The Loss of biodiversity in Sawa Lake and its interpretation using different bio-assessment evidences

Sawa Lake, fish assemblage, Integrated Biological Index IBI

Abstract

This study includes ecological assessment of fish assemblage of Sawa Lake. The results were compared with studies of Shatt Al-Arab, Hor Al-Hammar, and Hor  Al- Huwayzah (Al-Saffia reserve) to clarify the status of fish assemblage environment in this area using (Evidence of species richness, Diversity, equivalence, evidence of similarity and Integrated Biological Index IBI). Six metrics were chosen to calculate the (IBI) depending on the following major categories. The first (species richness) is represented by the total number of native species, two species were obtained. The second major category covered up three metrics the first is represented by the percentage of Pinaliza abu individuals accounted for 71.4%. The second metrics enact by the percent of tolerant species which represented by 100%, while not recorded any percent of individuals that are considered as sensitive native species (metrics three). The third major category checking two metrics which is collected of percent of individuals that are considered as omnivores and carnivores which constituted 71.4% and 28.6% respectively. The results of the present study showed that the environmental assessment of Lake Sawa was weak assessment, with the value of the Integrated Biological Index 28.9 and this value is lower which compared with other results in Shatt Al-Arab, Hor Al-Hammar, and Hor  Al- Huwayzah. The values of richness index (D), diversity (H) and equivalence (J) were (0.22), (0.59) and (0.86) respectively.