Study on marine microplastics monitoring based on infrared spectroscopy technology

Abstract

In recent years, microplastics particles have been detected in many sea areas around the world. Microplastics has done great harm to marine and terrestrial seawater ecosystems, so it is necessary to obtain the effective statistical data of microplastics in the environment accurately and quickly for the further study of pollution in microplastics. In this paper, based on IR (Infrared Spectroscopy) technology, hyperspectral images of marine microplastics samples containing different materials were obtained. SVM (Support Vector Machine) algorithm is used to identify microplastics in hyperspectral images. The results show that the microplastics abundance ranges from 5.193 to 20.281 N/L, 6.087 to 38.679 N/L and 7.498 to 11.084 N/L, respectively, and the average abundance is 11.83 N/L, 24.84 N/L and 19.27 N/L, respectively. The types of microplastics in the bottom water of the bay in the study area are mainly fibers (53–68%) and debris (23–34%). NIR (Near Infrared) analysis shows that the characteristic curves of microplastics spectra of the same species with different particle sizes are different. IR technology combined with chemometrics algorithm has great potential for the detection of microplastics in seawater surface and seawater. This method is simple and feasible, and has the feasibility of popularization.