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A 11-m-long lake sediment core of a mountain lake situated at 1225 m a.s.l. in the Karkonosze Mountains (Poland) provided a unique, multi-proxy archive to reconstruct natural and human-induced environmental changes over the entire Holocene period. Pollen analyses allowed for the local and regional reconstruction of vegetation history. The chemical composition of the core and the determination of amorphous Fe and Al phases enabled to trace back soil formation in the surrounding catchment. About 11 ka ago, birch-pine and pine-birch communities started to develop in the Preboreal chronozone. Subsequently, the vegetation cover changed to Corylus-Picea-Abies + Fagus in the higher and middle mountain zones, and to Ulmus-Quercus-Carpinus in the mountain foreland and footslopes. The decline of forests that started in the 11th century because of clearing was accompanied by the expansion of grasses, both as pastures in the mountains and cereal crops in the foreland. At the same time, the mining and smelting gave rise to environmental pollution with heavy metals (Pb, Cu and Zn) at a regional scale. Combined geochemical and palynological data indicated relationships between vegetation type, sediment texture and its elemental composition. This relationship seemed to be linked to climatic conditions and surface erosion intensity. A first progressive soil-forming phase occurred from 10.9 until about 8.4 ka cal. BP. Rapid and strong soil erosion (regressive phase), related to rapid climate deterioration, occurred at about 8.4 ka cal. BP. Thereafter, continuous soil formation (progressive phase) and podzolization in the Boreal and Atlantic continued until about 1 ka BP when strong human impact (deforestation) led again to a regressive soil evolution. [ABSTRACT FROM AUTHOR]

In AD 1315, the Habsburgs fought against the Swiss Confederation at Morgarten. Since historical records are very limited, the battle has been the subject of very controversial discussions. Its location and outcome seem likely to have been influenced by the landscape and the size of the Aegeri lake, but only sparse and contradictory information are available. Numerical, semi-quantitative and relative dating techniques were applied to reconstruct the lake’s dimensions and the landscape. Results obtained from radiocarbon dating of mires (last sedimentation phase of the lake), geomorphic mapping, geoelectrics, soil maps (surface age indication) and archaeological findings were pieced together and gave an astonishingly good consensus. In the Lateglacial, the lake level was higher (750–760 m a.s.l.): because of a catastrophic event, it decreased by 25 m. About 5500 BP, the lake level was at 732 m a.s.l., and since the Roman period, it has varied between 724 and 727 m a.s.l. At the time of the battle the lake was at 726 m – that is, about 2 m higher than today. Together with the cooler climate, the greater extension of the fens and larger lake, the valley floor was wet and unpleasant. If a Habsburg army had to cross this region, they would likely have preferred to walk on a more accessible trail along the footslopes (where they probably were attacked). Precise landscape reconstruction provides new input for historical research. Details about the exact location of the battle, however, remain unclear, and the myth of the battle at Morgarten persists. [ABSTRACT FROM AUTHOR]

Subalpine and Alpine soils in Val di Sole (Trentino, Italy) have been investigated in order to reconstruct vegetation changes and human impact during the Holocene period. Archaeological findings have demonstrated that Alpine sites have been populated since pre-historical times. Humans have had a great impact on the natural landscape evolution. One of the most-used tools has been fire. The use of fire has enabled the landscape to be cleared to provide new pastures for grazing and also to allow it to be used for agricultural purposes. The 14C dating of charcoal fragments found in subalpine and Alpine soils provide information about the type of vegetation, fires, human impact and soil formation throughout the Holocene. The degree of podzolisation indicates weathering effects and provides information about the stability of the surfaces. According to our results, a quick forest expansion establishment phase must have occurred shortly after the Lateglacial around 10 500 cal. BP. Pinus sylvestris, Pinus mugo as well as Larix decidua established in the investigation area in that period. Picea abies had not yet migrated into this region at the transition to the Boreal (around 9000 cal. BP). The vegetation of the investigated area has not substantially changed during the last 10 000 years. Pinus mugo was more widespread in some areas during the Older Atlanticum, and the treeline was about 150 m higher at the end of the Younger Dryas than today. Some other sites were most probably used as pasture during the Bronze Age and later abandoned, leading to a natural reforestation. In the investigated area 13 fire events in the past 10 700 years have been recognised, and seven of them can reasonably be attributed to human origin. [ABSTRACT FROM AUTHOR]