US-Egypt Cooperative Research: Study of Nutrient Fluxes via Submarine Groundwater Discharge into the Coastal Zone Around Alexandria, Egypt

该项目支持塔拉哈西佛罗里达州立大学的William Burnett博士和埃及亚历山大市海岸研究所的Ayman El-Gamal博士的合作研究。他们计划进行一项研究，研究海底地下水排入亚历山大港周围海岸带的营养通量。技术优点：海底地下水排放(SGD)是营养物质和其他溶解成分从陆地进入沿海海洋的一条重要但在很大程度上尚未量化的途径。沿海海洋学家和水文学家已经证明，淡水地下水通过沉积物缓慢而持久地渗入任何具有正水头的含水层与地表水体水力连接的地方都会发生。现在人们认识到，相当数量的海水也通过沿海含水层系统进行再循环。淡水和咸水的输入都为沿海水域提供了营养物质和其他溶解固体。该项目有三个不同的目标：(1)调查SGD在向埃及亚历山大周围沿海地区输送营养物质方面的作用；(2)利用天然放射性同位素估计地下水通量；(3)促进传播有关SGD、测量技术及其对埃及沿海管理的潜在影响的知识。选址位于亚历山大市附近的西诺巴里亚排水口附近(亚历山大市中心以西约21公里)。在亚历山大港附近的浅水深处发现了地下水。此外，由于受污染的地表水渗入含水层，地下水质量正在恶化。个人数字监测系统将使用自动测氡仪，在不同的时间段内连续测量SGD流量。他们计划为这个地点建立一个详细的营养预算。该地区营养物质的潜在来源包括地表水流入、大气沉积、跨沉积物水界面的扩散，以及目前未知的SGD。这可能是第一次对北非沿海水域的地下水排放进行研究。更广泛的影响：人力资源开发将是该项目的一个重要方面，方法是在发展中国家进行能力建设，并使研究生有意义地参与实地研究和研究的其他方面。佛罗里达州立大学的一名研究生将有机会在这个项目期间增加他的博士研究。该项目还涉及重要的海岸带管理问题，因为正在研究的城市沿海系统遭受了地下水过度消耗、与此相关的下沉以及化肥、污水和其他污染源污染增加的影响。受污染地下水的营养物质输入与近岸水域的富营养化和近海有害藻华的增加有关。该项目得到了美国-埃及联合基金计划的支持。

0809040BurnettThis project supports collaborative research by Dr. William Burnett, Florida State University, Tallahassee and Dr. Ayman El-Gamal, Coastal Research Institute, Alexandria, Egypt. They plan a study on ?Study of Nutrient Fluxes Submarine Groundwater Discharge into the Coastal Zone Around Alexandria? Technical Merit: Submarine groundwater discharge (SGD) represents an important, yet largely unquantified pathway for nutrients and other dissolved constituents from land to the coastal ocean. Coastal oceanographers and hydrologists have shown that slow yet persistent seepage of fresh groundwater through sediments occurs wherever an aquifer with a positive head is hydraulically connected to a surface water body. It is now recognized that a considerable amount of seawater is also recirculated through coastal aquifer systems. Both fresh and saline water inputs contribute nutrients and other dissolved solids to coastal waters. This project has three distinct objectives: (1) investigate the role of SGD in the delivery of nutrients to the coastal zone around Alexandria, Egypt; (2) estimate groundwater fluxes using natural radioisotopes; and (3) contribute to the dissemination of knowledge concerning SGD, measurement techniques, and its potential coastal management implications in Egypt. The selected site is located near Alexandria around the outlet of West El-Nobareya Drain (about 21 km west of the center of Alexandria). Groundwater is found at shallow depths in the vicinity of Alexandria. In addition, the groundwater quality is deteriorating as a consequence of the infiltration of contaminated surface water into the aquifers. The PIs will use automated radon monitors for continuous measurements of SGD flow over various time periods. They plan to construct a detailed nutrient budget for the site. Potential sources of nutrients to this area include surface water inflow, atmospheric deposition, diffusion across the sediment water interface, and SGD, that is currently unknown. This would likely be the first groundwater discharge study in North African coastal waters. Broader impacts: Human resource development will be an important aspect of this project via capacity building in a developing country and meaningful graduate student participation in the field studies and other aspects of the research. A graduate student at Florida State University will have the opportunity to add to his Ph.D. research during this project. The project also involves important coastal zone management issues as the urban coastal system being studied has suffered from over consumption of groundwater, subsidence relating to this over pumping, and increased contamination from fertilizer, sewage, and other pollution sources. Nutrient inputs from contaminated groundwaters have been implicated in the eutrophication of near-shore waters and the increasing occurrence of harmful algal blooms offshore. This project is being supported under the US-Egypt Joint Fund Program.