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排序方式: 共有482条查询结果,搜索用时 15 毫秒
41.
Tsering Karma Shrestha Manish Shakya Kiran Bajracharya Birendra Matin Mir Lozano Jorge Luis Sanchez Nelson Jim Wangchuk Tandin Parajuli Binod Bhuyan Md Arifuzzaman 《Natural Hazards》2022,110(3):1821-1845
Natural Hazards - The Hindu Kush Himalayan region is extremely susceptible to periodic monsoon floods. Early warning systems with the ability to predict floods in advance can benefit tens of... 相似文献
42.
GeoJournal - This study investigated the effects of voluntary cooperativisationas conducted by the Community-Based Dairy Veterinary Foundation (CDVF) on the livelihood capital of smallholder dairy... 相似文献
43.
44.
Amir Shah Ruddin Md Shah Mashhor Mansor Shahrul Anuar Mohd Shah Che Salmah Mohd Rawi Abu Hassan Ahmad Ibrahim Jaafar 《湿地科学》2008,6(1):34-44
A survey was carried out at the largest rice cultivation area in Peninsular Malaysia,the Muda rice agroecosystem.The main objective of this study was to document the overall biodiversity associated with this unique agroecosystem by using a combination of sampling techniques in order to record different groups of fauna and flora.The total number of biota recorded and identified from the rice field ecosystem during the study period consisted of 46 species of zooplankton,81 species of aquatic insects,5 species of rodents,7 species of bats,87 species of birds,11 species of fishes and 58 species of weeds.A long-term study should be carried out as more species are expected to be recorded when more of the Muda rice agroecosystem area has been sampled to obtain sufficient information on the Muda rice agrobiodiversity. 相似文献
45.
The 3+1 spacetime split is used in a preliminary investigation of waves propagating in a medium of isothermal plasma in the vicinity of event horizon of Reissner-Nordström planar analogue. The general relativistic magnetohydrodynamic equations for isothermal have been investigated there. The dispersion relations are obtained by using linear perturbation and Fourier analyze techniques for non-rotating and rotating, non-magnetized and magnetized environment. The wave number, phase velocity, group velocity etc. are shown to discuss the nature of the waves. 相似文献
46.
Adnan Mohammed Sarfaraz Gani Dewan Ashraf Zannat Khatun E. Abdullah Abu Yousuf Md 《Natural Hazards》2019,99(1):425-448
Natural Hazards - The occurrence of heavy rainfall in the south-eastern hilly region of Bangladesh makes this area highly susceptible to recurrent flash flooding. As the region is the commercial... 相似文献
47.
Hossain Kaizar Yadav Sarita Quaik Shlrene Pant Gaurav Maruthi A. Y. Ismail Norli 《Theoretical and Applied Climatology》2017,129(3-4):1123-1132
Theoretical and Applied Climatology - The rise in the earth’s surface and water temperature is part of the effect of climatic change that has been observed for the last decade. The rates of... 相似文献
48.
Natural Hazards - Infrastructures are the most important aspect of any urban system. Properly planned infrastructures are critical for ensuring services and protecting an urban system from... 相似文献
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50.
Hydrochemical characteristics and quality assessment of shallow groundwater in a coastal area of Southwest Bangladesh 总被引:1,自引:3,他引:1
In this study, the hydrochemical characteristics of shallow groundwater in a coastal region (Khulna) of southwest Bangladesh
have been evaluated based on different indices for drinking and irrigation uses. Water samples were collected from 26 boreholes
and analyzed for major cations and anions. Other physico-chemical parameters like pH, electrical conductivity (EC), and total
dissolved solids were also measured. Most groundwater is slightly alkaline and largely varies in chemical composition, e.g.
EC ranges from 962 to 9,370 μs/cm. The abundance of the major ions is as follows: Na+ > Ca2+ > Mg2+ > K+ = Cl− > HCO3
− > SO4
2− > NO3
−. Interpretation of analytical data shows two major hydrochemical facies (Na+–K+–Cl−–SO4
2− and Na+–K+–HCO3
−) in the study area. Salinity, total hardness, and sodium percentage (Na%) indicate that most of the groundwater samples are
not suitable for irrigation as well as for domestic purposes and far from drinking water standard. Results suggest that the
brackish nature in most of the groundwaters is due to the seawater influence and hydrogeochemical processes. 相似文献