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33 years after the last felling: On the development of stand structure in the strict forest reserve "Grosser Freeden" (Teutoburg Forest, Germany)
No full textTitle of the paper: 33 years after the last felling: On the development of stand structure in the strict forest reserve "Grosser Freeden" (Teutoburg Forest, Germany). The forest district "Grosser Freeden" is situated in the northwestern Teutoburg Forest (Lower Saxony, northwest Germany) and became a strict forest reserve in 1972. We investigate how the deciduous forest stands in this reserve evolved after the cessation of timber harvesting and which biotic and abiotic factors led to the current status. In this context, forest history is considered as well. In former times, the investigation area was owned by the prince-bishopric of Osnabruck. Following owners were the Kingdom of Hanover, Prussia and since 1945 the federal state of Lower Saxony. Nowadays, one-storied Fagus sylvatica L. stands are growing on the southern slope that is covered with thick, loess-derived soils. The steep northern slope is dominated by two-storied Fagus sylvatica stands with several secondary tree species, the Rendzina soil is quite shallow (Tab. 1). Even 33 years after the last harvesting operations, it is still apparent how the stands had once been managed. However, tree species that are not site-adapted or less competitive (e.g. Picea abies (L.) Karst. or Ulmus glabra Huds.) are increasingly being replaced by the competitive Fagus sylvatica. Hence, during the observation period (1971-2004), tree-layer diversity decreased, while tree-layer Volume increased (Tab. 2, 4, 5, Fig. 2, 3). Besides high tree mortality due to competition, a considerable dieback of Ulmus glabra occurred, which can be explained by the Dutch elm disease temporary drought stress. Regarding Acer pseudoplatanus L., the analysis of a real time series reveals that this tree species grows faster than Fagus sylvatica in early stages (Fig. 4). The difference of rate of growth between these two tree species decreases with increasing age, until finally Fagus sylvatica overgrows Acer pseudoplatanus. In contrast, Fraxinus excelsior L. grows better than Fagus sylvatica. This trend increases during the last two decades of the observation period and can be explained by a combination of site factors and stand history (Tab. 3). The volume of decaying wood amounts in average to 34 m(3) per hectare (Tab. 6). Due to the protection of natural processes the abundance of decaying wood will increase in the future. Especially in homogeneous and one-storied Fagus sylvatica stands a considerable number of trees will die back in the next decades. In 2004, we found almost no tree regeneration due to Fagus sylvatica competition and very high Population density of fallow deer (Dama dama L.). Since 2005, fallow deer numbers have been reduced by intensified hunting. As a consequence, the forest can develop in a more natural way henceforth. For future stand structure and tree species composition, especially disturbances such as wind throw will be crucial
33 years after the last felling: On the development of stand structure in the strict forest reserve "Grosser Freeden" (Teutoburg Forest, Germany)
No full textTitle of the paper: 33 years after the last felling: On the development of stand structure in the strict forest reserve "Grosser Freeden" (Teutoburg Forest, Germany). The forest district "Grosser Freeden" is situated in the northwestern Teutoburg Forest (Lower Saxony, northwest Germany) and became a strict forest reserve in 1972. We investigate how the deciduous forest stands in this reserve evolved after the cessation of timber harvesting and which biotic and abiotic factors led to the current status. In this context, forest history is considered as well. In former times, the investigation area was owned by the prince-bishopric of Osnabruck. Following owners were the Kingdom of Hanover, Prussia and since 1945 the federal state of Lower Saxony. Nowadays, one-storied Fagus sylvatica L. stands are growing on the southern slope that is covered with thick, loess-derived soils. The steep northern slope is dominated by two-storied Fagus sylvatica stands with several secondary tree species, the Rendzina soil is quite shallow (Tab. 1). Even 33 years after the last harvesting operations, it is still apparent how the stands had once been managed. However, tree species that are not site-adapted or less competitive (e.g. Picea abies (L.) Karst. or Ulmus glabra Huds.) are increasingly being replaced by the competitive Fagus sylvatica. Hence, during the observation period (1971-2004), tree-layer diversity decreased, while tree-layer Volume increased (Tab. 2, 4, 5, Fig. 2, 3). Besides high tree mortality due to competition, a considerable dieback of Ulmus glabra occurred, which can be explained by the Dutch elm disease temporary drought stress. Regarding Acer pseudoplatanus L., the analysis of a real time series reveals that this tree species grows faster than Fagus sylvatica in early stages (Fig. 4). The difference of rate of growth between these two tree species decreases with increasing age, until finally Fagus sylvatica overgrows Acer pseudoplatanus. In contrast, Fraxinus excelsior L. grows better than Fagus sylvatica. This trend increases during the last two decades of the observation period and can be explained by a combination of site factors and stand history (Tab. 3). The volume of decaying wood amounts in average to 34 m(3) per hectare (Tab. 6). Due to the protection of natural processes the abundance of decaying wood will increase in the future. Especially in homogeneous and one-storied Fagus sylvatica stands a considerable number of trees will die back in the next decades. In 2004, we found almost no tree regeneration due to Fagus sylvatica competition and very high Population density of fallow deer (Dama dama L.). Since 2005, fallow deer numbers have been reduced by intensified hunting. As a consequence, the forest can develop in a more natural way henceforth. For future stand structure and tree species composition, especially disturbances such as wind throw will be crucial
A novel BCR-JAK2 fusion gene is the result of a translocation (9;22)(p24;q11) in a case of CML.
No full textSEQUENTIAL FISH-ANALYSES OF CIRCULATING CD34+-CELLS IN MDS - A SUITABLE METHOD FOR CYTOGENETIC MONITORING UNDER S-AZACYTIDINE OR LENALIDOMIDE
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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