Field meeting in Gower, South Wales

Abstract

The Gower peninsula (Fig. 1), is approximately 20 km long and 10 km wide; it forms the western extremity of the vice-county of Glamorgan (V.C. 41). The westerly, coastal position, and the rural character of the peninsula have largely protected it from air pollution. The climate is generally moist and mild, annual rainfall being around 1020 mm, rising to 1150 mm on the higher ground; it is spread over approximately 160 wet days. The climate is drier and warmer than elsewhere in Wales with the exception of some coastal areas in the northwest and southwest. Solid geology largely comprises Carboniferous Limestone, with Old Red Sandstone forming ridges of high ground. The Autumn Meeting of the British Lichen Society, based at Parkmill, was held from 10-15 September 1990, and attracted 17 members. Carboniferous Limestone The greater part of southern Gower is composed of a hard, pure limestone that is well exposed in coastal cliffs and along the sides of narrow dry valleys that run down to the sea. As the rocks are sharply folded it is possible to find surfaces of all aspects and inclinations. Most exposures are in a natural condition, although the frequent remains of lime kilns suggest locally extensive former quarrying. Where long-abandoned quarries could be definitely identified, they showed little reduction in species diversity compared with adjacent areas. As FIG. 1. Map of Gower showing locations of principal sites visited, and the lines of the 10 km National Grid. Scale = 5 km. Inset map of Wales shows location of Gower. Localities:

Field Meeting at Grange-Over-Sands, Lancashire

“…Toninia verrucarioides was regularly found overgrowing Placynthium nigrum. Placynthium subradiatum was also present, together with a small, unnamed, granular Placynthium that forms small arcs and hollow circles; it has been reported from a similar habitat on the Gower peninsula (Gilbert et al 1992). The crevice flora is poor on parts of the cliff exposed to salt spray but increases with height above sea level.…”