Biodiversity
Biodiversity is defined simply as the variety of life, and it includes all the different habitats and species in the world.
Biolandscape map
The
Biolandscape map is simply the Landscape Type map overlain with the biomap. It highlights the variation in bioscores both within and between different landscape types.
Biomap
The
Biomap has been derived from an assessment of all the individual landscape description units in the county. It is basically a measure of the range and type of habitats found within each unit. Those units which have a wide range of habitats, including those of national or international importance, score more highly compared with those with fewer habitats of just local importance. Each unit has been assigned a bioscore and this, in turn, places it into a specific bioband. For example, if a unit has a bioscore greater than 150 the it falls within the very high bioband, whereas if its bioscore is less than 30 it is grouped within the low bioband.
Joint countryside character areas
As a result of work undertaken in the 1990s, England’s landscape was divided into 159 different character areas. These are broad areas of countryside, such as the Cotswolds or Chilterns, which have similar landscape, biodiversity and historical characteristics.
Landscape character
Landscape character has been defined as a distinct, recognisable pattern of elements in the landscape that makes one landscape different from another. This distinction makes no qualitative judgements about different landscapes. Although landscape character assessment takes into account the built environment, the emphasis for the Oxfordshire and Wildlife Study is mainly on the relationship between landscape character and biodiversity.
Landscape description units
These units are further subdivisions of the larger character areas, and they provide a more detailed understanding of the more subtle variation that exists within each of the character areas. Landscape description units nest within the character areas and are part of a hierarchical division throughout the whole of England. There are over 240 of these in Oxfordshire and all the maps and descriptions in the study are based on landscape and habitat surveys undertaken at this scale (see the
Regional character map)
Landscape types
The
landscape types are aggregations of individual landscape description units with a similar pattern of geology, topography, land use and settlements. They are named in a way which reflects their characteristic land cover, eg Wooded Pasture Valleys and Slopes. There are 24 separate landscape types within the county.
Local character areas
Each
landscape types consists of a number of different landscape description units. To provide some local identity within the county these units have been called local character areas and are usually named after a nearby village or settlement.
Priority habitats
Throughout the UK there are a number of
priority habitats - particular habitats which are deemed to be of national/international importance. Their conservation is therefore regarded as a priority within the Biodiversity Action Plan (BAP) of the UK (they are usually referred to as UK BAP priority habitats). Oxfordshire supports several of these priority habitats including calcareous (chalk or limestone) and neutral grassland. The majority of priority habitats are associated with the designated sites described under wildlife habitats (see below).
Regional character areas
Regional character areas are the parts of each joint character area which fall within Oxfordshire. There are nine of these (see the Regional Character map), and they include part of the Chilterns, Cotswolds, North Wessex Downs, the Midvale ridge and Northamptonshire uplands. The Upper Thames Clay Vales Joint Character Area has been subdivided into three Regional Character Areas within the County:
- the Upper Thames Vale
- the Vale of White Horse
- the Vale of Aylesbury
Wildlife habitats
On the individual landscape type maps some of the local character areas are overlain by coloured dots. These represent the most important surviving wildlife habitats within the county. They usually have a statutory or non-statutory wildlife designations including sites of special scientific interest (SSSIs) or county wildlife sites (CWSs). Collectively, there are over 600 such sites in the county. The colour of the dot represents the main type of habitat found within each site.
