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1.
Qadri S. M. Talha Islam Md. Aminul Shalaby Mohamed Ragab 《Natural Resources Research》2019,28(2):369-392
Natural Resources Research - This study addresses the three-dimensional (3D) petrophysical modelling and volumetric analysis of the Farewell Reservoir in the Kupe Field in the southern Taranaki... 相似文献
2.
Riaz Hossain Khan Muhammad Qumrul Hassan Mohammad Saiful Islam 《Environmental Earth Sciences》2013,69(8):2499-2512
Water quality and hydrochemistry of Shariatpur district were evaluated in terms of hydrochemical composition and some important physico-chemical parameters. The groundwater of the study area is good for drinking, domestic as well as for irrigation purposes. Among the major ions, shallow tube well waters give higher concentration of Ca2+ which ranges from 24 to 260 mg/L. The deep tubewell waters show higher concentration of Na+ which varies from 74 to 582 mg/L during dry season. Among the trace elements most of the shallow aquifer samples show higher concentration of Fe2+, Mn2+ and As. Concentration of Fe2+ varies from 0.655 to 18.8 mg/L, and Mn2+ from trace to 0.868 mg/L during dry period. Hydrochemical analyses reveal significant seasonal variation in water quality of shallow aquifer. Both the shallow aquifer and the surface water of the study area are predominantly of Ca–Mg–HCO3 type, while the deep aquifer water is mainly of Na–K–Cl–SO4 type with slight inclination to Ca–Mg–HCO3 type. The study area is suitable for groundwater development if comprehensive and holistic approaches towards water resource management are taken into consideration. 相似文献
3.
To monitor heat losses using Landsat 7 thermal infrared data from 2002 to 2010 within the active fumarolic region of Kuju volcano in Japan, we used the Stefan-Boltzmann equation for radiative heat flux (RHF) estimation. Heat discharge rate (HDR) was calculated by using the relationship coefficient of RHF and HDR, obtained from two previous studies. The highest total RHF was found to be about 57.7 MW in 2002 and the lowest was about 21.1 MW in 2010. We found the highest HDR, of about 384.5 MW, in 2002 and the lowest, of about 140.8 MW, in 2010. The RHF anomalous areas were showing a declining trend during our study period. The relationship between the land surface temperature (LST) above ambient and RHF was, as expected, in a strong correlation for each result during our study period. Overall, our study was able to delineate the declining trend of heat losses that supports a previous study of similar declining trend of HDR using steam maximum diameter method from the active fumarolic region of Kuju volcano. 相似文献
4.
Jean-Louis Grimaud Celine Grall Steven Goodbred Michael S. Steckler Ryan Sincavage Jennifer L. Pickering Chris Paola Leonardo Seeber Md. Saddam Hossain 《Basin Research》2020,32(5):1242-1260
Subsurface deformation is a driver for river path selection when deformation rates become comparable to the autogenic mobility rate of rivers. Here we combine geomorphology, soil and sediment facies analyses, and geophysical data of the Late Quaternary sediments of the central Garo-Rajmahal Gap in Northwest Bengal to link subsurface deformation with surface processes. We show variable sedimentation characteristics, from slow rates (<0.8 mm/year) in the Tista megafan at the foot of the Himalaya to nondeposition at the exposed surface of the Barind Tract to the south, enabling the development of mature soils. Combined subsidence in the Tista fan and uplift of the Barind Tract are consistent with a N-S flexural response of the Indian plate to loading of the Himalaya Mountains given a low value of elastic thickness (15–25 km). Provenance analysis based on bulk strontium concentration suggests a dispersal of sediment consistent with this flexural deformation—in particular the abandonment of the Barind Tract by a Pleistocene Brahmaputra River and the current extents of the Tista megafan lobes. Overall, these results highlight the control by deeply rooted deformation patterns on the routing of sediment by large rivers in foreland settings. 相似文献
5.
Md. Mokhlesur Rahman Muhammad Qumrul Hassan Mohammad Saiful Islam S. Z. K. M. Shamsad 《Environmental Geology》2000,40(1-2):31-40
This paper deals with an environmental impact assessment of low water flow in the river Ganges during a dry period at the
Khulna and Mongla port areas in south-western Bangladesh. Large-scale surface water withdrawal in India after commissioning
the Farakka Barrage causes a drastic fall in the Ganges low-flow condition within the Bangladesh territory during every dry
period. The average lowest discharge in the Ganges is 552 m3/s, which is about 73% less than that in the pre-Farakka time. This has caused the deterioration of both surface and groundwater
quality of the study area. Salinity is the principal cause of water quality degradation in the area. Present observation shows
that the surface water of the area is sulphate-chloride dominated, which signifies high salinity whereas the groundwater is
categorized as of medium to high salinity. To maintain the Rupsa River's maximum salinity below 1000 μS/cm the discharge in
the Ganges should be ∼1500 m3/s, whereas that at Garai basin is ∼10 m3/s. If this present situation continues it will be a crippling blow to the environment of the area in the long term. An integrated
multidisciplinary approach to hydrogeological research is urgently required to salvage the area from further deterioration.
Received: 9 August 1999 · Accepted: 8 March 2000 相似文献
6.
Md Feroz Islam Hans Middelkoop Paul P. Schot Stefan C. Dekker Jasper Griffioen 《水文研究》2021,35(4):e14119
The Ganges-Brahmaputra-Meghna (GBM) delta plain within Bangladesh is one of the most vulnerable to relative sea level rise (RSLR) in the world especially under current anthropogenically modified (i.e., embanked) conditions. Tidal river management (TRM) as practiced in coastal regions of Bangladesh may provide an opportunity to combat RSLR by raising the land level through controlled sedimentation inside beels (depression within embanked polders) with re-opening of polders. To date, TRM has been applied to tide-dominated coastal regions, but the potential applicability of TRM for the beels within the polders of river-dominated and mixed flow (MF) regimes remains to be assessed. We apply a calibrated 2D numerical hydromorphodynamic model to quantify sediment deposition in a beel flooded through breaching of the polder dike under conditions of river-dominated, tide-dominated and MF regimes for different seasons and applying different regulation schemes for the flow into the beel. Simulation results show considerable seasonality in sediment deposition with largest deposition during the monsoon season. The potential of controlled flooding is highest in the tide-dominated region, where sediment accumulation can be up to 28 times higher than in the river-dominated region. Regulating flow into a beel increases trapping efficiency, but results in slightly lower total deposition than without regulation. We conclude that re-establishing flooding of the beel within the polder without regulating the flow into the beel through breaching of the polder dike is a promising strategy for the mixed and tide-dominated flow regions in the delta as the sediment accumulation can raise the land surface at a higher rate than RSLR and effective SLR (ESLR). In the more upstream river-dominated section of the delta, accumulation rates would be much lower, but the pressure of sea level rise on these areas is lower as well. Owing to the abundant availability of sediment, application of controlled flooding like TRM therefore provides an opportunity to counteract the impact of RSLR and ESLR by means of land raising, particularly along the tidal river reaches in the GBM delta. 相似文献
7.
K M Azam Chowdhury Wensheng Jiang Guimei Liu Md Kawser Ahmed Shaila Akhter 《海洋学报(英文版)》2022,41(4):23-39
In the northern Bay of Bengal, the existence of intense temperature inversion during winter is a widely accepted phenomenon. However, occurrences of temperature inversion during other seasons and the spatial distribution within and adjacent to the Bay of Bengal are not well understood. In this study, a higher resolution spatiotemporal variation of temperature inversion and its mechanisms are examined with mixed layer heat and salt budget analysis utilizing long-term Argo(2004 to 2020) and RAMA(2... 相似文献
8.
Distribution of phytoplankton community in relation to environmental parameters in cage culture area of Sepanggar Bay,Sabah, Malaysia 总被引:2,自引:0,他引:2
This paper covers spatial and temporal variation in phytoplankton communities and physico-chemical water properties in the cage culture area of Sepanggar Bay, Sabah, Malaysia based on field measurement conducted during July 2005 to January 2006 to study the spatial and temporal variation in phytoplankton communities and physico-chemical water properties of the bay. Phytoplankton samples and water parameters data were collected from five different stations located inside the bay during Southwest, Interseasonal and Northeast monsoons. Forty phytoplankton genera, representatives of 23 families, were found in the study area with a mean abundance of 1.55 ± 1.19 × 106 cells L−1. Most of these genera belong to diatoms (82.17%), Dinoflagellates (17.55%) and cyanobacteria (0.29%). Three genera were found to be dominant (>10%) in phytoplankton abundance and these were Coscinodiscus spp. (36.38%), Chaetoceros spp (17.65%) and Bacteriastrum spp. (10.98%). The most dominant genus was Coscinodiscus spp. which showed high abundance during all monsoons and stations (except Station 3). Among the seven environmental parameters tested in this study, water temperature, pH and suspended sediment concentration were found to be significantly different between monsoons. On the other hand, no significant differences were found between stations for the studied physico-chemical parameters. A clear differences in phytoplankton densities were observed between monsoons and stations with higher mean abundances during interseasonal monsoon (2.40 ± 1.37 × 106 cells L−1) and at station five (2.05 ± 0.74 × 106 cells L−1), respectively. Conversely, the diversity indices, both Shannon–Wiener (H′) and Pielou (J′), showed no significant difference throughout stations and monsoons (except (H′) for monsoons). Analysis of similarity (ANOSIM) results demonstrated temporal differences in phytoplankton community structure with highly diverse phytoplankton assemblage. Through cluster analysis five groups of phytoplankton were attained (at 40% similarity level) though no marked separation of the taxonomic classes pointed towards the constant pattern of the phytoplankton assemblage in the studied area. 相似文献
9.
Sumi Kanij Rukshana Kim Soo Cheol Howlader Jewel Sharker Md Rajib Choi Kap Seong Choi Sang Ki Park Jong-In Nou Ill-Sup Kho Kang Hee 《Ocean Science Journal》2019,54(3):363-374
Ocean Science Journal - A carbonic anhydrase VII gene, encoding 277 amino acids, was identified in the intestinal tissue of pufferfish (Takifugu rubripes). The translated protein with an 833-bp... 相似文献
10.
Bernerd Fulanda Cosmas Munga Jun Ohtomi Melckzedeck Osore Robinson Mugo Md. Yeamin Hossain 《Ocean & Coastal Management》2009,52(9):459-466
The current study was carried out over a period of one year to characterise the coastal migrant fishery of Kenya. The study looked at gears and vessels used, and ownership, demographic factors including ages of the fishers and family sizes, migrant activity and resource conservation at two main fishing villages in Kenya; Vanga and Mayungu in the south and north coasts, straddling at 4.663°S and 39.215°E and 3.214°S and 40.135°E respectively. Further, the fishers were categorised with regard to fishing, gear and vessel operation and trade, and evolution upon entry into the fishery was also assessed in order to define fisher-stake in the fishery for resource management and conservation planning. Structured questionnaires were used to interview the fishers, and data and information recorded from 1018 fishers during the survey. Migrants accounted for over 63% of the fishers in the two study sites, with majority of the fishers lying in the 15–45 year age bracket. Dependence level averages at 4–6 person families per fisher. Entry to the fishery was mainly at seamen level, progressing to fishermen and finally to fish dealers (tajiris), with the latter holding >62% capital in the fishery. Resource management in the fishery was low and only 10% of the fishers were active participants in marine conservation and community beach management issues. Fisher migrations were mainly monsoon season-linked (>58%) although social factors such as family location determined to a great extent the expanse of the migrations. The revival of fisheries cooperatives and active participation in community resource management and conservation groups is envisaged as the key to the sustainability of both the marine resources and the economies associated with this high mobility, cross-border fishery. 相似文献