Mesopotamian Journal of Marine Science

Fish samples were taken from both Red Sea-coast of Yemen and the North-West Region of the Arabian Gulf for determination of Polycyclic Aromatic Hydrocarbons (PAHs) using capillary gas chromatography. The study revealed measurable levels of PAHs in muscles of edible fishes collected from both areas. The source of PAHs is mainly petrogenic originating from oil spillage, refinery effluents, and/or heavy ship traffic. This study indicates that the accumulation of PAHs in the collected fish samples was very low, and it may not represent a serious hazard on human health at present, however, long term exposure via diet may impose certain undesirable health consequences. These concentrations are within the range of PAHs values reported for other comparable regional samples.

A total of thirty samples were collected from Khor Abdullah supratidal clastic sediments NW Arabian Gulf. These samples were firstly air dried, then clay fraction separated and the prepared oriented clay samples were X-rayed, the obtained diffractograms revealed the occurrences of the kaoilinite, palygorskite, chlorite, montmorillonite, montmorillinte-chlorite, illite, and montmorillonite-illite clay minerals . The textural analyses showed that the sediments investigated are siltyclay and clayeysilt in nature, the mechanical analysis illustrates that Khor Abdullah supratidal sediments are fine to very fine, poorly sorted deposited in quite aquatic environments which emphasized that the studied sediments were deposited in low energy environment. Heavy mineral analyses proved that Khor Abdullah sediments mostly derived from igneous, with subordinate amount of metamorphic and ancient sedimentary rocks, such diverse trend of rocks cropping out at north and northeastern parts of Iraqi terrain, and southeast Turkey, i.e. at the catchments area of Tigris and Euphrates Rivers and their tributaries.

The intent of present study was to examine the toxicity, uptake, and depuration of oil–water mixtures from Nahran–Umar crude oil of two types, water soluble fractions (WSF) and oil-in-water dispersions (OWD). The test organisms used in these experiments were the shrimps, Caridina babaulti basrensis and Atyaephyra desmaresti mesopotamica, presence in Shatt Al– Arab river. In the toxicity test experiments, the two species of shrimps were subjected in river water to different concentrations of WSF and OWD using renewal toxicity system for 24 and 48 hours under laboratory conditions. In the median lethal concentration (LC50) parameter, The shrimp C. babaulti basrensis was more sensitive to oil-water mixtures than the shrimp A. desmaresti mesopotamica. The WSF was slightly more toxic to shrimps than the OWD. In the uptake and depuration experiments, we exposed the shrimp, C. babaulti basrensis to 2 ml of WSF/l of river water for 24 hours. Exposure water and organisms were sampled periodically for the total hydrocarbons concentration. Hydrocarbons levels in the exposure solution decreased rapidly while concentration in the shrimp tissue increased dramatically. After 6 hours, tissue levels of hydrocarbons were 150 times grater than water levels. Depuration of hydrocarbons was rapid and began during the exposure period, complete depuration did not occur.

Geotechnical properties of many boreholes were collected and interpreted for identifying the bearing strata in Basrah region. Based on these geotechnical properties, the lithological succession along the Shatt Al-Arab River from Al-Qurna to Al-Fao in Basrah Region, could be classified into eight layers. The bearing capacity of surface layer is 300-600 kN/m2, which is suitable for small construction projects, whereas, the deepest eighth layer has N-value >50, this is suitable for large construction projects. The other sixth layers in between are very weak and of low plasticity, where the N-value is <15, which are not suitable for any construction projects. The lateral distribution of the layers explain the source and the geological history of the area.

The turbidity of Al-Eiz river water has been removed in a pilot plant designed and constructed locally. The local lime, ferrous sulfate and polymer have been used as coagulants and the last as a coagulant aid with ferrous sulfate for different levels of turbidity. Chemical pretreatment of the river water was first investigated on a laboratory scale to optimize the coagulation and flocculation conditions with respect to the turbidity, and zeta charge indexes after sedimentation and filtration processes. Experimental investigations have been carried out in a pilot plant to determine the optimum dosages of coagulation and coagulation aid required to reach the permissible limits of turbidity. The results were discussed and compared with the worldwide standards where a good agreement has been observed.

This study explicates the efficacy of the Iraqi marine-fishing means in providing fishes as foodstuff. It covers a period of time ranging from 1990 to 2004 and surveys the territorial waters of Iraq north to the Arab Gulf. Also, it stresses the significance of such efficacy since it plays a double role; first as an economic factor contributing into offering work chances in labour market, and second as a means of food provision. Moreover, the study reveals that there are many factors, which positively affect this particular efficacy in question some of which are natural, some human. In addition, the study notices that the governmental default in aiding this economic activity only leads to make it mainly thrown into the grip of the private sector. Also, the study shows the ups and downs of this activity throughout the period in question. It may be noticed that the Iraqi marine fishing in means does not differ from what is practiced in the Arab Gulf Basin in respect to the kinds of ships, boats ….etc or means adopted in fishing. Hence, the study brings into the for the increased numbers of these means which the local ship industry provides in order to guarantee future increase expectations. However, the study reveals that large amounts of fishes were sold out at sea by the very fishermen only to avail themselves of currency differences. The study recommends that (1) the state interference with and support to this sector are fundamental to its growth and development and (2) the foundation of a port (for these ships and boats) special to fishing is a fundamental support not only to this activity but also to the provision of extra work chances in labour marker.

The effect of Electrofishing on important fish species in the marshes had been stydied. It was found that these fishes showed many kind of harmless injuries related to electrofishing. Such as Hemorrhages of gills and mussles, as well as many kind of spinal injuries. The studied species were differing in the injuries percentage. Liza abu showed no injuries. The spinal injuries include Compretion of vertebrae, spinal misslignment and Vertebrae fracture. The percent and level of injuries were differing according to species and size. Portable X-ray device was used and it gives good result in studying spinal injuries.

The effect spatial and temporal changes of benthic invertebrate's composition were studied in two selected sites, before and after north part of Main Drainage Channel meeting within drainage canals of Abu-Grabe, Al-Rhedwania and Al-Yosfiaa. Monthly samples were collected from September 2001 to August 2002. Water temperature ranged between 10 in January to 29.5 C in August. Salinity concentration and water turbidity recorded lowest mean values (3.4 gm/l and 8.8 NTU respectively) in the first site, whereas, highest values was (6.2 gm/l and 30.0 NTU respectively) in the second site. Dissolved Oxygen has been shown highest mean values reached 7.3 mg/l in the first site; while, the lowest was recorded in the second site reached 3.9 mg/l. The present study classified 33 species of benthic invertebrates, aquatic insect larvae, oligochaetes and molluscs formed 18, 11 and 6 species, respectively, as well as one genus only of crustacean. Three benthic invertebrate species were found to be dominate, namely Chironomous sp. (Chironomidae), Pristina aequiseta (Naididae) and Cypris sp. (Ostracoda). A total invertebrates density were recorded lowest values (4110.7 indi/m2) and highest ones (4906.6 indo/m2) in the first and second sites respectively. The highest values of total invertebrates density represented by oligochaetes and crustacean (3979.1 and 590.8 indi/m2 respectively) in the second site. A total biodiversity values in the Main Drain Channel reached 1.8 and 2.6 in the first and second sites respectively. The present study showed increasing in total density and biodiversity of benthic invertebrates in the second site of the north part of Main Drainage Channel after meeting within drainage canals of Abu- Grabe, Al-Rhedwania and Al-Yosfiaa.

A study of bases on the density and the biomass of six species of crustacean from the intertidal and sub-tidal region of Shatt Al-Arab were achieved in the period from July 1997 to May 1998. These are Atyaephyra desmaresti mesopotamica, Al-Adhub 1987, Elamenopsis Kampi, Calman, the crab Sesarma boulengeri, the amphipoda parhyala basransis, Salman, isopoda Spharoma annandalei annandalei, Annina mesopodamica ,the density recorded for the mentioned species are ranged as follow: 8-128, 4-242, 0-300, 262-682, 35-515 and 211-230 ind./m2 respectively. While the biomass recorded are ranged as follow: 0.14-1.18, 0.01-1.49, 0-13.2, 0.05-0.02, 1-1.78 and 0.91-4.2 gm/m2 respectively. We were compared our result with previous records which have been done by various authors during the (1980-2000). It was noticed that there were a decline in densities of the crustaceans and some of them were totally absent for certain period of time, these indicated considerable change that had occurred in the environment of Shatt Al-Arab.