An example may be in a beach
dune system where the impact of the human race has caused footpath
erosion to occur, affecting the
vegetation so that feet trampling on the dune plants eventually destroys them. The uplands of Northern
England were once covered by
deciduous woodland. Some
heather would have been present, but in relatively small amounts. Gradually the
forests were removed during the early
Middle Ages for
timber and
fuel purposes, and to create space for
agricultural activities. The
soil deteriorated as a result and heather came to dominate the
plant community.
Sheep grazing was the major form of agriculture in the area at the time and the sheep prevented the re-growth of woodland by destroying any young
saplings. In more recent times the process of controlled
burning of the heather has taken place. The heather is burnt after 15 years of its life cycle before it becomes mature and allows
colonisation of the area by other
plants. The ash adds to the
soil fertility and the new growth that results increase the productivity of the ecosystem and provides the sheep with a more nutritious diet than is provided by the elder heather. This controlled burning maintains a plant community which is not the
climatic climax of the area, and is therefore a plagioclimax. In
Studland Heath in Dorset, England, the management agency prevents the climax community (in this case trees) becoming established. At Studland the aim is to keep the area as heathland, so that the small reptiles that inhabit the dune system continue to survive. If the area is allowed to develop naturally into woodland, the reptiles would be replaced by other species of animals. ==References==