According to a new study, air pollution prevents bees from finding flowers due to the degradation of floral scents. This discovery has significant implications for both the natural environment and tourism. A research team comprising the UK Centre for Ecology & Hydrology (UKCEH) and the Universities of Birmingham, Reading, Surrey, and Southern Queensland found that ozone substantially alters the size and scent of floral odour plumes emitted by flowers. The study revealed that honeybees’ ability to recognize these scents is reduced by up to 90% from just a few meters away.
Ground-level ozone, which forms when nitrogen oxide emissions from vehicles and industrial processes react with volatile organic compounds from vegetation in the presence of sunlight, plays a crucial role in this phenomenon. Professor Christian Pfrang from the University of Birmingham, a collaborator on the research, emphasized, “Our study provides robust evidence that the changes due to ground-level ozone on floral scent cause pollinators to struggle to carry out their crucial role in the natural environment, also with implications for food security.”
The findings suggest that ozone is likely to have a negative impact on wildflower abundance and crop yields. International research has already established that ozone negatively affects food production by damaging plant growth. Dr. Ben Langford, an atmospheric scientist at UKCEH who led the study, highlighted, “Some 75% of our food crops and nearly 90% of wild flowering plants depend, to some extent, upon animal pollination, particularly by insects. Therefore, understanding what adversely affects pollination, and how, is essential to helping us preserve the critical services that we rely upon for the production of food, textiles, biofuels, and medicines.”
The researchers used a 30-meter wind tunnel at Surrey University to monitor how the size and shape of odour plumes changed in the presence of ozone. They found that ozone not only decreased the size of the odour plume but also substantially altered its scent as certain compounds reacted more quickly than others. Honeybees, trained to recognize the original odour blend, were then exposed to the ozone-modified odours. The study showed that towards the center of plumes, 52% of honeybees recognized an odour at 6 meters, decreasing to 38% at 12 meters. At the edge of plumes, which degraded more quickly, only 32% of honeybees recognized a flower from 6 meters away, and just a tenth of the insects did so from 12 meters away.
The research indicates that ozone could also affect insects’ other odour-controlled behaviors, such as attracting a mate. This has broader implications for biodiversity, which is a key attraction for ecotourism. The study was funded by the Natural Environment Research Council, part of UK Research and Innovation, and published in the journal Environmental Pollution.
Professor Pfrang concluded, “We know that air pollution has a detrimental effect on human health, biodiversity, and the climate, but now we can see how it prevents bees and other pollinating insects from carrying out their key job. This should act as a wake-up call to take action on air pollution and help safeguard food production and biodiversity for the future.”
For countries that rely on tourism, especially eco-tourism, the decline in bee populations and other pollinators can significantly impact the natural landscapes that attract visitors. Ensuring clean air and protecting pollinators is not only crucial for food security but also for maintaining the biodiversity that makes destinations attractive to tourists. This study underscores the urgent need for environmental policies that address air pollution to protect both ecological health and tourism industries.
