This study is based on samples taken from one of the main branches of Tigris River; Gharaf River, at Kut Barrage in Wasit Governorate, Iraq. It aimes to study the quantity and quality of the mollusca Invertebrates; furthermore. The study evaluates the molluscan biodiversity of the rivers by using appropriate biodiversity indexes. Thus, the first of its kind study in the evaluation of the diversity of mollusc in Gharaf River assemblage. Monthly samples were collected randomly from the river mud, for 12 months, from January till December 2016. During the collection process; 5 stations on the river were chosen for sampling with 10(±1) Km distance between each of the stations, including Wasit Governorate. The study showed the presence of 20 Molluscs species were recorded for the first time in Gharaf River. In terms of population density, the annual average for Molluscs was 686.34 Ind./m2 . Relative Abundance Index (Ra) showed that Melanoid tuberculate, Physa acuta and Lymnaea auricularia was less abundant species in Gharaf River. According to the Constancy Index (S) Corbicula fluminalis, M. tuberculata, M. nodosa, Theodoxus jordani, L. auricularia and Physa acuta considered as constancy species in Gharaf’s environment. The highest recorded values of the Species Richness index were 0.0303, while the lowest values were a complete absence (zero). Regarding Jaccard Presence-Community, the results demonstrated that the highest similarity percentage between mollusca communities in Gharraf River was between stations 3 and 5, recorded at 66.66%. In the case of the Shannon-Weiner Diversity Index (H), the diversity values in Gharaf peaked at 7.819 bit/Ind. and a complete absence (zero) at its lowest point. However, the Species Uniformity Index (E) results revealed the highest uniformity values was 1, while, the lowest values were complete absence (zero).
Seasonal variations of the species composition and abundance of Cladocera were studied in two stations at the end of the Tigris River and one station at the confluence of the Tigris with Euphrates area, at the beginning of the Shatt Al-Arab River in Al-Qurnah North of Basrah Province, from October 2015 to August 2016. Samples of zooplankton were collected by plankton net 100-µm. mesh size. The population density of Cladocera ranged between 1 Ind /m³ during summer and 211 Ind./m³ during winter at station 1 (Al-Jewaber Bridge). A total of 16 species of Cladocera belonging to 12 genera were recorded in the study. The average density of Cladocera ranged from 23.2 ind./m3 at Station 2 (Hamayon Bridge) to 53.7 Ind./m3
... Show MoreThe current study was conducted on the southern part of Gharaf River in order to define the physical-chemical properties and the impact of the Tigris River’s floodplain water on its ecological characteristics during 2019. Four sites were selected along the southern part of the river. The findings showed a strong connection between the temperature of air and water at all sites. A value ranging from 4.85 - 84.65 NTU was reported for turbidity. The water was found to be oligohaline, low alkaline, and well ventilated due to high dissolved oxygen concentrations. Gharaf River is considered to be of questionable clean water, according to the results of BOD5. The total a
... Show MoreThis study was the first of its kind on the Dejiala River, which is considered one of the main branches of the Tigris River in Wasit Province. Therefore, the study aimed to investigate of some physical and chemical properties of water in the Dejiala River. Monthly sampling stations were conducted for 12 months, which was starting from January to December 2016, during those five stations was chosen which divided along about 58 Km of river; each station was located at a distance of ±10 Km. The results of the study showed a clear correlation between air and water temperature in all stations. Turbidity was recorded a value ranging from 2.36-116 NTU. It was found that the water of the Dejiala was Oligohaline, weak al
... Show MoreAlien fish species have negative effects on the abundance, diversity and richness of native fish species in southern Iraq. The numbers of alien fish species are constantly increasing due to the entry of invasive species. This has resulted in shifts in the historical composition of fish community structure and scarcity of some native species which represent the keystone in the building of fish populations.
Fish samples were monthly collected from three sites in southern Iraq (Al-Chibyaish marsh, the lower parts of Euphrates River, and the northern part of Shatt Al-Arab River) from April 2017 to June 2018. A total of 14,853 individuals of fish were sampled, which represented 26 species, 24 genera and 13 families
... Show MoreThis study presents a comprehensive list of the freshwater and marine bivalves distributed in Iraq. A total of 51 species were recorded, and distributed as: 14 freshwater species, and 37 marine species, these species belonging to 25 families, all available remarks on the distribution, taxonomy, and nomenclature of these species were given. This study included the recently collected specimens along with those previously studied and recorded in Iraq.
This study covered approximately 150 km from the northern part of the Euphrates River in Iraq. Water and phytoplankton samples were monthly collected from six selected stations from April 2013 to March 2014; three stations were distributed within Hadithah Reservoir, while the three others were in the river's inflow. Water physical and chemical parameters and the phytoplankton community structure were analyzed. The most important results of this study were the diagnoses of 355 phytoplankton species belong to eight phylums. Algal class Bacillariophyceae which belong to phylum Ochrophyta was the most qualitative and quantitative dominant in all stations over the study period. The stations within the reservoir were characterized by higher nu
... Show MoreThis study was conducted to evaluate the effects of Tharthar Arm on the composition and diversity of Rotifera in Tigris River. Six sampling sites were selected, two on Tharthar Arm and four along the Tigris River, one before the confluence as a control site and the others downstream of the confluence. Seventy-seven species of Rotifera were identified in Tigris, whereas, 60 in the arm. The results showed that low density of Rotifera in Tharthr Arm decreased the density in Tigris from 239812.4 upstream of the confluence to 223315.5 at immediate downstream of the confluence. It also declined the mean values of richness, evenness and Shannon diversity indices from 5.19, 0.69 and 2.14 bit/Ind., before the confluence to 3.97, 0.73 a
... Show MoreA morphotectonic analysis is conducted on Shatt Al-Arab drainage basin. This study aims to analysis of the river patterns of Shatt Al-Arab channel and their relationship with the development of subsurface geological structures and the neotectonic activity, as well as an attempt to determine the relative amount to this activity.
Transverse river profile analysis is derived quantifiable and comparable parameters such as neotectonic index (Eh*Ln), Eh, Ch, and Bs. These parameters are useful to detect the morphotectonic indicators of Shatt Al-Arab basin. The analysis showed the role of the subsurface structures that affecting the river cross sections shape, through channel incision, as in (Dair and NuhrUmr) cross sections, while in the ot
The present work included a study of benthic algae on two substrates: rocks and clay on a section of the Tigris River at the Al-Atifiyah site in the fall of 2018. The result of this study was recorded 89 species belong to 50 genus of benthic algae on both substrates and composed of Bacillariophyceae (59.6%, 61.2%), Chlorophyceae (25.8%, 20.4%) and Cyanophyceae (14.5%, 18.3%) respectively on epilithic and epipelic algae. The present study was recorded the highest total algae cell density (1173.2 cells *103/cm2) on epilithic algae while the lowest total algae cell density was recorded on epipelic algae (76.95 cells *103/gm). For measure div
Biodiversity is one of the important biological factors in determining water quality and maintaining the
ecological balance. In this study, there are 223 species of phytoplankton were identified, and they are as
follows: 88 species of Bacillariophyta and were at 44%,70 species of Chlorophyta and they were at 29 %, 39
species of Cyanophyta and they were at 16 %, 12 species of Euglenozoa and they were at 4 %, four species of
Miozoa and they were at 3 %, and, Phylum Charophyta and Ochrophyta were only eight and two species,
respectively and both of them were at 2%. The common phytoplankton recorded in the sites studied
include Nitzschia palea, Scenedesmus quadricauda, Oscillatoria princeps, and Peridinium