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Cases and information on insects

Bees and other pollinators

Bees are one of the most important groups of insects that help pollinate wild plants and crops. But many bee species are declining, as are wild pollinators in general. This is due to several factors, but the largest decline can be traced to agricultural intensification in the 1960s with extensive cultivation of large areas of farmland, limiting small areas with natural vegetation (the so-called small biotopes), the use of large machines and agro-chemicals for pesticides and fertilizers. The application of nitrogen and pesticides reduces the availability of flowering plants that provide food for the bees, this applies to both weeds in the fields and adjacent natural areas. In addition, a wide range of insecticides are applied that also have toxic effects on beneficial insects such as pollinators.

In the section for Plant and Insect Ecology, we are studying the effect of nitrogen rich fertilizers and pesticides on pollinator food sources and the toxicity of pesticides on pollinators such as bumblebees. The toxicity of the insecticides is measured not only by immediate mortality (acute mortality within 48 hours, as done in standard tests), but also by long-term effects, such as reduced production of offspring, foraging and orientation ability.

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