The Perception and Impact of Natural Hazards on Fishing Communities of Kutubdia Island,Bangladesh   总被引：1，自引：0，他引：1  

Munshi Khaledur Rahman  Thomas W. Schmidlin 《Geographical review》2014,104(1):71-86

Natural hazards lead to unexpected and often dire situations for people who have few resources and little control over the environment in which they live. Kutubdia, an island in the southeastern part of Bangladesh, experiences frequent natural hazards that impact the livelihoods of its people and put them in vulnerable situations. The research elaborated here is the result of 300 household surveys collected from persons in Kutubdia's fishing communities. The surveys investigated the perception and consequences of natural hazards on the fishing communities. The results indicated that the experience of natural hazards—cyclones, erosion, and flooding are examples—have increased over the years. Coastal erosion displaced seventy‐two (24 percent) fishers, forcing them to relocate their houses several times and imposing multiple challenges on their lives. Literacy was not associated with perceptions of environmental changes or changes in fishing. However, young fishers—less than forty years of age—perceived that environmental changes had affected fish catch more than their older colleagues.  相似文献   

Distribution of tritium and stable isotopes in precipitation in Syria     

Abdul Rahman Al Charideh  Boulos Abou Zakhem 《水文科学杂志》2013,58(5):832-843

Abstract

The paper discusses aspects of the isotopic composition (tritium and stable isotopes) of precipitation, which was monitored from 2000 to 2003 at 12 stations in Syria. The seasonal variations in δ¹⁸O are smaller at the western stations than at the eastern ones due to low seasonal temperature variations. A good correlation between δ²H and δ¹⁸O was obtained for each station, and the slopes of the local meteoric water lines are significantly lower than the Global Meteoric Water Line. Values of d-excess decrease from 19‰ at the western stations to 13‰ at the eastern ones, indicating the influence of precipitation generated by air masses coming from the Mediterranean Sea. A reliable altitude effect represented by depletion of heavy stable isotopes (δ¹⁸O and δ²H), of about??0.21‰ and??1.47‰ per 100 m elevation, respectively, was observed. Monthly tritium contents in precipitation, and seasonal variations, are less at the western stations than at the eastern ones. The weighted mean tritium values are between 3 and 9 TU, and increase with distance from the Syrian coast by 1 TU/100 km.

Citation Al Charideh, A. R. & Abou Zakhem, B. (2010) Distribution of tritium and stable isotopes in precipitation in Syria. Hydrol. Sci. J. 55(5), 832–843.  相似文献   

Identification of homogenous regions in Gorganrood basin (Iran) for the purpose of regionalization     

Atefeh Abdolhay  Bahram Saghafian  Mohd Amin Mohd Soom  Abdul Halim B. Ghazali 《Natural Hazards》2012,61(3):1427-1442

Estimation of flood in basins with poor condition of hydrometric stations as in quantity and quality is a dominant problem around the world, mainly in developing country where lack of funds and human resources cause more limitation in number of gauging stations. One of the areas that experience frequent floods and also suffer from small number of stations in Iran is Gorganrood basin. So there is a great need for the estimation and prediction of runoff in this area to prevent any future floods. Due to insufficient station in this area, direct prediction of flood is not applicable. Regional flood frequency analysis is a practical and widely used solution for these situations, which involves the identification of homogenous regions. Gorganrood region was hydrologically homogenized according to the extracted parameters that influence the floods. One of these parameters was Normalized Difference Vegetation Index (NDVI) driven from MODIS images. Curvature is another parameter that relates to topographic attributes. From factor analysis, the most appropriate variables were selected. According to these parameters (NDVI, curvature, area, slope…), the regions were classified into homogenous regions. For the purpose of homogenization, hierarchical (wards) clustering, fuzzy clustering and Kohonen method were applied. L-moment technique was used for the investigation of the results. The heterogeneity measure for one of the groups (Group 1) was more than two; therefore some modifications were applied. The region was grouped into two homogenous subregions. All of the clustering methods showed same results. The models showed that class 4 of NDVI is influential on flood in some return periods. The resulted models can be applied in future studies in different aspects of practical hydrology.  相似文献   

Integrated geoelectrical resistivity,hydrochemical and soil property analysis methods to study shallow groundwater in the agriculture area,Machang, Malaysia   总被引：1，自引：1，他引：0  

Nur Islami  Samsudin Hj Taib  Ismail Yusoff  Azman Abdul Ghani 《Environmental Earth Sciences》2012,65(3):699-712

Integrated geoelectrical resistivity, hydrochemical and soil property analysis methods were used to study the groundwater characteristics of sandy soils within a shallow aquifer in the agriculture area, Machang. A pilot test investigation was done prior to the main investigation. The area was divided into two sites. Test-Site 1 is non-fertilized; Test-Site 2 is the former regularly fertilized site. From the surface to depths of 75 cm, a lower average resistivity was obtained in Test-Site 2 (around 0.37 less than in Test-Site 1). The presence of nitrate and chloride contents in pore water reduced the resistivity values despite the low moisture content. The pH values for the whole area range from 4.11 to 6.88, indicating that the groundwater is moderately to slightly acidic. In the southern region, concentration of nitrate is considered to be high (>20 mg/l), while it is nearly zero in the northern region. In the south, the soil properties are similar. However, the geoelectrical model shows lower resistivity values (around 18 Ω m) at the sites with relatively high nitrate concentration in the groundwater (>20 mg/l). Conversely, the sites with low nitrate concentration reveal the resistivity values to be higher (>35 Ω m). Basement and groundwater potential maps are generated from the interpolation of an interpreted resistivity model. The areas that possibly have nitrate-contaminated groundwater have been mapped along with groundwater flow patterns. The northern part of the area has an east to west groundwater flow pattern, making it impossible for contaminated water from the southern region to enter, despite the northern area having a lower elevation.  相似文献   

Catastrophic movement of rocks and proposed solutions to avoid its risks in the Abu El-Reesh area, northeast Aswan City, Egypt   总被引：1，自引：1，他引：0  

Ashraf Emam  Abdel Hamid S. El-Fakharani  Adel W. Felesteen  Sayed A. Selim  Kamal M. Hafez 《Arabian Journal of Geosciences》2012,5(4):607-616

Catastrophic mass movement of rocks and torrents affected the Abu El-Reesh area, northeast of Aswan City. The present article aims to evaluate the potential catastrophic movement of rocks, delineate the risk zones, and suggest suitable solutions to avoid the potential risks in this area. The sedimentary succession of Abu El-Reesh area is mainly represented by the Nubian sandstone sequence of Upper Cretaceous (up to 60?m thick) forming a huge scarp at the eastern border of the study area. This sequence comprises two vertically successive rock formations: Timsah Shale Formation and Umm Barmil Sandstone Formation. The Timsah Shale Formation forms the lower part of the sedimentary succession with a thickness of 6?C40?m. It is composed of shale beds with intercalations of sandstones, siltstones, and mudstones. This formation is overlain by the Umm Barmil Sandstone Formation, representing the cap rock of the succession, with a thickness of 4?C20?m. The western scarp face has an irregular concave slope, with slope angles ranging from 22° to 46° in the lower part of scarp and become steep (60°?C86°) at its upper part. The drainage patterns are mainly coarse dendritic and discharge into the Nile River, passing through densely populated zones. These zones are exposed to the torrents during rare rainfall events. Three sets of vertical joints (trending NNW, NNE, and WNW) dissect the cap rocks and intersect with the horizontal bedding planes to form separated cubes and polygonal blocks. Potential catastrophic movement of rocks in Abu El-Reesh area is related to several reasons, including: existence of competent sandstones underlain by incompetent shales, dissection of the coherent cap rock due to intersection of vertical joint sets and bedding planes, presence of exposures with steep slopes, rainfall, and human activities (mining works, sewage water, and irrigation). Based on the dominance of either one or more of these reasons, three subareas (El-Khalasab, El-Shadeeda and El-Aqaba) represent the main risk zones, subjected to rock movements and torrents in the study area. Several solutions have been suggested for avoiding the risks related to the potential catastrophic movement of the rocks and torrents in the study area. The fractured rock masses at the top of scarp should be released either mechanically or manually. All buildings that were built on the slope surface of the scarp should be removed. Also, buildings which were constructed in the inlets of wadis and through the rain spillways should be removed. An unsafe boundary separating safe building borders from unsafe zone (with average width 50?m from the base of scarp) is delineated. As a result, resettlement for people living in this unsafe zone should be transferred to another safe area.  相似文献   

Evaluation of the solar photo-Fenton process to treat the petroleum wastewater by response surface methodology (RSM)     

Dheeaa al deen Atallah Aljuboury  Puganeshwary Palaniandy  Hamidi Bin Abdul Aziz  Shaik Feroz 《Environmental Earth Sciences》2016,75(4):333

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Uranium and rare earth elements in Hazm El-Jalamid phosphate,Saudi Arabia: concentrations and geochemical patterns comparison     

Ashraf E. M. Khater  Mahmoud A. Galmed  Mahmoud M. Nasr  Atef El-Taher 《Environmental Earth Sciences》2016,75(18):1261

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Optimization of chlorination boosters in drinking water distribution network for Al-Khobar City in Saudi Arabia     

Muhammad Nadeem Sharif  Ashraf Farahat  Muhammad A. Al-Zahrani  Nilufar Islam  Manuel J. Rodriguez  Rehan Sadiq 《Arabian Journal of Geosciences》2016,9(9):546

Water quality management in distribution networks is directly related to spatial distribution of chlorine boosters and its dosages. Water chlorination is essential to reduce the effects of bacterial and other microbiological contaminants. A higher dosage of chlorine generates harmful by-products in addition to changes in drinking water’s taste and odor. The optimization of chlorine dosage is necessary to decrease the microbial contaminants that affect water quality. Once the chlorine threshold is determined for microbial contaminant, it will help decision makers suggest optimal values. These decisions can rely on the estimated water quality index (WQI). WQI is an index to evaluate water quality and can be linked to adequate residual chlorine with optimal booster dosage, numbers, and locations in water distribution network (WDN). The city of Al-Khobar, Saudi Arabia’s WDN was selected to validate the application of this study. Based on geographic location, the city Al-Khobar water network was divided into five zones. The initial temporal and spatial analysis pointed out poor water quality zones. EPANET, a modeling and simulating software, was applied to evaluate the WQI. Those EPANET results were then integrated with an optimization model. The optimization model suggested new chlorine booster locations to improve water quality in the city of Al-Khobar water distribution network.  相似文献   

First Record of <Emphasis Type="Italic">Porpita porpita</Emphasis> (Cnidaria: Hydrozoa) from the coral reef ecosystem,Bangladesh     

M. Shah Nawaz Chowdhury  S. M. Sharifuzzaman  Sayedur Rahman Chowdhury  Md. Rashed-Un-Nabi  M. Shahadat Hossain 《Ocean Science Journal》2016,51(2):293-297

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Quantifying uncertainties associated with depth duration frequency curves     

Majid Mirzaei  Yuk Feng Huang  Teang Shui Lee  Ahmed El-Shafie  Abdul Halim Ghazali 《Natural Hazards》2014,71(2):1227-1239

Uncertainty in depth–duration–frequency (DDF) curves is usually disregarded in the view of difficulties associated in assigning a value to it. In central Iran, precipitation duration is often long and characterized with low intensity leading to a considerable uncertainty in the parameters of the probabilistic distributions describing rainfall depth. In this paper, the daily rainfall depths from 4 stations in the Zayanderood basin, Iran, were analysed, and a generalized extreme value distribution was fitted to the maximum yearly rainfall for durations of 1, 2, 3, 4 and 5 days. DDF curves were described as a function of rainfall duration (D) and return period (T). Uncertainties of the rainfall depth in the DDF curves were estimated with the bootstrap sampling method and were described by a normal probability density function. Standard deviations were modeled as a function of rainfall duration and rainfall depth using 10⁴ bootstrap samples for all the durations and return periods considered for each rainfall station.  相似文献