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Reliable quantitative vegetation reconstructions for Europe during the Holocene are crucial to improving our understanding of landscape dynamics, making it possible to assess the past effects of environmental variables and land-use change on ecosystems and biodiversity, and mitigating their effects in the future. We present here the most spatially extensive and temporally continuous pollen-based reconstructions of plant cover in Europe (at a spatial resolution of 1° × 1°) over the Holocene (last 11.7 ka BP) using the ‘Regional Estimates of VEgetation Abundance from Large Sites’ (REVEALS) model. This study has three main aims. First, to present the most accurate and reliable generation of REVEALS reconstructions across Europe so far. This has been achieved by including a larger number of pollen records compared to former analyses, in particular from the Mediterranean area. Second, to discuss methodological issues in the quantification of past land cover by using alternative datasets of relative pollen productivities (RPPs), one of the key input parameters of REVEALS, to test model sensitivity. Finally, to validate our reconstructions with the global forest change dataset. The results suggest that the RPPs.st1 (31 taxa) dataset is best suited to producing regional vegetation cover estimates for Europe. These reconstructions offer a long-term perspective providing unique possibilities to explore spatial-temporal changes in past land cover and biodiversity.

Remote sensing technologies such as terrestrial laser scanning (TLS) and light detection and ranging (LIDAR) can now provide accurate spatial data for describing topographic patterns in landscapes and mapping the fine geometric detail of complex structures. Interdisciplinary studies using such data for characterising heritage sites are now widespread, but it is less common for data derived from these technologies to be used in an operational setting to 'engage' local people with the idea of future change. Three- dimensional landscape models using TLS and LIDAR are a powerful way of communicating climate change to lay audiences on a local level and the use of multi-scale spatial data can help to show the anticipated impacts of climate change at heritage sites. The aim of this paper is to present the results of a project designed to produce a photorealistic geospatial model of the historic quayside at Cotehele Quay, Cornwall, UK. Our central aim was to generate a spatially accurate and visually realistic three-dimensional model of the site for use in local engagement strategies. TLS and LIDAR data were collected and processed to produce a three-dimensional model. The key image processing stages included: registration to a national co-ordinate system, meshing using 3D reshaper and visualisation creation in 3DS Max. The resulting model will permit spatial consideration of the impact of management strategies at the site. The over-arching application of this method beyond the study site will provide a platform for discussion that addresses the needs of site managers and the expectations of local communities.

We present quantitative reconstructions of regional vegetation cover in north-western Europe, western Europe north of the Alps, and eastern Europe for five time windows in the Holocene [around 6k, 3k, 0.5k, 0.2k, and 0.05k calendar years before present (bp)] at a 1° × 1° spatial scale with the objective of producing vegetation descriptions suitable for climate modelling. The REVEALS model was applied on 636 pollen records from lakes and bogs to reconstruct the past cover of 25 plant taxa grouped into 10 plant-functional types and three land-cover types [evergreen trees, summer-green (deciduous) trees, and open land]. The model corrects for some of the biases in pollen percentages by using pollen productivity estimates and fall speeds of pollen, and by applying simple but robust models of pollen dispersal and deposition. The emerging patterns of tree migration and deforestation between 6k bp and modern time in the REVEALS estimates agree with our general understanding of the vegetation history of Europe based on pollen percentages. However, the degree of anthropogenic deforestation (i.e. cover of cultivated and grazing land) at 3k, 0.5k, and 0.2k bp is significantly higher than deduced from pollen percentages. This is also the case at 6k in some parts of Europe, in particular Britain and Ireland. Furthermore, the relationship between summer-green and evergreen trees, and between individual tree taxa, differs significantly when expressed as pollen percentages or as REVEALS estimates of tree cover. For instance, when Pinus is dominant over Picea as pollen percentages, Picea is dominant over Pinus as REVEALS estimates. These differences play a major role in the reconstruction of European landscapes and for the study of land cover-climate interactions, biodiversity and human resources., (© 2014 The Authors Global Change Biology Published by John Wiley & Sons Ltd.)