Plantlife in association with a number of botanical and conservation organisations including the National Trust, RSPB and the Woodland Trust have today published an important report ‘We need to talk about nitrogen’. You can download it here. This is a quote from the report.
Amid the clamour about climate change and carbon emissions, another alarm bell, largely unheard, has been sounding for some time. Global pools of reactive nitrogen have been building in the atmosphere, soils and waters from the burning of fossil fuels and intensive farming. This excess of reactive nitrogen is now being deposited throughout the biosphere, significantly impacting our most precious semi-natural habitats, changing their plant communities and the very functions these ecosystems provide.
We need to talk about nitrogen deposition, to raise awareness of its causes and consequences, to agree on solutions, and to work together to integrate these solutions into policy and practice now.
It is a topic that I have written about before – see here. I have been surprised by how few people are aware of this issue. In my view nitrogen deposition especially in the uplands is one of the main factors involved with the changes in vegetation that have occurred over the past few decades. I am certain that nitrogen deposition is highly implicated in the rise of Purple Moor Grass (Molinia caerulea) in the uplands of the UK, including Dartmoor.
This map produced by the Centre for Ecology and Hydrology shows the extend of the problem in the UK. Nitrogen deposition is acidifying your soils and saturating them with fertiliser.
Some species of plant respond well to high nitrogen levels and grow vigorously e.g. Molinia, however the majority of plant species respond poorly, in some cases they die out and in others they are outcompeted.
I recommend you read the Plantlife report.