Description: Das Projekt "Lokale gegenueber regionaler Kontrolle der Artenvielfalt" wird vom Umweltbundesamt gefördert und von Eidgenössische Technische Hochschule Zürich (ETHZ), Institut für Terrestrische Ökologie ITOE durchgeführt. 1 Are determinants of characteristics of local populations local or historical (regional) processes? 2 What is effect of pathogens and parasites on local populations and communities of hosts? 3 Can molecular methods be used in population biology? A central problem in ecology is to explain the occurrance of diversity in natural species assemblages. Classical hypotheses investigate mechanisms of coexistence and are thus confined to strictly ecological phenomena. These forces act mainly on a local scale, and are thus referred to as 'local control'. A complementary view emphasizes the importance of meta populations, and historical, or phylogenetic, aspects in determining the species diversity of communities. These factors proceed on a much larger scale and are thus referred to as 'regional or historical control'. In order to study the relative importance of local and regional factors in determining the diversity of natural communities, bumblebees (Bombus Latreille and Psithyrus Lepeletier) occurring in dry meadows in the Swiss Jura mountains are used as a model system. A combination of classical ecological techniques and of modern, DNA based molecular methods, is used to study different aspects of community diversity. We present our research questions, introduce the methods, and briefly discuss our results. Complementary information: In a patchy environments, local (sub-)populations are found in suitable habitat localities within a region. Man-made changes that lead to habitat fragmentation accelerate such subdivision and can reduce the viability of populations and thus threaten biodiversity. It is therefore not only an important problem for ecological theory but also for applications in conservation biology to understand how such systems are controlled at the level of populations and communities. Work suggested here aims at distinguishing between the effects of local processes vs. the effect of regional processes on population characteristics and local species diversity. For this purpose, populations and species assemblages of Bombus spp. (Apoidea, Hymenoptera) occurring in dry meadows at various sites in the Jura mountains will be used as a model system. Species of Bombus differ considerably in their abundance and distribution and thus in the diversity of local species assemblages. In the ecological section of the project, variation in standard ecological characteristics, such as abundances, body sizes, or parasite load will be measured across sites in a region.
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Hummel ? Biene ? Hautflügler ? Jura ? Zürich ? DNA ? Genetik ? Ökologie ? Wiese ? Blei ? Schweiz ? Habitat ? Artenbestand ? Artenvielfalt ? Berg ? Monitoring ? Naturwissenschaft ? Ökosystemmodell ? Parasit ? Standortwahl ? Studie ? Phylogenese ? Biodiversität ? Fauna ? Gebirge ? Datenerhebung ? Population ? Krankheitserreger ? Bombus-Latreille ? history ? Diversität ? Biotopisolation ? Psithyrus-Lepeletier ?
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 1993-01-01 - 1995-12-31
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