BIODIVERSITY OF BENTHIC MACROINVERTEBRATES IN Al-RAZZAZA LAKE AT KARBALA PROVINCE/ IRAQ

This study was conducted to assess the biodiversity of benthic macroinvertebrates with assessing the water quality of Al-Razzaza Lake by chemical and physical analysis in addition to The Shannon – Wiener biological diversity index. The samples were collected each month from January 2013 to March 2014, from three sits. The chemical and physical analysis includes: water temperature (15 – 31) 0C, DO (4.05 – 7.3) mg/l, salinity (1.98 – 2.52) ppt., TSS (4748 – 8157) mg/l, pH (5.11 – 8.7) & organic matter in sediment (1.8 – 13.6) %. Arthropods recorded in the present study were Crustacea and Hexapoda (Insects). Crustacea were including Decapoda Metapenaeus spp. (shrimp); Amphipoda Gammarus spp. (scud) and Balanus amphitrite (sessile genera). Insects consist of two genera including: Midge larvae and Damselfly Nymph. Mollusca that found during the study period were consisting of ten genera, including seven genera of gastropods and the remaining three genera are bivalves. Gastropods are Melanopsis costata; Melanoides tuberculata; Cerithidea cingulata; Theodoxus jordani; Hydrobia ventrosa (first time record in Iraq); Lymnaea auricularia and Physa acuta. Bivalves are Laevicardium flavum; Corbicula fluminea and Unio tigridis. The Shannon – Wiener biological diversity index revealed a value of diversity between 1.22 in winter 2014 to value of 1.95 in autumn.