Congrès Mondial des Études sur le Moyen-Orient et l'Afrique du Nord

Barcelone, du 19 au 24 julliet 2010


CONSERVING BIODIVERSITY IN THE MIDDLE EAST - 4/5: Impacts on Aquatic Biodiversity in southern Iraq - Salinity and Shatt Al Arab (129) - NOT_DEFINED activity_field_Panel

· NOT_DEFINED institution: Marine Science Center, Basrah (Iraq) /California State University, Sacramento (USA)

· NOT_DEFINED organizer: Prof. Adil Yousif Al-Handal & Dr. Michelle Stevens

· NOT_DEFINED language: English

· NOT_DEFINED description: This panel will assess the impact of land use change and increased salinity on the aquatic biodiversity of the Shatt Al-Arab River and the marine coastal areas of the Gulf. Both locations are vitally important for the provision of ecosystem services to the region. The panel emphasizes papers from scientists in southern Iraq on the loss of biodiversity in the marshes. This panel will have an overview to place the biodiversity loss within the overall context of drainage of the marshes under the Baathist regime, rehydration of the marshes by the Iraqi people, and now the tragic desiccation of marshes thought upstream water diversions and drought exacerbated by climate change.

Chair: Adil Yousif (Marine Science Center, Basrah)

Paper presenter: Mustafa Sami Faddagh (Marine Science Centre, University of Basrah), “Expected genetic variation in fish populations inhabiting Shatt Al-Arab River in Iraq due to fluctuations in water salinity”
The Shatt al-Arab River is a unique estuarine ecosystem, which sustains a wide spectrum of aquatic organisms. Unpredictable fluctuations in salinity levels, caused by freshwater flow reduction from Euphrates, Tigris and Karoon, adversely impacts the existing estuarine ecosystem. Euryhaline fish species inhabiting the brackish water that are physiologically acclimatised to these daily and seasoned fluctuations in salinity have to maintain ion balance by modulate ion flux via the gills. Responding to the habitat alteration is associated with gene functions either in transcriptional or expression aspects. Fish species are immediately threatened by habitat degradation and disruption of ecological factors and have been significantly reduced in numbers and some native populations extirpated. Surviving populations exhibit less genetic variation. Molecular markers developed from expressed sequence tags (ESTs) are efficient to detect gene variation while cDNA library is the most reliable method to investigate differences in the gene expression; both play a role in studying the effect of ecological changes.

Paper presenter: Nadir A. Salman and Majid M. Taher (Department of Fisheries and Marine Resources, College of Agriculture, University of Basrah, Basrah), “Impact of Salinity Changes in Shatt Al-Arab Estuary on Biodiversity of Marine Mammals of the Arabian Gulf”
Salinity changes in the Shatt Al-Arab estuary and North-West Arabian Gulf were monitored and reviewed in terms of the shortage of fresh water inflows to the Shatt Al-Arab. This paper analyses data from previous and current surveys on marine mammals in the area. Eco-physiological investigation was performed to assess the salinity tolerance limits of whales, dolphins and dugong. One third of the world’s 81 species of whales and dolphins, collectively called cetaceans, are thought to occur off the shores in the area. They are divided into the baleen whales - and toothed whales and dolphins. Dolphins or porpoises are more commonly occur in larger numbers. The new check list is prepared according to recent surveys in the neighbouring Arab Gulf countries and the known checklist of mammals in Iraqi waters. Comparison between the North and South areas of the Gulf showed that the ecosystem of the southern parts of the Gulf were more stable than the Northern part. Spatial variation of the marine mammals of the southern part was governed by the occurrence of feeding habitats rather than direct response to salinity variations. Alteration of seaweed’s habitats in response to water pollution is reported to have a direct effect on the biodiversity of mammals in the Gulf. Most of them are related to fishing activities and accidentally killing by ships and boats. The results of this review were discussed in terms of salinity tolerance, hazardous ecological factors and spatial variation.

Paper presenter: Malik H. Ali and H.K. Ahmed (Marine Science Center, University of Basrah), “The impact of low fresh water discharge on community structure of Shrimps at Shatt Al-Arab Estuary and Northern Arabian Gulf with a special reference to Penaeid Shrimp Metapenaeus affinis. ”
Four commercial shrimp species arerecorded in Khour Al-Zubair water Northern Arabian Gulf, the Penaeidshrimps Parapenaeopsis stylifera, Metapenaeus affinis, Penaeussemisulcatus and the Caridean shrimp Exopalaemon styliferus. For M.affinis the fishing ground extends from the south and east of Kuwait Bay north-eastward beyond the mouth of the Shatt Al-Arab; Salinities in these areas are at least 32? This species has long been fished traditionally from the Marshes in Iraq where salinities are around0.4?. The occurrence of M. affinis migration from the Gulf to the marshes in southern Iraq supports the belief that the marshes are a primary nursery ground. Penaeid shrimp that are dependent upon an estuarine phase are particularly subject to the reduction of freshwater flow into estuaries. Recently, the natural flow of freshwater to Shatt Al-Arab estuary is being reduced in the upper reaches of the Tigris and Euphrates rivers. Fresh water shrimps in Shatt Al-Arab and Marshes consist of two species of Caridean shrimps: Atyaephyradesmarestii mesopotamica and Caridina babauliti basrensis, which are more widely distributed but less commercially exploited than penaeids.In 2004, an invader species with high population density, Macrobrachuimnipponense, appeared in the fresh water area. As a conclusion we assert that great fluctuations in the distribution, density and biodiversity of the shrimp populations occurred as a result of the rapid deterioration of estuarine environment.

Paper presenter: Nadia Fawzi and Hamid T. Al-Saad (Marine Science Center, University of Basrah), “Examining the condition of Iraq’s water ways and their impact on the water quality of the north-western Arabian Gulf”
Examining the condition of Iraq’s water ways and their impact on the water quality of the north-western Arabian Gulf. This review examines the changes in water quality that have taken place in the main Iraqi rivers (Tigris, Euphrates, Shatt Al-Arab) and estuary over the past few decade. In particular, this paper will discuss the effects of a reduction in fresh water supply, the pollution of these waterways and the impact of these factors on the north-western Arabian Gulf. Past and present datasets from the southern parts of Iraq have been compiled to assess spatial and temporal water qualities of the Tigris, Euphrates, and the Shatt Al-Arab and to predict the impact of these factors on the north-western Arabian Gulf. The results show changes in the quantity and quality of water due to the effects of upstream damming, which has significantly reduced the water flow to Iraq, particularly with three years of drought. In addition, water quality is continuing to deteriorate due to the absence of adequate river basin management programmes; and the direct dumping of untreated wastes; and agricultural runoff. Reduced water quantity and contaminated water quality are exerting an immense impact with harmful effects on public health. Major evidence for environmental stress is the increasing infringement of marine waters into the Shatt Al-Arab estuary and its tributaries; which is dramatically affecting agricultural activities and the livelihood of farmers residing in the area. Salt water encroachment has introduced invasive marine species. Further studies of these issues are needed to determine the short-term and long-term environmental impacts on both the marshes and the Arabian Gulf.

Paper presenter: Dr. Dawood Salman Abdullah (Department of Marine Biology, Marine Science Center, University of Basra, Iraq), “On the morphology, molecular biology and responses of Artemia franciscana from Basrah to various salinities and temperatures”
The present study make use of both morphometric and molecular biology data to identify the bisexual population of Artemia in Basrah, as there was a great confusion of the nomenclature currently used in Iraq, regarding the identity of the species. A. franciscana was confirmed to occur in Basrah. A parthenogenetic species was also encountered in this region. A comparison of morphometric characters and DNA sequencing data was made for strains of the same species from various localities and with those of different species in the world.
The combined effect of salinity and temperature on the survival, growth and biomass of the local strain of Artemia franciscana were studied. The highest mean survival (93 %) was at 20 °C and 55 ‰ and the lowest mean (8.0 %) was at 35 °C and 115 ‰. The highest average growth attained was 6.14 mm at 30 °C and 115 ‰ and the lowest was 1.49 mm at 10 °C and 95 ‰. The highest average biomass was 122.86 mg dw / L at 20 °C and 55 ‰, whereas the lowest average was 3.79 mg dw / L at 10 °C and 115 ‰. There were significant differences (P<0.05) among all treatments. The present unusual increase in salinity may play a major role in the invasion of the local strain of Artemia into various other localities in the region.