Five-year changes in Swiss mire vegetation

To assess whether short-term changes in mire vegetation can be detected using the phytosociological approach, paired vegetation relevés from two surveys of 112 mire sites of Switzerland were assigned to phytosociological alliances through a numerical approach. About 30% of the plots were assigned to different alliances in the two surveys. These transitions were analysed based on species frequencies and interpreted ecologically using Landolt's indicator values. Transitions between different alliances were more frequently related to the appearance of new species rather than to the disappearance of species. Transitions from and to peat bog communities were frequent. Many plots with fen vegetation were transformed into other wetland types. Fen-grassland increased in abundance, mainly at the cost of small-sedge fens. To re-establish the function of the Swiss mires as peat producers, we recommend to raise the mean summer water table to a maximum depth of 10c

A phytosociological classification of Swiss mire vegetation

The mapping and monitoring of Swiss mires has so far relied on a classification system based on expert judgement, which was not supported by a quantitative vegetation analysis and which did not include all wetland vegetation types described in the country. Based on a spatially representative sample of 17,608 relevés from 112 Swiss mires, we address the following questions: (1) How abundant are wetland vegetation types (phytosociological alliances) in Swiss mires? (2) How are they distributed across the country--is there a regional pattern? (3) How clearly are they separated from each other? (4) How clear and reliable is their ecological interpretation? Using published wetland vegetation relevés and lists of diagnostic species for phytosociological units (associations and alliances) established by experts, we developed a numerical method for assigning relevés to units through the calculation of similarity indices. We applied this method to our sample of 17,608 relevés and estimated the total area covered by each vegetation type in Switzerland. We found that vegetation types not included in previous mapping were either rare in Switzerland (partly due to mire drainage) or poorly distinguished from other vegetation units. In an ordination, the Swiss mire vegetation formed a triangular gradient system with the Sphagnion medii, the Caricion davallianae and the Phragmition australis as extreme types. Phytosociological alliances were clearly separated in a subset of 2,265 relevés, which had a strong similarity to one particular association, but poorly separated across all relevés, of which many could not be unequivocally assigned to one association. However, ecological gradients were reflected equally well by the vegetation types in either case. Overall, phytosociological alliances distinguished until now proved suitable schemes to describe and interpret vegetation gradients. Nevertheless, we see the urgent need to establish a data base of Swiss wetland relevés for a more reliable definition of some vegetation unit

Landscape research in Switzerland: exploring space and place of a multi-ethnic society

Landscape research in Switzerland enjoys a high technological and intellectual standard. It is influenced by both region-independent stimuli (e.g. remote sensing, sociology, population biology or statistics), and stimuli that have a strong bounding to the regional context. Region-specific stimuli for Landscape Research in Switzerland are:- the highly heterogeneous topography of the mountains as prerequisite to develop and test landscape-related theories,- the contrasting individualistic lifestyles of a multi-ethnic society that generates contrasting notions towards landscapes and thus contrasting methods in landscape research,- the long tradition of environmental research, monitoring and education and the high public motivation to support landscape-related research, as well as- the direct democracy where Landscape Research finds an ideal experimental ground to test theories and research hypothesis about how public participation or diverse (public) value systems and stakeholder values affect landscapes.Landscape research in Switzerland developed under the institutional umbrella of several public universities and research Institutions, primarily in the disciplines of geography, botany, remote sensing, forestry, agriculture, ethnology and sociology.Modern landscape research in Switzerland is performed as basic as well as applied research. It is well-positioned in the following fields: (1) the interactions between stakeholder values (towards nature & landscapes) and landscape development, (2) integrating spatial aspects of population genetics with landscape ecology, (3) the impact of communications technology on landscape resources, exploring heterogeneity in ecosystem processes across landscapes, relating landscape indicators to ecological processes, landscape historical approaches, and communicating research to the public and to policy makers.Die Landschaftsforschung in der Schweiz ist sowohl technologisch als auch intellektuell hoch entwickelt. Sie wird geprägt von überregional wirkenden Forschungsstimuli, wie z.B. der Fernerkundung, der Soziologie, der Populationsbiologie oder der Statistik aber auch von Stimuli, die einen starken regionalen Bezug haben. Letztere sind:- die unterschiedliche Topographie des Gebirges als günstige Voraussetzung für das Entwickeln und Testen von landschaftsrelevanten Theorien,- die unterschiedlichen, individuellen Lebensstile einer multi-kulturellen Gesellschaft, welche bewirken, dass Landschaften ganz unterschiedlich wahrgenommen, und mit gegensätzlichen Methoden untersucht werden,- die langjährige Tradition im Erforschen und Beobachten der Umwelt sowie in der Umwelterziehung und die grosse Bereitschaft der Öffentlichkeit, landschaftsrelevante Forschung zu unterstützen, und- die direkte Demokratie, die für die Landschaftsforschung einen idealen experimentellen Raum zum Testen von Theorien und Hypothesen darstellt, z.B. darüber, wie die öffentliche Mitbeteiligung oder die unterschiedlichen Werthaltungen der Akteure die Landschaft beeinflussen.Die Landschaftsforschung in der Schweiz entwickelte sich an unterschiedlichen Institutionen und Universitäten, hauptsächlich in den Disziplinen Geographie, Botanik, Fernerkundung, Forst- und Agrarwissenschaften, Ethnologie und Soziologie.Die moderne Landschaftsforschung in der Schweiz versteht sich als grundlagen­ orientierte und angewandte Forschung. Sie ist auf folgenden Gebieten führend: (1) Analyse der Zusammenhänge zwischen den unterschiedlichen Werthaltungen der Akteure (gegenüber Natur & Landschaft) und der Landschaftsentwicklung, (2) Integration der räumlichen Aspekte der Populationsgenetik in die Landschaftsökologie, (3) Auswirkungen moderner Kommunikationstechnologien auf die Landschaft, (4) Analyse von ökologischen Prozessen in der realen Landschaft, (5) Indikatoren zur Beschreibung des Landschaftszustandes und ihre Verknüpfung mit ökologischen Prozessen, (6) Landschaftsgeschichte, und (7) Umsetzung von Wissen für die Öffentlichkeit und die Politik

Detecting successional changes in long-term empirical data from subalpine conifer forests

In many mountain regions, traditional agriculture and forestry are no longer economically viable and less intense land-use is becoming more and more widespread. Thus, the importance of understanding secondary succession in these abandoned systems increases. This study is based on a comparison of historic (1957) and present tree data (2001) from subalpine forest stands located in the Swiss National Park (SNP), where all management was stopped in 1914. The two data sets contain information on tree and sapling density as well as diameter distribution for all tree species present. Using time-series analyses, space for time substitution and multivariate methods (PCoA, minimum spanning tree analysis), we investigated if successional changes can be detected within the forest stands in the SNP. Our results showed that the stands studied are developing from a stage dominated by mountain pine (Pinus montana Miller) to a late successional stage dominated by Swiss stone pine (Pinus cembra L.) and European larch (Larix decidua Miller). This shift in species composition, which was observed in both the tree and sapling layer, was accompanied by a significant decrease in tree density (stems/ha). We also found that stand disturbances, such as fungal diseases, parasitic insects, ungulate browsing, windthrow or snow pressure, have not prevented succession from mountain pine to Swiss stone pine-larch communities. The minimum spanning tree analysis revealed that the sixteen observed 44-year-time-series cover at least 110 years of succession. This time frame is the shortest possible duration for a successional development starting from a 95 to 125-year-old mountain pine stand. The successional changes depicted in our study indicate how similar areas in the Central European Alps might develop in the near future when management cease

Combining high sensitivity cardiac troponin I and cardiac troponin T in the early diagnosis of acute myocardial infarction

-Combining two signals of cardiomyocyte injury, cardiac troponin I (cTnI) and T (cTnT), might overcome some individual pathophysiological and analytical limitations and thereby increase diagnostic accuracy for acute myocardial infarction (AMI) with a single blood draw. We aimed to evaluate the diagnostic performance of combinations of high sensitivity (hs) cTnI and hs-cTnT for the early diagnosis of AMI. -The diagnostic performance of combining hs-cTnI (Architect, Abbott) and hs-cTnT (Elecsys, Roche) concentrations (sum, product, ratio and a combination algorithm) obtained at the time of presentation was evaluated in a large multicenter diagnostic study of patients with suspected AMI. The optimal rule out and rule in thresholds were externally validated in a second large multicenter diagnostic study. The proportion of patients eligible for early rule out was compared with the ESC 0/1 and 0/3 hour algorithms. -Combining hs-cTnI and hs-cTnT concentrations did not consistently increase overall diagnostic accuracy as compared with the individual isoforms. However, the combination improved the proportion of patients meeting criteria for very early rule-out. With the ESC 2015 guideline recommended algorithms and cut-offs, the proportion meeting rule out criteria after the baseline blood sampling was limited (6-24%) and assay dependent. Application of optimized cut-off values using the sum (9 ng/L) and product (18 ng2/L2) of hs-cTnI and hs-cTnT concentrations led to an increase in the proportion ruled-out after a single blood draw to 34-41% in the original (sum: negative predictive value (NPV) 100% (95%CI: 99.5-100%); product: NPV 100% (95%CI: 99.5-100%) and in the validation cohort (sum: NPV 99.6% (95%CI: 99.0-99.9%); product: NPV 99.4% (95%CI: 98.8-99.8%). The use of a combination algorithm (hs-cTn

Evaluating the Predictive Power of Ordination Methods in Ecological Context

When striving for the ordination methods best predicting independently measured site factors, the following questions arise: does the optimal choice depend on the kind of biological community analysed? Are there different ordination methods needed to address different site factors? Simultaneously, I explore alternative similarity approaches of entire ordinations, as well as the role of the transformations applied to the scale used in measuring species performance. The combination of methods and data transformations results in 96 alternative solutions for any one data set. These are compared by a graphical display, that is, an ordination of ordinations. The goodness-of-fit of independently measured site factors is assessed by two alternative methods. The resulting 96 performance values serve as independent variables in trend surfaces overlaid to the ordination of ordinations. The results from two real-world data sets indicate that some ordination methods greatly vary with data transformation. Scores close to a binary scale perform best in almost all ordination methods. Methods that intrinsically constrain the range of species scores, such as principal components analysis based on correlation, correspondence analysis (including its detrended version), nonmetric multidimensional scaling, as well as principal coordinates analysis based on the Bray-Curtis distance, always figure among the most successful methods, irrespective of data used

Konzeption vegetationskundlicher Untersuchungen am Beispiel einer Gradientenanalyse

Jede vegetationskundliche Untersuchung besteht aus einer Reihe klar abgrenzbarer Untersuchungsschritte: Formulierung der Zielsetzung, Abgrenzung der Grundgesamtheit, Festlegung von Lage und Größe der Aufnahmeflächen, Wahl der Aufnahme- und der Analysemethode. Es wird vorgeschlagen, sich dabei an drei Referenzräumen zu orientieren: Dem physischen, dem standörtlichen und dem floristischen Raum. Bei den meisten Fragestellungen geht es darum, Strukturen und Prozesse des einen Raumes in den andern Räumen unverzerrt abzubilden. Ein konstruiertes Beispiel dient der Erläuterung des Prinzips. Anhand der Analyse eines Überganges von einem Zwischen- zu einem Flachmoor wird gezeigt, wie sich methodische Elemente zu einem leicht überblickbaren Konzept zusammenstellen lassen: Statt der bei Gradientenanalysen üblichen Transsektmethode wird ein systematisches Stichprobennetz verwendet. Die Vegetationsaufnahmen beruhen auf der Skala von BRAUN-BLANQUET. Zu jeder Aufnahme werden zahlreiche Standortparameter gemessen. Die Analyse erfolgt mit Hilfe verschiedener numerischer Methoden. Das Ergebnis zeigt ein klares Abbild der Gradientenstruktur mitsamt deren Variationsbreite.In Vegetation science, each investigation consists of a series of clearly defined methodological steps: Formulating the objective, defining the survey area, fixing the number and location of the relevés and choice of sampling method and algorithm for data analysis. It is suggested that three reference-spaces should be considered: the physical (real), the environmental and the floristic space. Many solutions require the undistorted projection of structure and processes of one space into the others. This principle is explained by use of simple, artificial data. Field data from a coenocline from peat bog to fen illustrate the application of such a concept. Instead of a simple transsect usually applied in gradient analysis, a systematic sampling-grid is used. The relevés are made with the BRAUN-BLANQUET scale. Numerous site factors are also measured within each plot. The data are analyzed by various numerical methods. The results reflect not only the gradient structure of vegetation and sites but also their variability