Los esfuerzos para dirección de bosque de alcornoque y sus efectos sobre conservación de suelo, la meseta Shoul, región de Rabat, Marruecos

The Shoul oak grove is a forested ecosystem inherited from a Holocene phase of ecological optimum; its evolution, through the double geologic and human temporality, and in relation with several processes of degradation, led to the progressive loss of its environmental equilibrium and further to the reduction of its economic contributions. The fragility of these forests is the consequence of the convergence of two main factors, i) the intrinsic fragility of the forested environment based on an unstable balance between the tree, the leached soils and their moisture content ; ii) the anthropological action on the forest environment and its degradation with the change of its floristic composition. During the colonization the new context was at the origin of the new social and economic relation between the forest and the surrounding populations. The current use of this oak grove is in a classic scheme of the reports society / forest in Morocco. The population is especially of pastoral main activity in the bordering communes. But the oak groves of Mamora-Sehoul are integrated into the area of influence of several cities, what exposes the forest to the risks of uncontrolled urbanization. These oak groves are thus in the centre of interest of several stakeholders with opposite behaviour and a new paradigm of relation rural/urban. Through a double approach, environmental and socio-economic, this paper will try to bring elements of answer by analyzing the interactions between a forest which reached an alarming threshold of degradation and a society affected by important changes in its modes of intervention and exploitation.La arboleda de roble Shoul es un ecosistema arbolado heredado de una fase de Holocene de grado óptimo ecológico; su evolución, por la doble temporalidad geológica y humana, y en relación con varios procesos de degradación, conducida a la pérdida progresiva de su equilibrio ambiental y con relación a la reducción de sus contribuciones económicas. La fragilidad de estos bosques es la consecuencia de la convergencia de dos factores principales, i) la fragilidad intrínseca del ambiente arbolado basado en un equilibrio(saldo) inestable entre el árbol, los suelos leached y su contenido de humedad; ii) la acción antropológica sobre el ambiente forestal y su degradación con el cambio de su composición floristic. Durante la colonización el nuevo contexto estaba en el origen de la nueva relación social y económica entre el bosque y las poblaciones circundantes. El empleo corriente de esta arboleda de roble está en un esquema clásico de la sociedad de informes / el bosque en Marruecos. La población es sobre todo de actividad pastoral principal en las comunas de lindar. Pero las arboledas de roble de Mamora-Sehoul son integradas en el área de influencia de varias ciudades, que expone el bosque a los riesgos de urbanización incontrolada. Estas arboledas de roble son así en el centro de interés de varios tenedores de apuestas con el comportamiento de enfrente y un nuevo paradigma de relación rural/urbana. Por un doble acercamiento, ambiental y socioeconómico, este papel(periódico) tratará de traer los elementos de respuesta por analizando las interacciones entre un bosque que alcanzó un umbral alarmante de degradación y una sociedad afectada por cambios importantes de sus modos de intervención y explotación

Challenging conservation agriculture on marginal slopes in Sehoul, Morocco

In Sehoul, Morocco, the use of marginal land for agriculture became a necessity for the local population due to increased poverty and the occupation of the best land by new owners. Desertification poses an additional threat to agricultural production on marginal slopes, which are often stony and degraded. In a participatory process embedded in the EU DESIRE research project, potential sustainable land management measures were selected to address land degradation and desertification. Promising experiences with no-tillage practices elsewhere in Morocco had motivated the Moroccan government to promote conservation agriculture throughout the country. This combination of crop rotation, minimal soil disturbance and soil cover maintenance, however, had not yet been tested on sloping degraded land. Field trials of grazing enclosure combined with no or minimum tillage were conducted on the plots of two farmers, and trial results were analyzed based on stakeholders' criteria. Results suggest that increased soil cover with barley residues improved rainwater use efficiency and yields only slightly, although soil water was generally enhanced. Soil moisture measurements revealed that no-tillage was favorable mainly at soil depths of 5cm and in connection with low-rainfall events (<20mm); under these circumstances, moisture content was generally higher under no-tillage than under conventional tillage. Moreover, stakeholder discussion confirmed that farmers in Sehoul remain primarily interested in animal husbandry and are reluctant to change the current grazing system. Implementation of conservation agriculture is thus challenged both by the degraded, sloping and stony nature of the land, and by the socio-economic circumstances in Sehou

Challenging conservation agriculture on marginal slopes in Sehoul, Morocco

In Sehoul, Morocco, the use of marginal land for agriculture became a necessity for the local population due to increased poverty and the occupation of the best land by new owners. Desertification poses an additional threat to agricultural production on marginal slopes, which are often stony and degraded. In a participatory process embedded in the EU DESIRE research project, potential sustainable land management measures were selected to address land degradation and desertification. Promising experiences with no-tillage practices elsewhere in Morocco had motivated the Moroccan government to promote conservation agriculture throughout the country. This combination of crop rotation, minimal soil disturbance and soil cover maintenance, however, had not yet been tested on sloping degraded land. Field trials of grazing enclosure combined with no or minimum tillage were conducted on the plots of two farmers, and trial results were analyzed based on stakeholders’ criteria. Results suggest that increased soil cover with barley residues improved rainwater use efficiency and yields only slightly, although soil water was generally enhanced. Soil moisture measurements revealed that no-tillage was favorable mainly at soil depths of 5cm and in connection with low-rainfall events (<20mm); under these circumstances, moisture content was generally higher under no-tillage than under conventional tillage. Moreover, stakeholder discussion confirmed that farmers in Sehoul remain primarily interested in animal husbandry and are reluctant to change the current grazing system. Implementation of conservation agriculture is thus challenged both by the degraded, sloping and stony nature of the land, and by the socio-economic circumstances in Sehoul

Dynamique de l'occupation du sol et statistiques agricoles sur le bassin versant du Bouregreg au Maroc

Les paysages du bassin versant du Bouregreg ont évolué sous l'effet direct et indirect de facteurs climatiques, pendant les épisodes de sécheresses qui ont touché le pays depuis le début des années 1980. Dans ce contexte, cette étude évalue la dynamique de l'occupation du sol sur l'ensemble du bassin versant (9970 km2) entre 1985 et 2007 à partir de données satellitaires (images Landsat). La méthodologie s'appuie sur l'utilisation de la télédétection et des SIG pour analyser la dynamique des grandes classes d'occupation du sol de la zone d'étude. Ces classes concernent les parcelles agricoles, la végétation naturelle, les sols nus, les surfaces en eau et les zones urbanisées. Les cartes d'occupation du sol ont été produites à partir d'une classification supervisée par maximum de vraisemblance. Elles permettent de mettre en évidence une baisse substantielle du couvert forestier au détriment d'une expansion de cultures céréalières. En outre, les sols dénudés connaissent-ils une augmentation notable de 1985 à 2007. Enfin, le bassin est marqué par une urbanisation continue de la zone littorale. Les observations comparées aux statistiques agricoles confirment cet état de fait. Aussi, l'analyse des rendements des céréales permet-elle de constater une dégradation de la productivité des sols. La chute des rendements est également en forte corrélation avec l'évolution de la pluviométrie, dans un bassin où l'agriculture est essentiellement pluviale. (Résumé d'auteur