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In mechanized timber harvesting, it is common practice to build brush mats from logging residues on skid trails. Protective effects of brush mats against soil compaction are documented by several studies. On the other hand, a large quantity of nutrients is concentrated on the skid trail. Fully mechanized harvesting has been criticized frequently for this reallocation of nutrients. Is there really a risk of nutrient leaching below skid trails or imbalances? Are the nutrients redistributed through nutrient uptake by roots of adjacent trees? Effects of fully mechanized thinning on soil, water and nutrient balance were examined in a seventy years old spruce stand on a nutrient poor site in Bavaria. Sections of the trails were covered with brush mats, while other sections remained uncovered. For five replications, soil physical properties, soil chemistry, matter and water balances and the density of fine roots were measured in the middle of the trail, under the tire tracks, at the transition of trail and stand and inside the stand over a period of two years. Logging operation caused soil compaction. The macropore volume decreased and both hydraulic conductivity and air permeability were severely reduced. The nutrients were largely kept in the forest ecosystem. Results of the soil moisture monitoring indicate that, within the sections covered by a brush mat, tree roots extracted water from the soil between the tracks. Without cover, the trees scarcely extracted water from this area. Hence, building a brush mat can facilitate water availability and thus enable redistribution of nutrients.

In mechanized timber harvesting, it is common practice to build brush mats from logging residues on skid trails. Protective effects of brush mats against soil compaction are documented by several studies. On the other hand, a large quantity of nutrients is concentrated on the skid trail. Fully mechanized harvesting has been criticized frequently for this reallocation of nutrients. Is there really a risk of nutrient leaching below skid trails or imbalances? Are the nutrients redistributed through nutrient uptake by roots of adjacent trees? Effects of fully mechanized thinning on soil, water and nutrient balance were examined in a seventy years old spruce stand on a nutrient poor site in Bavaria. Sections of the trails were covered with brush mats, while other sections remained uncovered. For five replications, soil physical properties, soil chemistry, matter and water balances and the density of fine roots were measured in the middle of the trail, under the tire tracks, at the transition of trail and stand and inside the stand over a period of two years. Logging operation caused soil compaction. The macropore volume decreased and both hydraulic conductivity and air permeability were severely reduced. The nutrients were largely kept in the forest ecosystem. Results of the soil moisture monitoring indicate that, within the sections covered by a brush mat, tree roots extracted water from the soil between the tracks. Without cover, the trees scarcely extracted water from this area. Hence, building a brush mat can facilitate water availability and thus enable redistribution of nutrients.

The second Dagstuhl Seminar on emph{Computational Proteomics} took place from March 3rd to 7th, 2008 in Schloss Dagstuhl--Leibniz Center for Informatics. This highly international meeting brought together researchers from computer science and from proteomics to discuss the state of the art and future developments at the interface between experiment and theory. This interdisciplinary exchange covered a wide range of topics, from new experimental methods resulting in more complex data we will have to expect in the future to purely theoretical studies of what level of experimental accuracy is required in order to solve certain problems. A particular focus was also on the application side, where the participants discussed more complex experimental methodologies that are enabled by more sophisticated computational techniques. Quantitative aspects of protein expression analysis as well as posttranslational modifications in the context of disease development and diagnosis were discussed. The seminar sparked a number of new ideas and collaborations and has resulted in several joint grant applications and paper submissions. This paper describes the seminar topics, its goals and results. The executive summary is followed by the abstracts of the presentations given. Links to extended abstracts or full papers are provided, if available.