巴林左盆地烃源岩分布及其特征

巴林左盆地是松辽盆地外围一个断坳叠合盆地,沉积岩厚度10000多米,具有一定的生油成气条件。     

The Dammam aquifer in Bahrain – Hydrochemical characterization and alternatives for management of groundwater quality

 Over-abstraction of the Dammam aquifer, the principal aquifer in Bahrain, by the agricultural and domestic sectors, has led to its salinization by adjacent brackish and saline water bodies. A hydrochemical study identified the locations of the sources of aquifer salinization and delineated their areas of influence. The investigation indicates that the aquifer water quality is significantly modified as groundwater flows from the northwestern parts of Bahrain, where the aquifer receives its water by lateral underflow from eastern Saudi Arabia, to the southern and southeastern parts. Four types of salinization of the aquifer are identified: brackish-water up-flow from the underlying brackish-water zones in north-central, western, and eastern regions; seawater intrusion in the eastern region; intrusion of sabkha water in the southwestern region; and irrigation return flow in a local area in the western region. Four alternatives for the management of groundwater quality that are available to the water authorities in Bahrain are discussed and their priority areas are proposed, based on the type and extent of each salinization source, in addition to groundwater use in that area. The effectiveness of the proposed management options in controlling the degradation of water quality in the Dammam aquifer should be evaluated using simulation modeling. Received: June 1998 Revised: November 1998 Accepted: December 1998     

Effects of reclamation on macrobenthic assemblages in the coastline of the Arabian Gulf: a microcosm experimental approach

Coastal reclamation and modifications are extensively carried out in Bahrain, which may physically smother the coastal and subtidal habitats resulting in changes to abundance and distribution of macrobenthic assemblages. A microcosm laboratory experiment using three common macrobenthic invertebrates from a proposed reclaimed coastal area was preformed to examine their responses to mud burial using marine sediment collected from a designated borrow area. Significant difference in numbers of survived organisms between control and experimental treatments with a survival percentage of 41.8% for all of the selected species was observed. The polychaete Perinereis nuntia showed the highest percentage of survival (57.1%) followed by the bivalve Tellinavaltonis (42.3%) and the gastropod Cerithidea cingulata (24.0%). Quantifying species responses to sediment burial resulted from dredging and reclamation will aid in predicting the expected ecological impacts associated with coastal developments and subsequently minimizing these impacts and maintaining a sustainable use of coastal and marine ecosystems in the Arabian Gulf.     

Creating and sustaining Islamic financial centers: Bahrain in the wake of financial and political crises

Although primarily concentrated in countries with Muslim majorities, Islamic finance has become a global industry representing both a decentering of the global financial architecture and the emergence of an urban network that resides beyond the confines of traditional world city literature. While geographers have identified the “Mecca’s” of the Islamic finance industry – one of which is Bahrain – there remains a need to identify the factors necessary to create and sustain centers of Islamic finance. This paper examines these factors through a firm-level survey of foreign and local Islamic financial institutions in Bahrain, in conjunction with key informant interviews with representatives of these firms. We find that while Bahrain’s entrenched institutional advantages have preserved its role as a center in the Islamic financial landscape, ongoing political instability and the increasing attractiveness of new and emerging centers are threatening this role. As the country navigates the current social and political unrest, questions are raised as to what it takes to be an Islamic financial center.     

Microfungal community associated with rhizosphere soil of Zygophyllum qatarense in arid habitats of Bahrain

Population density and species diversity of microfungal communities were investigated in the rhizosphere soil of the halophytic plant Zygophyllum qatarense inhabiting saline and nonsaline habitats of the arid desert environment of Bahrain. Unlike the nonsaline habitat which is situated in the physiographic zone of multiple escarpment and backslopes, the saline site is located in the coastal lowlands and is featured by high chloride content, electrical conductivity, total soluble salts and low organic matter. Soils of both habitats are sandy, slightly alkaline, poor in nutrient sources, low in water-holding capacity and mainly dominated by a salt-tolerant flora. Quantification of data for the recovery of fungi were based on colony identification and counts by a series of ten-fold dilutions plate method, using various natural, synthetic and selective media. A total of 2780 isolates, fluctuating between 25 and 1109 per sample, were recovered during the present study among all habitats, seasons and plant sizes. Grouping of these isolates has resulted in a maximum of 28 fungal taxa varied between 5 and 15 species, of which 24 were hyphomycetes, 3 ascomycetes and one was an unknown species. All the recorded species in this study, excluding the genus Fusarium, are newly reported from the arid terrestrial habitats of Bahrain. Of the encountered fungi,Cladosporium sphaerospermum was the most dominant and frequent genus, among all plant sizes, followed by Penicillium citrinam and Aspergillus fumigatus, a finding with consistent documented data from similar arid Sahara ecosystems. Examination of data, supported by analysis of relative density values, percentage recovery rates, polar ordination and diversity indices revealed that the nonsaline habitat during the dry period yielded the highest isolate frequency, species abundance, and diversity when compared with the saline habitat. Moreover, a progressive increase in colony occurrence and species diversity was equivalently associated with increment in plant size in the nonsaline habitat. Apparently, the vast majority (moderate to low occurrence class) of the reported species are rhizosphere indigenous saprophytic cellulose-decomposers, whilst the sparse taxa (high occurrence class), e.g. C. sphaerospermum, are regarded as thermo-osmotolerant. Comparison of species richness among samples suggests that small plants inhabiting nonsaline habitats during the wet and dry season were richest in species composition. It is proposed that inter- and intra-specific variation in fungal community between the above habitats reflect not only the influence of plant age and season but also extends to critical multi-soil edaphic and biotic factors involving essentially soil moisture, salinity and root growth dynamic and exudates.