Biodiversity and Conservation

, Volume 16, Issue 10, pp 2821–2846 | Cite as

Recent vegetation history of Drygarn Fawr (Elenydd SSSI), Cambrian Mountains, Wales: implications for conservation management of degraded blanket mires

  • F. M. Chambers
  • D. Mauquoy
  • E. W. Cloutman
  • J. R. G. Daniell
  • P. S. Jones
Original Paper


Many areas of blanket mire in Britain display apparently degraded vegetation, having a limited range of ericaceous and Sphagnum species. Data are presented here from Wales from the upland locality of Drygarn Fawr (Elenydd SSSI), which is dominated overwhelmingly by Molinia caerulea. Palaeoecological techniques were used to chronicle vegetation history and to determine the nature and timing of vegetation changes, as an aid to devising conservation management and restoration strategies. Although for the past 2000 years the pollen and plant macrofossil data indicate some evidence for cyclic vegetation change, they demonstrate that here the major vegetation change post-dated the start of the industrial revolution. The palaeoecological data show a greater proportion of Sphagnum than currently. Local extinction of some species (e.g., Myrica gale) apparently took place in Medieval times, but most of the degradation and floral impoverishment apparently occurred during the 20th Century. The implications for conservation management are far-reaching. The overwhelming dominance of Molinia is clearly unprecedented. While it was locally present for hundreds of years, some factor(s)—possibly a change in grazer and grazing regime—encouraged its recent ascendancy in the 20th Century. Consequently, any management attempts to reduce the pre-eminence of Molinia would not be countering an ingrained, long-established dominance. It is suggested that investigation of degraded blanket mires elsewhere by historical and multi-proxy palaeoecological techniques—through multiple, dated cores to track species extinctions and directional vegetation changes—would help ascertain previous mire floras and so indicate a range of restoration targets for mire vegetation.


Blanket mires Degraded mires Mire conservation Palaeoecological techniques Plant macrofossil analysis Pollen analysis Wales 



Research was carried out under CCW contract number FC 73-01-172 ‘Recent human impact on Welsh Blanket bogs’, as a follow-up to a pilot study of the same name and contract number. We thank Chris Friend, for field and laboratory assistance; Charlotte Cook, for laboratory assistance; the National Trust and the Elan Trust for site access; and Marcus Yeo, for commissioning the work, and for field assistance and information on the field areas.


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Copyright information

© Springer Science+Business Media, Inc. 2007

Authors and Affiliations

  • F. M. Chambers
    • 1
  • D. Mauquoy
    • 2
  • E. W. Cloutman
    • 1
  • J. R. G. Daniell
    • 1
  • P. S. Jones
    • 3
  1. 1.Centre for Environmental Change and Quaternary ResearchUniversity of GloucestershireCheltenhamUK
  2. 2.Department of Geography & EnvironmentUniversity of AberdeenAberdeenUK
  3. 3.Countryside Council for WalesBangor, GwyneddUK

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