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Hassan Hamdy Yousef Mohamed S. Fathy Mohamed 《Environmental science and pollution research international》2021,28(5):5482-5494
Environmental Science and Pollution Research - In this work, experimental work is presented on the performance of a hybrid solar distiller comprising solar still (SS) combined with parabolic trough... 相似文献
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Application of geoaccumulation index and enrichment factor for assessing metal contamination in the sediments of Kafrain Dam, Jordan 总被引:6,自引:0,他引:6
Habes A. Ghrefat Yousef Abu-Rukah Marc A. Rosen 《Environmental monitoring and assessment》2011,178(1-4):95-109
An investigation is reported of the degree of metal pollution in the sediments of Kafrain Dam and the origin of these metals. Fourteen sampling sites located at Kafrain Dam were chosen for collecting the surface, cutbank, and dam bank sediment samples. The sediment samples have been subjected to a total digestion technique and analyzed by atomic absorption spectrometer for metals including Pb, Zn, Cd, Ni, Co, Cr, Cu, Mn, and Fe. XRD analyses indicate that the sediments of Kafrain Dam are mainly composed of calcite, dolomite, quartz, orthoclase, microcline, kaolinite, and illite reflecting the geology of the study area. The enrichment factor (EF) and geoaccumulation index (I geo) have been calculated and the relative contamination levels assessed in the study area. The calculations of I geo are found to be more reliable than of those of EF. The enrichment of metals in the study area has been observed to be relatively high. I geo results reveal that the study area is not contaminated with respect to Ni, Co, Cr, Cu, and Mn; moderately to strongly contaminated with Pb; and strongly to extremely contaminated with Cd and Zn. The high contents of Pb, Cd, and Zn in the study area result from anthropogenic activities in the catchment area of the dam site. These sources mainly include the agricultural activities, sewage discharging from various sources within the study area (effluent of wastewater treatment plants, treated and untreated wastewaters, and irrigation return water), and the several industries located in the area. Degrees of correlations among the various metals in the study area are suggested by the results and the intermetallic relationship. 相似文献
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为探究农药和重金属对拟柱孢藻(Cylindrospermopsis raciborskii)的联合毒性效应, 本试验研究了草甘膦和铅单一及联合暴露对其生长、叶绿素含量、光合系统和抗氧化酶的影响. 结果表明:和对照相比,拟柱孢藻的生长率在低浓度草甘膦(0.7 mg·L-1)和铅(0.1和10 mg·L-1)单一暴露时显著升高, 而在高浓度草甘膦(17.1 mg·L-1)暴露时明显降低. 同时, 草甘膦和铅联合暴露与单一暴露相比生长率也显著下降, 表明联合暴露后对拟柱胞藻毒性增强. 联合暴露后荧光诱导曲线初始斜率(M0)、相对可变荧光(VJ)、单位反应中心天线色素吸收的光能(ABS/RC)、反应中心的热耗散能量(DI0/RC)、用于还原QA的能量(TR0/RC)和能量耗散量子比率(φD0)和草甘膦或铅单一暴露相比均显著升高;以吸收光能为基础的性能指数(PIABS)、PSII 潜在活性(FV/F0)、最大光化学效率φP0、t = 0时传递链中超过QA的其他电子受体的概率ψ0和用于热耗散的量子比率φE0则显著降低,说明联合暴露能减少有活性的光合反应中心, 减缓电子传递速率, 造成QA-大量累积. 低浓度的草甘膦和铅单一暴露后和对照组相比叶绿素a含量、PIABS和φE0升高而ABS/RC和DI0/RC降低,表明拟柱孢藻整体光合活性增加. 同时, 草甘膦和铅单一或联合暴露均影响了SOD和CAT活性. 因此,草甘膦与铅联合暴露和单一暴露相比PSII反应中心损伤和电子传递速率抑制加大, 光合效率下降更加明显, 最终影响拟柱孢藻生长. 相似文献
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Yousef Mohammadian Ali Akbar Saboor Yaraghi Hossein Kakooei Mohammad Hajaghazadeh 《毒物与环境化学》2013,95(6):1037-1047
Carbon nanotubes (CNTs) have found numerous applications in various industries. Recently, adverse effects of these materials on human and animal cells in vitro have been reported. In the present study, the cytotoxicity of single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), and chrysotile asbestos in human lung epithelial cells has been studied using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The cells were exposed for 6 h and 24 h to between 0.97 and 1500 μg mL?1 of CNTs and chrysotile fibers prepared in two culture media containing 5% serum and 0.5% dimethylsulfoxide. Dose–response curves were obtained to determine the nonobservable adverse effect concentration and the half-maximum inhibitory concentration (IC50). The way of dispersion affects the cytotoxicity of CNTs. For MWCNT, the toxicological indexes were lower than for SWCNT. Chrysotile fibers were even less cytotoxic than CNTs. Therefore, workplace control measures are recommended as priority for occupational and environmental conditions. 相似文献
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Alahdal Hadil M. Ameen Fuad AlYahya Sami Sonbol Hana Khan Anas Alsofayan Yousef Alahmari Ahmed 《Environmental science and pollution research international》2023,30(10):25050-25057
Environmental Science and Pollution Research - The viral RNA of SARS-Coronavirus-2 is known to be contaminating municipal wastewater. We aimed to assess if COVID-19 disease is spreading through... 相似文献
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Yousef?SakiehEmail author Abdolrassoul?Salmanmahiny 《Environmental monitoring and assessment》2016,188(3):169
Performance evaluation is a critical step when developing land-use and cover change (LUCC) models. The present study proposes a spatially explicit model performance evaluation method, adopting a landscape metric-based approach. To quantify GEOMOD model performance, a set of composition- and configuration-based landscape metrics including number of patches, edge density, mean Euclidean nearest neighbor distance, largest patch index, class area, landscape shape index, and splitting index were employed. The model takes advantage of three decision rules including neighborhood effect, persistence of change direction, and urbanization suitability values. According to the results, while class area, largest patch index, and splitting indices demonstrated insignificant differences between spatial pattern of ground truth and simulated layers, there was a considerable inconsistency between simulation results and real dataset in terms of the remaining metrics. Specifically, simulation outputs were simplistic and the model tended to underestimate number of developed patches by producing a more compact landscape. Landscape-metric-based performance evaluation produces more detailed information (compared to conventional indices such as the Kappa index and overall accuracy) on the model’s behavior in replicating spatial heterogeneity features of a landscape such as frequency, fragmentation, isolation, and density. Finally, as the main characteristic of the proposed method, landscape metrics employ the maximum potential of observed and simulated layers for a performance evaluation procedure, provide a basis for more robust interpretation of a calibration process, and also deepen modeler insight into the main strengths and pitfalls of a specific land-use change model when simulating a spatiotemporal phenomenon. 相似文献
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KATHARINE R. E. SIMS JENNIFER M. ALIX‐GARCIA ELIZABETH SHAPIRO‐GARZA LEAH R. FINE VOLKER C. RADELOFF GLEN ARONSON SELENE CASTILLO CARLOS RAMIREZ‐REYES PATRICIA YAÑEZ‐PAGANS 《Conservation biology》2014,28(5):1151-1159
Natural resource managers are often expected to achieve both environmental protection and economic development even when there are fundamental trade‐offs between these goals. Adaptive management provides a theoretical structure for program administrators to balance social priorities in the presence of trade‐offs and to improve conservation targeting. We used the case of Mexico's federal Payments for Hydrological Services program (PSAH) to illustrate the importance of adaptive management for improving program targeting. We documented adaptive elements of PSAH and corresponding changes in program eligibility and selection criteria. To evaluate whether these changes resulted in enrollment of lands of high environmental and social priority, we compared the environmental and social characteristics of the areas enrolled in the program with the characteristics of all forested areas in Mexico, all areas eligible for the program, and all areas submitted for application to the program. The program successfully enrolled areas of both high ecological and social priority, and over time, adaptive changes in the program's criteria for eligibility and selection led to increased enrollment of land scoring high on both dimensions. Three factors facilitated adaptive management in Mexico and are likely to be generally important for conservation managers: a supportive political environment, including financial backing and encouragement to experiment from the federal government; availability of relatively good social and environmental data; and active participation in the review process by stakeholders and outside evaluators. Mejorando los Objetivos Ambiental y Social Mediante el Manejo Adaptativo en el Programa de Pagos por Servicios Hidrológicos en México 相似文献