Suchergebnisse

German forestry is known for its long history of sustainable forest management. However, a country-level forest inventory (national forest inventory, NFI) with a statistical basis, has only been implemented since the 1960s in the German Democratic Republic (GDR, Eastern Germany), and the 1980s in the Federal Republic of Germany, FRG, Western Germany). This is relatively late when compared to other countries. In this paper, an overview is given of the history of large-area forest assessments in Germany, and the developments towards a national forest inventory. In addition, an elaboration, as well as a brief outlook, are given on the adaptations of this monitoring system over time to the changing needs of a broadening group of stakeholders and interested parties. ; Die Waldbewirtschaftung in Deutschland ist für ihre lange Tradition der Nachhaltigkeit bekannt. Eine nationale Waldinventur auf statistischer Basis fand jedoch erst in den 1960er-Jahren in der DDR und Ende der 1980er-Jahre in der BRD statt; dies ist vergleicchsweise spät im Vergleich zu anderen Ländern. In diesem Aufsatz geben wir einen Überblick über die Geschichte großräumiger Walderfassungen in Deutschland und erläutern die Entwicklung hin zur ersten Bundeswaldinventur in 1987. Wir dokumentieren die Änderungen über die Zeit, die die Bundeswaldinventur erfahren hat in Reaktion auf sich ändernde Anforderungen, und geben einen kurzen Ausblick. ; La gestion des forêts en Allemagne est connue pour sa longue tradition de pérennité. Toutefois, un inventaire forestier national sur une base statistique n'a été réalisé que dans les années 1960 en RDA et à la fin des années 1980 en RFA, ce qui est relativement tardif par rapport à autres pays. Dans cet article, nous donnons un apercu de l`histoire des inventaires forestiers à grande échelle en Allemagne et nous expliquons l'évolution vers le premier inventaire forestier fédéral en 1987. Nous documentons les changements au fil du temps que l'inventaire forestier fédéral a subis en résponse à l'évolution des besoins et nous donnons une brève perspective.

Neglecting tree size and stand structure dynamics might bias the interpretation of the diversity-productivity relationship in forests. Here we show evidence that complementarity is contingent on tree size across large-scale climatic gradients in Europe. We compiled growth data of the 14 most dominant tree species in 32,628 permanent plots covering boreal, temperate and Mediterranean forest biomes. Niche complementarity is expected to result in significant growth increments of trees surrounded by a larger proportion of functionally dissimilar neighbours. Functional dissimilarity at the tree level was assessed using four functional types: i.e. broad-leaved deciduous, broad-leaved evergreen, needle-leaved deciduous and needle-leaved evergreen. Using Linear Mixed Models we show that, complementarity effects depend on tree size along an energy availability gradient across Europe. Specifically: (i) complementarity effects at low and intermediate positions of the gradient (coldest-temperate areas) were stronger for small than for large trees; (ii) in contrast, at the upper end of the gradient (warmer regions), complementarity is more widespread in larger than smaller trees, which in turn showed negative growth responses to increased functional dissimilarity. Our findings suggest that the outcome of species mixing on stand productivity might critically depend on individual size distribution structure along gradients of environmental variation. ; This manuscript was funded by the European Union Seventh Framework Program (FP7/2007–2013) under grant agreement no. 265171, project FUNDIV-Europe, and from project FUNDIVER (MINECO, Spain; CGL2015-69186-C2-2-R). ; J.C. holds a Spanish FPU PhD Grant (FPU12/00575). ; PR-B was granted by the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement No. 265171 (project FunDivEUROPE) and No. PCOFUND-GA-2010-267243 (Plant Fellows). ; Peer reviewed