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Henrik Barmentlo

Henrik Barmentlo is our Institute of Environmental Sciences' nominee for the C.J. Kok Jury Award 2020.

About Henrik's research

When hearing ‘neonicotinoids’, people think of bees, which are widely known to suffer from this class of insecticides in several ways. But they are not the only ones. For instance, water fleas are also affected. This model organism is often tested in the laboratory, but how are they affected in real conditions?

Henrik Barmentlo connected traditional ecotoxicology with ecology. He investigated what impact the agricultural use of neonicotinoids has in the field, not only on organisms, but also on ecosystems, focusing on freshwater.

‘Thanks to our Living Lab, which consists of 36 ditches, and with the help of many students and volunteers, I could investigate what neonicotinoid insecticides do to nature. I showed how detrimental effects on organisms translate into shifts in biodiversity and loss of ecosystem functioning.’

As his study shows, neonicotinoids have more severe effects on natural freshwater systems than laboratory studies can reveal. Effects of the insecticides on water fleas were much stronger outside than in the laboratory. That is because in the field, animals must compete for food and avoid predation, leading to increased stress levels with serious consequences. Barmentlo also found that the presence of ‘neonics’ reduced the growth and survival of larvae of damselflies and other insects. The abundance of adult insects decreased, potentially leaving less food available for insectivorous bats, birds, and frogs. Other species, mainly water mites, filled the vacancies and floating algae proliferated as the number of algae-consuming animals decreased. This way, neonics eventually hamper important ecosystem functions such as organic matter degradation and water purification.

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