Wildflowers threatened by "safe" levels of nitrogen pollution
Wildflower season will be here before we know it and with it a new understanding of how we are affecting spring foliage. New science shows that even "safe" levels of nitrogen pollution -- pollution caused by the agricultural industry through nitrogen fertilizers -- have ill effects on wildflowers. While the fertilizer is a boon for farmers looking to boost crop yields, it has incredibly disastrous effects in other ecosystems, most noticeable in the gulf where agricultural run-off has triggered massive marine dead zones. And on land, wildflowers are also suffering a blow.
The Ecologist reports that a new paper written by Dr Richard Payne and Professor Nancy Dise, of Manchester Metropolitan University, and published in Proceedings of the National Academy of Sciences looks at 100 plant species in 153 grassland sites across Europe and examines their reactions to nitrogen deposition.
The scientists found that many species, particularly wildflowers such as creeping buttercup, harebell, yarrow, and autumn hawkbit, were much less abundant in areas with high nitrogen levels, such as central Britain, the Netherlands, northern Germany and Brittany. But particularly surprising was the discovery that many species declined at very low levels of pollution, often below the legally-recognised ‘safe’ level.
The findings show that even relatively "clean sites" far away from the source of pollution are still negatively affected, with a reduced abundance of some plant species. And this is no small issue. According to The Ecologist, "The scale of the problem is huge. It has been estimated nitrogen pollution costs the countries of the European Union alone up to €320 billion a year- but progress in tackling it has been limited... Nitrogen fertilizers are essential to feeding the world’s population but we can try to reduce the amount we use and the amount we lose into the environment."
While more attention is paid to the marine ecosystems impacted by nitrogen pollution, the study shows that an equal amount needs to be paid to the damages caused by the pollution to ecosystems on land -- from tropical rainforests to wildflower fields.