Tŷ Ddewi / St David's Coast NVC Survey Report
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Tŷ Ddewi / St David’s Coast NVC Survey Report Steven Shepherd MCIEEM ADAS Report No 143 Date www.naturalresourceswales.gov.uk About Natural Resources Wales Natural Resources Wales is the organisation responsible for the work carried out by the three former organisations, the Countryside Council for Wales, Environment Agency Wales and Forestry Commission Wales. It is also responsible for some functions previously undertaken by Welsh Government. Our purpose is to ensure that the natural resources of Wales are sustainably maintained, used and enhanced, now and in the future. We work for the communities of Wales to protect people and their homes as much as possible from environmental incidents like flooding and pollution. We provide opportunities for people to learn, use and benefit from Wales' natural resources. We work to support Wales' economy by enabling the sustainable use of natural resources to support jobs and enterprise. We help businesses and developers to understand and consider environmental limits when they make important decisions. We work to maintain and improve the quality of the environment for everyone and we work towards making the environment and our natural resources more resilient to climate change and other pressures. www.naturalresourceswales.gov.uk Page 1 Evidence at Natural Resources Wales Natural Resources Wales is an evidence based organisation. We seek to ensure that our strategy, decisions, operations and advice to Welsh Government and others are underpinned by sound and quality-assured evidence. We recognise that it is critically important to have a good understanding of our changing environment. We will realise this vision by: Maintaining and developing the technical specialist skills of our staff; Securing our data and information; Having a well resourced proactive programme of evidence work; Continuing to review and add to our evidence to ensure it is fit for the challenges facing us; and Communicating our evidence in an open and transparent way. This Evidence Report series serves as a record of work carried out or commissioned by Natural Resources Wales. It also helps us to share and promote use of our evidence by others and develop future collaborations. However, the views and recommendations presented in this report are not necessarily those of NRW and should, therefore, not be attributed to NRW. www.naturalresourceswales.gov.uk Page 2 Report series: NRW Evidence Report Report number: 143 Publication date: February 2016 Contract number: N/A Contractor: ADAS. Contract Manager: Lewis H Title: Tŷ Ddewi / St David’s Coast NVC Survey Report Author: Shepherd S Technical Editor: Lewis H Peer Reviewers Creer J, Chadwick M, Rimington N Approved By: Rimington N Restrictions: None Distribution List (core) NRW Library, Bangor 2 National Library of Wales 1 British Library 1 Welsh Government Library 1 Scottish Natural Heritage Library 1 Natural England Library (Electronic Only) 1 Distribution List (others) Recommended citation for this volume: Shepherd S, 2016. Tŷ Ddewi / St David’s Coast NVC Survey Report. NRW Evidence Report No: 143, 166pp, Natural Resources Wales, Bangor www.naturalresourceswales.gov.uk Page 3 Contents 1. Crynodeb Gweithredol .................................................................................................... 7 2. Introduction and Background .......................................................................................... 9 3. Methodology ................................................................................................................. 12 3.1. Survey Protocol .................................................................................................................12 3.2. Mapping Protocol ..............................................................................................................13 3.3. Limitations .........................................................................................................................14 4. Results ......................................................................................................................... 14 4.1. Community Descriptions ...................................................................................................19 4.1.1. Maritime Communities ....................................................................................................19 4.1.2. Heath Communities ........................................................................................................22 4.1.3. Woodland and Scrub Communities ................................................................................24 4.1.4. Grassland Communities .................................................................................................25 4.1.5. Mire Communities ...........................................................................................................26 4.1.6. Swamp and Tall Herb Fen Communities ........................................................................27 5. Scarce Plant Species .................................................................................................... 27 6. Conservation Assessment ............................................................................................ 31 7. References ................................................................................................................... 58 8. Appendix 1 Photographs .............................................................................................. 59 9. Appendix 2 Target Notes .............................................................................................. 78 10. Appendix 3 Quadrat Data ............................................................................................. 85 Data Archive Appendix ....................................................................................................... 165 www.naturalresourceswales.gov.uk Page 4 List of Figures Figure 1 Priority Areas Surveyed. ............................................................................. 11 Figure 2 NVC Survey Maps 1-20 .............................................................................. 36 www.naturalresourceswales.gov.uk Page 5 List of Tables Table 1 Summary of NVC Communities at St. David’s Head ................................... 15 Table 2 Notable Species Recorded .......................................................................... 29 Table 3 NVC Communities and Associated Annex 1 Habitats.................................. 31 Table 4 JNCC Desired Community Types and Geological Groups .......................... 32 www.naturalresourceswales.gov.uk Page 6 1. Crynodeb Gweithredol Mae arfordir Tŷ Ddewi wedi’i ddynodi’n Ardal Cadwraeth Arbennig (ACA) oherwydd y cymunedau llystyfiant ar y llethr arfordirol ac yn y rhostir. Er mwyn diweddaru set ddata sylfaenol Cyfoeth Naturiol Cymru (CNC) ar gyfer cynefinoedd arfordirol, i’w defnyddio ar gyfer gwaith rheoli a chanolbwyntio’r gwaith o fonitro llystyfiant, cafodd ADAS eu comisiynu gan Cyfoeth Naturiol Cymru yn 2015 i gynnal arolwg Dosbarthiad Llystyfiant Cenedlaethol (NVC). Roedd y contract yn canolbwyntio’n bennaf ar ddau ddarn o’r arfordir ger Pen-caer a Phenmaendewi ac roedd hefyd yn cynnwys darnau hir o’r arfordir i’r de o Dyddewi. Roedd protocol yr arolwg yn dilyn trefniadau arolygu safonol NVC fel y’u disgrifir gan Rodwell (1991, 1992, 1995 a 2000) a chafodd y llystyfiant ei fapio ar awyrluniau ar raddfa o 1:5000. Mapiwyd yr holl lystyfiant yn yr Ardaloedd Blaenoriaeth a bennwyd ymlaen llaw. Fodd bynnag, oherwydd cyfuniad o brysgwydd dyrys a/neu lethrau/clogwyni serth a pheryglus, nid oedd modd mynd i rai mannau. Mewn achosion felly, dibynnwyd ar graffu trwy sbienddrych er mwyn canfod cymunedau llystyfiant. Mae’r ardaloedd lle gwnaed hyn wedi’u hamlygu. Roedd safle’r arolwg NVC yn mesur cyfanswm o 556.87ha. Mapiwyd cyfanswm o 1035 o bolygonau ar lefel is-gymuned (neu weithiau ar lefel cymuned) neu fel mosaigau o un neu fwy o gymunedau/is-gymunedau. Cofnodwyd cyfanswm o 37 o gymunedau a 49 o is-gymunedau NVC. Roedd hyn yn cynnwys pum grŵp bras o gynefinoedd NVC: Cymunedau morol Cymunedau coetiroedd a phrysgwydd Cymunedau glaswelltir Cymunedau corsiog Cymunedau gwernydd a chorsydd calchog llystyfiant tal Y cynefinoedd o Atodiad 1 a nodir fel y prif reswm dros ei ddewis yn safle ACA yw ‘Clogwyni môr â llystyfiant o arfordiroedd yr Iwerydd a’r Baltig’ a ‘rhostiroedd sych Ewropeaidd’. Yn ardal yr arolwg, gwelwyd bod 34.47ha o glogwyni môr â llystyfiant a 124.55ha o rostir sych Ewropeaidd. Ar y cyfan, fodd bynnag, y mathau mwyaf cyffredin o gymunedau oedd W25 isdyfiant Pteridium aquilinum – Rubus fruticosus ac W23 prysgoed Ulex europaeus - Rubus fruticosus Cofnodwyd nifer o rywogaethau o blanhigion prin neu nodedig, nifer ohonynt o arwyddocâd cenedlaethol a lleol. Wrth asesu ardal yr arolwg yn erbyn meini prawf y JNCC, awgrymir bod yr ardal yn werthfawr o safbwynt cadwraeth ond mae awgrym hefyd y gallai ddod yn llai gwerthfawr gan nad oes cymaint o bori ag y bu ac y gallai hynny arwain at weld rhedyn a phrysgwydd yn lledaenu ar draul cymunedau morol. Fodd bynnag, os yw’r syniad hwnnw’n gywir, byddai modd rheoli’r tir yn briodol er mwyn gwella’r sefyllfa. www.naturalresourceswales.gov.uk Page 7 Executive Summary St. David’s coast has been designated as a SAC on account of its coastal slope and heathland vegetation communities. In order to update Natural Resources Wales (NRW) baseline data set for coastal habitats, to inform management and focus vegetation monitoring,