Brownfield and Post-industrial Land
This habitat occurs in various man-made situations, including disused quarries, pits, mine spoil and abandoned industrial sites. In some instances sites have developed well established semi-natural vegetation as a result of years of natural recolonisation or as the result of management to re-create wildlife habitats. On some sites the succession of plant communities to woodland and scrub is slowed or arrested by poor nutrient status, toxity of substrate or repeated disturbance. Characteristic pioneer communities of lichens, bryophytes and higher plants occur. Post-industrial habitats are especially important in lowland areas where more ‘natural’ equivalents are rare, and where threats of development or reclamation may be intense. They support a range of wildlife including several UK BAP priority species, and other species of conservation importance.
Of particular importance to the North East Region are a specialised type of habitat known as calaminarian grasslands. This is a rare habitat (listed on Annex 1 of the EU ‘Habitats Directive’) which occurs on soils or gravels contaminated with heavy metals such as lead and zinc. A number of examples occur within the North Pennines (Teesdale, Weardale and particularly Tynedale) and support a distinctive flora of species that are tolerant of high levels of heavy metals, such as spring sandwort Minuartia verna and alpine pennycress Thlaspi caerulescens, and a number of interesting lichen species. Some of the best examples of these can be found on the river gravels and alluvial grasslands of the River Tyne/South Tyne system. The international importance of these has been recognised in their designation as the Tyne & Allen River Gravels SAC.