Peat Bog field trip



Peat Bog Course with Richard Lindsay August 16th 2013- notes from a field visit to Uradale
Part 1

  1. A “Transition mire” – a flush going back to bog. Sphagnum palustre is dominant at the moment, polytrichum sp moss indicates a flush, presence of holcus sp could indicate that this was an old peat cutting.  Polytrichum commune stems can run for several metres and it is typical of old abandoned in-bye land.  (very often digging into a mat of polytrichum with juncus tufts will reveal a sheeps skull- we didnt try here!) Juncus squarrosus could indicate that there was peat cutting here, it out competes other species where the organic layer is only as few cms thick and generally indicates that there has been human activity. S. recurvum (the most plastic of all the sphagnums  , it will recolonise dammed drains or commercial peat cut areas) and s. capillifolium are also present.  Transition A1 hollow/ flush (acid fen).
 

2.       Example of “Haplotelmic bog” (bog without acrotelm) or modified blanket bog. Not an active bit of bog as there is no significant cover of peat forming vegetation. On basis of NVC classification which just uses vegetation to classify the habitat it would be classed as degraded blanket bog. NB “heathland” has only a very thin organic layer, the depth of peat was measured here using connecting rods and found to be over 1.7m so although the vegetation is of heathland type this is not heathland. Definitions for depth of peat indicative of bog vary – an ecologist regards 30cm depth of peat as meaning “peatland” but the Phase 1 Habitat survey definition requires 1m of peat. 






3.       Regenerated secondary peat bog in an area of old peat cuttings
Flushed or enriched vegetation type typical of very old abandoned in-bye land or due to seepages from a flush. The juncus effusus and mounds of s. palustre are typical. There is vigorous peat formation but it will take 200 years to revert to blanket bog- the surface is enriched so the peat has to build up (about 1mm a year) until the enrichment is no longer in the root zone.
 




4. Surface Flush
A mineral enriched flush, ie a fen, within the blanket “bog” habitat. The whole landscape can be referred to as “blanket mire” and included in this will be blanket bog, upland fens and flushes.The sedge carex panacea can cope with the low nutrient levels in this example of a “surface flush”. Peat is about 0.8m deep here. The sphagnum species present are s. subsicundum, s. denticulatum and s. recurvum.






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