Environmental Chemistry•2026•DOI: 10.0000/202605-2
Surface sediment samples were collected from 28 stations in the intertidal zones of Xiangshan Harbor, Sanmen Bay, and the southern coast of Hangzhou Bay, major fishery waters in Ningbo, to assess heavy metal pollution and ecological risk. Concentrations of Cu, Pb, Zn, Cd, Cr, Hg, and As were determined. Results showed that Cu and Cr were the primary超标 factors, with mean concentrations exceeding the Class I standard (GB 18668-2002) by factors of 1.03 and 1.1, respectively, in Xiangshan Harbor; in Sanmen Bay, Cr exceeded by 1.1 times, while Cu did not. In Hangzhou Bay, Cu and Cr were elevated but below the standard. Coefficients of variation (CV) for five metals in Hangzhou Bay exceeded 30%, indicating strong external influence. In Xiangshan Harbor, As showed strong variation, and in Sanmen Bay, Hg showed strong variation. The potential ecological risk indices (RI) were 38.5, 36.7, and 31.1 for Xiangshan Harbor, Sanmen Bay, and Hangzhou Bay, respectively, all indicating low ecological risk. Spatial distribution in Hangzhou Bay revealed a decreasing gradient from a chemical industrial park, suggesting industrial discharge as a primary source. The study provides baseline data for environmental management and recommends source control and bioremediation in high-risk areas.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202511095
To address the low temporal resolution of conventional monthly dustfall monitoring and the lack of component information, this study proposed a daily dustfall measurement method that adds a filtration step to the Chinese standard method, referencing international standards. Using a sand-core filtration device with quartz or mixed cellulose ester membranes, the method achieved a spiked recovery of 101.1% ± 1.2%, good parallelism (y = 0.95x + 0.28), and satisfactory temporal closure. During autumn–winter (November 2020 to March 2021) at a representative site in Xicheng District, Beijing, daily dustfall ranged from 0.06 to 2.33 t·(km²·d)−1. Days with daily dustfall exceeding 0.7 t·(km²·d)−1 accounted for only 4% of the sampling days but contributed 25% of the total dustfall, with high values mainly occurring in January, March, and December. The insoluble fraction averaged 83% ± 12%, and a logarithmic model (y = 9.36ln(x) + 99.98) was established to estimate the insoluble proportion from insoluble dustfall (x, ≤1.00). Daily dustfall showed a strong positive correlation with average wind speed, and an exponential prediction model (y = 0.06e0.61x) was derived. Windy conditions (≥3 on the Beaufort scale) significantly amplified dustfall. The study recommends suspending earthwork, covering bare ground, and increasing watering frequency during high-wind alerts to mitigate dust pollution. This work provides a reliable method for high-resolution dustfall monitoring and insights for targeted pollution control in urban core areas.