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21.
S. Mustapha A. S. Fagam 《International Journal of Environmental Science and Technology》2007,4(3):359-362
A study was conducted to determine the influence of parent material on the contents and distribution of boron and zinc in soils of Bauchi State, Nigeria. Fourty nine, 30, and 20 top 0–30cm soil samples developed from basement complex rock, Kerri-Kerri Formation and Chad Formation, respectively, were collected and analysed using standard laboratory procedures. Results obtained indicate that parent material influenced Zn but not B contents in the soils. Generally, both B and Zn varied widely (CV>30%) between locations in the State, irrespective of the parent material. Organic carbon significantly (P<0.01) and negatively correlated with Zn in soils from BCR (r = ?0.410) and CF (r = ?0.563) and positively with B in soils developed from KKF (r = 0.471) and CF (r = 0.345). With means of 0.41 and 1.46 mgkg?1 for B and Zn respectively, their contents are considered adequate for crop growth. Crops grown on soils in some localized areas identified with values below the critical limits for these micronutrients may, however, benefit from their application. 相似文献
22.
Magnetic mapping for the detection and characterization of UXO: Use of multi-sensor fluxgate 3-axis magnetometers and methods of interpretation 总被引:1,自引:0,他引:1
Marc Munschy Daniel Boulanger Patrice Ulrich Mustapha Bouiflane 《Journal of Applied Geophysics》2007,61(3-4):168-183
Fluxgate vector magnetometers can be powerful instruments in magnetic mapping and in the detection of unexploded ordnance (UXO). Being lightweight and having low power requirements, they allow the development of multi-sensor use. The main problems in using fluxgate magnetometers arise from calibration errors and drift but these can be overcome using a quick and simple method of calibration in the field. This method also has the advantage of compensating permanent and induced magnetic fields generated by magnetized objects carried with the sensors. Measurement accuracy is similar to that obtained with scalar magnetometers. Multi-magnetometer profiling allows direct inversion of raw magnetic data along profiles in order to locate and characterize dipoles typically generated by UXO. The method used is a non-linear inverse procedure that estimates the three coordinates and magnetization vector of the dipole. Application of the technique to both a synthetic case and a field example illustrates the advantages of the method compared with the use of the analytic signal. 相似文献
23.
Authors Index
Index too volume 5 (2001) 相似文献24.
Volume Contents
Volume contents 相似文献25.
Gazi Md. Nurul Islam Tai Shzee YewNik Mustapha R. Abdullah K. Kuperan Viswanathan 《Ocean & Coastal Management》2011,54(2):173-180
This paper examines the impact of Community Based Fisheries Management (CBFM) on fishing households’ welfare in Bangladesh. It analyses how the various types of livelihood assets contribute to fishers’ household incomes. The study found that fishers in CBFM project areas have improved their access to different assets including social, human, physical, financial and natural capitals. The regression results show that social capital contributed significantly to household income, indicating that social factors play very important roles in poverty alleviation in Bangladesh. Future poverty alleviation policy options need to give priority to investments in human, physical and natural capital assets. 相似文献
26.
Greenhouse gas emissions, energy security and sustainability are three of the greatest contemporary global challenges to mankind today. The Sino-German Group of scientists have composed a special issue, which is a collection of diverse quality scientific works, that will try to elucidate the current developments in CO2 geologic sequestration research to reduce greenhouse emission including measures to monitor surface leakage, groundwater quality and the integrity of caprock, while ensuring a sufficient supply of clean energy. 相似文献
27.
CDFSIM: Efficient Stochastic Simulation Through Decomposition of Cumulative Distribution Functions of Transformed Spatial Patterns 总被引:1,自引:1,他引:0
Hussein Mustapha Snehamoy Chatterjee Roussos Dimitrakopoulos 《Mathematical Geosciences》2014,46(1):95-123
Simulation of categorical and continuous variables is performed using a new pattern-based simulation method founded upon coding spatial patterns in one dimension. The method consists of, first, using a spatial template to extract information in the form of patterns from a training image. Patterns are grouped into a pattern database and, then, mapped to one dimension. Cumulative distribution functions of the one-dimensional patterns are built. Patterns are then classified by decomposing the cumulative distribution functions, and calculating class or cluster prototypes. During the simulation process, a conditioning data event is compared to the class prototype, and a pattern is randomly drawn from the best matched class. Several examples are presented so as to assess the performance of the proposed method, including conditional and unconditional simulations of categorical and continuous data sets. Results show that the proposed method is efficient and very well performing in both two and three dimensions. Comparison of the proposed method to the filtersim algorithm suggests that it is better at reproducing the multi-point configurations and main characteristics of the reference images, while less sensitive to the number of classes and spatial templates used in the simulations. 相似文献
28.
The experimental study of the hydrodynamics of the sediments and the physical analysis of the process of exchange at the water-sediment interface in a zone of swash are essential for the understanding of the sedimentary transport processes in coastal environments, in particular to control and forecast the evolution of the coastline. The objective of this study was to exploit the technique of Ultrasonic Doppler Velocimetry (UDV) to examine the evolution of the velocity field at the water-sediment interface in a zone of swash in various conditions of incidental regular waves in a wave flume. The velocities were measured in different conditions of the swash within the sediment bed, and in the fluid vein at the swash edge. These measurements show: an exponential distribution of velocities inside the sediment bed; a difference in the velocity gradient at the water-sediment interface, between the velocity in the water vein at the swash edge and the interstitial flow in the swash. The measurements obtained in the wave flume made it possible to observe an evolution of the velocity profiles according to the phases of the swash, which are characterized by a phase shift between the free flow at the swash edge and the interstitial flow during the two phases of the swash: uprush and backwash. 相似文献
29.
El Mustapha Seghir Hmidou El Ouardi Jeffrey Lindhorst 《Arabian Journal of Geosciences》2017,10(21):467
The aim of this paper is to characterize the geological setting of tin-bearing mineralization at the Bou El Jaj (BLJ) sector, located in the NE termination of the Moroccan Central Massif, South of Meknes city, along the NE-SW-striking shear zone. The main tin mineralization corresponds to a NNE-SSW altered corridor of tourmaline, about 10 to 12 km long, from BLJ to Achmmach mount. The geological structures are affected by three ductile deformation phases D1, (E-W shortening), D2 (NW-SE shortening), and D3 (N-S shortening), overprinting folds, and one brittle deformation event D4 (NW-SE shortening), which was synchronous with alteration and mineralization. The tourmaline-altered sediments occur in two parallel veins, about 2.5 km long and 200 m wide for each one, and are controlled by structures such as bedding, main cleavage, thrusts, and joints. Tin mineralization as cassiterite is always associated with tourmaline alteration and is controlled by the different structures. 相似文献
30.
Bhawan Singh Mustapha El Maayar Pierre André Christopher R. Bryant Jean-Pierre Thouez 《Climatic change》1998,38(1):51-86
The present study involves using the Canadian Climate Centre (CCC) climate change scenario to evaluate the impacts of a CO2-induced climate change on agriculture in Québec and vicinity. Climate change using the CCC General Circulation Model (GCM) data are fed into a crop model (FAO) so as to gauge the changes in agroclimatic factors such as growing season length and growing degree days, and subsequently potential yield changes for a variety of cereal (C3 and C4), leguminous, oleaginous, vegetable and special crops, for twelve major agricultural regions in southern Québec. Our results show that depending upon the agricultural zone and crop type, yields may increase (ex. corn and sorghum by 20%) or decrease (ex. wheat and soybean by 20 to 30%). Also, these crop yield changes appear to be related to acceleration in maturation rates, mainly to change in moisture stress and to shifts in optimal thermal growth conditions. These possible shifts in agricultural production potentials would solicit the formulation of appropriate adaptation strategies. 相似文献