Environmental study of the zooplankton in southern Iraqi marshes.

Abstract

The present study has been carried out during the period from September 2003 till August 2004. Samples of zooplankton, which include copepoda, cladocera, ostracoda, rotifera, nauplii and shrimp larvae, were collected bimonthly from Al-Chabaish, Al-Hammar and Al-Fuhud marshes located inside boarder of Al-Chabaish quarter in Thi Qur governorate. The highest zooplankton density (229.86 Ind./L., 103.58 Ind./L.) were found during October in Al-Chabaish and Al-Hammar marshes and 425.45 Ind./L. during March in Al-Fuhud marsh. The low density (47.86, 5.15, 25.1 Ind./L.) were observed during September, May and July for Al-Chabaish, Al-Hammar and Al-Fuhud marshes, respectively. The influence of some environment factors on the zooplankton abundance were investigated. The highest water level in Al-Hammar and Al-fuhud was noticed in April 2004; however, the new releasing water reached Al-Chabaish in February 2004. The results of the current study show negative relationship between zooplankton density and each of water temperature, depth, dissolved oxygen and biological oxygen, and positive relationship with pH in Al-Chabaish marsh. In Al-Hammar marsh the relationship was negative between zooplankton density and each of depth, dissolved oxygen, and positive with water temperature and biological oxygen demand. In Al-Fuhud marsh, negative relationship was found between zooplankton density and biological oxygen demand and positive with dissolved oxygen and depth.