沉积物间隙水溶解态磷和铁(Ⅱ)高分辨同步分析方法的研究  

High-resolution and synchronous analyses of dissoloved reactive phosphorus(DRP) and dissolved ferrous iron in pore waters of sediments

作　　者：李斌[1,2] 贾飞[3,2] 张银龙[1] 孙琴[3] 许笛[2] 丁士明[2] 

机构地区：[1]南京林业大学森林资源与环境学院,江苏南京210037 [2]中国科学院南京地理与湖泊研究所,江苏南京210008 [3]河海大学环境学院,江苏南京210098

出　　处：《生态环境学报》2011年第3期485-489,共5页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(40871220、40730528);中国科学院南京地理与湖泊研究所领域前沿项目(CXNIGLAS200811)

摘　　要：沉积物具有高度的空间异质性,尤其在沉积物-水界面附近的微环境中,溶质在微小尺度上可能存在强烈的浓度梯度分布,需要借助高分辨的获取技术才能表征。本研究发展了一种沉积物微界面溶解态反应性磷(Dissolved Reactive Phosphorus,DRP)和溶解态铁(Ⅱ)的同步分析方法。利用分辨率为4 mm、平衡时间仅为2 d的微型间隙水平衡装置(Peeper装置)获取微量间隙水(～100μL·样品-1),采用384微孔板微量比色法分别测定同一间隙水样品中的DRP和溶解态铁(Ⅱ)的质量浓度,单一指标所消耗的间隙水体积由5 mL减少到仅～40μL,检出限分别为0.009和0.017 mg·L-1,精密度为1%～7%,均与常规方法相近。将该分析方法应用到太湖两个湖区的沉积物中,同步获得的微界面溶解态磷和铁(Ⅱ)的分布较好地反映了两者的关系。The distribution of solutes in pore waters in the vicinity of the water-sediment interface（SWI） may have strong concentration gradients.Observation of such heterogeneity in sediment systems depend on the resolution of measurement.This study developed a technique for high-resolution and synchronous analyses of dissolved reactive phosphorus（DRP） and ferrous iron in microenvironment near the SWI.Small volume of pore water samples for each depth（100 μL per sample） was first collected using a mini-Peeper,which has a vertical resolution of 4 mm and equilibrium time of 2 days.Concentrations of DRP and dissolved ferrous iron in each pore water sample were measured with microcolorimetric method using 384 microtiter plate.Consumption volume of each sample is about 40 μL for DRP or dissolved ferrous iron.The detection limits were 0.009 and 0.017 mg·L-1,respectively,while the detection precisions were in the range of 1%-7%.This technique was applied to the sediments in two regions of Lake Taihu,and the measured distributions of DRP and ferrous iron well reflected their relationship in microenvironment near the SWI.

关 键 词：间隙水 高分辨 溶解态磷 铁(Ⅱ) 

分 类 号：X132[环境科学与工程—环境科学]