The factors controlling the distribution of carbonate content in Kuwait Bay sediments

The present study has been undertaken to determine the nature and the factors controlling the distribution of carbonate content in Kuwait Bay sediments. The carbonate content that may be deposited with Kuwait Bay sediments is attributed to the interplay of the deposits fallout from the dust storms over Kuwaiti territory, the deposits carried in suspension by the currents from Shatt Al-Arab area and to the skeletal parts of microorganisms that may be originated in the sediments. The carbonate content increases in the coarse sediments rather than in the fine sediments. The mineral components of the carbonate present are in the form of calcite, aragonite and some dolomite. Therefore, the texture of the sediments, the rate of deposition in addition to the biological interference may exert a considerable control over carbonate distribution.     

Possible Impacts of Climate Change on Soil Moisture Availability in the Southeast Anatolia Development Project Region (GAP): An Analysis from an Agricultural Drought Perspective

This paper presents probable effects of climate change on soil moisture availability in the Southeast Anatolia Development Project (GAP) region of Turkey. A series of hypothetical climate change scenarios and GCM-generated IPCC Business-as-Usual scenario estimates of temperature and precipitation changes were used to examine implications of climate change for seasonal changes in actual evapotranspiration, soil moisture deficit, and soil moisture surplus in 13 subregions of the GAP. Of particular importance are predicted patterns of enhancement in summer soil moisture deficit that are consistent across the region in all scenarios. Least effect of the projected warming on the soil moisture deficit enhancement is observed with the IPCC estimates. The projected temperature changes would be responsible for a great portion of the enhancement in summer deficits in the GAP region. The increase in precipitation had less effect on depletion rate of soil moisture when the temperatures increase. Particularly southern and southeastern parts of the region will suffer severe moisture shortages during summer. Winter surplus decreased in scenarios with increased temperature and decreased precipitation in most cases. Even when precipitation was not changed, total annual surplus decreased by 4 percent to 43 percent for a 2°C warming and by 8 percent to 91 percent for a 4°C warming. These hydrologic results may have significant implications for water availability in the GAP as the present project evaluations lack climate change analysis. Adaptation strategies – such as changes in crop varieties, applying more advanced dry farming methods, improved water management, developing more efficient irrigation systems, and changes in planting – will be important in limiting adverse effects and taking advantage of beneficial changes in climate.     

Prediction of the sawing quality of Marmarit stones using the capability of artificial neural network

The sawing rate is one of the most significant and effective parameters in extracting building stones via diamond wire sawing. This parameter designates the capability of diamond wire sawing for sawing different stones; in addition, the parameter gives rise to economical considerations for quarry designers. In this study, the existent relations between stone geotechnical parameters and the sawing rate of stones via diamond wire sawing were analyzed using regression and correlation coefficient as well as the collected data from Marmarit stone quarries. Moreover, we estimated the sawing rate of Marmarit using the dimensional stone rock mass rating (DSRMR); upon comparison of the data obtained from DSRMR our pre‐collected data on quarries, we did not gain satisfactory results from DSRMR, hence we used artificial neural network (ANN). The results showed that the percentage of Silica, the coefficient of water absorption, the uniaxial compressive strength (UCS), and abrasive hardness are the proper parameters for creating the ANN. Discontinuities have the least effects possible on diamond wire sawing. Having given the training possibility of the ANN, and its ability to evaluate relations among input parameters, the ANN, which was being trained with Marmarit's traits, was an accurate network for estimating diamond wire sawing in Marmarit quarries, although it could not generalize this network for other stones such as Chini and Crystal. Copyright © 2011 John Wiley & Sons, Ltd.     

Geography of contamination: The location of industrial waste dumps in Catalonia

The handling of the solid industrial waste (SIW) generated in Catalonia is one of the main problems of industrial and territorial policy confronting the public bodies controlling this area of activity. The most recent estimates in this regard indicate that the annual production of SIW is 1,700,000 tons and that only 300,000 tons are treated.In this situation it is usual for a large number of industries to eliminate their SIW furtively, it is common practice to dump waste in various unprepared areas. In this article we present a series of hypotheses which we believe allow us to understand the logic that guides the siting of a large number of these dumps.In the first place we demonstrate the importance of a series of conditions derived from the same industrial logic, to wit, a) the cost of transporting the SIW to the dumps, b) the industrial decentralization process and the metropolitan development of Catalonia, c) vertical integration and the appearance of companies especially dedicated to the elimination of waste and, d) the development of land use through revaluation of the land and greater possibilities for control forces furtive dumps to be sited in more and more distant areas.Secondly, we examine the role of public bodies in this process, concentrating on the characteristics of the legal system and the real effectiveness of urban controls. Finally, in third place, an explanation is given of research carried out in the Barcelona area which shows the importance of the conditions examined above.     

Spatial distribution and temporal variation of reference evapotranspiration in arid and semi‐arid regions of Iran

Analysis of spatial and temporal variations of reference evapotranspiration (ET_o) is important in arid and semi‐arid regions where water resources are limited. The main aim of this study was to analyse the spatial distribution and the annual, seasonal and monthly trends of the Penman–Monteith ET_o for 21 stations in the arid and semi‐arid regions of Iran. Three statistical tests the Mann‐Kendall, Sen's slope estimator and linear regression were used for the analysis. The analysis revealed that ET_o increased from January to July and deceased from July to December at almost all stations. Additionally, higher annual ET_o values were found in the southeast of the study region and lower values in the northwest of the region. Although the results showed both positive and negative trends in annual ET_o series, ET_o generally increased, significantly so in six (～30%) of the stations. Analysis of the impacts of meteorological variables on the temporal trends of ET_o indicated that the increasing trend of ET_o was most likely due to a significant increase in minimum air temperature, while decreasing trend of ET_o was mainly caused by a significant decrease in wind speed. At the sites where increasing ET_o trends were statistically significant, the rate of increase varied from (+)8·36 mm/year at Mashhad station to (+)31·68 mm/year at Iranshahr station. On average, an increasing trend of (+)4·42 mm/year was obtained for the whole study area during the last four decades. Seasonal and monthly ET_o have also tended to increase at the majority of the stations. The greatest numbers of significant trends were observed in winter on the seasonal time‐scale and in September on the monthly time‐scale. Copyright © 2011 John Wiley & Sons, Ltd.     

Evaluation of the fishery status for King Soldier Bream Argyrops spinifer in Pakistan using the software CEDA and ASPIC

Catch and effort data were analyzed to estimate the maximum sustainable yield(MSY) of King Soldier Bream, Argyrops spinifer(Forssk?l, 1775, Family: Sparidae), and to evaluate the present status of the fish stocks exploited in Pakistani waters. The catch and effort data for the 25-years period 1985–2009 were analyzed using two computer software packages, CEDA(catch and effort data analysis) and ASPIC(a surplus production model incorporating covariates). The maximum catch of 3 458 t was observed in 1988 and the minimum catch of 1 324 t in 2005, while the average annual catch of A. spinifer over the 25 years was 2 500 t. The surplus production models of Fox, Schaefer, and Pella Tomlinson under three error assumptions of normal, log-normal and gamma are in the CEDA package and the two surplus models of Fox and logistic are in the ASPIC package. In CEDA, the MSY was estimated by applying the initial proportion(IP) of 0.8, because the starting catch was approximately 80% of the maximum catch. Except for gamma, because gamma showed maximization failures, the estimated results of MSY using CEDA with the Fox surplus production model and two error assumptions, were 1 692.08 t(R 2 =0.572) and 1 694.09 t( R 2 =0.606), respectively, and from the Schaefer and the Pella Tomlinson models with two error assumptions were 2 390.95 t( R 2 =0.563), and 2 380.06 t( R 2 =0.605), respectively. The MSY estimated by the Fox model was conservatively compared to the Schaefer and Pella Tomlinson models. The MSY values from Schaefer and Pella Tomlinson models were the same. The computed values of MSY using the ASPIC computer software program with the two surplus production models of Fox and logistic were 1 498 t(R 2 =0.917), and 2 488 t( R 2 =0.897) respectively. The estimated values of MSY using CEDA were about 1 700–2 400 t and the values from ASPIC were 1 500–2 500 t. The estimates output by the CEDA and the ASPIC packages indicate that the stock is overfished, and needs some effective management to reduce the fishing effort of the species in Pakistani waters.     

Ecohydrographic constraints on biodiversity and distribution of phytoplankton and zooplankton in coral reefs of the Red Sea,Saudi Arabia

An integral concept of ecological research is the constraint of biodiversity along latitudinal and environmental gradients. The Red Sea features a natural example of a latitudinal gradient of salinity, temperature and nutrient richness. Coral reefs along the Red Sea coasts are supported with allochthonous resources such as oceanic and neritic phytoplankton and zooplankton; however, relatively little is known about how the ecohydrography correlates with plankton biodiversity and abundance. In this article we present the biodiversity of phytoplankton and zooplankton in Red Sea coral reefs. Oceanographic data (temperature, salinity), water samples for nutrient analysis, particulate organic matter, phytoplankton and zooplankton, the latter with special reference to Copepoda (Crustacea), were collected at nine coral reefs over ~1500 km distance along the Red Sea coast of Saudi Arabia. The trophic state of ambient waters [as indicated by chlorophyll a (Chl a)] changed from strong oligotrophy in the north to mesotrophy in the south and was associated with increasing biomasses of Bacillariophyceae, picoeukaryotes and Synechococcus as indicated by pigment fingerprinting (CHEMTAX) and flow cytometry. Net‐phytoplankton microscopy revealed a Trichodesmium erythraeum (Cyanobacteria) bloom north of the Farasan Islands. Several potentially harmful algae, including Dinophysis miles and Gonyaulax spinifera (Dinophyceae), were encountered in larger numbers in the vicinity of the aquaculture facilities at Al Lith. Changes in zooplankton abundance were mainly correlated to the phytoplankton biomass following the latitudinal gradient. The largest zooplankton abundance was observed at the Farasan Archipelago, despite high abundances of copepodites, veligers (Gastropoda larvae) and Chaetognatha at Al Lith. Although the community composition changed over latitude, biodiversity indices of phytoplankton and zooplankton did not exhibit a systematic pattern. As this study constitutes the first current account of the plankton biodiversity in Red Sea coral reefs at a large spatial scale, the results will be informative for ecosystem‐based management along the coastline of Saudi Arabia.     

Soil-Structure Interaction Analysis of Jack-up Platforms Subjected to Monochrome and Irregular Waves

As jack-up platforms have recently been used in deeper and harsher waters, there has been an increasing demand to understand their behaviour more accurately to develop more sophisticated analysis techniques. One of the areas of significant development has been the modelling of spudcan performance, where the load-displacement behaviour of the foundation is required to be included in any numerical model of the structure. In this study, beam on nonlinear winkler foundation (BNWF) modeling—which is based on using nonlinear springs and dampers instead of a continuum soil media—is employed for this purpose. A regular monochrome design wave and an irregular wave representing a design sea state are applied to the platform as lateral loading. By using the BNWF model and assuming a granular soil under spudcans, properties such as soil nonlinear behaviour near the structure, contact phenomena at the interface of soil and spudcan (such as uplifting and rocking), and geometrical nonlinear behaviour of the structure are studied. Results of this study show that inelastic behaviour of the soil causes an increase in the lateral displacement at the hull elevation and permanent unequal settlement in soil below the spudcans, which are increased by decreasing the friction angle of the sandy soil. In fact, spudcans and the underlying soil cause a relative fixity at the platform support, which changes the dynamic response of the structure compared with the case where the structure is assumed to have a fixed support or pinned support. For simulating this behaviour without explicit modelling of soil-structure interaction (SSI), moment-rotation curves at the end of platform legs, which are dependent on foundation dimensions and soil characteristics, are obtained. These curves can be used in a simplified model of the platform for considering the relative fixity at the soil-foundation interface.