Purpose of the Manual • Structure of the Manual
Purpose of the Manual
Saltmarsh has a value that is related to its flood and coastal defence function and ecosystem and conservation importance, as well as its role in pollution control, waste disposal and the maintenance of water quality, fisheries, agriculture, recreation and tourism. This value is based on the interaction of its basic components (soil, water, flora and fauna), their physical shape (including channels and saltmarsh surfaces) and the assemblage of plants and animals they hold. It is, therefore, important to develop an understanding of both the requirements of saltmarsh and when and how to intervene to manage it.
In the context of the wider estuary environment, saltmarsh maintenance, restoration or enhancement is increasingly being considered as a means of managing flood risk. It also has the advantage of enhancing the conservation importance of a ‘natural’ as well as a frequently designated, priority and Biodiversity Action Plan habitat.
The Saltmarsh Management Manual describes what it is that needs to be managed and aims to help develop an understanding of how to evaluate the need for management intervention and the form that intervention might take. The Manual includes details of a number of techniques that can be applied for maintaining, restoring, enhancing or creating saltmarsh. The focus of the Manual is on managing existing saltmarsh environments. Although creation is not strictly related to the management of ‘existing’ saltmarsh, it is also considered because it represents an important option for the future management of the coast/estuaries and a lot of information pertinent to the creation of a new habitat can apply to the restoration or enhancement of an existing resource that is declining.
Guidance is provided in this Manual on determining the most appropriate option and/or technique for saltmarsh management based on the requirements of the site in question. That is, the Manual is aimed at assisting coastal and estuarine managers in the identification of the problems that a saltmarsh may have (if any) and the determination of an appropriate management response (i.e. the selection of a solution or range of potential solutions).
As a general rule, management will not be required where the saltmarsh remains in a constant, healthy, functioning state and, consequently, can respond to change (such as sea level rise) and adapt to most physical changes. Conversely, if change is particularly rapid, the saltmarsh is becoming degraded (including becoming more juvenile in its plant assemblages) or is physically eroding, then a programme of remedial work is more likely to be required. Saltmarshes can degenerate for a number of reasons, including sea level rise, changes in drainage patterns, disruption to the estuarine processes and changes in land use on or adjacent to the marsh. Saltmarshes also go through natural cycles of development and decline as an ephemeral feature on many coastlines over the long term.
To determine the best approach to management, it is important to understand why such change is occurring and to identify those changes that are the result of a local impact and those where it is part of a wider scale of change. This, in turn, will influence the choice of the most appropriate management technique (if management is appropriate at all); by identifying the nature of the problem the solution is more likely to present itself.
