Impact Type: Deposition of pollutant
Schistomatomma graphidioides is a lichen growing on parkland trees that appears to be threatened by nitrogen deposition. It is listed under the UK Biodiversity Action Plan. The key concern is fertilisation of parkland combined with intensive grazing or the application of organic manure to neighbouring agricultural land leading to elevated levels of nitrogen deposition from ammonia, as well as nitrogen oxides from roads.
Fertiliser dust and pesticide spray drift may also be factors in the decline of this species. No critical load has been defined for the protection of this species, a best estimate would be the critical load for deciduous woodland. Woodland edges and isolated trees tend to be higher than average levels of nitrogen deposition due to their proximity to agricultural land and aerodynamic effects.
|Critical Load/ Level|
No comparable habitat with established critical load estimate available