Contribution of multi-source remote sensing data to predictive mapping of plant-indicator gradients within Swiss mire habitats

Remote-sensing plays an important role in wetland monitoring on the regional and global scale. In this study we assessed the potential of different optical sensors to map floristic indicator gradients across complex mire habitats at the stand level. We compared traditional CIR photographs from RC30 cameras with modern digital ADS40 data and SPOT5 satellite images as well as fine-scale topo-structure derived from LIDAR data. We derived about 70 spectral and 30 topo-structural variables and evaluated their ability to predict the mean ecological indicator values of the vegetation across a sample of 7 mire objects. The airborne images (RC30, ADS40) and the LIDAR data were found to have a high potential for use in vegetation mapping; they explained on average 50% of the variation in observed ecological indicator values. The RC30 data slightly outperformed the less optimally collected ADS40 data. The LIDAR topo-structural variables showed equal overall predictive power as the airborne images, but they performed clearly better in predicting soil moisture, soil dispersion and light. Combining both airborne images and topo-structural data improved the predictions of all indicator values considerably. The combined use of these data sources is therefore recommended for use in fine-scale monitoring of priority habitats in nature conservatio

Partial regularity at the first singular time for hypersurfaces evolving by mean curvature

ABSTRACT. In this paper, we consider smooth, properly immersed hypersurfaces evolving by mean curvature in some open subset of R n+1 on a time interval (0, t 0 ). We prove that p -integrability with p ≥ 2 for the second fundamental form of these hypersurfaces in some space-time region B R (y) × (0, t 0 ) implies that the H n+2−p -measure of the first singular set vanishes inside B R (y). For p = 2 and n = 2, this was established by Han and Sun. Our result furthermore generalizes previous work of Xu, Ye and Zhao and of Le and Sesum for p ≥ n + 2, in which case the singular set was shown to be empty. By a theorem of Ilmanen, our integrability condition is satisfied for p = 2 and n = 2 if the initial surface has finite genus. Thus, the first singular set has zero H 2 -measure in this case. This is the conclusion of Brakke's main regularity theorem for the special case of surfaces, but derived without having to impose the area continuity and unit density hypothesis. It follows from recent work of Head and of Huisken and Sinestrari that for the flow of closed, k -convex hypersurfaces, that is hypersurfaces whose sum of the smallest k principal curvatures is positive, our integrability criterion holds with exponent p = n + 3 − k − α for all small α > 0 as long as 1 ≤ k ≤ n − 1. Therefore, the first singular set of such solutions is at most (k − 1) -dimensional, which is an optimal estimate in view of some explicit examples

Partial regularity at the first singular time for hypersurfaces evolving by mean curvature

ABSTRACT. In this paper, we consider smooth, properly immersed hypersurfaces evolving by mean curvature in some open subset of R n+1 on a time interval (0, t 0 ). We prove that p -integrability with p ≥ 2 for the second fundamental form of these hypersurfaces in some space-time region B R (y) × (0, t 0 ) implies that the H n+2−p -measure of the first singular set vanishes inside B R (y). For p = 2 and n = 2, this was established by Han and Sun. Our result furthermore generalizes previous work of Xu, Ye and Zhao and of Le and Sesum for p ≥ n + 2, in which case the singular set was shown to be empty. By a theorem of Ilmanen, our integrability condition is satisfied for p = 2 and n = 2 if the initial surface has finite genus. Thus, the first singular set has zero H 2 -measure in this case. This is the conclusion of Brakke's main regularity theorem for the special case of surfaces, but derived without having to impose the area continuity and unit density hypothesis. It follows from recent work of Head and of Huisken and Sinestrari that for the flow of closed, k -convex hypersurfaces, that is hypersurfaces whose sum of the smallest k principal curvatures is positive, our integrability criterion holds with exponent p = n + 3 − k − α for all small α > 0 as long as 1 ≤ k ≤ n − 1. Therefore, the first singular set of such solutions is at most (k − 1) -dimensional, which is an optimal estimate in view of some explicit examples

04231 Abstracts Collection -- Scheduling in Computer and Manufacturing Systems

During 31.05.-04.06.04, the Dagstuhl Seminar 04231 "Scheduling in Computer and Manufacturing Systems" was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

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

Complex national sampling design for long-term monitoring of protected dry grasslands in Switzerland

We describe a probabilistic sampling design of circular permanent plots for the long-term monitoring of protected dry grasslands in Switzerland. The population under study is defined by the perimeter of a national inventory. The monitoring focus is on the species composition of the protected grassland vegetation and derived conservation values. Efficient trend estimations are required for the whole country and for some predefined target groups (six biogeographical regions and eleven vegetation types). The target groups are equally important regardless of their size. Consequently, intensified sampling of the less frequent groups is essential for sample efficiency. The prior information needed to draw a targeted sample is obtained from the sampling frame and external databases. The logistics and generalized delineation of the target population may pose further problems. Thus, investments in fieldwork and travel time should be well balanced by selecting a cluster sample. Second, any access problems in the field and non-target units in the sample should be compensated for by selecting reserve plots as they otherwise may considerably reduce the effective sample size. Finally, the design has to be flexible as the sampling frame may change over time and sampling intensity might have to be adjusted to redefined budgets or requirements. Likewise, the variables and biological items of interest may change. To fulfil all these constraints and to optimally use the available prior information, we propose a multi-stage self-weighted unequal probability sampling design. The design uses modern techniques such as: balanced sampling, spreading, stratified balancing, calibration, unequal probability sampling and power allocation. This sampling design meets the numerous requirements of this study and provides a very efficient estimator

Soziologische Aspekte der Stadterneuerung. Teil 2: Entwicklung eines multidimensionalen Theorierahmens

In dem Beitrag wird ein Theorierahmen zur Erklärung von konflikthaften Prozessen teilräumlicher Stadterneuerung vorgestellt. Es wird die Entwicklung eines gesamtgesellschaftlichen orientierten, historisch-dialektisch argumentierenden Theorierahmens auf der Grundlage der drei Strukturmerkmale gesellschaftlicher Entwicklung: soziale Ungleichheit, Ungleichzeitigkeit der Entwicklung und Gewalt skizziert. In ersten Ansätzen wird die entsprechende theoretische Aufarbeitung der Hintergründe und Ergebnisse für eine durchgeführte Auftragsstudie - Planung und Bau des Europäischen Patentamtes in München - geleistet. Dadurch wird ein explizit theorie- und praxisgeleistetes Gegengewicht zu sozialökologischen Beschreibungsfiguren von stadt- und sozialstrukturellen Veränderungsverläufen gesetzt. (RW

Population trends of Rosalia alpina (L.) in Switzerland: a lasting turnaround?

Many species that depend on old trees and dead wood are suffering from habitat losses and intensive forest management. For the conspicuous cerambycid beetle Rosalia alpina, a relative sampling analysis combined with a distribution model showed a population decrease in Switzerland between 1900 and World War II. This negative trend can be ascribed to the abandonment of traditional management such as wooded pasture and to the expansion of high forest promoted by modern forestry. Since that period, the population of R. alpina, has been increasing and each single relict population of this species was maintained. These positive population trend can be explained by less intensive forest management and a shift from fuel-wood production to timber wood. Today, many more old beech trees and much more dead wood remain in Swiss forests than 50years ago. Consequently, the habitat conditions necessary for the development of the Rosalia longicorn have improved, especially on steep terrain in colline and submontane regions. However, it is still uncertain whether current population sizes can guarantee the survival of this species in the long term, especially as fuel-wood production is expected to become more intensive in Switzerland in future decades. The conservation of this species requires, therefore, the establishment of natural forest reserves and dead wood islands or the restoration of wooded pastures with scattered habitat trees. The Rosalia longicorn could then act as an umbrella species for other species that depend on old trees and dead woo