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Fundamental uncertainties exist in the study region about the former lowland vegetation at local scales. All existing palaeoecological results are derived from sediments of medium-to large-sized sites (8-5000 ha), which are thought to record mainly regional vegetation in their pollen content. Therefore the very small mire at Balladrum (0.05 ha) was analysed for pollen, plant-macrofossils, and charcoal and the results compared with those of previous studies in the same region. Common regional signals were detected, but also new insights for the tree species Pinus cembra (L.), Abies alba (Mill.) and Castanea sativa (Mill.). Our palaeobotanical data reveal the local dominance of the timberline species P. cembra during the Lateglacial (16500-14250 cal b.p.) at low-altitudes. For A. alba an early presence in the area is suggested by pollen data, corroborating previous high-altitudinal studies indicating the presence of glacial refugia in the region. Occasional findings of C. sativa pollen throughout the Holocene may indicate the local but very rare presence of this species in the Insubrian Southern Alps, in contrast to the conventional

Regional and national parks have been created to preserve biodiversity and quasi-natural ecosystems, but uncertainties about local environmental history hinder the assessment of important nature-conservation baselines (e.g. natural vegetation composition, role of human activities). We use pollen, plant macrofossils, microcharcoal and radiocarbon dating to reconstruct the environmental dynamics at two mires in the mountain belt of southern Switzerland (Segna and Piano). Two major vegetation changes occurred during the past 3000 years: (1) Picea abies, Abies alba and Fagus sylvatica forests developed into monospecific beech forests and (2) F. sylvatica was reduced and open land expanded. The first change occurred at AD 450 at Segna and AD 1500 at Piano, the second at AD 1600—1700 at both sites. At Segna the A. alba decline occurred during a relatively warm and dry period when local fires and human impact increased. Similarly, at Piano the shift to Fagus-dominated forests was probably induced by human impact. The final decline of F. sylvatica and expansion of open land is clearly related to an intensification of human activities at both sites. Our results suggest a pronounced sensitivity of A. alba to human disturbance in the mountain belt and show that biodiversity is positively related to land use, while human activities decisively reduced woodland diversity. In conclusion, promoting natural succession and A. alba would significantly increase woodland diversity and may significantly contribute to stabilize forests under climatic conditions significantly warmer than today. Biodiversity conservation efforts should concentrate in areas where agriculture has a long history.

Surface pollen deposition at five sites (Kichikol, Karakol, Nishneye and Verkhneye Ozero, and Bakaly) in four different forest types ( Juniperus , Picea, Juglans and mixed forests) in Kyrgyzstan have been investigated to assess the relationship between modern vegetation and pollen composition in order to calibrate the pollen representation. Vegetation surveys with an estimation of the tree-crown cover (%) were made in 10 m × 10 m plots to relate the vegetation to surface pollen of moss polsters. Correlation calculations show a close relationship between vegetation (tree-crown cover) and pollen for the Juniperus site (eg, r2 = 0.76 between crown cover and arboreal pollen, AP) and the Picea site ( r2 = 0.85), whereas the linkage is weaker at the Juglans site ( r 2 = 0.35) and in mixed forests ( r2 = 0.32). The results of the surface samples of moss polsters are compared and discussed with surface samples of lake sediments that were taken at the same locations. We use vegetational maps from around the lakes to discuss the link between vegetation and pollen at extra-local scales (800 m around the sites). These comparisons show that AP underestimates the effective tree cover around all sites, with in extreme cases densely forested areas corresponding to AP values as low as <60; 30%. We explain this finding by the prevalent background pollen load that derives from the dry lowland and slope steppes ( Artemisia, Chenopodiaceae, Poaceae). Our investigation may improve the reconstruction of Quaternary vegetation and climate history of these forest belts in Kyrgyzstan (Central Asia) on the basis of fossil pollen assemblages from mire and lake sediments. It provides new insights into the pollen reflection of forest isles (eg, on humid slopes or mountain tops) that are surrounded by continental steppes; a vegetational situation that may be used as an analogue for the conditions during the full glacial in Eurasia and Northern America.

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