OR/14/043 Site description - Fedw Fawr Beach
| Farr, G, Graham, J, and Stratford, C. 2014. Survey, characterisation and condition assessment of Palustriella dominated springs 'H7220 Petrifying springs with tufa formation (Cratoneurion)' in Wales. British Geological Survey Internal Report, OR/14/043. |
Introduction
‘Fedw Fawr’ beach is the name of a section of shoreline in the eastern part of Anglesey (nr SH6049081944), near to ‘Fedw Fawr (SSSI). Car parking is available near the Fedw Fawr site and steps lead to the beach and the three sites that are included within this section. Tim Blackstock (ex CCW) and Dr Peter Jones (NRW) both provided on site discussion and helped with the location of sites. Actively forming tufa was identified at all three sites.
Geological and hydrogeological data
The coastal exposure along this area is dominated by sandstones of the lower Carboniferous Loggerheads Limestone formation, the limestone itself is not exposed at sea level along this section of the coast and occurs slightly higher up within the stratigraphic sequence, overlying the sandstones. Sites 1 and 2 (FF1 and FF2) are both examples of tufa deposition with Palustriella commutata on sandstone bedrock cliff faces. The overlying Carboniferous Loggerheads Limestone Formation is visible on the edge of the small gorge that runs down to the beach (above Site 3 FF3 nr SH6073581784) although access to the outcrop is difficult.
Although all three areas of tufa formation occur on or near to the sandstone units the source of the water is most likely to be primarily within the overlying Carboniferous Loggerheads Limestone Formation. There are several wells and springs marked on the Ordnance Survey map that drain from the limestone and flow towards the coast via a series of small drains, culminating in the small waterfall feature at Site 1 (Site FF1.1). Seepage between the sandstone bedding planes, via joints and fractures also offer pathways for water, as does seepage directly down the face of the cliff.
Walking eastwards the tufa deposits at Site FF2.1 occur closest to the beach almost adjacent to the high tide mark. The seepage of water on the cliff face can be traced back up to the top of the cliff, along a small runnel that terminates in a large damp area just below the road where there is a spring marked as a well on the Ordnance Survey map (SH60638181800). This spring is the primary source of water for Site 2 however more diffuse seepage and sea spray will also contribute to this coastal exposure.
Site FF3 is located on the westerly side of a small gorge or valley that runs down from the higher farm land to the beach (SH6073581784). The start of the site is identifiable by a small outflow of water onto the beach. There is a large area of tufa in a small wooded area on the cliff side where it has formed as a large block with definable steps and water seepage occurs across this tufa block. A broken field drain protrudes from the top of the wooded section, it is not working but is an indicator that the fields above were possibly wet enough to warrant drainage. Seepage along the break in slope is marked by very wet ground and an extensive area of Palustriella commutata. The contact with the overlying limestone can be seen about half the way up this gorge at the top of the cliff section.
All three sites are supplied by water that has most likely originated in the overlying Carboniferous Loggerheads Limestone Formation.
A water quality sample was taken at each site, pH ranged from 8.29–8.45, Nitrate 1.16–3.18 mg/l N with only low amounts of Phosphate (0.03–0.04 mg/l). The ions are all dominated by Calcium and Bicarbonate.
Land use and pressures
All three sites are located along a coastal section where access to walkers is the primary landuse. There are no grazing animals and no evidence of poaching. The area is dominantly agricultural although nutrient levels were not particularly elevated in any of the water quality samples. It is possible that some of the farms and more remote properties have both private water supplies and sewage treatment systems although there is nothing to suggest that these activities are having any form of negative impact on the supply of water to the sites.
© Ordnance Survey.
© BGS © Ordnance Survey.
Vegetation — spring Fedw Fawr Site 1
Dripping spring vegetation and seepages dominated by Palustriella commutata and forming a narrow band (c. 2-3m) along the base of coastal cliffs (often in an underhang situation). Other frequent species include Pellia endiviifolia, Conocephalum conicum, Leicolea turbinata and substantial tufa deposits have frequent cushions of Eucladium verticillatum and occasional Didymodon tophaceus. Where these rock faces are partly shaded, a small number of characteristic woodland species are present in small quantity and include Asplenium scolopendrium, Hedera helix, Geranium robertianum and locally Hypericum andosaemum.
| Agrostis stolonifera | O |
| Anera pinguis | O |
| Asplenium scolopendrium | F |
| Conocephalum conicum | F |
| Cratoneuron filicinum | O |
| Didymodon tophaceus | R |
| Eucladium verticillatum (spor.) | A |
| Festuca rubra | F |
| filamentous algae (Chlorophyta) | O |
| Fissidens adianthoides(spor.) | O |
| Fissidens taxifolius var. taxifolius | R (<1%) |
| Geranium robertianum | R |
| Hedera helix | O |
| Hypericum androsaemum | R (<1%) |
| Juncus effusus | R (<1%) |
| Jungermania atrovirens (non fertile) | R (<1%) |
| Leicolea turbinata (spor.) | F |
| Nostoc sp. | O |
| Palustriella commutata | D |
| Pellia endiviifolia | O |
| Riccardia multifida | R (<1%) |
| Rubus fruticosus agg. | R (<1%) |
Vegetation adjoining spring spring Fedw Fawr Site 1
The spring flows and seepages along the base of the coastal cliff produce a small stream channel below. Associated small waterfalls and open running water support emergents such as Apium nodiflorum, Nasturtium officinale s.l., Agrostis stolonifera, Samolus valerandi, occasional Epilobium hirsutum. Stands of Chysosoplenium oppositifolium and Hookeria lucens are often present at the base of small waterfalls where water seeps away into soil. Rocks within fast flowing water are dominated by Rhynchostegium riparioides with occasional Brachythecium rivulare.
| Agrostis stolonifera | R |
| Allium ursinum | O |
| Apium nodiflorum | R |
| Brachythecium rivulare | O |
| Chiloscyphus sp. (non fertle) | R |
| Chrysosplenium oppositifolium | O |
| Conocephalum conicum | O |
| Cratoneuron filicinum | O |
| Dryopteris dilatata (seedling) | R |
| Epilobium hirsutum | R |
| Ficaria verna | O |
| Fissidens taxifolius var. taxifolius | F |
| Galium aparine | R |
| Hookeria lucens | R |
| Nasturtium officinale s.l. | O |
| Oxyrrhynchium hians | O |
| Pellia endiviifolia | O |
| Primula vulgaris | R |
| Ranunculus repens | O |
| Rhynchostegiella pumilla | O |
| Rhynchostegium riparioides | F |
| Samolus valerandi | R |
| Urtica dioica | R |
Outcropping acid rocks (a narrow band c. 1 m) along the base of coastal cliffs (often overhanging a lower band with calcareous seepages and tufa). A small number of calcifuge species are present including Calluna vulgaris, Potentilla erecta, Diplophyllum albicans and Dicranella heteromalla. Where there is seepage of water (acidic), cushions of Sphagnum subnitens have developed along with scattered plants of Succisa.
| Asplenium adiantum-nigrum | R |
| Bare rock | F |
| Calluna vulgaris | R |
| Dicranella heteromalla | O |
| Diplophyllum albicans | F |
| Hieracium sp. | R |
| Mnium hornum | O |
| Pellia cf epiphylla (non fertile) | R |
| Potentilla erecta | R |
| Sphagnum subnitens | R |
| Succisa pratensis | R |
Tall Bracken dominated vegetation (to 1 m height) on acidic soil on the top of coastal cliffs. A small number of typically calcifuge woodland species occur beneith the Bracken fronds (always in small quantity) and include Mnium hornum, Lonicera periclymenum, Dicranum majus, Plagiochila asplenioides and Silene dioica. Locally, flushing occurs with dominant stands of Hookeria lucens.
| Brachypodium sylvaticum | R |
| Dicranum majus | R |
| Hookeria lucens (acid flush) | O |
| Hypnum jutlandicum | O |
| Kindbergia praelonga | O |
| Lonicera periclymenum | R |
| Lophocolea bidentata | R |
| Mnium hornum | O< |
| Plagiochila asplenioides | R |
| Pteridium aquilinum | D |
| Rubus fruticosus agg. | O |
| Salix cinerea s.l. | R |
| Silene dioica | O |
| Thuidium tamariscinum | O |
Vegetation (spring) for Fedw Fawr Beach Site 2
Dripping vegetation and seepages dominated by Palustriella commutata and forming a narrow band (c. 2–3 m) along the base of coastal cliffs. Other frequent species include Pellia endiviifolia, Conocephalum conicum, Crataneron filicinum and substantial tufa deposits have frequent cushions of Eucladium vericillatum, Didymodon tophaceus. Where the rock face is partly shaded, a small number of characteristic woodland species are present in small quantity and include Asplenium scolopendrium, Hedera helix, Ficaria verna. Larger seepages (with more or less constantly dripping water) support emergents such as Apium nodiflorum, Nasturtium officinale s.l., Agrostis stolonifera, Samolus valerandi and large stands of Chysosoplenium oppositifolium are often present at their base.
| Agrostis stolonifera | O |
| Anera pinguis | O |
| Apium nodiflorum | R |
| Asplenium scolopendrium | F |
| Chrysosplenium oppositifolium | R |
| Conocephalum conicum | F |
| Cratoneuron filicinum | O |
| Didymodon tophaceus | F |
| Eucladium verticillatum | O |
| Festuca rubra | F |
| Ficaria verna | R |
| filamentous algae (Chlorophyta) | F |
| Fissidens adianthoides | R |
| Fissidens taxifolius var. taxifolius | O |
| Hedera helix | R |
| Jungermania atrovirens (non fertile) | R (<1%) |
| Leicolea turbinata (spor.) | F |
| Nasturtium officinale s.l. | O |
| Palustriella commutata | D |
| Pellia endiviifolia | O |
| Samolus valerandi | R |
Vegetation (adjoining spring) for Fedw Fawr Beach Site 2
A small stream channel cutting deeply into coastal cliffs (with small falls in places) and continuing below to the sea. The open running water supports emergents such as Apium nodiflorum, Nasturtium officinale s.l. and regularly submerged rocks or tufa have stands of Rhynchostegium riparioides and occasional Brachythecium rivulare. Adjoining to the left of this small stream (at the base of the cliff and where the water seeps away into soil), a small area of marshy rush dominated vegetation has developed with Juncus acutiflorus, Juncus subnodulosus, Calliergonella cuspidata, Filipendula ulmaria, Epilobium hirsutum and Senecio cf aquaticus.
| Angelica sylvestris | R |
| Apium nodiflorum | F |
| Brachythecium rivulare | F |
| Calliergonella cuspidata | O |
| Carex cf acutiformis | R |
| Cirsium palustre | R |
| Conocephalum conicum | O |
| Cratoneuron filicinum | O |
| Epilobium hirsutum | O |
| Ficaria verna | R |
| Filipendula ulmaria | O |
| Fissidens taxifolius var. taxifolius | R |
| Hypericum tetrapterum | R |
| Juncus acutiflorus | F |
| Juncus subnodulosus | O |
| Nasturtium officinale s.l. | F |
| Pellia endiviifolia | O |
| Rhynchostegiella pumilla | R |
| Rhynchostegium riparioides | R |
| Rumex cf conglomeratus | R |
| Senecio cf aquaticus | R |
Tall bracken dominated vegetation (to 1 m height) on acidic soil on the top of coastal cliffs. A small number of woodland species occur beneath the Bracken fronds (always in small quantity) and include Hedera helix, Brachypodium sylvaticum, Rubus fruticosus.
| Brachypodium sylvaticum | R |
| Hedera helix | O |
| Kindbergia praelonga | O |
| Pteridium aquilinum | D |
| Rubus fruticosus agg. | O |
Tussocky maritime grassland dominated by Festuca rubra on rock outcrops and on the tops of boulders at the base of coastal cliffs. A small number of other species are present (Agrimonia eupatoiria, Dactylis glomerata, Plantago lanceolata, Centaurea nigra) and includes several characteristic maritime cliff species (Armeria maritima, Plantago maritima).
| Agrimonia eupatoria | O |
| Agrostis stolonifera | O |
| Armeria martima | R |
| Centaurea nigra | R |
| Cerastium fontanum | R |
| Dactylis glomerata | O |
| Festuca rubra | A |
| Hedera helix | R (<1%) |
| Plantago lanceolata | R |
| Plantago maritima | O |
Dripping coastal rocks and boulders (forming part of the sea shore) and associated with the outfall of a small stream channel which cuts deeply into coastal cliffs. These rocks are subject to saline ingress and sea spray which ‘checks’ the vegetation. The only species present is the alga Ulva intestinals which is locally dominant.
| Ulva intestinalis | F |
| Bare rock | A |
Vegetation (spring) for Fedw Fawr Beach Site 3
Dripping spring vegetation and seepages dominated by Palustriella commutata and forming a narrow band (c. 2–3 m) along coastal cliffs (within mature woodland). Other frequent species include Pellia endiviifolia, Conocephalum conicum, Crataneron filicinum and substantial tufa deposits have frequent cushions of Eucladium vericillatum and Didymodon tophaceus. These shaded rock and tufa blocks have a small number of characteristic woodland species (spread from the adjoining mature woodland) including Asplenium scolopendrium, Hedera helix, Fissidens taxifolius var. taxifolius and Geranium robertianum.
| Anera pinguis | F |
| Asplenium scolopendrium | A |
| Conocephalum conicum | A |
| Cratoneuron filicinum | O |
| Didymodon tophaceus | R |
| Eucladium verticillatum (spor.) | O |
| Festuca rubra | O |
| filamentous algae (Chlorophyta) | O |
| Fissidena taxifolius var. taxifolius | R (<1%) |
| Geranium robertianum | R |
| Hedera helix | O |
| Leicolea turbinata (per.) | O |
| Palustriella commutata | A |
| Pellia endiviifolia | O |
Vegetation (adjoining spring) for Beach Site 3
A small stream channel cutting deeply into coastal cliffs within mature woodland with a large fall of water (c. 5 m drop) in one place. The waterfall is heavily shaded by adjoining woodland and dominated by Conoceophalum conicum with occasional Crataneron filicinum and Chrysosplenium oppositifolium. The resulting stream below is more open and where the water seeps away into soil, marshy rush dominated vegetation has developed with Juncus acutiflorus, Juncus inflexus, Cirsium palustre, Lythrum salicaria, Epilobium hirsutum and locally dominant stands of Equisetum telmateia.
| Agrostis stolonifera | O |
| Allium ursinum | O |
| Brachythecium rivulare | R |
| Carex cf acutiformis | R |
| Chrysosplenium oppositifolium | R |
| Cirsium palustre | R |
| Conocephalum conicum | A |
| Cratoneuron filicinum | O |
| Epilobium hirsutum | O |
| Equisetum telmateia | O |
| Eupatorium cannabinum | R |
| Filipendula ulmaria | O |
| Fissidens taxifolius var. taxifolius | O |
| Juncus acutiflorus | R |
| Juncus inflexus | R |
| Lythrum salicaria | R |
| Pellia endiviifolia | O |
| Rhynchostegium riparioides | F |
A open soil slipped area to the left of a spring on a steep slope of a coastal cliff. The open soil is clay-rich, calcareous and mostly dominated by a small number of bryophytes including Leicolea turbinata, Aneura pinguis, Dicranella varia and Didymodon fallax.
| Leicolea turbinata (per.) | A |
| Anera pinguis | O |
| Barbula unguiculata (spor.) | R |
| Calamagrostis epigejos | O |
| Dicranella varia (spor.) | O |
| Didymodon fallax (spor.) | O |
| Didymodon insulanus | R |
| Festuca rubra | O |
| Pellia endiviifolia | F |
| Senecio jacobaea | R |
| Tussilago farfara | R (<1%) |
Tall Bracken dominated vegetation (to 1 m height) with scattered Ulex europaea on acidic soil on the top of coastal cliffs. A small number of typically calcifuge woodland species occur beneith the Bracken fronds (always in small quantity) and includes Mnium hornum, Hyacinthoides non- scripta, Plagiochila asplenioides and Thuidium tamariscinum. Locally, flushing occurs with domaint stands of Hookeria lucens.
| Hedera helix | R |
| Hookeria lucens (acid flush) | R |
| Hyacinthoides non-scripta | R |
| Mnium hornum | R |
| Plagiochila asplenioides | R |
| Pteridium aquilinum | D |
| Rubus fruticosus agg. | O |
| Thuidium tamariscinum | R |
| Ulex europaea | O |
Mature and open Ash-Field Maple woodland on steep slopes of coastal cliffs. A sparse calcareous ground flora is present dominated by Hedera helix, Dryopteris felix-mass, Geranium robertianum, Asplenium scolopendrium with Primula vulgaris and Rubus fruticosus. Epiphytes are very well developed with Fruallania dilatata, Metzgeria furcata, Ulota phyllantha, Parmelia perlata and Cololejeunea minutissima.
| Acer campestre | F |
| Acer psedoplatanus | R |
| Asplenium scolopendrium | O |
| Brachypodium sylvaticum | R |
| Cololejeunea minutissima (non fertile) | R |
| Corylus avellana | O |
| Dryopteris felix-mass | R |
| Fraxinus excelsior | O |
| Frullania dilatata | O |
| Geranium robertianum | R |
| Hedera helix | O |
| Hypnum cupressiforme | F |
| Kindbergia praelonga | R |
| Lophocolea bidentata | R |
| Metzgeria furcata | O |
| Orthotrichum affine | F |
| Oxyrrhynchium hians | O |
| Parmelia perlata | O |
| Plagiochila asplenioides | R |
| Primula vulgaris | R |
| Rhynchostegiella pumilla | R |
| Rubus fruticosus agg. | O |
| Salix cinerea s.l. | R (<1%) |
| Silene dioica | R |
| Ulota phyllantha | F |
Rock outcrops and boulders at the base of coastal cliffs (adjoining the sea shore). A single species Cochlearia officinalis s.l. was recorded.
| Cochlearea officinalis s.l. | R (<1%) |
| Bare rock | D |
Condition assessment
The overall assessment is that Fedw Fawr Beach (Sites 1–3) should be classified as being in favourable ecological and hydrogeological condition.
