N deposition :: River jelly lichen

Latin name: 

Collema dichotomum

Impact Type: Deposition of pollutant

Key Concerns:

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.

Additional Comments:

There is no published research on the impact of pollution on this UK BAP species. 

Critical Load/level: 

Critical Load/ Level

No comparable habitat with established critical load estimate available

References: 

Church, J.M.; Coppins, B.J.; Gilbert, O.L.; James, P.; Stewart, N.F. 1996 Red Data Books of Britain and Ireland: lichens Britain 1
Group, Biodiversity Steering 1995 Biodiversity: the UK Steering Group report Action Plans 2
Purvis, O.W.; Coppins, B.J.; Hawksworth, D.L.; James, P.; Moore, D.M. 1992 Lichen Flora of Great Britain and Ireland 710

Species group: 

Pollutant: