Construction and Application of On-site Rrapid Detection System for Dissolved Nickel in Seawater
Nickel is an essential element for marine organisms and may affect processes such as methane generation and nitrogen absorption in the ocean.On-site rapid determination of dissolved nickel would provide technical support for marine environmental monitoring and emergency warning.Based on adsorptive cathodic stripping voltammetry and a portable handheld electrochemical workstation,a portable on-site rapid detection system for dissolved nickel in seawater was constructed in this study to reduce the impact of changes in storage or transportation conditions on dissolved nickel concentration.After performance optimization,the detection limit of the system for nickel was 30.00 ng/L,the linear range was 0.10-100.00 μg/L,(R2=0.997),the detection time for each sample was less than 10 min.The rapid detection system had been successfully used for on-site determination in three typical aquaculture areas in the Yellow Sea,East China Sea and South China Sea.The test results showed that the dissolved nickel concentration in these three aquaculture areas met the requirements of Class Ⅰ seawater quality(≤5.00 μg/L).The concentration in the Yellow Sea and South China Sea aquaculture area was lower than that in the East China Sea.The assessment results of pollution factors showed that the three aquaculture areas were in low pollution water quality(Class Ⅰ).