Heavy metal contaminations were assessed through a detailed soil survey in roadside soils along the Shenyang-Dalian Highway of Liaoning Province, China. Pb, Cu, Cd, Ni, and Zn were analyzed using atomic absorption spectrophotometry. The average concentrations of Pb, Cu, Cd, Ni, and Zn in roadside soils were 43.8, 26.5, 0.119, 32.1, and 71.3 mg/kg, respectively, and all concentrations exceeded the background values. Different heavy metal distribution patterns were found under different land use types. In farmland, a peak metal concentration occurred 25 m from the roadside soil, while in the forest and orchard soil all heavy metals decreased with distance from the roadside, which conformed to the exponential model. Heavy metal concentrations were markedly higher than those measured in 1999 and 2007, except for Cd. Concentrations in soils along the Shenyang-Dalian Highway were medium or low in comparison with roadside soils in other cities around the world. Overall, this assessment illustrates that heavy metal pollution in these soils is generally low, and we recommend that more attention should be given to Pb contamination in roadside soils along the Shenyang-Dalian Highway.

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This study is to investigate changes in maximum 24‐hr precipitation for 20 stations during the typhoon season (July–October) and how the El Niño–Southern Oscillation (ENSO) may modulate precipitation extremes in Taiwan. Based on the nonparametric Mann–Kendall method and Sens's test, 15 out of 20 stations (three fourth) exhibited an upward trend from 1958 to 2013. Results of the field significance test suggest that the significant increasing trend is not caused by random variability. The method of the non‐stationary generalized extreme value distribution (NGEV) is then applied to determine temporal changes in return levels. Results show that a large majority of stations are marked by an increasing trend in the three chosen return levels (2, 20, and 100 years) over the last 56 years. Therefore, more intense typhoon producing seasonal maximum 24‐hr precipitation has been observed in Taiwan. The waiting time for an extreme event to occur has shortened considerably in recent years. For stations located in western/central Taiwan, an El Niño (La Niña) event favours low (high) precipitation extremes. It is the opposite for stations in northern and eastern Taiwan. Thus, an east–west regional difference in precipitation extremes across Taiwan is noted. A NGEV model based on both time and ENSO as covariates is also applied. Inter‐annual variations influenced by ENSO are more dominant than long‐term trend in return levels for most stations in western/central Taiwan.