تاثير مياه الصرف الصحي في بعض الخصائص اللمنولوجية للمياه وكثافة بعض انواع من النواعم لنھر الفرات في محافظة ذي قار/ العراق

The present study was conducted to know the effect of wastewater raised from the wastewater treatment plant in the city of Thi Qar, on the density of some Mollusca located in the Euphrates River in southern Iraq starting from September 2013until August 2014, as was the selection four stations for the study, ranged from air temperature in the study area(3.5-39)°C,either the water temperature was(6.5-37)°C,pH value was (7.2-8.6),The electrical conductivity (2329-8720) μs/cm, also salinity ranged from (4.5-17‰) and total dissolved solids (1398-5480) mg/l, dissolved oxygen (1.1-9.2)mg/l ,biological oxygen demand (0.24-5.0)mg/l, either the chloride ion was (320-1500)mg/l, sulfate (357-1098)mg/l, effective nitrates was (0.7-7.4)mg/l, and phosphate effective reaching (0.01-2.5)mg/l, The presence study recorded of ten kinds of mollusca in four selected stations in the study area, three of which belong to class Bivalvia (Uniotigridis ePseudodontopsiseuphruticus e Corbiculafluminea), and seven of them belonging to the class Gastropoda (Melanopsis nodosa Melanopsiscostata eMelanoidestuberculatae BellamyabengalensieTheodoxus jordanieLymnaea auricularia ePhysa acuta) and was the density in the first station between (85- 1269) individual/m2, the second station between (1-5) individual/m2, the third station between (9-71) individual/m2, and was in the fourth station between(64- 378) individual/m2, the study also recorded the existence of correlations between the different density of the Mollusca and environmental factors studied . study showed the presence of clear effect of the of wastewater on the physical and chemical characteristics of the river, also showed the results of statistical analysis and the presence of significant difference monthly and my locality for some of the properties studied between stations.