Fabian, Yvonne

[["dc.bibliographiccitation.firstpage","706"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Basic and Applied Ecology"],["dc.bibliographiccitation.lastpage","714"],["dc.bibliographiccitation.volume","13"],["dc.contributor.author","Bruggisser, Odile T."],["dc.contributor.author","Sandau, Nadine"],["dc.contributor.author","Blandenier, Gilles"],["dc.contributor.author","Fabian, Yvonne"],["dc.contributor.author","Kehrli, Patrik"],["dc.contributor.author","Aebi, Alex"],["dc.contributor.author","Naisbit, Russell E."],["dc.contributor.author","Bersier, Louis-Felix"],["dc.date.accessioned","2019-07-23T10:06:52Z"],["dc.date.available","2019-07-23T10:06:52Z"],["dc.date.issued","2012"],["dc.description.abstract","Species abundance in local communities is determined by bottom-up and top-down processes, which can act directly and indirectly on the focal species. Studies examining these effects simultaneously are rare. Here we explore the direct top-down and direct and indirect bottom-up forces regulating the abundance and predation success of an intermediate predator, the web- building spider Argiope bruennichi (Araneae: Araneidae). We manipulated plant diversity (2, 6, 12 or 20 sown species) in 9 wildflower strips in a region of intensive farmland. To identify the major factors regulating the distribution and abundance of A. bruennichi, we quantified three characteristics of vegetation (species diversity, composition and vegetation structure) as well as the spider’s prey community and natural enemies. The distribution and abundance of A. bruennichi was regulated by combined bottom-up and top-down processes as well as by direct and indirect interactions between trophic levels. Four main factors were identified: (1) the strong direct effect of vegetation structure, (2) the positive effect of plant species diversity, which affected spider abundance directly and indirectly through increased densities and size of flower-visiting prey species, (3) the positive or negative direct effects of different plant species, and (4) the strongly negative direct effect of predacious hornets. The advantage of taking a global approach to understand the regulation of species abundance is highlighted first by the quantification of the relative importance of factors, with a surprisingly strong effect of hornet predators, and second by the discovery of a direct effect of plant diversity, which raises intriguing questions about habitat selection by this spider."],["dc.identifier.doi","10.1016/j.baae.2012.10.001"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/61917"],["dc.language.iso","en"],["dc.relation.issn","1439-1791"],["dc.title","Direct and indirect bottom-up and top-down forces shape the abundance of the orb-web spider Argiope bruennichi"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","185"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Oecologia"],["dc.bibliographiccitation.lastpage","197"],["dc.bibliographiccitation.volume","189"],["dc.contributor.author","Sandau, Nadine"],["dc.contributor.author","Naisbit, Russell E."],["dc.contributor.author","Fabian, Yvonne"],["dc.contributor.author","Bruggisser, Odile T."],["dc.contributor.author","Kehrli, Patrik"],["dc.contributor.author","Aebi, Alexandre"],["dc.contributor.author","Rohr, Rudolf P."],["dc.contributor.author","Bersier, Louis-Felix"],["dc.date.accessioned","2019-07-23T10:04:04Z"],["dc.date.available","2019-07-23T10:04:04Z"],["dc.date.issued","2018"],["dc.description.abstract","Studies on biodiversity–ecosystem functioning (BEF) in highly controlled experiments often yield results incompatible with observations from natural systems: experimental results often reveal positive relationships between diversity and productivity, while for natural systems, zero or even negative relationships have been reported. The discrepancy may arise due to a limited or closed local species pool in experiments, while natural systems in meta-community contexts experience dynamic processes, i.e., colonization and extinctions. In our study, we analysed plant community properties and above-ground biomass within a semi-natural (i.e., not weeded) experiment in an agricultural landscape. Eleven replicates with four different diversity levels were created from a species pool of 20 wildflower species. We found an overall significant negative relationship between total diversity and productivity. This relationship likely resulted from invasion resistance: in plots sown with low species numbers, we observed colonization by low-performing species; colonization increased species richness but did not contribute substantially to productivity. Interestingly, when analysing the biomass of the sown and the colonizer species separately, we observed in both cases positive BEF relationships, while this relationship was negative for the whole system. A structural equation modelling approach revealed that higher biomass of the sown species was linked to higher species richness, while the positive BEF relationship of the colonizers was indirect and constrained by the sown species biomass. Our results suggest that, in semi-natural conditions common in extensive agroecosystems, the negative BEF relationship results from the interplay between local dominant species and colonization from the regional species pool by subordinate species."],["dc.identifier.doi","10.1007/s00442-018-4305-1"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/61915"],["dc.language.iso","en"],["dc.relation.issn","0029-8549"],["dc.relation.issn","1432-1939"],["dc.title","Understanding negative biodiversity–ecosystem functioning relationship in semi-natural wildflower strips"],["dc.type","journal_article"],["dc.type.internalPublication","no"],["dspace.entity.type","Publication"]]