriculture, in order to greatly accelerate the in-field measurements of phenotypes and increase the phenotypic data. This paper presents a review of the imaging and sensing technologies for the field phenotyping to describe its development in the last few years.
In recent years, there has been a growing recognition of microplastics (MPs) as significant emerging pollutants. Soil contamination by MPs, comprising plastic particles smaller than 5 mm, originates from diverse sources. The introduction of foreign substances such as MPs can instantly modify the physical properties of soil or influence soil processes, depending upon the characteristics of the plastic. The limited available studies provide evidence that insufficient attention is being paid to the impact of plastic input on soil evaporation processes. The objective of this study was to assess the impact of contamination of three types of soil (Chernozem, Umbrisol, and Luvisol) with different MPs (high-density polyethylene, polyvinyl chloride, and polystyrene) at a concentration of 5% (w/w) on the evaporative mass loss. The presence of polyvinyl chloride (PVC), high-density polyethylene (HDPE), and polystyrene (PS) significantly altered evaporative soil loss, dry bulk density, and saturated water content in different soil types. Evaporative mass loss significantly increased in Luvisol and Umbrisol soils contaminated with HDPE and in Umbrisol contaminated with PVC. In Chernozem, contamination with all examined MPs significantly reduced dry bulk density. A similar decrease in dry bulk density was observed in Luvisol and Umbrisol with PVC and HDPE. Significant reductions in saturated water content were recorded in Chernozem contaminated with HDPE, Luvisol with PS, and Umbrisol with both HDPE and PS.
The major objective of this study is to investigate changes in radish growth parameters (fresh and dry biomass and photosynthetic efficiency) and the stability of water-stable soil aggregates under contamination by different microplastic mater...