The Landscape Reconstruction Algorithm (LRA) with the two models REVEALS and LOVE is developed to transform pollen percentage data to vegetation cover. This paper presents the first study to evaluate LRA in a region with large topographic variations within a short distances. The REVEALS model estimates regional vegetation abundance based on pollen assemblages from large lakes (100-500 ha). Pollen surface samples from one large and 28 small lakes are used together with a combination of regionally derived pollen productivity estimates and available estimates from other regions of Europe. The results show a good relationship between REVEALS-estimated forest cover and vegetation abundance based on the CORINE land-cover data. The REVEALS results using various sets of pollen assemblages from small lakes were comparable to those using one large lake. Local vegetation abundance using the LOVE model was estimated around 26 lakes. For common taxa, such as Pinus and Poaceae, the LOVEbased estimates of plant abundance match well with the distance-weighted plant abundances based on vegetation maps. Our results indicate that the LRA approach is effective for reconstruction of long-term vegetation changes in western Norway and other regions with high topographic relief when no major gradients exist in the pollen data.

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Questions How open was the landscape prior to agriculture? Did agriculture start earlier in the south than in the north? How did the vegetation change in different regions after the introduction of agriculture? Location Coast of SW and W Norway. Methods The REVEALS (Regional Estimates of VEgetation Abundance from Large Sites) model is applied for pollen‐based vegetation reconstruction in 19 time windows over the last 9,000 years. Pollen data from 63 sites (lakes and bogs) are compiled and systematically used for data analysis so that the structure of vegetation change in space and time is captured. Results Estimated cover of selected trees, shrubs, Calluna, graminids and herbs indicate a partly open outer coast throughout the Holocene. The highest tree cover is estimated for 8,200–6,200 cal. BP. Broad‐leaved trees (Fraxinus, Quercus, Tilia and Ulmus) spread from south to north and were present in the whole region at the end of the Mesolithic (5,950 cal. BP). Larger spatial variation in tree cover and a step‐wise reduction in deciduous trees after 5,700 cal. BP is concordant with increases in open‐land taxa indicating human activity. Vegetation changes caused by agriculture are indicated in the very south from ca. 5,950 cal. BP. Distinct human‐induced vegetation changes with spatial differentiation took place from 4,200 to 1,700 cal. BP, when most of the areas earlier covered by deciduous woodland had been transformed to cultivated fields, grasslands and heathlands. Increased Poaceae cover from 1,700 cal. BP probably reflects the expansion of mown meadows in addition to pastures. Conclusions Capturing continuous changes of vegetation structure in space and time elucidates open areas along the western coast prior to the introduction of agriculture. Agriculture started earliest in the very south and spread rapidly along the whole coast prior to the Late Neolithic. Differences within the study area have existed in all time periods, reflecting different land‐use practices adapted to different natural conditions.

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Development of the cultural landscape in a village situated by the inner fjords of western Norway is investigated by pollen analysis and quantitative reconstruction methods. Pollen samples from lake sediments and a soil profile were analysed and represent different spatial scales. The Landscape Reconstruction Algorithm (LRA) is applied to a large and a small lake to convert pollen percentages from the small lake into estimated local vegetation cover in selected time periods starting from 2800 cal BC (Middle Neolithic A). This reconstruction shows that estimated forest cover has fluctuated through time, and changes in openness related to human impact are distinct from the Early Bronze Age (1800-1200 cal BC). Pollen analyses from the soil profile indicate forest clearances from the Late Neolithic (2300-1800 cal BC). Gradual intensification of farming is recognized in both pollen diagrams throughout the Bronze and Iron Ages with increasing openness and spatial differentiation in land-use practices. Presence of pollen of cereals and flax record the cultivation of these plants from the Iron Age, and intensification of land-use may have caused erosion and re-sedimentation in the lake in medieval times. To identify a possible landscape in the past, HUMPOL software has been used with the Late Neolithic as a case study. The LRA-based estimates of forest cover are supported by the HUMPOL simulations, but several solutions to the Late Neolithic landscape pattern exist. The results clearly demonstrate how implementation of LRA and HUMPOL improve the understanding of cultural landscape development.