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1.
Sabine Augustin Jan Evers Hans-Peter Dietrich Johannes Eichhorn Thomas Haussmann Regina Icke Ansgar Isenberg Wolfgang Lux Monica Musio Hans Pretzsch Winfried Riek Thomas Rötzer Bernd Schultze Andreas Schulze Jörg Schröder Walter Seidling Nicole Wellbrock Klaus von Wilpert Barbara Wolff 《European Journal of Forest Research》2005,124(4):251-260
In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and
other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system
in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse
effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary
air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring
was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and
feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal
Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives
of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification
and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading
to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected
level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis
(crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative,
as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the
extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
相似文献
Sabine AugustinEmail: |
2.
Species composition of arbuscular mycorrhizal fungi in two mountain meadows with differing management types and levels of plant biodiversity 总被引:1,自引:0,他引:1
Boris Börstler Carsten Renker Ansgar Kahmen François Buscot 《Biology and Fertility of Soils》2006,42(4):286-298
Species composition of arbuscular mycorrhizal fungi (AMF) was analysed in two differently managed mountain grasslands in Thuringia
(Germany). Arbuscular mycorrhizal fungi were studied in the roots of 18 dominant plant species from a total of 56 (32%). Additionally,
spores of AMF were isolated from soil samples. Arbuscular mycorrhizal fungi species composition was analysed based on 96 sequences
of the internal transcribed spacer of the nuclear ribosomal DNA, 72 originated from mycorrhizal roots, and 24 originated from
AMF spores. Phylogenetic analyses revealed a total of 19 AMF species representing all genera of the Glomeromycota except Scutellospora and Pacispora. Despite a different farming intensity, resulting in remarkable differences concerning their plant species diversity (27
against 43 plant species), the diversity of AMF was found to be similar with 11 species on the intensively farmed meadow and
ten species on the extensively farmed one. Nevertheless, species composition between both sites was clearly different. It
thus seems likely that the AMF species composition, but not necessarily the species number, is related to above ground plant
biodiversity in the system under study. 相似文献
3.
Grimberg A Baur H Bochsler P Bühler F Burnett DS Hays CC Heber VS Jurewicz AJ Wieler R 《Science (New York, N.Y.)》2006,314(5802):1133-1135
Lunar soils have been thought to contain two solar noble gas components with distinct isotopic composition. One has been identified as implanted solar wind, the other as higher-energy solar particles. The latter was puzzling because its relative amounts were much too large compared with present-day fluxes, suggesting periodic, very high solar activity in the past. Here we show that the depth-dependent isotopic composition of neon in a metallic glass exposed on NASA's Genesis mission agrees with the expected depth profile for solar wind neon with uniform isotopic composition. Our results strongly indicate that no extra high-energy component is required and that the solar neon isotope composition of lunar samples can be explained as implantation-fractionated solar wind. 相似文献
4.
5.
Aschfalk A Laude S Denzin N 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(9-10):351-354
An indirect ELISA was developed as a possible tool to detect the seroprevalence of antibodies to Salmonella spp in semidomesticated reindeer. To cover a broad spectrum of serogroups a lipopolysaccharide mix of S. typhimurium and S. choleraesuis was used as antigen in this pilot study. Sera from 31 culture-negative reindeer with no clinical or historical evidence of salmonellosis were used as negative serum control. After immunisation with an inactivated S. typhimurium vaccine, pooled sera from 6 reindeer were used as positive serum control as no serum from naturally infected animals was available. A seroprevalence of 0.6% in 2000 clinically healthy, slaughter-reindeer from Norway was determined by using this ELISA. No more information on Salmonella in reindeer in Norway is known to the authors. This is the first ELISA established for indirect detection of Salmonella in reindeer. 相似文献
6.
Penka Tsonkova Christian B?hm Ansgar Quinkenstein Dirk Freese 《Agroforestry Systems》2012,85(1):133-152
In temperate Europe alley cropping systems which integrate strips of short rotation coppices into conventional agricultural fields (ACS) are receiving increasing attention. These systems can be used for crops and woody biomass production at the same time, enabling farmers to diversify the provision of market goods. Adding trees into the agricultural land creates various additional benefits for the farmer and society, also known as ecosystem services. However, tree-crop interactions in the temperate region have not been adequately substantiated which is identified as a drawback to the practical implementation of such systems. In order to bridge this gap, the current paper aims to present a comprehensive overview of selected ecosystem services provided by agroforestry with focus on ACS in the temperate region. The literature indicates that compared with conventional agriculture ACS have the potential to increase carbon sequestration, improve soil fertility and generally optimize the utilization of resources. Furthermore, due to their structural flexibility, ACS may help to regulate water quality, enhance biodiversity, and increase the overall productivity. ACS are shown as suitable land use systems especially for marginal sites. Based on the available data collected, we conclude that ACS are advantageous compared to conventional agriculture in many aspects, and therefore suggest that they should be implemented at a larger scale in temperate regions. 相似文献
7.
Johannes?EichhornEmail author Regina?Icke Ansgar?Isenberg Uwe?Paar Egbert?Sch?nfelder 《European Journal of Forest Research》2005,124(4):335-347
The evaluation uses the longest available time series for beech and oak defoliation in Germany. The data from Hesse, starting
from 1984, show a typical pattern: for the first 12 years, a continuous increase in defoliation was observed ranging from
an average value of 14% in 1984 to a peak value of 30%. This was followed by a subsequent decrease in the loss of foliage
accompanied by a high variability, until the last monitoring in 2003, where an average value of 25% defoliation was observed.
For both tree species, the years of trend reversal were identical. The same pattern was observed in the German federal states:
Rhineland-Palatinate, North Rhine-Westphalia, and Bavaria. The year of trend reversal was identical in Hesse and Rhineland-Palatinate.
In North Rhine-Westphalia, it occurred 1 year earlier and in Bavaria 3 years earlier. Whereas defoliation trends were clearly
demonstrated, tree mortality did not appear on a large scale. The sample trees were grouped into four discrete clusters according
to their annual defoliation values from 1984 to 2003. In 1996, the clusters represent 15, 25, 35, and 50% defoliation values.
Regarding beech in Hesse, there was no overlap in the defoliation curves observed among the different clusters. These four
clusters having different degrees of defoliation over the whole time span of 20 years were used for a further detailed statistical
analysis. For discrete variables like crown spacing and—in the case of beech—fruit bearing, mosaic plots were applied in order
to visualize relations of low dimensional contingency tables, with defoliation trends being used as the response variable.
The data show for beech a very clear relation between defoliation and age, relative crown spacing, stand composition, and
fruit bearing. Regarding oak, besides age and relative crown spacing, the years with significant appearance of biotic stress
factors—leaf eating insects—show a clear relation to trends of defoliation. The statistical model used in this study—logistic
regression—allows applying a multinomial response variable and a number of continuous or categorical explanatory variables.
With this approach, an iterative optimized selection of effect variables was used to test the relevance of different variables
on the defoliation pattern of the same four clusters mentioned above. For this, the variables were grouped in an iterative
process with five steps, starting with a few basic variables of tree and site information, and ending with a total of more
than 20 variables in the fifth step. The process selects first the variables which are of significance on the defoliation,
and calculates the possible errors in the grouping of the different trees to the four clusters. In this analysis of beech,
the basic tree and stand variables: age, relative crown spacing, stand composition and fruit bearing proved to be the most
relevant group of parameters, with the other variables explaining the variation of defoliation only to a minor extent. More
complex model levels do not change any basic selected variables; however, Cation Exchange Capacity (CEC), C/N-ratio, Al- and
Ca-proportion of CEC are additionally selected and give a hint of the relevance of soil conditions. Regarding beech, the errors
of the statistical model are lower compared to oak. 相似文献
8.
Serosurvey for antibodies against Salmonella species in free-ranging moose (Alces alces) from Norway
Aschfalk A Hundertmark KJ Bendiksen HR Arnemo JM Denzin N 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(9-10):417-420
An indirect ELISA was developed as a tool for surveillance of antibodies against Salmonella sp. in free-ranging moose (Alces alces) in Norway. Serum samples from 303 clinically healthy moose sampled between 1993-2000 were examined. Anti-Salmonella antibodies were detected in samples from 6 individuals (1.98%). This is the first evidence of Salmonella-seropositive free-ranging moose. Possible sources and transmission routes of Salmonella comprising environment, wildlife and man are discussed. 相似文献
9.
Wasmer C Lange A Van Melckebeke H Siemer AB Riek R Meier BH 《Science (New York, N.Y.)》2008,319(5869):1523-1526
Prion and nonprion forms of proteins are believed to differ solely in their three-dimensional structure, which is therefore of paramount importance for the prion function. However, no atomic-resolution structure of the fibrillar state that is likely infectious has been reported to date. We present a structural model based on solid-state nuclear magnetic resonance restraints for amyloid fibrils from the prion-forming domain (residues 218 to 289) of the HET-s protein from the filamentous fungus Podospora anserina. On the basis of 134 intra- and intermolecular experimental distance restraints, we find that HET-s(218-289) forms a left-handed beta solenoid, with each molecule forming two helical windings, a compact hydrophobic core, at least 23 hydrogen bonds, three salt bridges, and two asparagine ladders. The structure is likely to have broad implications for understanding the infectious amyloid state. 相似文献
10.
Human social interactions crucially depend on the ability to represent other agents' beliefs even when these contradict our own beliefs, leading to the potentially complex problem of simultaneously holding two conflicting representations in mind. Here, we show that adults and 7-month-olds automatically encode others' beliefs, and that, surprisingly, others' beliefs have similar effects as the participants' own beliefs. In a visual object detection task, participants' beliefs and the beliefs of an agent (whose beliefs were irrelevant to performing the task) both modulated adults' reaction times and infants' looking times. Moreover, the agent's beliefs influenced participants' behavior even after the agent had left the scene, suggesting that participants computed the agent's beliefs online and sustained them, possibly for future predictions about the agent's behavior. Hence, the mere presence of an agent automatically triggers powerful processes of belief computation that may be part of a "social sense" crucial to human societies. 相似文献