The nature of a pond is determined by the following factors:
- permeability of the pond lining
- water supply, and the subsequent water levels within the pond
- soil, silt or other substrate lining the pond
- edge treatment of the pond
- depth of the pond
- type and amount of vegetation
- deliberate introduction of pond fauna, or measures to encourage or discourage them.
These factors need to be taken into account at the design stage, although subsequent management can be flexible as the pond develops.
In general, the more artificial the pond lining and water supply, the more limited are the options for management. In particular, most artificial linings require fairly constant water levels throughout the year, as exposed artificial linings are prone to damage. Seasonally fluctuating water levels are a feature of natural ponds, and a factor on which many pond organisms rely, but is one which may not be compatible with an artificial pond.
An artificial pond which is managed to remain approximately the same from year to year can be valuable for education, amenity, and wildlife. Equally valid for wildlife, especially where there is sufficient space, is to create a pond and then leave it to develop naturally through its succession, and then a few years later, dig another one nearby, resulting in a range of pond and wetland habitats which change from year to year. These are more likely to mimic the natural waterway and wetland habitats created by geological and biological processes before man’s intervention in the landscape.
Thus, although there are definite techniques which need to be followed for the successful creation of a pond for a particular purpose, the whole range of wetland habitats from open water, through apparently bare mud to damp grassland and woodland have their own value. The ‘classic’ pond with open water, fringing irises and reeds, amphibians and dragonflies, is only one of many options.
It is not always best to try and provide the full range of habitats in a single pond, as there may then be too little space to support viable communities, especially of invertebrates, in each part of the range. It may be better to develop separate ponds, each with a distinctive character determined by factors such as water depth, shade and vegetation type. Let each pond do one thing really well!
