Woodland Survey of Great Britain 1971-2001

The Woodland Survey of Great Britain is a unique data set, consisting of a detailed range of ecological measurements at a national scale, covering a time span of 30 years. A set of 103 woods spread across Britain were first surveyed in 1971, which were again surveyed in 2000–2003 (for convenience referred to subsequently as the “2001 survey”). Standardised methods of describing the trees, shrubs, ground flora, soils and general habitats present were used for both sets of surveys. The sample of 1648 plots spread through 103 woodland sites located across Britain makes it probably the most extensive quantitative ecological woodland survey undertaken in Britain; it is also notable for the range of sites that have been revisited after such a long interval. The data set provides a unique opportunity to explore the effects of a range of potential drivers of woodland change that operated between 1971 and 2001. The data set is available in four discrete parts, which have been assigned the following DOIs: doi:10.5285/4d93f9ac-68e3-49cf-8a41-4d02a7ead81a (Kirby et al., 2013b), doi:10.5285/d6409d40-58fe-4fa7-b7c8-71a105b965b4 (Kirby et al., 2013d), doi:10.5285/fb1e474d-456b-42a9- 9a10-a02c35af10d2 (Kirby et al., 2013c), doi:10.5285/2d023ce9-6dbe-4b4f-a0cd-34768e1455ae (Kirby et al., 2013a)

National woodland survey & native pine survey. Field handbook

Field handbook for the 2018-2022 Bunce Broadleaved Woodland Survey of Great Britain and Scottish Pinewod Surve

Common plants as indicators of habitat suitability for rare plants; quantifying the strength of the association between threatened plants and their neighbours

Rare plants are vulnerable to environmental change but easy to over-look during survey. Methods are therefore needed that can provide early warnings of population change and identify potentially suitable vegetation that could support new or previously overlooked populations. We developed an indicator species approach based on quantifying the association between rare plants across their British ecological range and their suite of more common neighbours. We combined quadrat data, targeted on six example species selected from the Botanical Society of Britain and Ireland's Threatened Plant Project (TPP), with representative survey data from across Britain. Bayes Theorem was then used to calculate the probability that the rare species would occur given the presence of an associated species that occurred at least once with the rare species in the TPP quadrats. These values can be interpreted as indicators of habitat suitability rather than expectations of species presence. Probability values for each neighbour species are calculated separately and are therefore unaffected by biased recording of other species. The method can still be applied if only a subset of species is recorded, for example, where weaker botanists record a pre-selected subset of more easily identifiable neighbour species. Disadvantages are that the method is constrained by the availability of quadrats currently targeted on rare species and results are influenced by any recording biases associated with existing quadrat data

Environment and Rural Affairs Monitoring & Modelling Programme - ERAMMP Year 1 Report 21: GMEP outstanding analysis part 2 - Revisiting trends in topsoil carbon from CS2007 to GMEP 2013-2016

New analysis was carried out to explore the reported loss of topsoil-C between 2007 and 2016 in the ‘Habitat’ category in the final GMEP report. This ‘Habitat’ category is defined as all habitats except woodlands, arable and improved grassland. The GMEP survey squares were selected using Countryside Survey protocols stratified according to Land Classes. The final GMEP survey sample from 2012-2016 consists of 7% previously surveyed Countryside Survey squares. Further analysis was needed to explore, and account for, unintended shifts in environmental variables which could have contributed to the reported topsoil carbon decline. The results indicate: 1. The reported change in the ‘Habitat’ category is driven by trends in upland habitats (median elevation of 400m). 2. In upland habitats, soil carbon is positively associated with dwarf shrub cover (particularly ericoid e.g. heather cover), Sphagnum, presence of peat, elevation and moisture conditions. 3. The coverage of dwarf shrubs was lower in GMEP than in Countryside Survey 2007, mostly due to lower cover of ericoids i.e. heather. This is consistent with decreasing soil carbon in upland habitats. Other variables (i.e. potential drivers) did not differ between surveys, or direction of change was inconsistent with reported C trends. 4. Re-analysis of Countryside Survey data (1978-2007) provides evidence that shifts over time from dwarf shrub to grass-dominated habitats are associated with a decline in topsoil carbon. 5. Overall, this suggest a potential role of ongoing vegetation change in upland habitats (i.e. conversion of dwarf shrub to grass-dominated) contributing to topsoil carbon loss. Further work is needed to: • Confirm recent vegetation change in upland habitats using independent data e.g. satellite data; • Explore relationships between specific plant species and topsoil carbon in Countryside Survey where we have a high number of true repeat samples; This work highlights the importance of the findings of the next ERAMMP survey, which will be more powerful than the combined CS-GMEP approach reported here