Sundew plants, which live on insects stuck on their sticky traps and common across North America and Northern Europe, could turn vegetarian because of nitrogen pollution.
Sundew plants in Sweden are so full of nitrogen pollution that they are not showing much interest in eating bugs. Nitrogen pollution is giving the carnivorous plants so much nutrients that the plants do not feel like catching any more flies. According to an experiment that took place in Sweden, the northern part of the country is less polluted than the southern and central parts which have more industry.
"If there's plenty of nitrogen available to their roots, they don't eat as much" said leader researcher Dr. Jonathan Millett of Loughborough University. The study was funded by the National Environment Research Council. According to the study, the plants start to depend on nitrogen absorbed using their roots. This change of diet may have caused by color change. Sundew plants look much greener in highly polluted areas than those growing in nutrient-poor conditions as the latter have a typical red color that's used to attract insects. Ecologists can quickly gauge a nitrogen pollution area by looking at the color of sundew plants.
The study team found the sundew plants in southern Swedish bogs are greener and taking more nitrogen using their roots than the ones in northern bogs. "They're more full-up," Millett explained. "If you've got enough food in the fridge, you don't go to the shops to buy some more." According to the study, the plants in lightly polluted areas derived 57% of their nitrogen from insects, while in the heavily polluted areas, the plants dependence on nitrogen from insects was between 20%-30% only. It's not a good sign as the level of nitrogen in the heavily polluted areas is actually impairing the plants' ability to catch insects. And, in the long term, these plants could risk extinction as "the non-carnivorous plants can 'out-compete' them," Millett said.
Millett is planning to widen his study and planning to look in different areas including Britain. Things can be worse in Britain as it's mostly filled with more heavy industry comparing to Sweden.
