Agenda 21
A global action plan for the 21st century, part of the Convention on Biological Diversity which arose from the Rio Earth Summit (the UN Conference on Environment and Development, Rio de Janeiro, 1992). Agenda 21 aims to bring about more sustainable development, and calls specifically for the private sector’s active involvement in biodiversity matters. It emphasises that over and above the business case, and self-interest, companies have a responsibility to be part of the broader efforts to conserve biodiversity.

Agri-Environment Schemes
Government-funded initiatives to enable farmers to pursue more conservation oriented land management. The schemes of greatest relevance to nature conservation in England include Environmentally Sensitive Areas and Countryside Stewardship.

Alien species
A plant or animal species introduced to this country by non-natural means.

Ancient woodland
Sites believed to have been wooded continuously since at least 16OOAD.

Ancient semi-natural woodland
Ancient woodland which still consists of mainly native species, but which may have been subject to various types of management, such as coppicing. In many cases the woodland is likely to have originated from the original ‘wildwood’ which originally covered most of England.

AONB (Area of Outstanding Natural Beauty)
A statutory designation aiming to conserve the natural scenic beauty of an area. Identified by the Countryside Commission and administered by local authorities.

Assemblage
A group of species characteristically found in the same location due to the similarity of their habitat requirements.

Atlantic
Botanical term for species with a western distribution in the British Isles, where the climate is at its wettest and mildest.