暴雨型湿地孔隙水中铁锰的时空变化特征

为了进一步探究湿地的净化机制和生物地球化学循环过程,2004～2006年通过连续3 a对武汉动物园暴雨型人工湿地进行原位定期监测,主要研究了湿地孔隙水中铁锰的时空分布特征及其对氧化还原电位(oxidation reduction potential,ORP)的影响.结果表明,暴雨型湿地水位出现周期性的波动,水位的变化范...

Spatial and Temporal Variation of Fe and Mn in the Stormwater Wetland

To study the purification mechanism and biogeochemical cycle of wetlands, the concentration of Fe/Mn and oxidation reduction potential (ORP) in the pore water were monitored in situ on the Wuhan Zoo stormwater wetland from 2004 to 2006. The results showed that the water level of the wetland was changed from -10 cm to 30 cm, and the range of ORP was-120-220 mV. The elements of sulfur, iron and manganese were the main oxidation and reduction systems in the wetland. The ranges of total Fe, Mn and Fe2+ concentration were 0.60-2.35, 0.75-1.89 and 0.20-1.25 mg x L(-1), respectively. The concentrations of total Fe, Mn and Fe2+ were higher in spring and summer than that in autumn and winter, while the sulfate concentration was on the contrary and the ratio of Fe2+/Fe was slightly various in different seasons. From the surface of 10 cm to 50 cm underground, ORP and pH was decreased, whereas the concentrations of total Fe, Mn and Fe2+ were increased (except for the surface water). Through the correlation analysis, it was showed that the correlation of ORP and total Mn and Fe2+ was negative and significant, while there was no significant correlation between ORP and total Fe (R = -0.169, p < 0.0001). The order of the correlation coefficient was total Mn, Fe and Fe2+ in turn. Therefore, the systems of sulfur, iron and manganese were the important component of the oxidation and reduction system for stormwater wetland.