|
Saltmarsh summary of grazing effects
Grazing
pressure is a significant determinant of the nature of saltmarsh vegetation
as a habitat for plants and animals. Four
states have been identified based on the grazing regime namely:
- heavy
grazing - height <10cm, all standing crop removed;
- moderate
grazing - loss of structural diversity standing crop almost completely
removed;
- light
grazing - structural diversity and majority of vegetation retained;
- abandoned
grazing - matted vegetation, no standing crop removed.
The level of grazing can dramatically affect the value of the saltmarsh (see
Figure).
Caption:
Summary of nature conservation interest in relation to grazing levels on
saltmarshes in northwest Europe.
Caption:
Grazed and ungrazed saltmarsh Bridgwater Bay, Somerset showing the impact
on the structure of the marsh.
The conservation value of each of these is discussed in some detail (Chapter
5 pages 83-89, Doody 2001) where recommendations
are made for the most appropriate management.
| General guidance: The key to deciding on a grazing regime lies
in understanding the historical management and the way in which this has
helped create and sustain the existing interest. Recent changes in management
may have caused these interests to be compromised, though the change may
be easily reversible by adopting an appropriate grazing
regime. Note: Restoring saltmarsh habitat i.e. reversing
saltmarsh
erosion is considered in a separate section. |
References
Doody, J.P.
2001.
Coastal Conservation and Management: an Ecological Perspective. Kluwer, Academic Publishers, Boston, USA, 306 pp.
Conservation Biology Series, 13
|
