Movement of Microplastics in soil-plant-atmospheric continuum

Abstract

The aim of this study is to improve our understanding regarding Microplastics. Microplastics are one of the most significantly emerging contaminants with their increasing occurrence in environment. It now has become of utmost important to study about their behavior and interactions with soil-plant system along with other organic and inorganic materials. While there has been a significant rise in research activities relating to microplastics in the last decade, we still don’t know much about microplastics fate and transport in terrestrial ecosystem. Progress in research on microplastics in soil is hampered by inherent technological discrepancies and difficulties in analyzing particles in complex matrices, and studies on the diversity and trends of microplastics in soil environments are urgently required. Limited evidence has shown that the confluence and engagement of microplastics with pollutants they absorb may have an impact on soil health and its function, as along with its migration to the food chain. So we can say that there are significant research gaps in the quantification of microplastics in soil, factors influencing microplastic concentrations, and microplastic masquerading as soil carbon storage, all of which require additional effort. This study also aims to develop our understanding on analyzing the effect of MPs on phytoremediation. The study employs the plant Canna Indica which is known for its phytoremediation properties of heavy metal contaminants. A modelling framework is developed to simulate the uptake mechanism of MPs by plants in different soil profiles. Soil moisture flow and contaminant transport equations are solved numerically using HYDRUS 1-D for predicting soil moisture regimes and MP concentration gradient in vadose zone. Further, mass balance is performed for each case to quantify the MP stored in soil. Results of this study can be used for managing MP polluted soil-water resources.