Rhododendron ponticum: Hanes ei gyflwyno a’i ymlediad yng Nghymru, y bygythiad i fioamrywiaeth a’r dyfodol


Rhododendron ponticum: Hanes ei gyflwyno a’i ymlediad yng Nghymru, y bygythiad i fioamrywiaeth a’r dyfodol
Gruffydd Jones et al.

Llwyn bytholwyrdd coediog yw Rhododendron ponticum L., sy’n aelod o deulu’r Ericaceae. Daw yn wreiddiol o Sbaen, Mynyddoedd y Cawcasws ac arfordir y Môr Du. Cafodd ei gyflwyno i Brydain yn y ddeunawfed ganrif. Ers hynny, fodd bynnag, mae wedi datblygu i fod yn un o rywogaethau ymledol mwyaf niweidiol Prydain, gan achosi difrod ecolegol ac economaidd sylweddol. Bydd yr erthygl hon yn trafod hanes R. ponticum yng Nghymru, gan ystyried y ffactorau amgylcheddol a chymdeithasol sydd wedi cyfrannu at ei lwyddiant yma. Disgrifir y sefyllfa bresennol yng Nghymru, gan gynnwys y mathau o niwed y mae’n eu hachosi, yn ogystal â’r ymdrechion i reoli ei ymlediad. I gloi, bydd yr erthygl yn edrych ar rai o heriau amgylcheddol y dyfodol, a sut y gall y rhain ddylanwadu ar ymlediad R. ponticum.


Cyfeiriad:

 
  	Gruffydd Jones, John Scullion, Ana Winters, Rhys Owen, John Ratcliffe, Doug Oliver a Dylan Gwynn-Jones, ‘Rhododendron ponticum: Hanes ei gyflwyno a’i ymlediad yng Nghymru, y bygythiad i fioamrywiaeth a’r dyfodol’, Gwerddon, 27, Hydref 2018, 20–38.
   

Allweddeiriau

 
    Rhododendron, amgylchedd, ymledol, ecoleg, cadwraeth, Eryri, pridd, metabolion, alelopathi.
    

Llyfryddiaeth:

 
  	
  1. Aerts, R. (1999), ‘Interspecific competition in natural plant communities: mechanisms, trade-offs and plant-soil feedbacks’, Journal of Experimental Botany, 50 (330), 29–37.
  2. Akula, R., a Ravishankar, G. A. (2011), ‘Influence of abiotic stress signals on secondary metabolites in plants’, Plant Signaling & Behavior, 6 (11), 1720–31.
  3. Awdurdod Parc Cenedlaethol Eryri (2016), Hanes Plas Tan y Bwlch, <http://www.eryrinpa.gov.uk/cym/study-centre/history?name=> [Cyrchwyd: 13 Rhagfyr 2016].
  4. Batten, L. A. (1976), ‘Bird communities of some Killarney woodlands’, Proceedings of the Royal Irish Academy. Section B: Biological, Geological, and Chemical Science, 76, 285–313.
  5. Blair, A. C. et al. (2006), ‘A lack of evidence for an ecological role of the putative allelochemical (±)-catechin in spotted knapweed invasion success’, Journal of Chemical Ecology, 32 (10), 2327–31.
  6. Brasier, C. M. et al. (2004), ‘Sudden oak death (Phytophthora ramorum) discovered on trees in Europe’, Mycological Research, 108, 1107–08.
  7. Chadfield, V., a Pautasso, M. (2012), ‘Phytophthora ramorum in England and Wales: which environmental variables predict county disease incidence?’, Forest Pathology, 42, 150–59.
  8. Chamberlain, D. F. (1982), ‘A revision of Rhododendron II. Sub-genus Hymenanthes’, Notes from the Royal Botanic Gardens Edinburgh, 39, 209–486.
  9. Chou, S. C. et al. (2010), ‘Allelopathic potential of Rhododendron formosanum Hemsl in Taiwan’, Allelopathy Journal, 25 (1), 73–91.
  10. Clinton, B. D., a Vose, J. M. (1996), ‘Effects of Rhododendron maximum L. on Acer rubrum L. seedling establishment’, Castanea, 61 (1), 38–45.
  11. Colak, A. H. et al. (1998), ‘Rhododendron ponticum in native and exotic environments, with particular reference to Turkey and the British Isles’, Journal of Practical Ecology and Conservation, 2, 34–40.
  12. Cross, J. R. (1975), ‘Rhododendron Ponticum L.’, The Journal of Ecology, 63 (1), 345–64.
  13. Cross, J. R. (1981), ‘The establishment of Rhododendron ponticum in the Killarney Oakwoods, S. W. Ireland’, Journal of Ecology, 69 (3), 808–24.
  14. Cross, J. R. (1982), ‘The invasion and impact of Rhododendron ponticum in native Irish vegetation’, Journal of Life Sciences Royal Dublin Society, 3 (1), 209–20.
  15. Cyfoeth Naturiol Cymru (2017), Good Practice Guide: Forest Resilience Guide 1 – Improving the structural diversity of Welsh woodlands, <https://naturalresources.wales/media/681029/gpg6_forest-resilience-1_structural-diversity.pdf> [Cyrchwyd: 10 Ebrill 2017].
  16. Dehnen-Schmutz et al. (2004), ‘Controlling Rhododendron ponticum in British Isles: An economic analysis’, Journal of Environmental Management, 70 (4), 323–32.
  17. Dehnen-Schmutz, K., a Williamson, M. (2006), ‘Rhododendron ponticum in Britain and Ireland: Social, economic and ecological factors in its successful invasion’, Environment and History, 12 (3), 325–50.
  18. Erfmeier, A., a Bruelheide, H. (2004), ‘Comparison of native and invasive Rhododendron ponticum populations: Growth, reproduction and morphology under field conditions’, Flora – Morphology, Distribution, Functional Ecology of Plants, 199, 120–33.
  19. Erfmeier, A., a Bruelheide, H. (2005), ‘Invasive and native Rhododendron ponticum populations: Is there evidence for genotypic differences in germination and growth?’, Ecography, 28 (4), 417–28.
  20. Ermischer, G. (2004), ‘Mental landscape: landscape as idea and concept’, Landscape Research, 29 (4), 371–83.
  21. Esen, D. et al. (2006), ‘Ecology, competitive advantges, and integrated control of Rhododendron: an old ornamental yet emerging invasive weed around the globe’, Floriculture, Ornamental and Plant Biotechnology, 3, 408–21.
  22. Esen, D., a Zedaker, S. M. (2004), ‘Control of Rhododendron (Rhododendron ponticum and R. flavum) in the eastern beech (Fagus orientalis) forests of Turkey’, New Forests, 27 (1), 69–79.
  23. Gonzalez-Perez, J. A. et al. (2011), ‘Geochemical and ecological significance of soil lipids under Rhododendron ponticum stands’, Environmental Chemistry Letters, 9 (4), 453–64.
  24. Gritten, R. H. (1995), ‘Rhododendron ponticum and some other invasive plants in the Snowdonia National Park’, yn Pysek, P. et al., Invasions: General Aspects and Special Problems, Amsterdam, SBP Academic Publishing.
  25. Harris, C. M. et al. (2009), ‘Invasive species control: Incorporating demographic data and seed dispersal into a management model for Rhododendron ponticum’, Ecological Informatics, 33, 1456–66.
  26. Higgins, G. T. (2008), ‘Rhododendron ponticum: A guide to management on nature conservation sites’, Irish Wildlife Manuals, No. 33, Dublin, National Parks and Wildlife Service, Department of the Environment, Heritage and Local Government, Dublin, Ireland.
  27. Higgins, S. I., a Richardson, D. M. (1996), ‘A review of models of alien plant spread’, Ecological Modelling, 87, 249–65.
  28. Holmes, G. D. (1957), ‘Experiments on the chemical control of Rhododendron ponticum’, Forestry Commission: Forest Record, 34, 1–7.
  29. Hough, R. L. et al. (2010), ‘Degradation of yew, ragwort and rhododendron toxins during composting’, Science of the Total Environment, 408 (19), 4128–37.
  30. Jackson, P. (2008), ‘Rhododendron in Snowdonia and a strategy for its control’, <http://www.eryri-npa.gov.uk/__data/assets/pdf_file/0020/68600/Rhododendron-Strategy-Final.pdf> [Cyrchwyd: 13 Rhagfyr 2017].
  31. Jaiswal, R. et al. (2012), ‘Identification and characterization of proanthocyanidins of 16 members of the Rhododendron genus (Ericaceae) by tandem LC-MS’, Journal of Mass Spectrometry, 47 (4), 502–15.
  32. Jones, P. H. (1972), ‘Succession in breeding bird populations of sample Welsh oakwoods’, British Birds, 65, 291–9.
  33. Judd, S., a Rotherham, I. D. (1992), ‘The phytophagous insect fauna of Rhododendron ponticum’, Entomologist, 111 (3), 134–50.
  34. Keane, R. M., a Crawley, M. J. (2002), ‘Exotic plant invasions and the enemy release hypothesis’, Trends in Ecology and Evolution, 17 (4), 164–70.
  35. Lei, T. T. et al. (2002), ‘Effects of Rhododendron maximum thickets on tree seed dispersal, seedling morphology, and survivorship’, International Journal of Plant Sciences, 163 (6), 991–1000.
  36. Li, Z. H. et al. (2010), ‘Phenolics and plant allelopathy’, Molecules, 15 (12), 8933–52.
  37. Lin, L. C. et al. (2011), ‘Decomposition of organic matter by the ericoid mycorrhizal endophytes of Formosan rhododendron (Rhododendron formosanum Hemsl.)’, Mycorrhiza, 21 (5), 331–9.
  38. Llywodraeth Cynulliad Cymru (2009), Coetiroedd i Gymru, <http://gov.wales/docs/drah/publications/090324-woodlands-for-wales-strategy-cy.pdf> [Cyrchwyd: 7 Mawrth 2017).
  39. Llywodraeth Cynulliad Cymru (2013), Invasive Alien Species - Research Note, <http://www.assembly.wales/research%20documents/invasive%20alien%20species%20-%20research%20note-08042013-245303/rn13-006-english.pdf> [Cyrchwyd: 5 Hydref 2017].
  40. Maron, J. L., a Vila, M. (2001), ‘When do herbivores affect plant invasion? Evidence for the natural enemies and biotic resistance hypotheses’, Oikos, 95, 361–73.
  41. Mejías, J. A. et al. (2002), ‘Reproductive ecology of Rhododendron ponticum (Ericaceae) in relict Mediterranean populations’, Botanical Journal of the Linnean Society, 140 (3), 297–311.
  42. Mifsud, D. et al. (2010), ‘Other Hemiptera Sternorrhyncha (Aleyrodidae, Phylloxeroidea, and Psylloidea) and Hemiptera Auchenorrhyncha. Chapter 9.4’, BioRisk, 4, 511–52.
  43. Milligan, G. et al. (2016), ‘Winners and losers in a long-term study of vegetation change at Moor House NNR: Effects of sheep-grazing and its removal on British upland vegetation’, Ecological Indicators, 68, 89–101.
  44. Milne, R. I., ac Abbott, R. J. (2000), ‘Origin and evolution of invasive naturalized material of Rhododendron ponticum L. in the British Isles’, Molecular Ecology, 9 (5), 541–56.
  45. Murphy, J. et al. (2010), Climate change projections, Climate Change and Agriculture, <http://ukclimateprojections.defra.gov.uk> [Cyrchwyd: 11 Ionawr 2017).
  46. Navarro, L. M., a Pereira, H. M. (2012), ‘Rewilding abandoned landscapes in Europe’, Ecosystems, 15, 900–12.
  47. Nilsen, E. T. et al. (1999), ‘Inhibition of seedling survival under Rhododendron maximum (Ericaceae): could allelopathy be a cause?’, American Journal of Botany, 86 (11), 1597–1605.
  48. Nolan, N. E. et al. (2014), ‘Activated carbon decreases invasive plant growth by mediating plant-microbe interactions’, AoB PLANTS, 7, 1–12.
  49. Perry, L. G. et al. (2007), ‘Concentrations of the allelochemical (±)-catechin in Centaurea maculosa soils’, Journal of Chemical Ecology, 33 (12), 2337–44.
  50. Peterken, G. F. (2001), ‘Ecological effects of introduced tree species in Britain’, Forest Ecology and Management, 141, 31–42.
  51. Pichersky, E., a Gang, D. R. (2000), ‘Genetics and biochemistry of secondary metabolites in plants: An evolutionary perspective’, Trends in Plant Science, 5 (10), 439–45.
  52. Plocher, A. E., a Carvell, K. L. (1987), ‘Population dynamics of rosebay rhododendron thickets in the southern Appalachians’, Bulletin of the Torrey Botanical Club, 114 (1142), 121–6.
  53. Popescu, R., a Kopp, B. (2013), ‘The genus Rhododendron: An ethnopharmacological and toxicological review’, Journal of Ethnopharmacology, vol. 147 (1), 42–62.
  54. Qiang, Y. et al. (2011), ‘Chemical constituents of plants from the genus Rhododendron’, Chemistry and Biodiversity, 8 (5), 792–815.
  55. Rice, E. L. (1979), ‘Allelopathy: An update’, The Botanical Review, 45 (1), 15–109.
  56. Rice, E. L. (1984), Allelopathy, 2il argraffiad (Llundain: Academic Press).
  57. Rotherham, I. D., ‘The ecology of Rhododendron ponticum L. with special reference to its competitive and invasive capabilities’, traethawd PhD, University of Sheffield, Sheffield, 1983.
  58. Rotherham, I. D. (1986), ‘The introduction, spread and current distribution of Rhododendron ponticum in the Peak District and Sheffield area’, Naturalist, 111, 61–7.
  59. Rotherham, I. D. (2001), ‘Rhododendron gone wild: Conservation implications of Rhododendron ponticum in Britain’, Biologist, 48 (1), 7–11.
  60. Rotherham, I. D., a Read, D. J. (1988), ‘Aspects of the ecology of Rhododendron ponticum with reference to its competitive and invasive properties’, Aspects of Applied Biology, 16, 327–35.
  61. Shaw, M. W. (1984), ‘Rhododendron ponticum: Ecological reasons for the success of an alien species in Britain and features that may assist in its control’, Aspects of Applied Biology, 5, 231–42.
  62. Snowdonia Rhododendron Partnership (2015), The Ecosystem Benefits of managing the invasive non–native plant Rhododendron ponticum in Snowdonia, <http://www.eryrinpa.gov.uk/__data/assets/pdf_file/0019/546112/Rhododendron-in-Snowdonia.pdf> [Cyrchwyd: 12 Rhagfyr 2016].
  63. Stephenson, C. M. et al. (2007), ‘Testing mechanistic models of seed dispersal for the invasive Rhododendron ponticum (L.)’, Perspectives in Plant Ecology, Evolution and Systematics, 9 (1), 15–28.
  64. Stephenson, C. M. et al. (2006), ‘Modelling establishment probabilities of an exotic plant, Rhododendron ponticum, invading a heterogeneous, woodland landscape using logistic regression with spatial autocorrelation’, Ecological Modelling, 193, 747–58.
  65. Stout, J. C. et al. (2006), ‘Pollination ecology and seed production of Rhododendron ponticum in native and exotic habitats’, Biodiversity and Conservation, 15 (2), 755–77.
  66. Suc, J.-P. (1984), ‘Origin and evolution of the Mediterranean vegetation and climate in Europe’, Nature, 307 (5950), 429–32.
  67. The Wildlife Trusts (dim dyddiad), Rhododendron Leafhopper, <http://www.wildlifetrusts.org/species/rhododendron-leafhopper> [Cyrchwyd: 12 Rhagfyr 2016].
  68. Thomson, A. G. et al. (1993), ‘Factors Affecting the Distribution and Spread of Rhododendron in North Wales’, Journal of Environmental Management, 39 (3), 199–212.
  69. Walker, J. F. et al. (1999), ‘Suppression of ectomycorrhizae on canopy tree seedlings in Rhododendron maximum L. (Ericaceae) thickets in the southern Appalachians’, Mycorrhiza, 9 (1), 49–56.
  70. Wang, C. M. et al. (2013), ‘The Impact of microbial biotransformation of catechin in enhancing the allelopathic effects of Rhododendron formosanum’, PLoS ONE, 8 (12), <http://dx.plos.org/10.1371/journal.pone.0085162> [Cyrchwyd: 6 Rhagfyr 2016].
  71. Williams, F. et al. (2010), The economic cost of invasive non-native species on Great Britain, <http://www.invasivespeciesscotland.org.uk/wp-content/uploads/2012/09/The_Economic_Cost_of_Invasive_Non-Native_Species_to_Great_Britain _-_Final_Report1.pdf> [Cyrchwyd: 12 Rhagfyr 2016].
  72. Williams, R. D., a Hoagland, R. E. (1982), ‘The effects of naturally occurring phenolic compounds on seed germination’, Weed Science, 30 (2), 206–12.
  73. Wong, J. et al. (2002), Report of the rhododendron feasibility study <http://www.wildresources.co.uk/reports/rhodo_eng.pdf> [Cyrchwyd: 6 Rhagfyr 2016].
  74. Yela, J. L., a Lawton, J. H. (1997), ‘Insect herbivore loads on native and introduced plants: a prelimary study’, Entomologia Experimentalis et Aplicata, 85 (3), 275–9.