Wednesday, 29 April 2020

Vegetation Surveys


Vegetation Changes
  • Two reports established trends in the change of vegetation on Molland Moor.
  • The 2013 report by Dave Boyce, the independent ecologist on the Graze the Moor project, drew attention to the loss of heather cover, in the period 1991 – 2013, and the increase in the area of Molinia.
    • The heather cover on Molland Moor has declined very markedly over the last two decades.
    • This decline is continuing and without management, heather dominant areas will continue to degenerate towards species-poor, Molinia dominated vegetation.
  • The vegetation changes were confirmed by the aerial photo analysis carried out by the Devon Biodiversity Records Office (DBRC). 
    • This analysis considered the vegetation changes that have taken place since the post-war aerial photographs were taken in 1947. 
    • The area of heather has declined by 56.2% in this period.
Figure 1: Decline in Heather Cover and Increase in Grass and Bog areas

Annual Vegetation Monitoring
  • Since 2012, Natural England has carried out annual surveys to monitor the impact of management on the vegetation on Molland Moor. Each year, 28 points were surveyed across the moor.
  • There are two SSSI units on the moor, and the condition of both is assessed as “Unfavourable – recovering”. For more information see the designated Sites webpage: http://bit.ly/2I29w1Y
Conclusions
  • The decline in the cover of heather and the expansion in the area of Molinia, since 1947, has been significant.
  • One of the aims of the project was to prevent further change and in time it is hoped that some of this change can be reversed.
  • Overgrazing of heather during the winter months is beginning to show through and to be a concern.
  • There is a suggestion that stock numbers could be increased to assess the impact of higher grazing pressure on old stands of heather and areas where Molinia is dominant.
Further Information

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