Present study assessed soil pollution by heavy metals and spent oil in three industrial areas of Erbil City. Soil pH ranged from 7.53±0.017 to 8.25±0.012 and EC was ranged between 103±0.882 and 465±9.955. Soils textures were loamy sand for south industry, sandy for oil selling area and north industry while loamy for control soil. The ranges of Pb, Zn and Ni were between 1.26±0.069 and 17.472±0.058; 1.439±0.006 and 3.078±0.003, and 0.399±0.061 and 0.982±0.048 ppm, respectively. The concentrations of Cd and Cr were below the detection limit and Cu levels varied from 10.307±0.334 to 0.063±0.003 ppm, whereas Cu was not detected in some sites. The highest oil residue was obtained in site 6. Oil and grease content for the groundwater samples in the studied sites were zero. Pearson’s correlation showed a significant positive correlation between Ni and moisture content and Ni and bulk density, beside to a moderate correlation between Pb and Zn. A high significant negative correlation was detected between bulk density and oil content. The lateral distribution of the heavy metals and oil residues showed higher average concentrations at the point of impact than 20 meters away. Relative Pollution Potential gave positive values for the metals and oil contents in all sites.

An experiment was conducted to assess the effect of different concentrations of the insecticide carbaryl on histological and biochemical parameters including (SOD, GSH, rGSH, CAT and MDA) on gills tissue of freshwater mussel Unio pictorum for 96 hours. Significant increase in SOD and rGSH activities was observed in a concentration- dependent manner. However, statistically significant decrease in GSH levels was observed only at highest concentration. MDA levels reached higher rate at high concentration of carbaryl treated group. Mussels show behavioral responses during exposure by exhibiting increase in duration for shell closure and increase in mucus secretion. The histopathology of gills indicated that higher doses of carbaryl resulted in massive destruction in normal architecture of gill tissue. Molluscs accumulate contaminants in their body tissues and thus are used as bio-indicator for evaluating water quality and habitat degradation.

The aquatic Heptageniidae family of Ava-sheen branch (Greater Zab Tributary) in Duhok Governorate/ Iraq was studied. Samples were collected using Surber stream sampler to study their diagnostic morphological characteristics and molecular phylogenetic profile using a nuclear gene 16s ribosomal RNA. The morphological and molecular identification supported that the three species, Epeorus longimanus, Heptagenia elegantula and Ephemerella cornutus belong to Heptageniidae family, while the molecular results also confirmed the monophyletic origin of these three genera.

Aquatic insects samples were collected from 6 sites along the Greater Zab River in the northern Iraq from Duhok and Erbil governorates over 12 months during September 2016 to August2017, which belong to seven orders (Ephemeroptera, Plecoptera, Trichoptera, Odonatan, Diptera, Coleoptera, and Megaloptera). Clustering mitochondrial DNA cytochrome c oxidase and 16S rDNA genes, morphological keys, and matches in the Barcode of Life Database, we identified 24 species return to 7 orders and 12 families, as indicated in the results. The reported species were: Ephemeroptera 5 members of the family Heptageniidae (Maccaffertium meririvulanum, Raptoheptagenia cruentata, Ecdyonurus dispar, Anepeorus rusticus, Stenonema femoratum), 1 Ephemerellidae (Seratella ignita), 1 Arthropleidae (Arthroplea bipunctata), 6 Baetidae (Baetis alpinus, Baetis braaschi, Baetis noa, Baetis harrisoni, Iswaeon anoka, Heterocloeon amplum), 1 member for each of Diptera, Coleoptera, Megaloptera and Odonatan orders, while Plecoptera 2 members Leuctridae (Leuctra hippopoides, Leuctra inermis) and Tricoptera 4 members 3 Hydropsychidae (Leptonema albovirens, Hydropsyche simulans, Arctopsyche irrorate), 1 Hydroptilidae (Ochrotrichia tenuata). Most of these recorded species and genera were mentioned for the first time and represent new records in Iraq. Presence and distribution of identified species varied between studied sites, as a result of differences in biogeographical and physical conditions.

Pollution of the environment with toxic heavy metals is spreading throughout the world with industrial progress. Various industrial, agricultural and military operations have released huge amounts of toxic heavy metals into the environment with deleterious effects on soils, water and air (Sobolev and Begonia, 2008; Zhang, et al., 2014 and Ahmad, 2014). Soil contamination by heavy metals like chromium (Cr), nickel (Ni), mercury (Hg), cadmium (Cd), lead (Pb) and cupper (Cu) are consequently the most critical environmental problems as it poses significant impacts to the human health as well as the ecosystems (Octavia, 2013; Tamiru, et al., 2014 and Owolabi and Hekeu, 2014) because they cannot be naturally degraded like organic pollutants and they accumulate in different parts of the food chain (Šmejkalová, et al., 2014). Therefore; several studies have demonstrated that microbial parameters may be useful as indicators of changing soil condition caused by chemical pollution (Oliveira and Pampulha, 2006). Microorganisms are the first