بيئة و حياتية أسماك القطان Barbus xanthopterus (Heckel)‎)‎ نهر الفرات وسط العراق

الملخص EN

Ecology and biology of Gattan Barbus xanlhopterus (Heckel) in Euphrates over, middle of Iraq have been studied through a period from September 2002 to December 2003 , water temperature ha.; been shown lowest values (14,5 ْ˚c) in January , whereas , the highest values (39˚c) was in August.

Salinity concentration and water turbidity values ranged between 0.68 to 0.81 gm/L and II to 57 NTU respectively.

Slight fluctuation in pH ranged between 7.2 to 8.1 with 7.7 mean value.

Dissolved oxygen shown highest mean values ranged between 6.9 to 11.5 rng/L in summer and winter respectively.

Variation values of gonado somatic index (GSI) recorded lowest ones in warmer months, whereas, the highest were in hot months.

On [he other hand, there is opposite relationships between liSI and relative condition a factor (Kn.) value.

The results shown that Gattan was carnivorous with dominance of animal components consisted mainly of aquatic insects’ oligoehatca and molluscs, whieh were, formed