Description: Das Projekt "Die Rolle der Variabilitaet als Triebkraft der Evolution und Lebenserhaltungssysteme von der Molekuelebene bis zur Ebene der Landschaften" wird vom Umweltbundesamt gefördert und von Universität Basel, Biozentrum, Abteilung Mikrobiologie durchgeführt. Do habitat destruction and fragmentation lead to reduced biodiversity? Does reduced biodiversity negatively affect ecosystem functions? How do ecosystems respond to the rising level of CO2? Fragmentation reuces biodiversity: The first results of the fragmentation experiment (J. Joshi unpublished data) show that, as expected, the plant species number in the investigated grassland declines with a reduction in area. Several animal spedes declined within lass than 6 months after fragmentation. Similarly, the fertility of the characteristic grass species was significantly reduced, possibly due to inbreeding. These early results already cleady indicate that reduced biodiversity is a likely consequence of habitat fragmentation. CO2, biodiversity and ecosystem functions: Less than one year after the start of the experiment we found that CO2 assimilation and carbon gain decreased with reduced biodiversity, i.e. from ecosystems containing 31 plant species to those containing only live species (P. Leadley, unpublished data). Whereas for these productivity measures the responses were parallel in ambient and elevated CO2, the effects of reduced biodiversity became more pronounced under elevated CO2 for some other measures. Also, depending on the level of biodiversity, particular species and genotypes showed fitness gains or losses under elevated CO2, and in one case this could be traced back to changed interactions with symbiotic fungi in the soil (A. Birrer, I. Sanders and T. Steinger, unpublished date). The first results of this experiment provide evidence that reduced biodiversity can disturb ecosystem functions under natural situations, a scientific fact of which we were completely ignorant at the start of the study. Diagnosis and management suggestions: Our diagnosis of the problem is severe, because the series of events appears to trigger a vicious cycle of habitat change-reduced biodiversity-disturbed ecosystems-further habitat change-etc. that eventually may even disturb human culture. What therapy can we use to disrupt this vicious cycle before it is too late? No explicit goals of biodiversity management in pen-urban environments have been stated for Switzerland.
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Süßgräser ? Genotyp ? Habitatverlust ? Basel ? Kohlenstoff ? Mikrobiologie ? Blei ? Schweiz ? Grünland ? Habitat ? Kohlendioxid ? Pflanzenart ? Therapie ? Gelöster organischer Kohlenstoff ? Biodiversitätsverlust ? Ökosystemfunktion ? Artenbestand ? Assimilation ? Daten ? Evolution ? Fruchtbarkeit ? Management ? Monitoring ? Naturwissenschaft ? Studie ? Wirkungsanalyse ? Pilz ? Pflanze ? Tier ? Boden ? Ökosystemforschung ? Ökosystem ? Flora ? Klima ? Biodiversität ? Produktivität ? Landschaft ? Veranstaltungsorganisation ? Fauna ? Grasland ? Biotopisolation ? Inzucht ? Variabilitaet ?
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 1993-01-01 - 1995-12-31
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