期刊名称：Science et changements planétaires / Sécheresse
印刷版ISSN：1147-7806
电子版ISSN：1777-5922
出版年度：2004
卷号：15
期号：4
页码：307-320
出版社：John Libbey Eurotext
摘要：Figures See all figures Authors Kawtar Fikri Benbrahim , Mohammed Ismaili , Sanae Fikri Benbrahim , Abdellatif Tribak Laboratoire de biotechnologie et amélioration de la production végétale, Faculté des sciences et techniques, Fès–Saïss, BP 2202, Route d’imouzzer, Fès, Maroc, Laboratoire de microbiologie et de physiologie des symbioses, Faculté des sciences de Meknès, BP 4010, Beni M’hamed, Meknès, Maroc, UFR de biologie, Université Joseph Fourier, Grenoble 1, 2231, rue de la piscine, 38400 Saint Martin d’Hères, France, Laboratoire de géomorphologie, Faculté des lettres et des sciences humaines de Fès-Saïss, BP 59, Route d’Imouzzer, Fès, Maroc Key words: Degradation, Desertification, Deforestation, Erosion, Anthropic Factor, Morocco Page(s) : 307-20 Published in: 2004 Increasing pressure on natural resources and hard climatic conditions generate terrestrial ecosystem dysfunctions. These effects are amplified by an inappropriate use of the existing natural resources, thereby leading to the regression of forest clumps, the decrease of water supplies and water pollution, soil degradation, and hence to desertification and reduction of animal and plant diversity. Such disruptions affecting the biological resources and the earth supplies also affect the lives of the people who end up leaving their fields to move to neighbouring cities or emigrate. New techniques of environmental remediation are available to enhance production and protect ecosystems, but unfortunately, social and economic issues are reducing these advances to nothing. Arable land expansion leads to deforestation and to overgrazing, which causes water and wind erosions. All these factors along with drought, topography, soil and vegetation overuse, as well as farming systems, contribute to the desertification process in semiarid zones. The soil’s chemical, physical and biological properties undergo important changes which play an essential role in causing vulnerability to desertification due to human activities. This phenomenon prevents the reconstitution of the vegetal cover and can be considered as the ultimate form of soil degradation. The aim of this paper is to gather new data as to the impact of these phenomena in Morocco and to study the different contributing factors. For a better understanding of their importance, it appeared necessary to briefly assess them worldwide on the one hand, and in the African context on the other. This paper shows the overall important part of anthropic actions on land degradation in Morocco, and evaluates the level of water erosion in Northern Morocco (Rif and pre-Rif areas), of wind erosion in Southeastern Morocco (Drâa and Ziz valleys), of overgrazing in Eastern Morocco, of salinity in Southwestern Morocco, and of deforestation. It also shows that even though drought and hard climatic conditions can contribute to desertification, the latter is mainly due to changes in the ways man uses natural resources, more particularly overgrazing, land clearance, crops, and more generally inappropriate land use.
