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{{OR/14/043}}
''Palustiella ''dominated vegetation (based on 27 samples) has loosely been divided into 2 main groups and 4 subgroups. The two main groups (1 and 2) are shown to differ generally in respect to dominanace of individual ''Palustriella ''species, attitude, site ‘openness’ and number of flowering plant species. The two groups also correlate well to NVC M38 and M37 communities respectively.

''Palustriella ''dominated spring vegetation is an interesting habitat due to its strong topographical and hydrogeological components, is generally not species rich (6–52 species) and has very few species of conservation concern although ''Blysmus compressus ''(not recorded during the present survey) is an associated species of conservation concern listed as vulnerable in the Red Data Book (Cheffings & Farrell, 2005<ref name="Cheffings 2005">CHEFFINGS, C M, and FARRELL L. 2005. The vascular plant red data list for Great Britain. JNCC.</ref>).
Microtopography is an important factor influencing the character and structure of ''Palustriella'' dominated springs.

The presence of tufa is not considered to be a contolling factor in the occurance of ''Palustriella ''dominated springs and NVC M37/M38 communities. It is noted that this could be problematic as it does not fit with the European Commission definition of the Annex I habitat ''H7220 Petrifying springs with tufa formation (Cratoneurion) ''as ''being ‘''springs with active formation of tufa’.

The sites were divided into Group 1 and Group 2 and the key defining features of each group are summarized in Table 115.

All but one of the sites surveyed were considered to be in favourable ecological condition and all of the sites were considered to be in good hydrological condition, the results are presented in Table 116.

<center>
{| class="wikitable"
|+ Table 115    Summary of key ecohydrolgoical divisions between Group 1 and Group 2
| ! scope="col" style="width: 150px;" |
| ! scope="col" style="width: 250px;" | '''Group 1'''
| ! scope="col" style="width: 250px;" | '''Group 2'''
|- style="vertical-align:top;"
| Key species
| Dominantly ''Palustriella falcata''
| Only ''Palustriella commutata''
|- style="vertical-align:top;"
| NVC Community
| M 38
| M 37
|- style="vertical-align:top;"
| Elevation
| Upland
| Lo wland
|- style="vertical-align:top;"
| Elevation range
| 275–690 ma OD
| 5–402 ma OD
|- style="vertical-align:top;"
| Average Elevation
| 426 ma OD
| 85 ma OD
|- style="vertical-align:top;"
| Vegetation: 
Total species 
Flowering plants* 
Small ''Carex'' species
| Often with ''Festuca ovina'' 
21–52 
11–27 
2–3
| Often with ''Festuca rubra'' 
5–20 
1–10 
0–2
|- style="vertical-align:top;"
| Flow
| Smaller flows (<0.1–0.5 l/s)
| ‘Larger’ flows (<0.1–1 l/s)
|- style="vertical-align:top;"
| Occurrence of tufa
| Less tufa — some sites with no tufa
| More tufa — often deposited in significant quantities under natural conditions
|- style="vertical-align:top;"
| Water chemistry
| Less base rich (as bicarbonate)?
| More base rich (as bicarbonate)?
|- style="vertical-align:top;"
| Water Quality
| Low nutrient levels
| higher nutrient levels
|- style="vertical-align:top;"
| Openness of site
| Open
| Typically not open (incl. woodland, cliffs and gorges)
|- style="vertical-align:top;"
| Land use
| Upland/common land
| Lowland agricultural
|- style="vertical-align:top;"
| Grazing pressure
| Significant
| Low or none (incl. Many vertical sites)
|- style="vertical-align:top;"
| Ecological Pressures
| 2 sites (Nant Peris 1 and 2) with invasive alien ''Epilobium brunescens''
| No pressures identified
|-
| Hydrological Pressures
| No pressures identified
| No pressures identified
|- style="vertical-align:top;"
| colspan="3" | ''* flowering plants (including club mosses, horsetails and true ferns)''
|}
</center>

<center>
{| class="wikitable"
|+ Table 116    Summary of ecological and hydrological status
| ! scope="col" style="width: 200px;" | '''Site'''
| ! scope="col" style="width: 100px;" | '''Tufa forming?'''
| ! scope="col" style="width: 150px;" | '''Qualify as habitat H7220'''
| ! scope="col" style="width: 100px;" | '''Ecological condition'''
| ! scope="col" style="width: 100px;" | '''Hydrological Status'''
| ! scope="col" style="width: 100px;" | '''Overall condition'''
|- style="vertical-align:top;"
| Foel Fawr Site 1
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Foel Fawr Site 2
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Foel Fawr: Foel Garnach
| v.small area
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Foel Fawr: Brest Rhiw
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Pont Clydach 1
| No
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Pont Clydach 2
| No
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Pont Clydach 3
| No
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Blaen Onneu
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Llyn y Fan Fach 1
| v.small on one plant
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Llyn y Fan Fach 2
|
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Cwm Clydach
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Waun Ddu/Craig y Cilau
| No
| Yes
| Favourable
| Good
| Favorable
|- style="vertical-align:top;"
| Tarren y Esgob
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Hen Allt Common
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Cors Erdderiniog 7A Pipe
| Yes
| NO — minimal size of ''Palustriella ''veg
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Cors Erdderiniog
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Cors Erdderiniog
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Cors Erdderiniog ''F''
| Yes
| NO — minimal size of ''Palustriella ''veg
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Fedw Fawr Beach 1
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Fedw Fawr Beach 2
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Fedw Fawr Beach 3
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Ddol Uchaf
| Yes
| NO — minimal size of ''Palustriella ''veg
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| McWalters Dingle 1
| Yes
| Yes
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| McWalters Dingle 2
| Yes
| NO — minimal size of ''Palustriella ''veg
| Favourable
| Good
| Favourable
|- style="vertical-align:top;"
| Nant Peris 1 and 2
| No
| Yes
| Unfavourable
| Good
| Unfavourable
|- style="vertical-align:top;"
| Nant Peris 3
| No
| Yes
| Favourable
| Good
| Favourable
|}
</center>
==References==
<References/>
[[Category:OR/14/043 Survey, characterisation and condition assessment of Palustriella dominated springs 'H7220 Petrifying springs with tufa formation (Cratoneurion)' in Wales | 28]]

OR/14/043 Conclusions - Revision history

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Ajhil at 14:59, 17 March 2016