The conservation and amenity value of ball-clay ponds in the Isle of Purbeck, Dorset, UK

Abstract

Opencast mining is the principal method by which ball-clays are extracted from heathland in the Isle of Purbeck, Dorset, UK. An understanding of the substitute habitats so created is required if the environmental impact of this mode of extraction is to be assessed. This paper investigates the conservation and amenity value of the water bodies arising from 18th and 19th century workings in the Isle of Purbeck. The 16 ball-clay ponds studied varied widely in chemistry and supported a range of freshwater habitats and biotas. Several species of special conservation interest occurred and the ponds had a diverse dragonfly fauna. The acidic heathland ponds represent a habitat of local and diminishing distribution in lowland Britain. The more enriched, circum-neutral ponds supported fish populations of varying quality, some of which may have a considerable amenity value. Collectively, these ponds make a positive contribution to the ecological and landscape diversity of the Isle of Purbeck.