The objectives of the habitat work are:
- To undertake detailed analysis on stock and change in the area and condition of Broad and Priority Habitats (eg. improved grassland, wet woodlands) as well as linear and point features (eg. hedges, streams, ponds, trees).
- To provide metrics that can be used in analyses, for example: habitat diversity, habitat heterogeneity, density of linear features, % land cover type, connectivity and spatial configuration of habitats, validation of remotely sensed data
- To assess and interpret changes in vegetation character across the UK.
- To explore patterns and drivers of change through integrated analysis with data from other Work Packages and external sources.
The core outputs of this work are as follows:
Analysis of land cover mapping and vegetation plot data provides:
- Estimates of stock (in hectares) and current botanical condition for 2007.
- Estimates of change in stock and botanical condition between 1998 and 2007 - and where possible, between 1990 and 1998.
- Estimates of change in stock and botanical condition along the time series 1984, 1990, 1998 and 2007.
- Helping develop the the Defra 25 YEP D1 habitat quality indicator
As with Broad Habitats (see above), analysis of land cover mapping and vegetation plot data is used, where possible, to provide estimates of change in stock and condition of Priority Habitats. Additional analyses are also be undertaken to explicitly pick out shifts in the balance of indicator species and other attributes currently used in Common Standards Monitoring.
The Priority Habitats on which the Survey has reported include
- Blanket Bog
- Upland Heath
- Lowland Heath
- Beech Woodland
- Lowland Mixed Deciduous Woodland
- Upland Mixed Ash Woodland
- Upland Oak
- Wet Woodlands
- Lowland Acid Grassland
- Upland Calcareous Grassland
- Lowland Calcareous Grassland
Linear and Point Features
The study provides:
- Estimates of stock in kilometres for 2007.
- Estimates of change in stock between 1998 and 2007 - and where possible, between 1990 and 1998.
- Estimates of change in stock along the time series 1984, 1990, 1998 and 2007.
Exploring Patterns and Drivers of Change
The 2007 Survey addressed a number of key questions about the role of land-use and environmental factors in driving ecological changes.
- Has botanical condition in the arable and horticultural Broad Habitat changed between 1998 and 2007? If further changes in food plant abundance for lowland farmland birds have occurred, can they be attributed to changes in set-aside uptake and the presence of new field margins?
- Is the eutrophication signal found in the 2000 Survey still detectable in low-productivity vegetation types? Is the signal correlated with changes in soil variables and in turn correlated with changing land-cover, agricultural productivity and deposition?
- Is there any evidence of differences in trajectory of change across the time-series between designated and undesignated countryside?
- If independent spatially accurate data on agri-environment scheme uptake is available, can we establish a baseline characterisation of habitat condition and stock in and outside of agreement land?
- Is reform of the Common Agricultural Policy (CAP) resulting in changes in agricultural land use that impact on biodiversity?
- Is it possible to detect signals of climate change in the habitat datasets?
- Can we test key ecological theories such as the area-heterogeneity trade-off at multiple scales using fine-scaled mapping data and plant species richness?