Preparedness functions in disaster: lesson learned from Tehran dust storm 2014   总被引：1，自引：1，他引：0  

Farin Fatemi  Shandiz Moslehi  Ali Ardalan 《Natural Hazards》2015,77(1):177-179

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An integrated artificial neural network model for the landslide susceptibility assessment of Osado Island,Japan   总被引：1，自引：0，他引：1  

Jie Dou  Hiromitsu Yamagishi  Hamid Reza Pourghasemi  Ali P. Yunus  Xuan Song  Yueren Xu  Zhongfan Zhu 《Natural Hazards》2015,78(3):1749-1776

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Robust optimization of subsurface flow using polynomial chaos and response surface surrogates     

Masoud Babaei  Ali Alkhatib  Indranil Pan 《Computational Geosciences》2015,19(5):979-998

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Probability distribution and extreme value analysis of total suspended particulate matter in Kuwait     

Neelamani Subramaniam  Mane Al-Sudairawi  Ali Al-Dousari  Noor Al-Dousari 《Arabian Journal of Geosciences》2015,8(12):11329-11344

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Erratum to: Mobilization and redistribution of major and trace elements in a lateritic profile: the Sheikh-Marut deposit,NW Iran     

Ali Abedini  Ali Asghar Calagari 《Arabian Journal of Geosciences》2015,8(12):10883-10885

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The effect of the North Atlantic Oscillation on the Iraqi climate 1982–2000     

Salar Ali Khidher  Petter Pilesjö 《Theoretical and Applied Climatology》2015,122(3-4):771-782

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

刘群 《中国海洋湖沼学报》2015,33(4):966-973

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.  相似文献   

Application of a Delay-difference model for the stock assessment of southern Atlantic albacore (Thunnus alalunga)     

Zhang  Kui  Liu  Qun  Kalhoro  Muhsan Ali 《中国海洋大学学报(英文版)》2015,14(3):557-563

Delay-difference models are intermediate between simple surplus-production models and complicated age-structured models. Such intermediate models are more efficient and require less data than age-structured models. In this study, a delay-difference model was applied to fit catch and catch per unit effort(CPUE) data(1975–2011) of the southern Atlantic albacore(Thunnus alalunga) stock. The proposed delay-difference model captures annual fluctuations in predicted CPUE data better than Fox model. In a Monte Carlo simulation, white noises(CVs) were superimposed on the observed CPUE data at four levels. Relative estimate error was then calculated to compare the estimated results with the true values of parameters α and β in Ricker stock-recruitment model and the catchability coefficient q. α is more sensitive to CV than β and q. We also calculated an 80% percentile confidence interval of the maximum sustainable yield(MSY, 21756 t to 23408 t; median 22490 t) with the delay-difference model. The yield of the southern Atlantic albacore stock in 2011 was 24122 t, and the estimated ratios of catch against MSY for the past seven years were approximately 1.0. We suggest that care should be taken to protect the albacore fishery in the southern Atlantic Ocean. The proposed delay-difference model provides a good fit to the data of southern Atlantic albacore stock and may be a useful choice for the assessment of regional albacore stock.  相似文献   

Ecohydrographic constraints on biodiversity and distribution of phytoplankton and zooplankton in coral reefs of the Red Sea,Saudi Arabia          下载免费PDF全文

Benjamin Kürten  Hisham S. Khomayis  Reny Devassy  Saskia Audritz  Ulrich Sommer  Ulrich Struck  Mohsen M. El‐Sherbiny  Ali M. Al‐Aidaroos 《Marine Ecology》2015,36(4):1195-1214

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.  相似文献   

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

Maziar Gholami KORZANI  Ali Akbar AGHAKOUCHAK 《海洋工程》2015,29(1):65-80

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.  相似文献