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Stuttgart, Germany

Hebel I.,University of Magallanes | Galleguillos C.,University of Magallanes | Jana R.,Instituto Antartico Chileno | Dacasa-Rudinger M.D.C.,Public Enterprise Sachsenforst
Revista Chilena de Historia Natural | Year: 2012

To commemorate one hundred years of Roald Amundsen's reaching the South Pole, we provide a summary of early explorations to Antarctica, in which botanists played an almost anonymous role. Based on multiple observations of vegetation they found and recorded, we review the knowledge available at the end of the nineteenth century to compare with contemporary scientific beliefs; connecting them with observations we have collected in field-work. Using the aerial photography from the end of the 1950s of sites we visited, it is noted that opportunities are arising for the understanding of colonization phenomena in areas where ice is retreating. Accounts of research on colonization of new ice-free areas are analyzed as well as how molecular genetics attempts to deduce the early settlements. Finally, an analysis of conservation in Antarctica is provided and its outlook discussed. © Sociedad de Biología de Chile. Source


Gradel A.,University of Gottingen | Gradel A.,Public Enterprise Sachsenforst | Hansch C.,TU Dresden | Ganbaatar B.,Mongolian Academy of science | And 3 more authors.
Dendrochronologia | Year: 2016

The mountain forest steppe and taiga in northern Mongolia have experienced a forest decline in area and quality since the end of the last century. Changes in land use, climate, fire frequency and pest occurrence are considered to be the main drivers of this vegetation shift and desertification. Because this region is the source for major rivers, is home to a unique flora and fauna and represents an important source of timber for Mongolia, the ability of different tree species to respond to these changes and regenerate is of increasing interest. Our contribution focuses on the climate-growth relationship of old and young birch trees from two valleys in the Mongolian province of Selenge Aimag.The research site Bugant, located in the Western Khentey Mountains, was the most important logging centre in Mongolia during socialist times. Today, the vegetation is dominated by succession forests of light taiga. The research site Altansumber, on the border of the Sant and Khushat soum, is dominated by light taiga and mountain forest steppe. Traditional nomads who depend on these forests for different reasons inhabit this area.Wood cores were sampled and chronologies of young and old birch trees at Bugant and Altansumber were created. Climate data were obtained from the Eroo station, which is known in the region for its long and reliable climate record. We analysed the climate-growth relationships of the chronologies from 1962 to 2009. At both sites and in both age classes, correlations with temperature were predominantly negative, particularly in April (Bugant, south- and east-facing slopes) and May (Altansumber, north-facing slopes). Precipitation of the late summer of the previous year (August/September) positively correlated with the growth of birch at Altansumber. We assume that the significant negative correlation between winter precipitation (December/January) and the growth of old birches at both sites is due to positive effects of snow cover on the survival rate of herbivorous insect populations. Our results indicate that during the early vegetation period, younger birch trees are more dependent on water availability than older ones. Negative pointer years were characterized by below-average precipitation during the current summer period and above-average spring temperatures. For the old trees, positive pointer years were characterized by above-average summer precipitation. We conclude that water availability is the most crucial factor for the growth of white birch in northern Mongolia. © 2016 Elsevier GmbH. Source


Petzold R.,Public Enterprise Sachsenforst | Butler-Manning D.,TU Dresden | Feldwisch N.,Ingenieurburo Feldwisch | Glaser T.,Office for Nature Conservation and Sustainable Land Use | And 3 more authors.
IForest | Year: 2014

Biomass from short rotation coppice (SRC) plantations has attracted widespread attention as a component of new sustainable energy concepts. Nevertheless, as yet the surface area of SRC plantations in Europe is relatively low compared to other biomass producing land-use systems. This is somewhat incomprehensible because it has been shown that SRC systems also offer distinct ecological benefits. Therefore, greater consideration of the related ecosystem services should be incorporated into land-use planning processes. Presented in this study is a conceptual framework for the integration of soil protection and nature conservation into the spatial prioritization of areas suitable for SRC. This approach includes the development of a site-specific yield model and the identification and classification of criteria and indicators for both soil protection and nature conservation. The basic concept for planning procedures was established and tested for the State of Saxony (Germany). Existing constraints were identified, and could be attributed mainly to the availability of adequate information at different spatial scales. The regional-scale study emphasized the considerable biomass potential of SRC and the related synergy effects for soil protection and nature conservation. Future work should focus on the local (district, farm) and catchment scale and attempt to integrate additional aspects such as hydrological ecosystem services and carbon sequestration. © SISEF. Source


Reim S.,Public Enterprise Sachsenforst | Proft A.,Green League Osterzgebirge e.V | Heinz S.,Green League Osterzgebirge e.V | Lochschmidt F.,Green League Osterzgebirge e.V | And 3 more authors.
Plant Genetic Resources: Characterisation and Utilisation | Year: 2015

Knowledge of pollen movement and frequency of interspecific hybridization in fragmented populations of rare species is a prerequisite for the implementation of conservation measures. In a large-scale study area (14,000 hectares) we analysed 297 Malus sylvestris trees with nine nuclear microsatellite markers. After open pollination of 564 offspring from 51 mother trees located in seven harvesting sites were investigated and genetic paternity analysis was performed. The paternal parent was identified for 213 offspring and the pollen dispersal distances between mother and pollen source were calculated. A large proportion of detected pollination events (42.4%) were observed within a radius of 50 m of the mother tree. The comparison of different tree densities indicated that with decreasing density the pollen dispersal distances increase. We observed pollination over long distances with a maximum of 10.7 km which is probably one of the reasons for a low spatial genetic structure within the M. sylvestris population and a stable genetic diversity in the offspring. Incorporating microsatellite data of 21 apple cultivars, a hybridization frequency of nearly 8% was determined. With decreasing tree density the number of hybridization events increased. Based on the results of our study an enhancement of the density of existing M. sylvestris populations is recommend to reduce the likelihood of hybridization. The production of young plants originated from seeds collected after open pollination is not advisable. Instead of that the seedlings for further reintroduction measures should be produced by controlled crossings in seed orchards to ensure ‘true type’ M. sylvestris individuals. Copyright © NIAB 2015 Source

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