Understanding phosphorus fractions and influential factors on urban road deposited sediments

Yushan Chen; Zilin Yang; Jiawei Dong; Nian Hong; Qian Tan

doi:10.1016/j.scitotenv.2024.170624

Understanding phosphorus fractions and influential factors on urban road deposited sediments

Sci Total Environ. 2024 Apr 15:921:170624. doi: 10.1016/j.scitotenv.2024.170624. Epub 2024 Feb 5.

Authors

Yushan Chen¹, Zilin Yang¹, Jiawei Dong¹, Nian Hong², Qian Tan³

Affiliations

¹ Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China.
² Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China.
³ Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China. Electronic address: qian_tan@gdut.edu.cn.

PMID: 38325458
DOI: 10.1016/j.scitotenv.2024.170624

Abstract

Phosphorus (P) is a primary pollutant that builds-up on urban road surfaces. Understanding the fraction and load characteristics of P, as well as their relationship with urban factors, is helpful for assessing the ecological risk of urban receiving water bodies. This study presents the characteristics of build-up loads of P fractions in road-deposited sediments (RDS) in Guangzhou, China, analyzes their correlation with three urban factors (road, traffic, and land-use area), and then estimates the exceedance probability of P in stormwater runoff over the past 10 years. The results showed that detrital apatite phosphorus (De-P) performed the highest build-up load on urban road surfaces, followed by apatite phosphorus (Ca-P), iron-bound phosphorus (Fe-P), exchangeable phosphorus (Ex-P), aluminum-bound phosphorus (Al-P), organophosphorus (POP), dissolved inorganic phosphorus (DIP), occluded phosphorus (Oc-P), and dissolved organic phosphorus (DOP). Depression depth, road materials, and land-use fractions affected the P fractions. The P in the RDS may have originated from three distinct sources: road background, domestic waste, and untreated wastewater discharge. In the most recent 10 years, the event mean concentrations of total P in the RDS have had a 30 % probability of exceeding 0.4 mg L^-1, which indicates a serious threat of P to receiving water bodies. The outcomes of this study are expected to provide valuable guidance for elucidating the principal categories of urban non-point source P pollution and enhancing the ecological health of urban water environments.

Keywords: Event mean concentration; Phosphorus fraction; Road-deposited sediments; Urban factors; Urban non-point source pollution.