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-The small scale forest holdings are very common in Europe, but their management is not well known. The classical principes of forest management and of silviculture being rarely applied, their management is often seen as purely opportunistic, and even chaotic. To overcome this first sight, a detailed analysis of management practices in six private woodlots from two municipalities in south western France was done, with semi-directive interviews of the owners and an dynamic analysis of a chronological series of aerial pictures. The "said" practices (from the interviews) and the "seen" practices (from the aerial pictures) were crossed in a GIS and allowed to build the chronology of logging operations in any points of the woodlots from 1938 to 2003. The data from interviews and from aerial pictures fit together provided useful complementary information. They showed that there were no permanent spatial management unit, the logged areas being defined according to the local and current conditions. The silvicultural strategies and their dynamic have been described. The spatial-temporal complexity of the social and technical factors of the logging decision was acknowledged as a key explanation of the discrepancy between these small scale silvicultural systems and the classical systems.coppice / fragmented forest / forestry practices / logging dynamic Résumé -Variabilité des régimes de coupes dans des taillis de petites forêts fragmentées du sud-ouest de la France. La petite propriété forestière est très commune en Europe, mais sa gestion est mal connue. Les grands principes d'aménagement et de sylviculture la pénétrant très peu, sa gestion est souvent perçue comme purement opportuniste voire chaotique. Pour dépasser cette première approche nous procédons à une analyses fine des pratiques de gestion dans six petits bois privés de deux communes du sud-ouest de la France, au moyen d'entretiens semi-directifs avec les propriétaires et d'analyses d'une série de photos aériennes. Une méthode d'interprétation dynamique des photos aériennes est mise en oeuvre. Les pratiques « dites », les pratiques « observées » et leur croisement dans un SIG permettent de décrire la suite des coupes réalisées en chaque point des six bois de 1938 à 2003. Les données issues des entretiens et des photos se contredisent rarement et se complètent utilement. Nous montrons qu'il n'existe pas d'unités de gestion permanentes, les unités de coupe étant définies de manière conjoncturelle. Nous décrivons les stratégies sylvicoles au moyen de plusieurs indicateurs et montrons leur évolution. L'étude met l'accent sur la complexité de l'organisation spatio-temporelle des coupes et des facteurs techniques et sociaux permettant de l'expliquer, et analyse la cohérence de stratégies sylvicoles en rupture avec les évolutions de la filière-bois internationale.taillis / forêt fragmentée / pratiques forestières / dynamique des coupes

Interdisciplinary research frameworks can be useful in providing answers to the environmental challenges facing rural environments, but concrete implementation of them remains empirical and requires better control. We present our practical experience of an interdisciplinary research project dealing with non-industrial private forestry in rural landscapes. The theoretical background, management, and methodological aspects, as well as results of the project, are presented in order to identify practical key factors that may influence its outcomes. Landscape ecology plays a central role in organizing the project. The efforts allocated for communication between scientists from different disciplines must be clearly stated in order to earn reciprocal trust. Sharing the same nested sampling areas, common approaches, and analytical tools (GIS) is important, but has to be balanced by autonomy for actual implementation of field work and data analysis in a modular and evolving framework. Data sets are at the heart of the collaboration and GIS is necessary to ensure their long-term management and sharing. The experience acquired from practical development of such projects should be shared more often in networks of teams to compare their behavior and identify common rules of functioning.

International audienceUneven-aged management of conifer plantations is proposed as a way to increase the value of these forests for the conservation of bird diversity. To test this assumption, we compared the impact of four common silvicultural systems on bird communities, defined by cutblock size (large in even-aged silvicultural systems/smaller in uneven-aged silvicultural systems) and tree species composition (spruce/beech) in the Belgian Ardenne where beech forests have been replaced by spruce plantations. The abundances of bird species were surveyed in young, medium-aged and mature stands in 3–5 forests per silvicultural system (66 plots in all). The effect of silvicultural systems on bird species richness, abundance and composition were analysed both at the plot and at the silvicultural system levels. In plots of a given age, beech stands were richer in species. The composition of bird species at the plot level was explained by stand age and tree composition, but weakly so by stand evenness. For the silvicultural systems, bird species richness was significantly higher in even-aged and in beech forests, and bird species composition depended on the silvicultural system. This study emphasises the importance of maintaining native beech stands for birds and suggests that uneven-aged management of conifer plantations does not provide a valuable improvement of bird diversity comparatively with even-aged systems