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Biology subjects

Fornoff, F.

Publications and source records attributed to Fornoff, F..

3 recordsLinked to original sources

Multi-dimensionality of tree communities structure host-parasitoid networks and their phylogenetic composition

Environmental factors can influence ecological networks, but these effects are poorly understood in the realm of the phylogeny of host-parasitoid interactions. Especially, we lack a comprehensive understanding of the ways that biotic factors, including plant species richness, overall community phylogenetic and functional composition of consumers, and abiotic factors such as microclimate, determining host-parasitoid network structure and host-parasitoid community dynamics. To address this, we leveraged a five-year dataset of trap-nesting bees and wasps and their parasitoids collected in a highly-controlled, large-scale subtropical tree biodiversity experiment. We tested for effects of tree species richness, tree phylogenetic and functional diversity, and species and phylogenetic composition on species and phylogenetic diversity of both host and parasitoid communities and the composition of their interaction networks. We show that multiple components of tree diversity and canopy cover impacted both, species and phylogenetic composition of hosts and parasitoids. Generally, phylogenetic associations between hosts and parasitoids reflected non-randomly structured interactions between phylogenetic trees of hosts and parasitoids. Further, host-parasitoid network structure was influenced by tree species richness, tree phylogenetic diversity, and canopy cover. Our study indicates that the composition of higher trophic levels and corresponding interaction networks are determined by plant diversity and canopy cover especially via trophic links in species-rich ecosystems.

ecology↗

Plant-pollinator interactions in apple orchards from a production and conservation perspective

In an agricultural landscape, production and conservation ideally go hand in hand. In a win-win scenario, conservation measures provide support for biodiversity and crop production, mediated by pollination for example. Hedges and flower strips are conservation measures that support pollinating insects, such as wild bees and hoverflies. They can be beneficial for crop pollination, but also harmful by dragging away pollinators from crops if flowering simultaneously. Here, we studied plant-pollinator interactions from two different perspectives. First we look at the apple-flower/production perspective investigating whether plant-pollinator networks in apple orchards differ with adjacent flower strips and hedges compared to isolated orchards. With help of the Bayes factor, we investigated similarity and conclude that there are no differences between pollination networks with or without adjacent flower strips and hedges. Second, we look at the pollinator/conservation perspective and analyse the impact of hedges and flower strips on pollinators and their interactions with plants before and after the apple bloom in April. We show that apple pollinators use more flower resources in flower strips and hedges across the whole season compared to isolated orchards. In orchards with flower strips and hedges interactions are more constant over time. We conclude that flower strips and hedges are beneficial for conservation of apple pollinators without being harmful for apple flower pollination being crucial for production.

ecology↗

Tree species and genetic diversity increase productivity via functional diversity and trophic feedbacks

Addressing global biodiversity loss requires an expanded focus on multiple dimensions of biodiversity. While most studies have focused on the consequences of plant interspecific diversity, our mechanistic understanding of how the diversity within a given plant species (genetic diversity) affects plant productivity remains limited. Here, we use a tree species x genetic diversity experiment to disentangle the effects of species diversity and genetic diversity, and how they are related to tree functional diversity and trophic feedbacks. Tree species as well as genetic diversity increased tree productivity via increased tree functional diversity, reduced soil fungal diversity and marginally reduced herbivory. The effect of tree genetic diversity on productivity was partly different between tree species monocultures and mixtures: the functional diversity effect resulting from tree genetic diversity was only found in tree species monocultures, but the trophic feedbacks via herbivory were similar in species monocultures and mixtures. Given the complexity of interactions between tree species and genetic diversity, tree functional diversity and trophic feedbacks on productivity, we suggest that both tree species and genetic diversity should be considered in reforestation.

ecology↗