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A limestone cave on the lower slopes of the southeastern Australian high country reveals a deep, stratified deposit dated from ca. 14,000 to 2000 cal. BP and rich in predominantly non-cultural faunal remains. Located in a sensitive ecological area between the Australian Alps and the Southern Tablelands, the site provides a valuable chronological archive for the interpretation of local environmental change using the faunal record as a proxy, in particular native rodents and other small mammals. Inferred palaeoenvironmental trends include the cessation of periglacial conditions in the surrounding ranges during the Terminal Pleistocene; a shift to warmer conditions and the establishment of forest and wetland habitats from around 13,500 to 10,000 cal. BP, with a significant decline in cold-adapted species at ca. 11,500 cal. BP and a period of significant taxon fluctuation and extinctions corresponding to a possible peak in warm and moist conditions (a 'Holocene Optimum'), beginning around 8000 cal. BP and lasting perhaps 1500 to 2000 years. Complications to the relatively steady and continuous chronostratigraphy, formed from an AMS radiocarbon sequence from sedimentary charcoal, arose from the presence of several teeth of extinct sthenurine megafauna. These were resolved with direct U-series analysis to establish their much greater antiquity and comparison of the sthenurine teeth with teeth of extant macropodids from the same deposit through fluoride absorption analysis, which also identified the megafauna teeth as anomalous to the sequence. The site provides an important case study for the interpretation of megafauna remains in stratified sedimentary deposits, especially for sites that appear to contain evidence for the co-occurrence of megafauna and humans in primary contexts. [ABSTRACT FROM AUTHOR]

Aeolian sand sheets and active dunefields preserve an ancient Holocene land surface represented by palaeosols that occur around the present ice margin in the Kangerlussuaq area, West Greenland. To determine the relation between Holocene aeolian activities and periods of soil formation, both substantially dependent on the deglaciation history, palaeosols, aeolian sand sheets and dunefields were analysed using field data, grain size analyses, optically stimulated luminescence dating and AMS 14C data in an area of about 15 km2 of the Umimmalissuaq valley. Palaeosols are developed close to the ice margin (<2 km) in fine-grained aeolian sediment (silt loam) and covered by sandy aeolian layers. Silt contents of palaeosols (partly >60 wt%) are comparable with aeolian sand sheets currently formed at greater distances (4–5 km) from the present ice margin. We propose a transport distance for fine aeolian sediments, in which the palaeosols are formed, of at least 4 km from inboard of the present ice margin. Soil formation of the palaeosols started around 2700 cal. yr b2k. Ages from the youngest parts of the palaeosols suggest a stable period of around 2400 years, allowing for pedogenesis. This period was characterised by low but constant aeolian activity. Since aeolian activity intensified after around 300 cal. yr b2k and is still resulting in active dunefields with coarse and medium sand accumulation, the ice margin must have reached its present position at that time. [ABSTRACT FROM AUTHOR]

It is predicted that future climate change will have a significant impact on the distribution of large ungulates on a continental scale. At the same time, changes in human land use on a more local scale may affect their distribution and dispersal abilities, possibly confounding the effects of climate. We analyze changes in the Holocene distribution and relative abundance of Alces alces (moose) and Cervus elaphus (red deer) skeletal remains along an overlapping range boundary of these species in western Norway. As moose and red deer are adapted to different climatic conditions we would expect the distribution of finds to reflect large-scale changes in climate. In accordance with this prediction our results indicate that red deer became the predominant ungulate in this area during the mid-Holocene warm period, c. 8000–4000 cal. BP. Contrary to this, remains of moose became even less abundant in the subsequent colder period to the present. This decrease seems tied to the spread of agriculture and deforestation, indicating the importance of considering changes in land use when predicting future changes in ungulate distribution. [ABSTRACT FROM AUTHOR]

Most of the water in the River Nile originates from monsoonal rainfall over the Ethiopian Highlands. Despite warnings of future climate change, little is known about the historical variability in this supply, particularly at annual resolution. Development of tree-ring records in this region has been limited by the occurrence of bi- or multimodal rainfall regimes, causing the development of multiple growth rings that cannot be dated with confidence. In this study, we identified annual rings in 30 Juniperus procera trees from northwest Ethiopia by dendrochronology and AMS radiocarbon dating. Carbon isotope ratios (4 series) and ring widths (73 series) were measured. The carbon isotope series did not contain strong trends possibly attributable to increased anthropogenic atmospheric CO2 concentrations or the juvenile effect. Both carbon isotope values and ring widths were strongly correlated with Blue Nile baseflow, and from composite chronology indices (r=0.75, p < 0.01), a preliminary reconstruction of Blue Nile baseflow back to AD 1836 was developed. Subsample signal strength remained above 0.85 for most of the reconstruction. Uncertainty bands were relatively narrow and the reliability of the preliminary reconstruction was confirmed by correspondence with reported years of drought and famine. The preliminary reconstruction is characterized by an exceptional decline in baseflow during the late AD 1960s. Flows recovered during the late 1990s. Additional sampling is advised to increase replication, spatial coverage and length of the preliminary reconstruction. [ABSTRACT FROM AUTHOR]

The Younger Dryas/Holocene transition (YD/H) in the sediments of Kråkenes Lake, western Norway, is well marked both lithologically and palaeobiologically at 756.5 cm in the investigated core. A series of 70 AMS radiocarbon dates on terrestrial plant macrofossils and the NaOH-soluble fraction of lake sediment was measured between 585 and 840 cm, covering the time span c. 10 440 to 7915 BP on the radiocarbon timescale. Forty-three of these dates above 760 cm were wiggle-matched against the German oak- pine dendro-calibration curve (IntCal 93) with recent corrections in both the oak and the pine sections. With an increase in age of the pine dendro-series of 200 6 20 yr, the calendar age of the YD/H lithostratigraphic boundary at Kråkenes is estimated to 11 530 [sup +40] [sub -60] cal. BP. By using a date of 9750 BP (11 170 cal. BP) on the transition between the 10 000 and 9600 14 C plateaux as a time marker, this result is compared with recent results from other archives. It is consistent with many of them, including the GRIP ice core, German pine series, Lake Gościaż, south Swedish lakes, and Baltic varves, suggesting that the Younger Dryas-Holocene transition in the North Atlantic region occurred within the range 11 500–11 600 cal. BP. [ABSTRACT FROM AUTHOR]

Holocene vegetation, climate, and fire history of the Hudson Highlands, lower Hudson Valley, south eastern New York, are inferred from AMS radiocarbon-dated pollen, plant-macrofossil and charcoal records from Sutherland (41°23'29''N, 74°02'16''W) and Spruce Ponds (41°14'22''N, 74°12'15"W). Expanding Quercus-dominated forests were invaded by Pinus strobus at 10 175 radiocarbon years before present (BP), followed by Tsuga canadensis at 9645, Fagus grandifolia at 8100, Carya at 6200, and Castanea dentata at 3600 BP; ages are averaged over two sites. Large Quercus pollen percentage and influx values are associated with continuous charcoal influx throughout the record, suggesting that fire may have played an important role in the development and maintenance of Quercus in the forest. At Sutherland Pond, a temporary decrease in fire at approximately 9500 BP apparently was a factor enabling expansion of Tsuga canadensis populations. Onset of Euroamerican agricultural practices in the region (approximately AD 1700) is well documented by rises in pollen of Ambrosia, Gramineae and Tubuliflorae and presence of Rumex and Plantago. Domestic/industrial use of Quercus, Pinus and Tsuga canadensis is also recorded by decreased percentages of these trees. Increased charcoal influx during Euroamerican settlement, particularly at Spruce Pond, may be explained by fire in connection with land clearance, wood-related industries (charcoal, iron and brick manufacturing), and operation of railroads (track fires). [ABSTRACT FROM PUBLISHER]