بعض الجوانب البيئية و الحياتية للكارب البروسي Carassius auratus gibelio في سد البدعه ذي قار-العراق

Abstract EN

Sixity five specimens of Prussian carp (Carassius auratus gibelio) were Collected from Al-Baddah Dam for the period from January to March 2008.

Monthly changes in physical and chemical properties of water were investigated.

Abiotic characters, namely air and water temperatures, transparency, salinity, dissolved oxygen, carbon dioxide, pH, total alkalinity, total hardness, nitrite, nitrate and phosphate were measured on regular basis for six months.

Measurements for captured fish included total length, total weight, cleaned weight, and gonad weight.

Age was also determined.

Air temperature ranged from 14o C in January and 16o C in June.

Water temperature ranged from 12 oC in January and 35o C in June.

light penetration ranged between 40-65 cm.

The lowest values of salinity (1.53 ppt) were encountered in May, and the highest values ( 4.99 ppt) were in February.

Dissolved oxygen showed a decline during the warm months (June), amounting to 8 mg/L.

pH ranged between 6.7 and 7.8.

Carbon dioxide values were fluctuating and was totally absent in January,the highest values were recorded in may,June (4 mg/L).

Total alkalinity exhibited lower values (140 mg / L) in February, while the highest in May (150 mg / L).

Total hardness showed the lowest concentrations in January (180 mg / L) and highest in June (360 mg / L).

Nitrate ((NO3) showed remarkable rise in May (58.13 µg _ atom N / liter), and the lowest (24.76 µg _ atom N / L in April.

Nitrite ((NO2) Scored highest values (0.12 µg _ atom N / l ) in April and the lowest (0.03 µg _ atom N / l) was in January.

Concentrations of phosphate characterized by gradual increase during March and April , to achieve its peak in May (5.11 µg _ atom phosphorus / L) and the lowest was in February ( 0.62 µg - atom N / liter.It notes that there is increasing in length in the previous years .

Four groups of age were registed .

The third age group were higher length (25.7cm) and there is growth in the carp fish in the total weight .

It abserved that there is parallel in the increasing in weight with the age development .

The higher weight was (209.46) and (220.46) in the second group .

there was a extrusive relationship between the length of fish weight .