Associations between microplastic pollution and land use in urban wetland sediments

Abstract

Microplastic pollution is concerning because it is widespread in aquatic environments and there is growing evidence of negative biological effects. Here, we present one of the first studies to examine microplastic pollution (plastic particles <1 mm) in urban wetlands and investigate relationships between contamination and urban land use. Sediment samples were collected from twenty independent urban wetlands, each with different types of urban land use within their catchments. Microplastics were observed at all wetlands, with an average abundance of around 46 items/kg of dry sediment. Plastic fragments were the most common type of microplastic, accounting for 68.5% of all microplastics found. Consistent with other studies, microplastic abundance was positively correlated with increased catchment urbanisation. On closer examination, plastic fragments and beads correlated with catchment urbanisation. Fragment abundance also increased in wetlands with catchments that had a higher proportion of industrial land use and decreased in catchments with higher residential densities. This study demonstrates the susceptibility of urban wetlands to microplastic pollution, further highlighting the ubiquitous nature of microplastic pollution. The prevalence of microplastic fragments indicates that plastic litter degradation is a significant source of microplastics in urban environments, especially in industrial areas.

Modeling land use impacts on spatial distribution of floating plastic litter in surface water of Southeast Asian archipelago

“…High density of HDPE in surface water is related to the population density factors as estimated by the model. The contributions of population density on plastic litter is in accordance with other results from Chesapeake Bay (Yonkos et al 2014), Great Lakes (Baldwin et al 2016), and urban wetlands (Townsend et al 2019). Combined with the anthropogenic activities, population density will contribute more in increasing plastic quantities (Best 2019).…”

A review on the occurrence, distribution, characteristics, and analysis methods of microplastic pollution in ecosystem s

“…Although it is corrosive and harmful, recycling and washing could address this issue. The experimental recovery data show that the separation effect is better than that of NaCl solution obviously [54,93,[102][103][104]. In addition, CaCl 2 solution (1.5 g/cm 3 ) is used for separation tests based on its eco-friendliness, density, and low cost [105].…”

Microplastics in Soils and Sediment: Sources, Methodologies, and Interactions with Microorganisms

“…Many fresh water sediments are contaminated with microplastics, especially in areas near plastic waste sources. Sediment samples from 20 different urban wetlands were analyzed by Townsend et al and showed a strong correlation between microplastic abundance and industrial land use (Townsend et al 2019). The study by Horton et al analyzed sediment from the tributaries of the River Thames, UK.…”