State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-Environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; Dongtinghu Lake Ecological Observation and Research Station (DEORS), Yueyang, Hunan Province, 41400, PR China; Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Kunming, Yunnan Province, 650034, PR China.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-Environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; Dongtinghu Lake Ecological Observation and Research Station (DEORS), Yueyang, Hunan Province, 41400, PR China; Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Kunming, Yunnan Province, 650034, PR China.
J Hazard Mater. 2017 Jun 5;331:36-44. doi: 10.1016/j.jhazmat.2017.02.024. Epub 2017 Feb 21.
Diffusive gradients in thin films (DGT) technique has been newly designed for the identification of formation mechanisms of "internal phosphorus (P)-loading" and the numerical simulation of P exchange at DGT/sediment interface in Lake Dianchi. The primary mechanism was Fe-redox controlled P release from Fe-bound P in sediments, which was revealed by C (P and Fe), total P (Fe) and P (Fe) fractions in NHCl and BD phases in sediments and their relationships at sites (N-T). The breakdown of algae biomass in the top layer of sediments at sites (O-T) and the coupled P/Fe/sulfur reactions at two depths at site N played a minor role in P release. The "internal P-loading" was calculated to be 19.23ta, which was 3.0% of the "entering P-loading". At sites (1-9), DGT induced flux in sediments (DIFS) model for P was used to derive curves (i) the resupply parameter (R) against deployment time and (ii) the dissolved/sorbed concentrations against the distance at DGT/sediment interface, the variation characters of which were controlled by kinetics and sediment-P pool. Sulfide microniches in sediments related to P release were evaluated by computer imaging densitometry (CID). DGT-DIFS-CID should be a reliable method to reveal P mobilization in lake sediments.
扩散梯度薄膜（DGT）技术是为了识别“内部磷（P）加载”的形成机制以及滇池 DGT/沉积物界面处 P 交换的数值模拟而新设计的。主要机制是 Fe 还原控制 P 从沉积物中 Fe 结合的 P 中释放，这是通过沉积物中 NHCl 和 BD 相中 C（P 和 Fe）、总 P（Fe）和 P（Fe）分数及其在站点（N-T）的关系揭示的。沉积物顶层藻类生物量的分解（O-T 站点）以及 N 站点两个深度处的 P/Fe/硫反应耦合在 P 释放中作用较小。“内部 P 加载”被计算为 19.23ta，占“进入 P 加载”的 3.0%。在站点（1-9），用于推导 P 的 DGT 诱导沉积物通量（DIFS）模型的曲线（i）补给参数（R）与部署时间的关系和（ii）DGT/沉积物界面处溶解/吸附浓度与距离的关系，其变化特征受动力学和沉积物-P 库控制。通过计算机成像密度计量法（CID）评估与 P 释放相关的沉积物中硫的微观环境。DGT-DIFS-CID 应该是一种可靠的方法，可以揭示湖泊沉积物中的 P 迁移。
