Vegetation (Floating River Vegetation) - Office of Public Works

2.0 Description of the Special Areas of Conservation (SACs)
Special Areas of Conservation were legally established as nature refuges under Article 3 of
the Habitats Directive (Council Directive 92/43/EEC). The purpose of this legislation was to
develop an ecological network of Special Areas of Conservation across all European Union states
that collectively would be known as Natura 2000. In ecological terms there was a legal obligation
for each member state to identify, conserve and protect site(s) supporting rare or endangered plants,
animals and their habitats (section 1.2). Designation of Irish sites was performed in accordance with
the criteria set-out in Annex III of the Habitats Directive.
Some of the selection parameters used by the National Parks and Wildlife Services are:
•Importance of the site in terms of the habitats and species it supports
•Degree of representation of a habitat or habitats within a site to enhance, conserve and preserve
habitat diversity.
•Extent of isolation of the population (the more isolated the population the greater the genetic
divergence therefore greater genetic diversity).
•Degree of destruction if any that has occurred on the site
•Geographic distribution, frequency and distribution of habitats and / or protected and rare
species, presence of a priority habitat and the presence of a habitat or species important or
unique to Ireland (National Parks and Wildlife Services website).
Currently Ireland has proposed 420 sites as candidate Special Areas of Conservation to the
European Commission accounting for 10,000 square kilometres of land. The Special Areas of
Conservation include priority and important (but not priority) habitats along with protected plant
and animal species.
2.1 Description of the conservation aspects
This study focuses on Special Areas of Conservation with the designated habitat of
submerged or floating vegetation with low water level during summer and with typically
Ranunculion fluitantis and Callitrichio-Batrachion plant species or the bryophyte aquatic moss as a
conservation aspect. Flora associated with habitat 3260 includes Ranunculus saniculifolius,
Ranunculus trichophyllus, Ranunculus fluitans, Ranunculus penicillatus ssp. penicillatus,
Ranunculus penicillatus ssp. Pseudofluitantis, Ranunculus aquatilis, Myriophyllum spp.,
Callitriche spp., Sium erectum (or Berula erecta), Zannichellia palustris, Potamogeton spp., and
the moss Fontinalis antipyretica. Groenlandia densa (Opposite leaved pondweed) is also included
in the list. The flowering rush Butomus umbellatus may be present as part of the bank flora where
floating river vegetation has been identified. The occurrence of this species may be an indicator and
should be noted (ENUIS website).
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