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1.
The Great Green Wall Initiative (GGWI) has an overall objective of fighting desert encroachment through proven practices of sustainable management of land, and the reinforcement and protection of natural resources and systems of production and transformation, while also ensuring socio-economic development of local communities through multi-purpose activity platforms. The activities described in the present study are designed to accomplish several goals: (1) generate wealth, (2) strengthen access to basic social services, (3) manage the transition to a green economy as a means of creating suitable conditions for the emergence of rural production centers, (4) integrate sustainable development in order to eradicate poverty and food insecurity, and (5) strengthen adaptation and resilience capacities of local populations. The present study was undertaken on the basis of a wide variety of available publications and documentation, including articles and scientific papers, thesis, meeting summaries and reports, concerning the implementation of the Great Green Wall Initiative/GGWI in Senegal.  相似文献   
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Correspondence     
E. S. Diop 《Climatic change》1988,13(2):229-227
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A tree survey and an analysis of high resolution satellite data were performed to characterise the woody vegetation within a 10 × 10 km2 area around a site located close to the town of Dahra in the semi-arid northern part of Senegal. The surveyed parameters were tree species, height, tree crown radius, and diameter at breast height (DBH), for which allometric models were determined. An object-based classification method was used to determine tree crown cover (TCC) from Quickbird data. The average TCC from the tree survey and the respective TCC from remote sensing were both about 3.0%. For areas beyond the surveyed areas TCC varied between 3.0% and 4.5%. Furthermore, an empirical correction factor for tree clumping was obtained, which considerably improved the estimated number of trees and the estimated average tree crown area and radius. An allometric model linking TCC to tree stem crosssectional area (CSA) was developed, which allows to estimate tree biomass from remote sensing. The allometric models for the three main tree species found performed well and had r2-values of about 0.7–0.8.  相似文献   
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High nitrate concentrations, above the WHO guideline of 50 mg l−1, were observed in samples of shallow wells reaching the Yeumbeul suburb (Senegal) area groundwater. This groundwater is exploited by 7000 houses and therefore there are health implications. Correlations between parameters such as nitrate content (NO3) in the groundwater and soil water, the distance between shallow wells and family latrines, and soil water chloride (Cl) and colon bacillus content led to two possible sources of groundwater pollution: first, contamination by non impervious and shallow latrines; and second, the leaching of soil NO3 from waste organic matter carried in groundwater.  相似文献   
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This paper establishes various advancements for the application of surrogate modeling techniques for storm surge prediction utilizing an existing database of high-fidelity, synthetic storms (tropical cyclones). Kriging, also known as Gaussian process regression, is specifically chosen as the surrogate model in this study. Emphasis is first placed on the storm selection for developing the database of synthetic storms. An adaptive, sequential selection is examined here that iteratively identifies the storm (or multiple storms) that is expected to provide the greatest enhancement of the prediction accuracy when that storm is added into the already available database. Appropriate error statistics are discussed for assessing convergence of this iterative selection, and its performance is compared to the joint probability method with optimal sampling, utilizing the required number of synthetic storms to achieve the same level of accuracy as comparison metric. The impact on risk estimation is also examined. The discussion then moves to adjustments of the surrogate modeling framework to support two implementation issues that might become more relevant due to climate change considerations: future storm intensification and sea level rise (SLR). For storm intensification, the use of the surrogate model for prediction extrapolation is examined. Tuning of the surrogate model characteristics using cross-validation techniques and modification of the tuning to prioritize storms with specific characteristics are proposed, whereas an augmentation of the database with new/additional storms is also considered. With respect to SLR, the recently developed database for the US Army Corps of Engineers’ North Atlantic Comprehensive Coastal Study is exploited to demonstrate how surrogate modeling can support predictions that include SLR considerations.  相似文献   
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This paper deals with the use, for seismic applications, of a Maxwell element in parallel with a low damping isolator. The study of the properties of the frequency response function shows that this isolator is capable to reduce the base displacement of isolated structures with no considerable amplification of the non‐isolated modes. This is, also, confirmed by the floor response spectra under earthquake excitations. Hence, the previously mentioned isolator does not present the drawbacks met when base displacement is reduced by increasing damping. Moreover, it seems that its performance is comparable with that of more elaborated and expensive techniques combining passive and semi‐active devices. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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In order to manage local rock aggregates efficiently, an inventory has been made of superficial sand materials in the Senegalese basin. A detailed geological study of sandy formations has been undertaken, and geotechnical tests were also performed in order to characterize the sands according to their mechanical properties. The geotechnical characteristics of the sands can be related to their geological histories thus allowing the geotechnical parameters to be estimated by field mapping.  相似文献   
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Accurate estimation of reference evapotranspiration (ET 0 ) is essential for the computation of crop water requirements, irrigation scheduling, and water resources management. In this context, having a battery of alternative local calibrated ET 0 estimation methods is of great interest for any irrigation advisory service. The development of irrigation advisory services will be a major breakthrough for West African agriculture. In the case of many West African countries, the high number of meteorological inputs required by the Penman-Monteith equation has been indicated as constraining. The present paper investigates for the first time in Ghana, the estimation ability of artificial intelligence-based models (Artificial Neural Networks (ANNs) and Gene Expression Programing (GEPs)), and ancillary/external approaches for modeling reference evapotranspiration (ET 0 ) using limited weather data. According to the results of this study, GEPs have emerged as a very interesting alternative for ET 0 estimation at all the locations of Ghana which have been evaluated in this study under different scenarios of meteorological data availability. The adoption of ancillary/external approaches has been also successful, moreover in the southern locations. The interesting results obtained in this study using GEPs and some ancillary approaches could be a reference for future studies about ET 0 estimation in West Africa.  相似文献   
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