Document Type : Research Paper

Authors

1 Civil Engineering Department, University of Kufa, Al-Najaf, Iraq

2 Environmental Research Center, University of Technology - Iraq

3 Civil Engineering Department, University of Technology - Iraq

Abstract

Within Al-Najaf lake, that is one of the important shallow lakes in Iraq, the lake facing tremendous pressure due to encroachments, discharge of untreated domestic and industrial waste, drainage water from cultivated orchards, dumping of solid waste and illegal diversion of water and currently it's still suffering from these problems and neglect. The study aimed to evaluate the eutrophication status. Eutrophication is a grave problem in lakes, a knowledge about the eutrophic state help in providing a make efficient realization of the eutrophic problem.
This study conducted to assess the Eutrophication level with a scale 0 – 100 depending on the trophic state index (TSI) and (CTSI) calculation by measuring (Chl-a), (TP), (TN) and (TSS), also measured the parameters (Tw), (Pb), (TDS), (pH), (EC), (MPN) and (COD). The least significant difference (LSD) and ANOVA analysis were performed by using the Genstat statistical program. Lake can be classified according to the Carlson index as eutrophic (CTSI > 80) most hegemony of blue-green algae, extensive macrophyte troubles. Adding, according to Trophic State Index classification (TSItotal was ranged between 88.104-89.49 depending on TP, TSS, TN, P/N and Chl-a concentrations), were classified as the lake as extremely hypereutrophic and algal scums.

Keywords

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