Bahr El-Baqar Research Articles

Material flow analysis and integration of watersheds and drain systems: II. Integration and solution strategies with application to ammonium management in Bahr El-Baqar drain system

The objective of this paper is to develop a systematic methodology for mass integration in drain systems and watersheds. Mass integration is a holistic approach to the tracking, transformation, and allocation of species and streams. The watershed and drain system is first discretized into reaches. The MFA model developed in part I of this work (Simulation and Application to Ammonium Management in Bahr El-Baqar Drain System) is used to describe the environmental phenomena that affect the fate and transport of targeted species and the operators that characterize the system inputs and outputs as they relate to the surroundings. Next, we develop an integration framework which encompasses sources, sinks, and interception technologies to aid in the development for nitrogen-management strategies. The simulation model was transformed into a synthesis model by introducing optimization variables and including models for the potential management strategies. The problem of minimizing negative environmental impact subject to technical, social, economic, and regulatory constraints was posed as a nonlinear optimization program whose solution identified and synthesized the most effective solution strategies. These mathematical models and management strategies were coded into a computer-aided tool using LINGO programming platform. The program can be readily modified to address a variety of cases. Tradeoffs and sensitivity analysis were established using the devised model. The devised framework was applied to an Egyptian drain system (Bahr El-Baqar) along with the outfall to Lake Manzala. The results of the case study provide solution strategies for nitrogen management along with their technical, economic, and environmental implications.

ECOLOGICAL STUDIES ON NITROGEN CYCLE BACTERIA IN LAKE MANZALA, EGYPT

Six stations were chosen to represent the different micro-habitats along the southern part of Lake Manzala. In addition, two main drains, Bahr El-Baqar and Hadous were represented. Water and Bottom sediments were collected through four successive seasons (Autumn 1999 - Summer 2000) for physico-chemical and bacteriological analyses. The results showed that water temperature recorded the lowest value during Winter, while it recorded the highest during Summer with an annual amplitude 14.8°C. The Lake is shallow with a depth ranging from 0.85 - L31 m. The pH values were in the alkaline side. The water transparency fluctuated from 19.5 - 325 cm . The organic matter and organic carbon ranged from 5.28 - 8.71% and 3.06 - 5.06%, respectively. Bacteriological analysis showed that the highest counts of the studied bacteria were recorded in Bahr El-Baqar and Hadous Drains compared with Lake Manzala' stations.Conversly , the lowest counts of nitrifying bacteria were recorded in Bahr ElBaqar Drain and its discharge points.

Metal pollution loading, Manzalah lagoon, Nile delta, Egypt: Implications for aquaculture

High cultural enrichment factors are found for Hg (13×), Pb (22.1×), and other potentially toxic metals (e.g., Sn, Zn, Cu, Ag) in the upper 20 cm of sediment cores from the southeastern Ginka subbasin of Manzalah lagoon, Nile delta, Egypt. Cores from other areas of the lagoon show little metal loading. Metal loading followed the closure of the Aswan High Dam, the availability of abundant cheap electricity, and the development of major power-based industries. Industrial wastes containing potentially toxic metals are dumped into the Nile delta drain system. The load carried by Bahr El-Baqar drain discharges into the Ginka subbasin, which acts as a sink and results in metal loading of the sediment deposited there. Further development of aquaculture in this subbasin, of food-stuff agriculture on recently reclaimed lagoon bottom, or where irrigation waters come from Bahr El-Baqar drain or its discharge should be halted or strictly limited until potentially toxic metals in the drain waters and sediment are removed and polluted input drastically reduced. This environmental assessment of heavy metals in aquaculture or agriculture development should extend to other waterbodies in the northern Nile delta, particularly Idku lagoon and lake Mariut, where industrial metal-bearing wastes discharge into the waterbodies.