Oligotrophic Lakes in Ireland

Oligotrophic isoetid lake habitats (3110)

Oligotrophic isotid lake habitats (3110) are also referred to as Oligotrophic waters containing very few minerals of sandy plains (Littorelletalia uniflorae) under the EU Habitats Directive.

These lakes are dominated by isoetids and are typically found on sheltered, gently sloping shorelines, and are associated with peatland areas with soft, base-poor (pH < 6.5), nutrient poor waters on acid bedrock catchments (i.e. granite and/or sandstone). Ireland is a stronghold for this protected habitat

Currently conservation status = Bad

Acid oligotrophic lake habitats (3160)

Acid oligotrophic lake habitats (3160) are also referred to as Natural dystrophic lakes and ponds under the EU Habitats Directive.

These lakes are species poor with brown waters and are dominated by aquatic Sphagnum (moss) and the Order Utricularietalia. They are typically located in Atlantic and upland blanket bogs and wet heath with low pHs (3-6). They are known to have a rich invertebrate diversity e.g. Odonata.

Currently conservation status = Inadequate

Photos: Derryneen, Co. Galway; Isoetes lacustris; Myriophyllum alterniflorum

Photo credit: Heather Lally & Cilian Roden