Dendroécolgie du châtaignier (Castanea sativa Mill) en vue de son extension dans l’Akfadou (Tizi ouzou, Algérie).

Abstract - The concept of sustainable forest development is almost unanimously; reconcile economic growth, social demands (increasingly growing and diversified), preservation of ecosystems and their ability to meet multiple needs. However, joint work in collaboration with local residents through participatory management is still needed to develop operational methods and practices that ensure sustainable development, in other words, actions undertake must be economically viable, environmentally sustainable and socially acceptable. To counteract the various degradation factors, safeguard soil fertility and ensure profitable business by generating marketable local products, the use of multiple-use plant species, such as chestnut (Castanea sativa Mill.) seems to be a good long-term strategy. Well suited to Algerian climatic conditions and can be installed on mountainous areas including its fruit which is appreciated by humans for its many nutritional qualities. This aim of this work is to valorize this forest resource through the study of expansion possibilities in mountain areas. They necessarily pass through the mastery of his behavior against environmental factors. The aim is to propose future planting areas and obtaining productive stands. The temperament of the species is addressed by building relationships (by dendrochronology approach) that can explain the influence of environmental factors on radial growth, in order to optimize its operation. The inventory and inspection of plantations established in 1890 and 1948 confirm the adaptation and growth potential of this tree in the mountains of Kabylia (Algeria), a significant fruit production is also noted. However, neglect and lack of maintenance have greatly diminished the vitality of these plantations. 

Keywords: dendroecology, valorization, extension, behavior, chestnut.

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Etude des habitats central et marginal du Merisier au Nord-Ouest de la Tunisie

 
Abstract - Prunus avium is a component of the biodiversity in the forest ecosystems: its fruits are consumed by a large number of birds, its quality of the wood and its premature blooming confer it a big esthetic value. Multipurpose tree, it is present in the forest of Kroumirie in the Northwest of Tunisia. In this region, Prunus avium is a species exploited as a stock for cherry trees and ash wood for the cabinetmaking by the local populations. The natural populating, in constant decrease since a few decades, is threatened by diverse anthropogenic, getting more and more stronger pressures, reducing the capacities of natural regeneration of the species. The study of the ecological housing environment is essential to have a good knowledge of the ecology of such species to determine the conditions in which it develops and to set up appropriate rules of management. Indeed, Prunus avium prefers the lemon-clayey grounds, rich in nitrogen and with a relationship C/N lower than 10. The grounds which it prefers are of acid PH (4.3-6.7). According to the obtained results, such species resists well enough in lower temperatures (T min = 3°C) and is very sensitive to the summer drought (T max = 24°C). At the level of Kroumirie, the presence of Prunus avium is rare below 150 m of height, while it is regularly found in cliff-nesting situation, between 180 and 620 m, with a maximum near 550 m. The obtained results show that such species has an affinity for the lower slopes (0-10 %). Our results allow formulating relative recommendations on the valuation of Prunus avium: practise plantations of this species at the level of the most preferable stations for the production of the wood and the stock for the culture of the cherry tree in the Northwest of Tunisia.

Keywords: Tunisia, Prunus avium, central housing environment, marginal housing environment, environmental factors.

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Fermentation ruminale et Composition chimique de quelques arbustes du Nord de la Tunisie.

Abstract - This study characterized four shrubs in Northern of Tunisia (Erica arborea, Myrtus communis, Arbutus unedo and Phillyrea latifolia) in terms of in vitro gas output and related their organic matter digestibility, metabolizable energy and Total volatile fatty acids (TVFA) with gas production after incubation in rumen juice of goats. The nutritional characterization of shrubs was studied through analysis of the chemical composition, parietal composition, prediction of their nutritional values and analysis of secondary metabolites (total phenols, Flavonoids and tannins). The overall total nitrogen content was less than 10%. Although differences between species and interbreeding were highly significant (p <0.01). The most abundant shrub is Myrtus communis. Arbutus unedo is second only to other species, while Phillyrea latifolia and Erica arborea have low crude protein (CP) content of not more than 2%. The shrubs studied have energy values close to those of concentrated foods and are higher than those of fodder shrubs. The overall mean content of Flavonoids was 20.4; 10.86; 19.26 and 41.38 g EQ / Kg DM respectively in Arbutus unedo, Phillyrea latifolia, Myrtus communis and Erica arborea With significant difference between them (p <0.01). Concerning the overall concentration of tannins at the level of the shrubs studied, it follows the same pace as that of the Flavonoids. The gas volume at. 24 h incubation was higher (p <0.05) for Arbutus unedo and Phillyrea latifolia, while the Myrtus communis Occupies an intermediate position and Erica arboreahas the lowest value. The shrubs studied have comparable digestibility values (p> 0.05). The averages are of the order of 47.83 ± 2.04; 47.14 ± 3.2; 42.86 ± 2.05 and 38.79 ± 3.87% respectively for Arbutus unedo, Phillyrea latifolia, Myrtus communis and Erica arborea.

Keywords: Shrubs, Gas, Chemical composition, Secondary metabolites, Goats.

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Abstract - The ecological basis of forests in Mediterranean countries is quite similar, but the management of ecosystem services differs substantially. The question is which political factors drive the different forest management concepts. Our political analysis looks on private and public actors and their power and interests which shape the management of the ecosystem services of the forests in Tunisia and compares the results with Italy, Portugal and Turkey. We apply an analytical study of interests, conflicts and actor-centered power with a triangulation of qualitative data (document analysis, qualitative interviews and observations) in 2016-2017. We compare our results with the results of ALTERFOR project covering European countries.Thestudy shows that in all cases the key actors are the state institutions, whereas the importance of other actors varies between the countries.In Tunisia and Turkey all forests are state-owned and the governmental institutions dominate forest management. However, in Portugal, actors from timber sector are considerably strong by providing incentives. A particularity of Tunisia is the noticeable impact of international organizations in forest management by the means of incentives and dominant information. In all cases, the shift from government to governance did not happen, but some indicators and previous experiences from other developing countries show the potential in Tunisia.

Keywords: actor-centered power, interests, forest governance, ecosystem services, Mediterranean countries.

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La cueillette des plantes sauvages : exploitation des ressources naturelles et conservation d’un patrimoine naturel.

 
Abstract - In France, the actors of the harvest of plants agree that in the face of the growing demand for plant raw materials, harvesting in the natural environment is intensifying. They mainly concern common species but also species that are rarer, for which the impact of picking remains little known. Furthermore, flora is not an inexhaustible resource and its exploitation raises the question of its sustainability. Legislative tools are available to ensure the protection of plant species under different regimes depending on their conservation status and species-related issues, either defining a strict protection regime or introducing a system of authorization for non-destructive activities, in particular harvesting. Red lists of endangered plants are also defined, based on IUCN criteria and give each species a threat status according to the risk of extinction of the species in the territory concerned. The scientific knowledge on the biology of the species and the empirical knowledge held by the pickers have to be confronted to determine what are the optimal practices of pickings allowing to protect the resource. The French Association of Professionals of the harvesting of wild plants (AFC) promote a responsible harvesting activity, respectful of plant resources. It is supported in its missions by the project of Research-Action "FloreS", carried by the University of Lausanne. Our purpose is to conceal the economic activity of picking plants with the preservation of the populations of wild plants, and to clarify the services of the State in its regulatory options. Together with AFC, we investigate the methods of harvesting – made of knowledge and know-how of the gatherers - and put them in perspective with the biological and ecological characteristics of the picked plants. 

Keywords: harvest, plant preservation, legislative tools, good practices, sustainability, pickers organization.

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Le sacré un cadre structurant la gestion des ressources naturelles dans la Zaouia de Sidi Hamza (Haut Atlas Oriental. Maroc).

 
Abstract – Zaouia Sidi Hamza located on the southern slope of the Eastern High Atlas and backed by the massif of Jbel El Ayachi (3757m), is a mountainous area characterized by multiple streams and sylvo-pastoral ecosystems solicited by different tribes. In fact, these mountain societies have managed to cope with physical constraints, by developing ways of using the environment, to support an economy based on the complementarity between agricultural activity and the exploitation of natural resources. To conduct this study we intend to mobilize a historical approach to analyze the roles of communities in the management of silvo-pastoral resources and define the registers that influence the relationship between man and his environment. It must be emphasized that in this part of the Eastern High Atlas forests and rangelands have a central place. They are a source of material wealth for the neighboring tribes, who benefit from agreements made through negotiations and inter-tribal arrangements. These milieus knew a strong pressure which required the research of the modes of management guaranteeing their equilibrium. We hypothesize that this management is based on the intervention of the institution of Zaouia as a regulator that monitors compliance with the rules of access to resources and intervenes at the time of conflict. Currently, despite this structured management by Zaouia, which continues today, the forest estate is subject to new logics, linked to the exploitation of medicinal plants (Rosemary, Thyme) and knows a process of valuation initiated by the rights holders, customary heirs of land. The integration of market interests by the holders of capital has increased the risk of deterioration and increases the pressure on these resources. Through this example of the Eastern High Atlas, we can ask ourselves if there is no equivalence of the notion of sustainable development in so-called "traditional" societies. And what roles today have traditional regulatory institutions such as Zaouia in the management and preservation of natural resources, in a context marked by the introduction of external actors (state, cooperatives, and investors) who do not recognize its power and its legitimacy.

Keywords: Collective action, Zaouia, Chorfas, Jmaa, holiness, mountain society, sustainability, preservation of natural resources.

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