Jurujuba Cove pore water and sediment Data - Rio de Janeiro - Brazil

The Jurujuba Sound is located within Guanabara Bay (Rio de Janeiro - Brazil), this overpopulated region probably may have contributed to the accumulation of chemical compounds in the sediments by diffuse sources (the Cachoeira and Icaraí rivers). Jurujuba Sound also supports a considerable area of mussel farms. In this research two main investigation approaches had been chosen, pore water and sediments nutrients. This work aims to indicate the characteristic distribution of the superficial sediment (pH, Eh, particular size, carbonate, organic matter and phosphorus, and nutrients present in pore-water (C, N, P) along Jurujuba Sound area. The pH and Eh were measured in-situ using a Hanna Multiparameter probe. In the laboratory, nutrients in pore-ware water were measured by the colorimetric method with a KASUAKI UV / VIS spectrometer at different wavelengths for phosphate (and total phosphorous) (880 nm), nitrate (505 nm), nitrite (540 nm), and ammonium (630 nm). The grain size analysis was determined on a laser analyzer, carbonate was performed by mass difference. Spatial distribution maps were produced for each parameter, to assess nutrients spatial behavior and their relationships with other parameters. The results demonstrate high N and P concentrations in pore water, indicating the possible release of the relevant nutrient amount in the water column. The high rate of domestic effluent input (Confirmed by TOC/TN ratio) led to high nutrient levels in sediments and porewater, potential release from the bottom sea could cause fish mortality events and other toxic effects.儒茹茹巴水道（Jurujuba Sound）位于巴西里约热内卢的瓜纳巴拉湾（Guanabara Bay）内，该区域人口稠密，可能通过面源污染（卡绍埃拉河与伊卡拉伊河）导致沉积物中化学物质累积。儒茹茹巴水道同时分布有大面积贻贝养殖场。 本研究选取了两种主要研究方向：孔隙水与沉积物营养盐分析。本研究旨在阐明儒茹茹巴水道沿岸表层沉积物的特征分布（包括pH、氧化还原电位（Eh）、粒径、碳酸盐含量、有机质与磷），以及孔隙水中的营养盐（碳、氮、磷）分布特征。 pH与氧化还原电位采用Hanna多参数探针（Hanna Multiparameter probe）原位测定。实验室阶段，孔隙水营养盐通过比色法测定，使用KASUAKI紫外-可见分光光度计（KASUAKI UV / VIS spectrometer），针对不同指标选用对应检测波长：磷酸盐（及总磷）为880 nm、硝酸盐为505 nm、亚硝酸盐为540 nm、铵盐为630 nm。沉积物粒径分析采用激光粒度仪完成，碳酸盐含量通过质量差减法测定。 研究人员为各参数绘制了空间分布图，以评估营养盐的空间分布特征及其与其他参数的相关性。 研究结果显示，孔隙水中氮、磷浓度较高，表明有大量营养盐可能向上覆水层释放。生活污水的高输入量（由总有机碳/总氮（TOC/TN）比值证实）导致沉积物与孔隙水中营养盐含量偏高，若这些营养盐从海底潜在释放，可能引发鱼类死亡事件及其他毒性效应。