Technical Yearbook 2024

JANUARY/FEBRUARY

Promotion of wild bees in South African and Austrian vineyards by plants with diverse floral traits By René Gaigher, Silvia Winter, Sophie Kratschmer & Temitope Kehinde The aim of this study was to gain a better understanding of how the plant community in vineyards could potentially be manipulated to improve bee diversity.

Global declines in pollinating insects Wild pollinating insects are declining in abundance and diversity worldwide. This is due to many interacting stressors such as climate change, pathogens, intensive farming practices with high levels of agrochemical inputs, and landscape transformation, which leads to a loss of pollinator habitats. 1 More than 75% of global food crops and more than 85% of wild flowering plant species rely on pollination provided by animals, mainly insects. Therefore, the decline in pollinators is of major concern for food security and the continued functioning of natural ecosystems. 3 Even though wine grapes do not depend on insect pollination, vineyards that are managed in an ecologically

sensitive way can provide pollinator-friendly habitats and, in doing so, support this important group of insects in farming landscapes. Factors that promote them include flowering plants in vineyard cover crops that provide essential food sources such as nectar and pollen, 4 reduced disturbance in vineyard inter-rows which promotes ground-nesting pollinators, 7 and semi-natural features in the landscape such as fallows and solitary trees which provide nesting habitats. The potential contribution of viticultural landscapes to pollinator conservation is significant because conservation in farmland is becoming an increasingly important part of global conservation strategies. 3

Hypothetical plant assemblages illustrate the difference between taxonomic and functional richness:

FIGURE 1 – ASSEMBLAGE A. High taxonomic richness (many different species) but low functional richness (they are all ecologically similar and belong to the same plant family).

FIGURE 1 – ASSEMBLAGE B. High taxonomic richness and high functional richness (a wide variety of ecological, morphological, and life-history traits among species).

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TECHNICAL YEARBOOK 2024