Mesopotamian Journal of Marine Science

Sawa Lake is located in the southwest of Samawa city, it is of geological significance because it lies in the transitional zone between the sedimentary plain and the western plain, which is semi-desert and relies on the ground water as providing sources. It has a special case in sedimentation. The mineralogical composition of the lake sediments is characterized by Gypsum Calcite, Anhydrite, and Hematite, which is in turn builds different forms of sedimentary structures, including the tuberous, concretion, Nodule, and linear forms, as well as the deposition of calcium carbonate at the bottom of the lake in general. The cones were deposited by Chara algae (biological deposition), which collect sand grains from the atmosphere and connect them with calcium carbonate, these structures in the southern part of the lake are close to the sand dunes. The physical deposition in the lake was based mainly on wind and dust storms and the presence of sand dunes in the south and south-west and some areas in the north-west of the lake. The results of the grain size analyses showed the dominance of sand, more than 80%, and the silt does not exceed 20% while the clay is 1%. The north and south east of the lake, which is far from the movement of sand dunes does not exceed 70%, while the silt reaches 30% and the clay is still about 1%. This process detects the effect of sand dunes movement in the area.

The characteristics of the tidal wave propagates along Khor Abdullah and Khor Al-Zubair were studied based on comprehensive field measurements of water level at three locations by using harmonic tidal model. The results revealed that there is a gradual increase in the amplitude of tidal wave when it propagates towards an inland direction due to the convergence nature of the study area. Also, the results of harmonic analysis led to estimate 28 tidal constituents that contribute to water level fluctuations, and M2 was the main contributor, followed by K1, S2, O1, and N2, and the astronomical tide is responsible for about 96% of these variations. The ratio between the amplitudes of the principle diurnal to the principle semi-diurnal constituents gave the tide a form number of 0.68, 0.48 and 0.44 in Khor Abdullah, Umm Qasar and Khor Al-Zubair port stations, respectively. Hence the tide is characterized by mixed, predominantly semi-diurnal. Based on the tidal wave deformation due to the nonlinear tidal interactions, the study area is classified as a flood dominant which suffers from a continuous deterioration in their depths. The results provide useful information for understanding the general behavior of tidal wave and will be significant in the future assessments of coastal developments in this region

The annual O2 consumption, annual energy budget and the ecological efficiencies of a population of the barnacle Balanus amphitrite amphitrite were estimated in Garmat-Ali river, in the period October 1994-September 1995. The annual O2 consumption was 2156 kJ/ m2/yr, the rate of O2 consumption increased with increasing temperature and body weight, the barnacle consumes oxygen at a rate of 0.622 µlO2/mg/h at 15°C, 0.84 µlO2/mg/h at 23°C and 0.954 µlO2/mg/h at 30°C. The Q10 values increased with increasing size of barnacle. The food items provided were the alga, Chlorella sp. with a calorific contents of 3.2 kcal/g DW, and a flesh of the clam C. fluminea with 5.4 kcal/g DW. The barnacle assimilates the flesh of the clam about 7 times more than assimilating the Chlorella. The barnacle allocates 45-55% of the assimilated energy for net growth and 27-37% for metabolic energy expenditure, whereas 18% is channeled for faeces production. The respiratory coefficient (R/P) of this barnacle was 0.6. The assimilation efficiency for the plant and animal food were 88-91%. The annual energy budget equation for a population of barnacle at Garmat-Ali river is: Cp 16271.14 = Pp 11639.55 + Rp 2156 + Fp 2475.60.

This study aims to apply Artificial Neural Network (ANN) to map the groundwater contamination of the Dammam aquifer by heavy oil in the middle of Iraq. For this purpose, the inventory map of 139 groundwater wells (contaminated and non-contaminated with heavy oil) with the seven important factors playing a role in controlling contamination were used. The factors are distance to faults, faults density, groundwater depth, aquifer saturated thickness and hydraulic conductivity, elevation, and distance from Abu Jir fault. For the performance of ANN model, five statistical measures were used namely, accuracy, sensitivity, specificity, kappa, and the relative operating characteristic curve. Obtained results from applying the model in R statistical package indicated that ANN has a high accuracy (> 90%) in training and testing phases. The probability prediction of ANN model was categorized into five groundwater contamination classes: very low-low, moderate, high-very high. The averages of areas occupied by these zones were 5267 km2 (65%), 488 km2 (6%), and 2362 km2 (29%), for very low-low, moderate, and high-very high, respectively. The contamination map developed in this study could be used to drill successful non-contaminated groundwater wells and avoid loss of many efforts in drilling contaminated wells in the study area.

The present study concerned with the heavy elements (Cd, Cr, Ni and Pb) concentration that accumulated in dominant species of aquatic plants (submerged; Ceratophyllum demersum) and (merged; Phragmites australis, Typha domingensis and Schoenoplectus littoralis), in relation to the concentration of these elements in each of the dissolved phase of water and sediments samples which collected seasonally from four sites at Al-Chibayish marshes during August 2017 to April 2018. Also Bioaccumulation factor (BAF) was calculated. The results showed that the highest concentrations of heavy elements was in the sediments, then the aquatic plants and the lowest concentrations was recorded in dissolved phase, whereas the Bioaccumulation Factor (BAF) of heavy elements in aquatic plants, shows that Ceratophyllum demersum have the highest concentration than the other species.