Assessment of some water quality characteristics as guide lines for the management of pond fish culture in Lake Manzala, Egypt

Abstract

The Optimum fish production is totally dependent on the physical, chemical and biological qualities of water to most of the extent. Hence, successful pond management requires an understanding of water quality. Water quality is determined by variables like temperature, transparency, turbidity, water colour, carbon dioxide, pH, alkalinity, hardness, unionised ammonia, nitrite, nitrate, primary productivity, The obtained results declared that, the agricultural and domestic sewage drained into the lake from urban and rural lands have an adverse effects of water quality characteristics of the lake. Nowadays, there are huge amount of treated sewage from Bahr El-Baqr drain discharged into the lake, but the water quality still undergoes a severe deterioration. The most studied parameters; especially nutrient salts and toxic gases varied in wide range, increased in the southern region and decreased towards north eastern part of the lake. This study demonstrates the usefulness of multivariate statistical approaches for analysis and interpretation of water quality data, identification of pollution sources and understanding of temporal variations in water quality for effective lake water quality management