Ecological and nature conservation aspects of land affected by mining in the Yorkshire Coalfield.

Between 1992 and 1996, the ecology of sites affected by mining, (including former deep-mines, opencast restorations and subsidence wetlands) was investigated. The study sites were located throughout the 2500 sq.km of the Yorkshire Coalfield in northern England. Mining impacts on nature conservation and ecological processes were examined and related to past, present and proposed land-use and restoration practices. Detrimental effects of mining included historical direct land-take of wildlife sites and ongoing indirect pollution of watercourses from iron-enriched leachate. Significant nature conservation interest at international (European), national (British), regional (county/district) and local level was identified.On deep-mine sites (abandoned collieries and spoil-heaps) and some older opencast restorations, important features included: pioneer vegetation, grassland, heathland, woodland, vascular plants, amphibians, open ground insects and birds. On opencast wetland restorations and subsidence wetlands, key features were: aquatic and swamp vegetation, wintering wildfowl, breeding and passage birds, mammals, fish and invertebrates. Many sites were already used and valued by local people for amenity.The associated plant communities were described. The majority corresponded to species-poor analogues of the National Vegetation Classification. Four new widely distributed pioneer communities and sub-communities were identified. Developmental trends of communities from naturally regenerated sites and failed restorations were suggested, showing the likely successional pathways for the Coal Measures region. Faunal community structure and development, including colonisation, establishment and habitat associations were explored. Restored terrestrial sites, increasingly common after the contraction of the coal-mining industry from the mid-1980's, were found to be considerably poorer for wildlife than naturally regenerated sites, whilst wetland restorations appeared to be more variable in successfully creating wildlife habitats. Restorations followed techniques developed for amenity and agriculture. Nature conservation guidance had only been recently introduced, based on experience from traditional wildlife site management and case studies. Early successional stages and natural regeneration processes on topographically diverse landscapes were largely undervalued by restorationists in favour of large-scale intervention and fashionable habitat-types. This work advances the knowledge and understanding of ecosystems derived from the Coal Measures of northern England and provides a comprehensive review of the nature conservation value of land affected by mining in the region.