Impact Type: Deposition of pollutant
The River jelly lichen (Collema dichotomum) is, as its name suggests, an aquatic lichen. It is found growing on permently submerged rocks in fast flowing intermediate and upland streams (Purvis et al. 1992, Biodiversity Steering Group 1995). Its decline has been attributed to the eutrophication of streams, where it is replaced by algal species, as well as by siltation, acidification and water abstraction (Biodiversity Steering Group 1995). Although eutrophication of surface waters is in many locations largely affected by agricultural run-off, in other areas atmospheric deposition may play a contributory role.
There is no published research on the impact of pollution on this UK BAP species.
|Critical Load/ Level|
No comparable habitat with established critical load estimate available