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Individual study: Augmenting flower trait diversity in wildflower strips to optimise the conservation of arthropod functional groups for multiple agroecosystem services

Published source details

Balzan M.V., Bocci G. & Moonen A. (2014) Augmenting flower trait diversity in wildflower strips to optimise the conservation of arthropod functional groups for multiple agroecosystem services. Journal of Insect Conservation, 18, 713-728


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Pollination: Plant flowers Mediterranean Farmland

A replicated, controlled study in 2011 in an organic tomato field near Pisa, Italy, found that wild bees increased over time in some flower plots but decreased over time in others. Implementation options: In plots with three species from one plant family (Apiaceae), or six species from two plant families (Apiaceae and Fabaceae), numbers of bees increased over time (minimum: 0.3 bees/plot, 10–31 days after flowering; maximum: 3 bees/plot, 38–45 days after flowering). Similar numbers of bees were found in both of these flower-species mixtures (0.3–3 bees/plot). In plots with nine plant species (three Apiaceae, three Fabaceae, and three others), numbers of bees decreased over time (maximum: 3.7 bees/plot, on the first day of flowering; minimum: 0.2 bees/plot, 38 days after flowering). Methods: Four treatments were compared: three, six, or nine flower species/plot, and a control with no flowers. Five plots/treatment were sown with flower seeds on 6 and 21 June. Each flower plot (2 x 10 m) was next to a tomato plot (4 x 10 m). Bees on flowers were sampled with aspirators every 14 days after flowering began.

 

Pest regulation: Plant flowers Mediterranean Farmland

A replicated, controlled study in 2011 in an organic tomato field near Pisa, Italy (same study as (8)), found more natural enemies in flower plots than on bare ground. Plots with the most flower species had the fewest tomato pests but the most generalist pests, and plots with different numbers of flower species had similar numbers of natural enemies. Natural enemy numbers: More ground-dwelling predators were found in flower plots than on bare ground (carabid beetles/plot: 0–28.7 vs 0–1.2; staphylinid beetles/plot 0.5–7.4 vs 0–0.4; spiders/plot: 0.4–7.1 vs 0.2–1.5). Implementation options: Fewer tomato pests (sap-sucking bugs), but more generalist pests (Lygus sp. and Nezara viridula), were found on flowers in plots with nine flower species, compared to plots with three flower species (numbers of individuals not reported). Similar numbers of natural enemies were found on flowers in all plots (numbers of individuals not reported). On flowers, predatory beetles Hippodamia variegata and parasitic wasps increased over time (beetles: minimum: 0 individuals/plot, on the first day of flowering; maximum: 2.7 individuals/plot, 38 days after flowering; wasps: minimum: 0 individuals/plot, on the first day after flowering; maximum: 36.5 individuals/plot, 21 days after flowering), but formicid ants decreased over time (numbers of individuals not reported). On the ground, carabid beetles increased over time (minimum: 0 individuals/plot, nine days after flowering; maximum: 28.7 individuals/plot, 37 days after flowering), but staphylinid beetles and spiders did not. Methods: Four treatments were compared: three, six, or nine flower species/plot, and a control with no flowers. Five plots/treatment were sown with flower seeds on 6 and 21 June. Each flower plot (2 x 10 m) was next to a tomato plot (4 x 10 m). Ground-dwelling predators were sampled with pitfall traps every 7 days, and natural enemies on flowers were sampled with aspirators every 14 days, after flowering began.