Austria ́s smallest nationalpark is known for its high diversity in flora and vegetation. This is... more Austria ́s smallest nationalpark is known for its high diversity in flora and vegetation. This is due to specific ecological conditions in the narrow inserted valley of the Thaya-river. With the forests, meadows and meadowfallows as well as the forest-free dry grasslands the most important terrestrial habitats of the Thayatal National Park could be documented with respect to their plant communities in the period from 2000 to 2006.In doing so, a knowledge gap existing for the Austrian section of this important nature area was closed, after the Czech Podyjí National Park had already been thoroughly investigated starting from 1989. The complete field survey of all meadows and meadow-fallows as well as all forest-free dry grasslands was accomplished after previous aerial photo interpretation. In a second phase, the investigation of the expanded forests was based on a stratified random sample. After classifying the whole nationalpark by means on geodata, representing its high lithologica...
Numbers indicate the relative importance (frequency of applications). Shaded squares show the ind... more Numbers indicate the relative importance (frequency of applications). Shaded squares show the index groups considered in this special issue. Large regional (e.g., Nordic, Mediterranean, continental, etc,) and global scales are not considered in this special issue.
The application of landscape patch shape complexity as a predictor of vascular plant and bryophyt... more The application of landscape patch shape complexity as a predictor of vascular plant and bryophyte species richness is analysed. Several common complexity indices (shape index, fractal dimension, comparison to the area of the minimum bounding rectangle) are tested for their predictive power for plant species richness. One new robust measure for shape complexity is presented which overcomes some disadvantages of common complexity measures applied to high resolution analysis of agricultural landscapes based on aerial photographs. The new index is based on the number of shape characterising points along a polygon's boundary. This new measure shows promising predictive capabilities for species richness of vascular plants and bryophytes (correlation coefficient: 0.85 for vascular plants, 0.74 for bryophytes).
We assessed the relationships between site size, habitat quality, landscape factors (fragmentatio... more We assessed the relationships between site size, habitat quality, landscape factors (fragmentation, landscape diversity) and species richness in communities of Collembola in 50 small dry grassland habitat patches in an agricultural landscape of eastern Austria. Grasslands in that region were once widespread and extensive, but have become increasingly fragmented and isolated. We hypothesized that dry grassland springtails species richness is significantly correlated with site variables (soil properties, habitat quality) and that the size of grassland sites is positively correlated with species richness. We used pitfall traps in 50 dry grasslands in differently structured agricultural landscapes and tested total abundance and three species richness measures: (1) the number of dry grassland specialist species; (2) total number of dry grassland species and (3) overall species richness. In the multivariate correlation models, we found that all species richness measures were significantly related to the plant species richness, a shape parameter of the sites, soil properties such as humus, temperature, sand and gravel content and the landscape variable reflecting isolation (distance to the nearest large dry grassland area). This landscape variable indicates that neighbouring grasslands are influencing the species richness of the sites. This may be a result of passive wind dispersal across the landscape or historic connection of the small sites with much larger dry grasslands. The size of the site did not show any significant correlation with total, dry grassland specialist, dry grassland generalist or generalist species richness. The small size of Collembola might explain these findings, because they have high population densities even in small patches.
The spatial patterns of vascular plant diversity in cultivated landscapes can be seen as the resu... more The spatial patterns of vascular plant diversity in cultivated landscapes can be seen as the result of different land-use systems which interfere with the given natural conditions. The degree to which human impact can explain these biodiversity patterns differs widely between different landscapes. For the case of Austriaa small but very heterogeneous countrythe correlation between land management, landscape structure and vascular plant diversity has been studied systematically in a nationwide survey, carried out during the last four years. In the course of this investigation, field data on vegetation and patch attributes have been collected in about 200 sample landscapes, following a stratified random sampling design. Using GIS and multivariate statistics, twelve landscape types could be detected which are characterised by a distinct spatial configuration of landscape elements. For these so-called FUNLANDs or functional landscape types it could be shown, that the relationship between "environmental factors", such as anthropogenic disturbance, wetness, successional stage on one hand, and diversity features like species richness and abundance of vegetation types on the other, clearly reflects an overall gradient. This gradient can be described as "hemerobiotic state" of a given landscape. The results of GIS-based quantification of landscape structure show a weak correlation between the investigated biodiversity features and most of the landscape attributes. Anthropogenic disturbance is the only attribute for which a strong negative correlation to the diversity patterns of vascular plants could be shown.
Satellite image segmentation with the aim to detect spatial units having an ecological meaning ha... more Satellite image segmentation with the aim to detect spatial units having an ecological meaning has become an important field in methodological research in modern landscape ecology. Within the theoretical framework, elaborated in, a landscape can be defined as ...
Innovation the European Journal of Social Science Research, Sep 1, 2011
This article may be used for research, teaching, and private study purposes. Any substantial or s... more This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.
In order to develop BiodiversityKnowledge, a Network of Knowledge working at the European science... more In order to develop BiodiversityKnowledge, a Network of Knowledge working at the European science-policy interface for biodiversity and ecosystem services, we conducted three trial assessments. Their purpose was to test structure and processes of the knowledge synthesis function and to produce knowledge syntheses. The trial assessments covered conservation and management of kelp ecosystems, biological control of agricultural pests, and conservation and multifunctional management of floodplains. Following the BiodiversityKnowledge processes, we set up expert consultations, systematic reviews, and collaborative adaptive management procedures in collaboration with requesters, policy and decision-makers, stakeholders, and knowledge holders. Outputs included expert consultations, systematic review protocols, a group model and a policy brief. Important lessons learned were firstly that the scoping process, in which requesters and experts iteratively Communicated by Marie Vandewalle. This is part of the special issue on Networking Biodiversity Knowledge.
ABSTRACT Zusammenfassend läßt sich feststellen, daß sowohl die Landschaftsstruktur als auch die E... more ABSTRACT Zusammenfassend läßt sich feststellen, daß sowohl die Landschaftsstruktur als auch die Erarbeitung von Zeigerarten für menschlichen Eingriff in das Konzept der Pressure-, State- & Response-Indikatoren passen. Die Datenverfügbarkeit dieser Indikatorensets ist in Österreich dank des beschriebenen Forschungsschwerpunktes und der damit befaßten Projekte im Moment sehr günstig, es muß jedoch darauf hingewiesen werden, daß nur eine Fortführung dieser Beobachtungen und Messungen die Verwertbarkeit als Indikatoren langfristig garantiert.
Sustainable development of cultural landscapes has become an important policy issue in Austria. T... more Sustainable development of cultural landscapes has become an important policy issue in Austria. Therefore ecologists are confronted with the demand for indicators describing sustainibility of land use on different scales. The presented paper proposes the elaboration of an indicator set reflecting the spatial configuration of elements in landscapes-the so-called landscape structure. Refering to the outcomings of an interdisciplinary research project in different Austrian agricultural regions it can be shown that certain features of landscape structure are suitable to describe sustainable land-use systems on a scale of 1:10.000.
Dank Eine Studie dieses Umfanges wäre nicht möglich ohne die Mithilfe und Zusammenarbeit aller Te... more Dank Eine Studie dieses Umfanges wäre nicht möglich ohne die Mithilfe und Zusammenarbeit aller TeamkollegInnen. Allen Mitarbeitern und Mitarbeiterinnen des Departments für Naturschutzbiologie, Vegetations-und Landschaftsökologie sowie jenen, die durch Diskussionsbeiträge und Kritik zum Gelingen beigetragen haben, sei herzlich gedankt. Besonders sei Herrn Univ.-Prof. Mag. Dr. Georg Grabherr dafür gedankt, dass er einer solchen Arbeit, die auf nicht unumstrittene Weise Neuland betritt, soviel Verständnis entgegenbrachte und zu ständiger Diskussion bereit war. Den Kollegen Dr. Franz Michael Grünweis danken wir für zahlreiche Hinweise und Anregungen, Frau Mag. Andrea Stocker-Kiss für die in gewohnter Weise präzise und effizient durchgeführte Berichterstellung.
Verhandlungen der Zoologisch-Botanischen Gesellschaft in Wien. Zoologisch-Botanische Gesellschaft in Wien
Die Beweidung am Illmitzer Zicksee im "Nationalpark Neusiedler See-Seewinkel" wurde 1987 mit eine... more Die Beweidung am Illmitzer Zicksee im "Nationalpark Neusiedler See-Seewinkel" wurde 1987 mit einer Herde von Galloway-Rindern wieder begonnen, um die typische Hutweidelandschaft mit zahlreichen Rote-Liste-Arten langfristig zu erhalten. Der Schwerpunkt der 9jährigen Monitoringstudic lag in der Evaluierung der Auswirkungen der Weideeffekte auf die halophile Lackenrandvegetation und Trockenrasen. Durch das Monitoring konnte nachgewiesen werden, daß extensiv beweidete Trockenrasen durch den Biomasseentzug und die Entstehung zahlreicher Bestandslücken artenreicher sind als nicht beweidete. Darüber hinaus konnte die Beweidung erfolgreich eingesetzt werden, um Ackerund Weingartenbrachen wieder in Richtung Trockenrasen zu entwickeln. Von entscheidender Bedeutung für die Etablierung neuer Arten ist der Sameneintrag durch die Rinder (Verbreitung über Kuhfladen und Substrat zwischen den Hufen), der die Besiedelung der Flächen durch Trockenrasenarten deutlich beschleunigt. Die Ausbreitung von Problemarten wie Quecke (Elymus repens) oder Land-Reitgras (Calamagrostis epigeios) auf jungen Brachflächen wird deutlich reduziert. KORNER I., TRAXLER A. & WRBKA Th., 1999: Grazing as a management tool for dry grasslands in the "National Park Neusiedler See-Seewinkel". Over the last centuries, huge cattle herds traditionally kept in shifting grazingregimes influenced the ecosystems of the pannonic sand steppes and halophytic inland lakes of the "National Park Neusiedler See-Seewinkel". After grazing ceased in the mid-20 lh century a cattle herd of galloways was reintroduced in 1987 to preserve a typical pasturing landscape with its specialised organisms depending on grazing management. A nine-year-long monitoring project was set up to evaluate the grazing effects on the vegetation of halophytic plant communities and dry grasslands. Extensive grazing was found to result in a higher biodiversity of dry grassland species due to biomass reduction, slight disturbance, increased vegetation niches and enhanced seed dispersal. Particularly the improved seed dispersal due to diasporcs in cow-dung and hoofs has been recognised as a driving force in restoring dry grassland vegetation in vineyard-fallows. It was additionally observed that invasive species of these fallows such as Elymus repens and Calamagrostis epigeios were reduced by the direct grazing and trampling effect of the cows.
Austria ́s smallest nationalpark is known for its high diversity in flora and vegetation. This is... more Austria ́s smallest nationalpark is known for its high diversity in flora and vegetation. This is due to specific ecological conditions in the narrow inserted valley of the Thaya-river. With the forests, meadows and meadowfallows as well as the forest-free dry grasslands the most important terrestrial habitats of the Thayatal National Park could be documented with respect to their plant communities in the period from 2000 to 2006.In doing so, a knowledge gap existing for the Austrian section of this important nature area was closed, after the Czech Podyjí National Park had already been thoroughly investigated starting from 1989. The complete field survey of all meadows and meadow-fallows as well as all forest-free dry grasslands was accomplished after previous aerial photo interpretation. In a second phase, the investigation of the expanded forests was based on a stratified random sample. After classifying the whole nationalpark by means on geodata, representing its high lithologica...
Numbers indicate the relative importance (frequency of applications). Shaded squares show the ind... more Numbers indicate the relative importance (frequency of applications). Shaded squares show the index groups considered in this special issue. Large regional (e.g., Nordic, Mediterranean, continental, etc,) and global scales are not considered in this special issue.
The application of landscape patch shape complexity as a predictor of vascular plant and bryophyt... more The application of landscape patch shape complexity as a predictor of vascular plant and bryophyte species richness is analysed. Several common complexity indices (shape index, fractal dimension, comparison to the area of the minimum bounding rectangle) are tested for their predictive power for plant species richness. One new robust measure for shape complexity is presented which overcomes some disadvantages of common complexity measures applied to high resolution analysis of agricultural landscapes based on aerial photographs. The new index is based on the number of shape characterising points along a polygon's boundary. This new measure shows promising predictive capabilities for species richness of vascular plants and bryophytes (correlation coefficient: 0.85 for vascular plants, 0.74 for bryophytes).
We assessed the relationships between site size, habitat quality, landscape factors (fragmentatio... more We assessed the relationships between site size, habitat quality, landscape factors (fragmentation, landscape diversity) and species richness in communities of Collembola in 50 small dry grassland habitat patches in an agricultural landscape of eastern Austria. Grasslands in that region were once widespread and extensive, but have become increasingly fragmented and isolated. We hypothesized that dry grassland springtails species richness is significantly correlated with site variables (soil properties, habitat quality) and that the size of grassland sites is positively correlated with species richness. We used pitfall traps in 50 dry grasslands in differently structured agricultural landscapes and tested total abundance and three species richness measures: (1) the number of dry grassland specialist species; (2) total number of dry grassland species and (3) overall species richness. In the multivariate correlation models, we found that all species richness measures were significantly related to the plant species richness, a shape parameter of the sites, soil properties such as humus, temperature, sand and gravel content and the landscape variable reflecting isolation (distance to the nearest large dry grassland area). This landscape variable indicates that neighbouring grasslands are influencing the species richness of the sites. This may be a result of passive wind dispersal across the landscape or historic connection of the small sites with much larger dry grasslands. The size of the site did not show any significant correlation with total, dry grassland specialist, dry grassland generalist or generalist species richness. The small size of Collembola might explain these findings, because they have high population densities even in small patches.
The spatial patterns of vascular plant diversity in cultivated landscapes can be seen as the resu... more The spatial patterns of vascular plant diversity in cultivated landscapes can be seen as the result of different land-use systems which interfere with the given natural conditions. The degree to which human impact can explain these biodiversity patterns differs widely between different landscapes. For the case of Austriaa small but very heterogeneous countrythe correlation between land management, landscape structure and vascular plant diversity has been studied systematically in a nationwide survey, carried out during the last four years. In the course of this investigation, field data on vegetation and patch attributes have been collected in about 200 sample landscapes, following a stratified random sampling design. Using GIS and multivariate statistics, twelve landscape types could be detected which are characterised by a distinct spatial configuration of landscape elements. For these so-called FUNLANDs or functional landscape types it could be shown, that the relationship between "environmental factors", such as anthropogenic disturbance, wetness, successional stage on one hand, and diversity features like species richness and abundance of vegetation types on the other, clearly reflects an overall gradient. This gradient can be described as "hemerobiotic state" of a given landscape. The results of GIS-based quantification of landscape structure show a weak correlation between the investigated biodiversity features and most of the landscape attributes. Anthropogenic disturbance is the only attribute for which a strong negative correlation to the diversity patterns of vascular plants could be shown.
Satellite image segmentation with the aim to detect spatial units having an ecological meaning ha... more Satellite image segmentation with the aim to detect spatial units having an ecological meaning has become an important field in methodological research in modern landscape ecology. Within the theoretical framework, elaborated in, a landscape can be defined as ...
Innovation the European Journal of Social Science Research, Sep 1, 2011
This article may be used for research, teaching, and private study purposes. Any substantial or s... more This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.
In order to develop BiodiversityKnowledge, a Network of Knowledge working at the European science... more In order to develop BiodiversityKnowledge, a Network of Knowledge working at the European science-policy interface for biodiversity and ecosystem services, we conducted three trial assessments. Their purpose was to test structure and processes of the knowledge synthesis function and to produce knowledge syntheses. The trial assessments covered conservation and management of kelp ecosystems, biological control of agricultural pests, and conservation and multifunctional management of floodplains. Following the BiodiversityKnowledge processes, we set up expert consultations, systematic reviews, and collaborative adaptive management procedures in collaboration with requesters, policy and decision-makers, stakeholders, and knowledge holders. Outputs included expert consultations, systematic review protocols, a group model and a policy brief. Important lessons learned were firstly that the scoping process, in which requesters and experts iteratively Communicated by Marie Vandewalle. This is part of the special issue on Networking Biodiversity Knowledge.
ABSTRACT Zusammenfassend läßt sich feststellen, daß sowohl die Landschaftsstruktur als auch die E... more ABSTRACT Zusammenfassend läßt sich feststellen, daß sowohl die Landschaftsstruktur als auch die Erarbeitung von Zeigerarten für menschlichen Eingriff in das Konzept der Pressure-, State- & Response-Indikatoren passen. Die Datenverfügbarkeit dieser Indikatorensets ist in Österreich dank des beschriebenen Forschungsschwerpunktes und der damit befaßten Projekte im Moment sehr günstig, es muß jedoch darauf hingewiesen werden, daß nur eine Fortführung dieser Beobachtungen und Messungen die Verwertbarkeit als Indikatoren langfristig garantiert.
Sustainable development of cultural landscapes has become an important policy issue in Austria. T... more Sustainable development of cultural landscapes has become an important policy issue in Austria. Therefore ecologists are confronted with the demand for indicators describing sustainibility of land use on different scales. The presented paper proposes the elaboration of an indicator set reflecting the spatial configuration of elements in landscapes-the so-called landscape structure. Refering to the outcomings of an interdisciplinary research project in different Austrian agricultural regions it can be shown that certain features of landscape structure are suitable to describe sustainable land-use systems on a scale of 1:10.000.
Dank Eine Studie dieses Umfanges wäre nicht möglich ohne die Mithilfe und Zusammenarbeit aller Te... more Dank Eine Studie dieses Umfanges wäre nicht möglich ohne die Mithilfe und Zusammenarbeit aller TeamkollegInnen. Allen Mitarbeitern und Mitarbeiterinnen des Departments für Naturschutzbiologie, Vegetations-und Landschaftsökologie sowie jenen, die durch Diskussionsbeiträge und Kritik zum Gelingen beigetragen haben, sei herzlich gedankt. Besonders sei Herrn Univ.-Prof. Mag. Dr. Georg Grabherr dafür gedankt, dass er einer solchen Arbeit, die auf nicht unumstrittene Weise Neuland betritt, soviel Verständnis entgegenbrachte und zu ständiger Diskussion bereit war. Den Kollegen Dr. Franz Michael Grünweis danken wir für zahlreiche Hinweise und Anregungen, Frau Mag. Andrea Stocker-Kiss für die in gewohnter Weise präzise und effizient durchgeführte Berichterstellung.
Verhandlungen der Zoologisch-Botanischen Gesellschaft in Wien. Zoologisch-Botanische Gesellschaft in Wien
Die Beweidung am Illmitzer Zicksee im "Nationalpark Neusiedler See-Seewinkel" wurde 1987 mit eine... more Die Beweidung am Illmitzer Zicksee im "Nationalpark Neusiedler See-Seewinkel" wurde 1987 mit einer Herde von Galloway-Rindern wieder begonnen, um die typische Hutweidelandschaft mit zahlreichen Rote-Liste-Arten langfristig zu erhalten. Der Schwerpunkt der 9jährigen Monitoringstudic lag in der Evaluierung der Auswirkungen der Weideeffekte auf die halophile Lackenrandvegetation und Trockenrasen. Durch das Monitoring konnte nachgewiesen werden, daß extensiv beweidete Trockenrasen durch den Biomasseentzug und die Entstehung zahlreicher Bestandslücken artenreicher sind als nicht beweidete. Darüber hinaus konnte die Beweidung erfolgreich eingesetzt werden, um Ackerund Weingartenbrachen wieder in Richtung Trockenrasen zu entwickeln. Von entscheidender Bedeutung für die Etablierung neuer Arten ist der Sameneintrag durch die Rinder (Verbreitung über Kuhfladen und Substrat zwischen den Hufen), der die Besiedelung der Flächen durch Trockenrasenarten deutlich beschleunigt. Die Ausbreitung von Problemarten wie Quecke (Elymus repens) oder Land-Reitgras (Calamagrostis epigeios) auf jungen Brachflächen wird deutlich reduziert. KORNER I., TRAXLER A. & WRBKA Th., 1999: Grazing as a management tool for dry grasslands in the "National Park Neusiedler See-Seewinkel". Over the last centuries, huge cattle herds traditionally kept in shifting grazingregimes influenced the ecosystems of the pannonic sand steppes and halophytic inland lakes of the "National Park Neusiedler See-Seewinkel". After grazing ceased in the mid-20 lh century a cattle herd of galloways was reintroduced in 1987 to preserve a typical pasturing landscape with its specialised organisms depending on grazing management. A nine-year-long monitoring project was set up to evaluate the grazing effects on the vegetation of halophytic plant communities and dry grasslands. Extensive grazing was found to result in a higher biodiversity of dry grassland species due to biomass reduction, slight disturbance, increased vegetation niches and enhanced seed dispersal. Particularly the improved seed dispersal due to diasporcs in cow-dung and hoofs has been recognised as a driving force in restoring dry grassland vegetation in vineyard-fallows. It was additionally observed that invasive species of these fallows such as Elymus repens and Calamagrostis epigeios were reduced by the direct grazing and trampling effect of the cows.
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