This research is a contribution of indirect analyses to classic geological and structural mapping. The principles of this analysis is to combine structural streams and structural directions in the goal to find structural building of streams network. Streams were numerized under Arcview and the data of each stream was done. Frequency graphics of number and total length of streams on Strahler classification were built and interpreted with “lois des rivières”. Recognition of Structural directions was done by the building of Prud’homme main valleys and Howard drainage anomalies.
Structural streams have affected by at least point 5 in hierarchy. They are held by N30°, N60°, N130°, N160° orientations. This methodology can be applied at all ivoirian drainage system due to their tree buliding. The main valley is host by N60° direction. Others valleys are holding by N30° N130° et EO. in the landscape, structural directions are sitting as drainage anomalies as directions deviations and linear streams. These directions are well knowed in ivoirian precambrian structural context.
The aim of this in this research work is to present an innovative approach to classification of satellite images based on Markov Random Field, MRF. Markov models are used both on single-band and multi-band images and have the advantage to take into account the spatial context in the process of the classification of multispectral images. This leds to the integration of interactions between different pixels and to extract the maximum information contained in satellite images including textures. In this research work, the classification by Markov Random Fields was applied respectively on the colored composites of the first three principal components of multispectral images Landsat TM from 1986 ,ETM + from 2003 and OLI from 2014 of the department of Sinfra containing respectively 94,7% , 97,4% et 98,4 % of the information. Markov Random Field correctly discriminate the different classes of land use with a Kappa coefficient higher than 0.8 : 0.86 for TM images, 0.91 for ETM + and 0.9 for OLI images.
This study shows the potential for discrimination of lithological units of the Precambrian basement with a monoband RADARSAT-1 low spatial resolution (50 m) image. The methodological approach was to produce and exploit a pseudo-panchromatic (15 m) SAR image. SAR image was first denoised then georeferenced using the panchromatic band of Landsat ETM+. The wavelet fusion and multi-resolution analysis technique has been used to produce a pseudo-panchromatic SAR image (15 m) marked "PR". The "Wallis" adaptive filter, synthetic colors transformation and texture parameters calculation were applied to "PR" to enhance the lithological units contours. Primary analysis associated with the interpretation of images deriving from the directional weighted 7x7 Sobel filters, revealed image discontinuities similar to geological fractures. The use of images derived treatments applied to "PR" has allowed bringing out lithostructural various information. According to tone and texture variations, four major geological ensembles consist of mafic and intrapal
The climate variability has affected pejoratively the groundwater recharge in Soubre area. Thus, the simulation of surface flows is an answer to the problematic of water supply in the area. The aim of this study is the simulation of surface flows in Debo catchment by estimating flood flows. The methodology is based on the application of morphological transfer function (MTF) of DEMIURGE software (Digital Elevation Model In Urgency). It consisted of the determination of fractal parameters related to water systems, the estimation of maximum flow at the outlet, the study of the sensitivity of the simulated hydrographs based on the simulation time step. The results show that the reference time is t = 20 minutes. For simulation times different from t = 20 minutes, the geomorphologic pulse histograms (GPH) do not fit the times transfer frequency histogram. The specific flow at the outlet of the catchment is 3.394 m3.s-1 for a rise time of 31.33 hours under the assumption of a uniform effective rainfall of 1 mm. The maximum flows simulated evolve with the rainfall blade and the rushed water. For a blade of 188.08 mm past, the maximum flow rate is at least 634.111 m3.s-1. For a rise time of 33 h 20 minutes, the volumes assessed are estimated at 1.06.108 m3.
This study aims to show the effect of the climatic variability on the productions of coffee and cocoa of the area of Daoukro which is the principal producing area in the Ivory Coast. The methodological approach is summarized in two steps: first, the characterization and analysis of the impact of climate variability on water resources second monitoring developments in the production of coffee and cocoa (1964-2005) through statistical analysis. The centered and reduced index shows a great interannual variability of rainfalls which is organized in two climatic periods, a humid period (1956-1970) and a dry period (1971-2009). The rainfall deficit evaluated in the area of Daoukro reaches an average of 11% and fluctuated between 5% and 15%. Analysis of the average rainfalls of the wettest four months (March-June) every 10 years during five decades of Daoukro station shows that the period of the great season of rains fell from 4 months to 3 months. The decrease of the rainfall consecutive with the effects of the dryness involved a decrease of the agricultural production (the production of coffee and cocoa). The climate variability from 1964 to 2005 caused interannual fluctuation of the production of coffee and cocoa. Cocoa production in 2004-2005 is only 36% of that of 1981-1982 and that of coffee 43% of the production of 1981-1982.
The access to drinking water, in particular in the rural areas and semi-rural in Ivory Coast, constitutes a paramount factor in economic development, the improvement of the standard of living of the populations and their stabilization. The present study aims to raise the unequal distribution of the water supply points for the area of Daoukro and to make a contribution in the research of the zones favorable with the establishment of the productive water supply points in order to allow a good cover of the water needs. The adopted methodological approach is summarized in two stages: initially design of the chart of the water requirements (the access to drinking water) which highlights the zones of deficits followed by the cartography of the sites of establishment of the future water supply points. The knowledge of the space distribution of the population and amongst water supply point by locality made it possible to calculate the access to drinking water of the populations. The analysis of the chart set of themes of the storage areas reveals that nearly 80% of the total surface areas are occupied by zones favorable to the existence of groundwater. The various suitable zones with the establishment of work to large flows were charted and more than 150 sites favorable to the future establishments were selected.
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