Li Hui, Lu Jun, Li Qu-Sheng, He Bao-Yan, Mei Xiu-Qin, Yu Dan-Ping, Xu Zhi-Min, Guo Shi-Hong, Chen Hui-Jun
School of Environment, Jinan University, Guangzhou, 510632, China.
Key Laboratory of Water/Soil Toxic Pollutants Control and Bioremediation, Department of Education of Guangdong Province, Guangzhou, 510632, China.
Environ Geochem Health. 2016 Feb;38(1):99-110. doi: 10.1007/s10653-015-9688-x. Epub 2015 Mar 7.
Leaching experiments were conducted to investigate the effects of desalination levels and sediment depths on potential bioavailability of heavy metal (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in tidal flat soils. The data showed that both the desalination levels (p < 0.001) and soil depths (p < 0.001) had significant effects on the concentrations of acid-volatile sulfide (AVS). AVS concentrations generally exhibited increasing trends with an increase in depth and decreasing trends with enhanced desalination levels. The desalination levels had significant (p < 0.05) effects on the concentrations of simultaneously extracted metal (SEM; Cd, Cr, Cu, Fe, Mn, Pb, and Zn). Moreover, the concentrations of SEM (Cd, Cr, Cu, Fe, Mn, Pb, and Zn) generally tended to decrease with an increase in the desalination level. The desalination treatment significantly reduced the ratios of SEM/AVS compared with control. However, the ratios of SEM/AVS increased with enhanced desalination levels in treatments. Results reveal that low desalination treatment is better for reducing toxicity to benthic organisms than high desalination treatment. Since these reclaimed tidal flats with low desalinisation are suitable for saline water aquaculture, transforming the present land use of reclaimed tidal flats from fresh water aquaculture into saline water aquaculture may reduce health risk of heavy metals remained in sediments. These results will also contribute to our understanding of the dynamic behavior of heavy metals in the reclamation of tidal flats during leaching and the role of the ratio of SEM/AVS predictions on assessing the ecological risks of reclaimed tidal flats.
进行了淋溶实验，以研究脱盐水平和沉积物深度对潮滩土壤中重金属（镉、铬、铜、铁、锰、镍、铅和锌）潜在生物有效性的影响。数据表明，脱盐水平（p < 0.001）和土壤深度（p < 0.001）对酸挥发性硫化物（AVS）的浓度均有显著影响。AVS浓度通常随深度增加呈上升趋势，随脱盐水平提高呈下降趋势。脱盐水平对同步提取金属（SEM；镉、铬、铜、铁、锰、铅和锌）的浓度有显著（p < 0.05）影响。此外，SEM（镉、铬、铜、铁、锰、铅和锌）的浓度通常随脱盐水平的提高而趋于降低。与对照相比，脱盐处理显著降低了SEM/AVS的比值。然而，在处理中，SEM/AVS的比值随脱盐水平的提高而增加。结果表明，低脱盐处理比高脱盐处理对降低底栖生物的毒性更好。由于这些低脱盐的围垦潮滩适合进行咸水养殖，将围垦潮滩目前的淡水养殖土地用途转变为咸水养殖可能会降低沉积物中残留重金属的健康风险。这些结果也将有助于我们理解潮滩围垦过程中淋溶期间重金属的动态行为以及SEM/AVS比值预测在评估围垦潮滩生态风险中的作用。
