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Copyright of Majalat Monazaat Al-Aamal is the property of Majalat Monazaat Al-Aamal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

IN THE CURRENT STUDY, THE UNIVERSEL SOIL LOSS EQUATION (USLE) IS APPLIED TO MODELING THE SOIL WATER EROSION IN OUED CHERRAT WATERSHED LOCATED IN THE WEST OF MOROCCO. USLE MODEL TAKES IN CONSIDERATION THE MAIN FACTORS THAT INFLUENCE WATER EROSION : RAINFALL, TOPOGRAPHY, SOIL PROPERTIES, THE CONDITIONS OF CROP MANAGEMENT AND CONSERVATION PRACTICES. MANY DATA, FROM VARIOUS SOURCES WAS USED THROUGH THE SPATIAL TOOLS, GIS (GEOGRAPHIC INFORMATION SYSTEMS) AND REMOTE SENSING, TO ASSESS THE RISK OF WATER EROSION. THE RESULTS SHOW THAT 65.7% OF THE STUDY AREA HAS A VERY LOW RISK OF EROSION, 7.7% LOW RISK, 9.9% MEDIUM RISK, 5.4% HIGH RISK AND 11.3% A VERY HIGH RISK. THE SOIL LOSS VARY BETWEEN 0 AND 524.15 T/HA/YR. THE AVERAGE RATE OF EROSION FOR THE ENTIRE WATERSHED IS ESTIMATED TO 12.16 T/HA/YR. PRIORITY AREAS FOR EROSION MANAGEMENT REPRESENT 16.7%. GENERALLY CHARACTERIZED BY HIGH SLOPES, THEY ARE MAINLY LOCATED IN THE UPSTREAM OF THE WATERSHED AND ON THE BANKS OF OUED CHERRAT AND ITS STREAMS. [ABSTRACT FROM AUTHOR]

Nowadays, urban sprawl is one of the major problems facing the Algerian Low-Sahara oases. Monitoring and understanding its spatial evolution remains an essential step for any sustainable development project of the oasis city. Local authorities do not have relevant and updated tools for effective management and spatial planning. Remote sensing and Geographic Information Systems (GIS) provide opportunities to overcome these difficulties. The present study consists in application of a change detection technique to map and quantify the spatiotemporal sprawl of Biskra City (Algeria), during the period 1985 - 2000, using three Landsat images acquired in 1985, 2000 and 2015. The post-classification comparison of land use and land cover maps has revealed a remarkable growth in the built-up areas going beyond the municipality's boundaries, in conurbation with the agglomeration of Chetma, against a progressive decline of the palm grove. It has undergone a continue process of fragmentation and conversion of its surface by the uncontrolled urbanisation, leading to the loss of the original oasis identity distinguishing this city. The main aim of this paper is to highlight the urban sprawl process and its spatial land use and land cover modifications. This study also shows the utility of change detection methods and Geographic Information Systems for monitoring the urbanisation patterns and assessing their impacts on oasis ecosystems. [ABSTRACT FROM AUTHOR]

Slope instability phenomena, by their essentially random nature, generate risks for various elements of mountain heritage. In Man Mountains region of Man, located in the west of Côte d'Ivoire, the manifestation of these phenomena is made more and more because of the rugged terrain and climate change. This study aims to map potential areas of slope instability movements in the Man area to prevent natural damage and/or casualties. The method used in this work, is based on remote sensing, Geographic Information System (GIS) and Saaty's analytic hierarchy process (AHP) method. Six (6) factors involved in the occurrence of landslides such as slope, drainage density, fracturing density, regolith thickness, precipitation, and normalized vegetation index (NDVI) have been mapped. Their integration into a GIS has made it possible to map the region's susceptibility to slope instability movements. Indeed, using Saaty's analytic hierarchy process (AHP) method, a prioritization, a weighting and a classification of the different factors were made. This facilitated the linear combination of the different factors in the GIS. The resulting susceptibility map was field-verified to yield a susceptibility map to slope instability movements of Man area. This map shows classes of very low, low, moderate, high and very high susceptibility. Areas of high and very high instability represent 14.65%. They are located in the West Central of the study area. Majority of these areas are found on the slopes of the Tours and Dan, mountains located between Biankouma and Man, which are characterized by steep slopes and registrate rainfall of more than 1500 mm. [ABSTRACT FROM AUTHOR]

In this study, remote sensing and geographic information systems (GIS) are implemented in order to map and assess water erosion using the Universal Soil Loss Equation (USLE) in the Wadi Mina watershed in Algeria. The study area is characterized by great irregularity in rainfall which is mainly generated during storm events. The region is also known for its steep slopes, marly lithology and very sparse vegetation cover, making it more exposed and vulnerable to erosion. The USLE model can be described as the combination of six factors that feature the specific characteristics of the watershed. Data from multi-temporal remote sensing analysis and GIS are used to individually assess and map each factor. Integration of thematic maps for the USLE factors in the GIS is used to identify the impact of each factor on soil loss, as well as to rank the relative importance of the erosion zones, and further to quantify soil loss in the investigated region. [ABSTRACT FROM AUTHOR]

This paper aims to establish a map of the flood risk of the coastal plain of Saïdia located on the Mediterranean coast of north-eastern Morocco. This plain is enclosed between rivers : the Moulouya in the West and the Kiss in the East. It is bordered to the south by the Ouled Mansour Mountains. These are sheared by very steep ravines that empty directly into the plain. The groundwater is very shallow. This background coupled with geomorphic coastal development promotes the current flood risk. In this paper, the methodology is based on the structuring in a geographic information system (GIS), remote sensing data, products derived from a digital elevation model (DEM) and external data (lithology, the groundwater level, etc.). The analytical approach consists of a digital processing of a GeoEye-1 satellite image and aerial photographs to map the surface states, an extraction phase of topographic attributes and geomorphology of the land, represented by the digital elevation model (DEM) and a phase of structuring information for spatial analysis in a GIS. These investigations allowed the construction of two maps : the map of vulnerability to flood and the map of hazards. The vulnerability map shows that very high vulnerability areas represent 57% of the site and correspond to areas of inter-dunes flat formed by deposits of fine clay, and characterized by lowland sector (0-4 m). The hazard map refers to the land cover. The superposition of these two maps helped to establish the map flood risk. This thematic map shows that approximately 43% of the territory considered is located in high to very high flood risk areas, and correspond to the banks of the Moulouya and the kiss rivers and to the marshes of the Moulouya River, and to the sector on which the new Saidia resort is built. [ABSTRACT FROM AUTHOR]

Water erosion is one of the main causes of degradation of the agro-soil assets. This phenomenon is well known in the catchment area of Tlil river sector involved in this study. Located in the north-east of Tunisia, this basin has a hilly terrain with altitudes ranging from 50 m to 420 m and steep slopes ranging from 2 to 25% and sometimes more. It covers an area of 45 km2 drained by a series of river, mainly Tlil river. The application of the universal equation of soil loss has three key objectives: - The parameter estimation of water erosion that is, the aggressiveness of rainfall, soil erodibility, topographic factor, the index of vegetation cover and erosion control practices factor. - The identification of sensitive areas and high risk of erosion and the areas of emergency response in the watershed. - Quantification of soil loss by runoff. The mapping of these areas is done using the remote sensing and geographic information systems. This will guide the various measures of intervention possible water conservation and soil programmed in the region. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Forestry Faculty of Kastamonu University is the property of Kastamonu University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrology is one of the various fields where the remote sensing and GIS are very useful for solving different practical problems. This paper presents an application of informations acquisitioned by remote sensing and of GIS techniques in regionalization of the annual peak discharges of catchments in Carpathian Curvature area (Romania). The multiple-regression procedure was the applied as regionalization method. The remote sensing and GIS has been used for obtain the variables of the regression models (physiographic characteristics of catchments): area, mean elevation, mean slope, index of form, mean annual precipitation, proportion of forest, and proportion of croplands. The two last variables were determined from the Eurasia Land Cover Database (EDC), with 1 km nominal spatial resolution, and based on 1 km AVHRR data spanning April 1992 through March 1993. We used the classification of the International Geosphere Biosphere Programme's (IGBP) containing 17 land cover classes. The obtained regression models can be used to estimate the annual peak discharges with different interval of recurrence in the study area, from catchments no-gauged or from catchments where the measured data have not a good quality. [ABSTRACT FROM AUTHOR]

Copyright of VertigO is the property of La Revue Electronique en Sciences de l'Environnement VertigO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Regional Science / Revue Canadienne des Sciences Régionales is the property of Canadian Regional Science Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)