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Habitat selection of nine songbird species (Sylviidae, Prunellidae, Emberizidae, Fringillidae, Laniidae) in a semi-open transitional landscape (wood/meadow ecotone) is assessed and compared by a quantitative approach over a period of three years. The structural diversity and heterogeneity of this landscape allows a common occurrence to bird species that are spatially segregated in other habitats. On the one hand habitat selection, which in this study is defined by the choice of vegetation structures at the microhabitat level, is regarded as the confrontation of the single bird individuals with their environment and on the other hand as a common trait of subpopulations. The process of habitat selection is only real at the level of the individual. Drawing against this background, a model for the quantification of habitat selection is introduced, making possible an objective analysis of both individual and average habitat selection (not explaining the process itself, however, that leads to the observed habitat selection). The influence of several structural features, mainly regarding the shape of vegetational subunits, on the dispersion of the birds on the plots is analyzed by means of quantitative methods (factor analysis, cluster analysis, discriminant analysis). Preferences and avoidances, constancy in time and space and the degree of selectivity of the specific choice of vegetational structures are discussed in detail for each bird species. There is quantitative evidence that along with increasing abstraction from the individual in the form of spatially increasing data aggregation, the specific distinctness of habitat preferences as a common trait increases. This happens, however, at the expense of information about the variability of the individual selective behaviour. Therefore the flexibility of a bird species would be underrated cosiderably, confining habitat selection to its meaning as an integrating trait of populations. Habitat selection is a dynamic process. It is shown that the structural offer in a landscape strongly influences the result of the species" habitat selection. The availability of vegetational structures on a plot determines the quantitative structural framework, which may be more or less quantitatively modified by the single species. Nevertheless, the structural offer is reflected clearly in the selected structural portions of the bird species. Therefore opportunism and selectivity in the form of structural preferences and avoidances in habitat selection have to be interpreted against the background of the quantitative composition of the vegetational structures that a landscape offers to the birds.
The increase in recreational leisure during the last century and the increase in the individual mobility since the sixties have induced growing travel activities as well as a growing demand for recreation in a natural environment. Politically the demand for recreational leisure is regarded as a fundamental part of human life and is legally embedded as inherent goal of nature resorts besides nature conservation. Following new pedagogic principles man should get familiar with the environment in order protect nature in the long-run. Taking the bicycle concept of the nature resort Saar-Hunsrück with special emphasis on the St. Wendel country as an example the bicycle tourism which fulfils the principles of sustainability is analysed with regard to the acceptance by the tourists. Scenic and historical attractions of the area are deliberately taken into account in the design of the bicycle routes. By analysing the results of a survey it is the objective to work out applicable results for the design of routes and systems of orientation. Moreover it is the objective of a special survey on mountain bikers to answer the question on how this extreme type of biking could be incorporated in the supply of recreational activities of the nature resort and whether it can contribute to a growing environmental sensitivity.
The spatio-temporal changes of rangelands in the European Mediterranean are analysed with remote sensing and GIS-based methods, referring to an example of two mountain ranges in central Crete, Greece. The focus is to monitor and assess land degradation and its potential correlation with ecological and socio-economic boundary conditions. Particular attention is paid to the unique European Mediterranean setting and the Greek integration within the European Union. After a geometric correction of the satellite data, a radiometric pre-processing chain is employed to calculate reflectance values via a DEM-based atmospheric correction. The computation of pixel-wise soil and vegetation fractions is based on a spectral unmixing approach. A subsequent time-series analysis reveals spatially explicit trends, mean vegetation cover and phenological variability. Results do not only exhibit significant differences between the two test sites, but also within the respective regions. In both mountain ranges there extended areas with degrading vegetation patterns are revealed. However, along the Southern Cretan coast those processes are bound to a much lower base level of vegetation cover. Beyond trends and mean vegetation abundance, the phenological variability is another important figure which is employed to characterise plant communities from space. Moreover, a satellite-based map of soil development proves the correspondence between soil and vegetation degradation processes. Vegetation cover and change are then analysed with regard to aspect, slope, elevation and geological substrate to allow for a comparison of degradation processes and natural boundary conditions. In a second step, the analyses are extended to find interrelationships with socio-economic determinants. Based on these results the degradation risk for the grazing habitats of central Crete is assessed in differentiated ways. We neither encounter the scenario of irreversible degraded rangelands, nor a cultural landscape in an equilibrium under intense human influence.
Im Mittelpunkt der Arbeit steht die Frage nach der Darstellung Chinas in ausgewählten Geographieschulbüchern (Lehrbücher, Zusatzmaterialien und Schulatlanten) der Bundesrepublik Deutschland, der Deutschen Demokratischen Republik und der Republik Österreich. Ziel dieser Schulbuchanalyse ist es, die Chinadarstellungen zu erfassen und auf ihre inhaltliche Qualität und Gegenwartsbezogenheit zu überprüfen. Alle Schulbücher werden auf ihre sachliche Richtigkeit, Vollständigkeit und Angemessenheit, sowie nach Vorurteilen und Stereotypen untersucht. Dabei werden bestimmte Vorurteilsstrukturen (Pittoresken, Exotismen) und stereotype Deutungs- und Darstellungsmuster aufgedeckt, nationale Sichtweisen hervorgehoben und im Hinblick auf das Postulat der Völkerverständigung interpretiert. Der Hauptteil der Arbeit besteht aus einer zweistufigen Schulbuchanalyse, die sich in eine differenzierte quantitative und qualitative Inhaltsanalyse gliedert. Ein detailliertes Kategoriensystem bildet die Grundlage der Analyse. Anhand der thematischen Kategorien erhält der Leser die Möglichkeit, bestimmte Aussagen und Ergebnisse der Analyse nachzuprüfen und nachzuvollziehen und sich zudem wissenschaftlich fundierte Erkenntnisse über die einzelnen Themengebiete zu erschließen. Die Vernachlässigung bestimmter Themen zeigt sich in mehreren Schulbüchern, wobei insbesondere ein qualitativer Wandel in der Behandlung physisch- und anthropogeographischer Themen zu beobachten ist.
"Ökosystemare Aspekte von Wildtiernutzungsstrategien auf der Südhalbkugel" Die stark anwachsende Bevölkerung und z. T. nicht nachhaltig organisierte bzw. falsche Landnutzungsstrategien sind unter Armutsbedingungen die stärkste Bedrohung für endemitenreiche Ökosysteme. Fehlende Ökosystem- und Artenkenntnisse, unterentwickeltes Verständnis für utilitaristische Ansätze, die sich das Motiv der Existenzsicherung der Menschen in den ländlichen Regionen zu Nutze machen oder fehlende Einsichten in unterschiedliche Kulturen erschweren jedoch bisher die Umsetzung von "wise use" Kooperationsmodellen zwischen "Natur" und "Mensch" zum beiderseitigen Nutzen. Vorliegende Arbeit zeigt, dass nicht nur einzelne Arten, sondern ebenso die ökosystemare Diversität ein Differenzierungspotential für Nutzungs- und Vermarktungsstrategien besitzen. Aufbauend auf einer interdisziplinären Analyse werden in einem zweiten Arbeitsschritt die ökologischen, ökonomischen und soziokulturellen Auswirkungen unterschiedlicher Wildtiernutzungsstrategien aufgezeigt und belegt, dass durch sie Chancen zur Sicherung der Wildtierbestände bei gleichzeitiger Senkung der ländlichen Armutsbedingungen gegeben sein können. Dabei spielt eine naturnahe Bewirtschaftung von Lebensräumen durch den sog. Jagdtourismus eine besondere Rolle. Bei entsprechenden Kontrollmechanismen besitzt gerade er auf marginalen Standorten ein bisher noch nicht genügend genutztes Entwicklungs- und Schutzpotential. Insbesondere in den Pufferzonen um bzw. zwischen den Nationalparks ist dadurch eine Neubewertung der Wildtiere als Ressource zu beobachten, die durch wirtschaftliche Interessen der lokalen Bevölkerung das Verständnis für eine Koexistenz mit den Wildtieren fördert. Die sorgfältigen Analysen belegen dabei, dass ökosystemgerechter Jagdtourismus bei einer ganzheitlichen Betrachtung die Kriterien einer nachhaltigen Bewirtschaftung von Naturressourcen und die Ansprüche einer Low Impact & High Profit-Strategie erfüllt. Jagdtourismus kann somit als Element des Ökotourismus verstanden werden.
Wastewater treatment is of great financial concern in many states of Germany. In the rural areas of the Saarland (German state at the border to Luxembourg and France) investments for wastewater treatments in the next years will mount up to 400 mio. €. Nevertheless, decision makers are still left with the question, if these investments result in an effective and sustainable water treatment. To answer this question, the ministry of environment, related authorities and the University of the Saarland (Geographical Institute) started a Project to investigate seven small headwater catchments with predominantly Triassic series of Muschelkalk. Aims of this study were the following: (i) the description of the spatial variability of water chemistry upstream and downstream of small villages (in these villages only mechanically treated waste water is discharged into the brooks), (ii) calculation of nutrient loads of differently managed catchments (predominantly woodland, meadows or fields) and (iii) the relative importance of non-point pollution sources to point pollution sources. Results indicated that spatial variability of nitrate concentration during base-flow conditions was quite similar in intensively used agricultural areas. Nitrogen fluxes were predominantly controlled hydrologically. The nitrogen load (kg N per ha) from non-point pollution sources amounts from 32.5 to 43 kg N / ha * a in intensively used agricultural areas. This load, forecast to one square-km, is equal to the N-load of 800 " 1000 population equivalents. Thus, non-point pollution sources are a major part of the overall nitrogen pollution in the rural areas. The results are important criterias for the sewage disposal plan of the Saarland (disposal plans are obligate according to German water law) and can serve as a first part of a river basin management according to the European Water Framework Directive. To lower non-point N-pollution changes in agricultural management practices are necessary.
Soil and water conservation are cross-sectional assignments. The respective objectives of the individual interest groups cause conflicts of use and lead to different assessments of the soil's potential. Necessary decisions and the practical implementation of soil and water conservation measures require the use of data. These data, which are both spatial and temporal, characterise past, present and, in the case of predictions, also future environmental conditions. The multitude of relevant data necessitates the use of geographic information systems as an instrument for successful resource management. With the use of problem-oriented case studies, it was possible to show that an improved understanding of the system is necessary for both optimisation of the site-specific resource management within the framework of Precision Farming and for the assessment of local to regional conflicts of use with regard to land usage and soil and water conservation. By changing the method, sufficient respective measures regarding documentation, prevention and risk assessment were able to be introduced and implemented. With the objective of practical implementation of a sustainable resource management, the possibilities of short- to long-term initiation of self-organised systems through the networking of available (geo-)information as well as the respective interest groups involved in the conflict of use formed the focal point of this investigation. The creation of networks linking agriculture, water extractors and nature conservation promotes necessary synergies and emergences, due to increased communication. Not the conveyance of knowledge alone, but rather new forms of understanding cause the interest groups involved to change their behaviour, thus facilitating efficient resource management for the interests of soil and water conservation.
Today obesity has been recognized as a disease. Evidence suggests that obesity often has Genetic, environmental, psychological and other factors. Growing evidence points to heredity as a strong determining factor of obesity. The characterization of uncoupling proteins (UCP) represents a major breakthrough of genetic factors towards understanding the molecular basis for energy expenditure and therefore likely to have important implication for the cause and treatment of human obesity. UCPs as mitochondrial anion carriers which creates a pathway that allows dissipation of the proton electrochemical gradient therefore which when deregulated are key risk factors in the development of obesity and other eating disorders. In order to better understand the roles of both UCP2 and UCP3 which considered as prime candidate genes involved in the pathogenesis of obesity, this study elucidate (1) Genomic organization: The human UCP2 (3) gene spans over 8.7 kb (7.5 kb) distributed on 8 (7) exons. Three UCP genes may have evolved from a common ancestor or are the result from gene duplication events. Two mRNA transcripts are generated from hUCP3 gene, the long and short form of hUCP3 is differing by the presence or absence of 37 amino acid residues at the C-terminus. (2) Mutational analysis revealed a mutation in exon 4 of hUCP2 resulting in the substitution of an alanine by a valine at codon 55 and an insertion polymorphism in exon 8 consisted of a 45 bp repeat located 150 bp downstream of the stop codon in the 3'-UTR. The allele frequencies of both polymorphisms were not significantly elevated in a subgroup of children characterized by low Resting Metabolic Rates (RMR). (3) Promoter Analysis showed that the promoter region of hUCP2 lacks a classical TATA or CAAT box. Functional characterization of hUCP2 promoter showed that minimal promoter activity was observed within 65 bp upstream of the transcriptional start site. 75 bp further upstream a strong cis-acting regulatory element was identified which significantly enhanced basal promoter activity. The regulation of human UCP2 gene expression involves complex interactions among positive and negative regulatory elements. the 5"-flanking region of the hUCP3 gene were characterized in which contains both TATA and CAAT boxes as well as consensus motifs for PPRE, TRE, CRE and muscle-specific MyoD and MEF2 sites. Functional characterization identified a cis-acting negative regulatory element between - 2983 and -982 while the region between -982 and -284 showed greatly increased basal promoter activity suggesting the presence of a strong enhancer element. Promoter activity was particularly enhanced in the murine skeletal muscle cell line C2C12 reflecting the tissue-selective expression pattern of UCP3.
In Ostafrika ist der Fußgängerverkehr die mit Abstand wichtigste Fortbewegungsart. Dies gilt für städtische und ländliche Gebiete! Tatsache ist aber, dass die Probleme der Fußgänger in der Planung nicht ausreichend berücksichtigt werden. Die Politiker richten ihre zentrale Aufmerksamkeit auf den motorisierten Individualverkehr und missachten somit die Bedürfnisse der Mehrheit der Bevölkerung. Diese Disparität kann im Zuge einer nachhaltigen Entwicklung reduziert werden. Der nicht-motorisierte sowie der öffentliche Verkehr müssen stärker gefördert werden, da der motorisierte Individualverkehr in Ostafrika auf lange Zeit der breiten Bevölkerungsschicht vorenthalten bleibt. Westliche Wohlstandsmodelle dürfen demnach nicht als Verkehrsvorbild dienen. Die Entwicklungszusammenarbeit ist aufgerufen, Projekte in den Bereichen des öffentlichen sowie des nicht-motorisierten Verkehrs gezielt zu fördern. Nur so kann eine Transportplanung erfolgen, die ökologisch nachhaltig, sozial gerecht, ökonomisch effizient, politisch regulierend und investitionsfördernd ist. Durch gezielte Maßnahmen könnte eine Trendwende erreicht werden. Die Chancen für ein Umdenken in Form angepasster Verkehrspolitik sind gegeben. Wenn Industrieländer mit gutem Beispiel vorangehen, werden sich die Entwicklungsländer diesem Trend nicht verschließen können.