Abstract
Lakes are the most fertile , productive and interactive ecosystems in the world . Quaid – e –Azam Park is gifted with lake. It is located in Steel Town, coordinates: 24°51´41˝N, 67°19´54˝E. The present study was designed to determine the monthly variation in physico-chemical parameters and zooplankton population dynamics at Quaid – e – Azam park Lake for a period of six months from April to September, 2011. Water samples were collected on monthly basis and were analyzed for estimation of water colour, pH, Dissolved Oxygen, Acidity, Sulphate and Phosphate contents. The significant monthly variations were found in all the parameters under study. The zooplankton groups found in the lake were in the order Copepoda > Ostracoda > Cladocera > Rotifera.
