Early Holocene Environments Research Articles

The Bonneville Estates Rockshelter rodent fauna and changes in Late Pleistocene–Middle Holocene climates and biogeography in the Northern Bonneville Basin, USA

Excavations at Bonneville Estates Rockshelter, Nevada recovered rodent remains from stratified deposits spanning the past ca. 12,50014CyrBP (14,800calyrBP). Specimens from horizons dating to the late Pleistocene and early Holocene include species adapted to montane and moist and cool habitats, including yellow-bellied marmot (Marmota flaviventris) and bushy-tailed woodrat (Neotoma cinerea). Shortly after 900014CBP (10,200calyrBP) these mammals became locally extinct, or nearly so, taxonomic diversity declined, and the region became dominated by desert woodrats (Neotoma lepida) and other species well-adapted to xeric, low-elevation settings. The timing and nature of changes in the Bonneville Estates rodent fauna are similar to records reported from nearby Homestead and Camels Back caves and provide corroborative data on terminal Pleistocene–early Holocene environments and mammalian responses to middle Holocene desertification. Moreover, the presence of northern pocket gopher (Thomomys talpoides) at Bonneville Estates adds to a sparse regional record for that species and, similar to Homestead Cave, it appears that the ca. 950014CyrBP (10,800calyrBP) replacement of the northern pocket gopher by Botta's pocket gopher in the Great Salt Lake Desert vicinity was also in response to climate change.

Recent literature on lichens—212

Adamo, P., R. Bargagli, S. Giordano, P. Modenesi, F. Monaci, E. Pittao, V. Spagnuolo & M. Tretiach. 2007. Natural and pre-treatments induced variability in the chemical composition and morphology of lichens and mosses selected for active monitoring of airborne elements. Environmental Pollution 52(1): 11–19. [Study on Hypnum cupressiforme and Pseudevernia furfuracea from Italy. Specimens exposed in nylon bags to various treatments. ‘‘Pre-treatments remarkably changed the chemical composition of selected materials but not their surface morphology. Anyhow, water-washed and oven-dried moss shoots resulted the most suitable material for monitoring trace element deposition in two urban environments.’’] ———, S. Giordano, D. Naimo & R. Bargagli. 2008. Geochemical properties of airborne particulate matter (PM10) collected by automatic device and biomonitors in a Mediterranean urban environment. Atmospheric Environment 42(2): 346–357. [Lichens and mosses trapped air particulates, especially soil dust, in this study around urban Naples, Italy.] Alstrup, V. & U. Sochting. 2008. Hvad blev der af de danske rensdyrlaver og baegerlaver? Lavslaegten Cladonia for og nu. Vaer med til en kortlaegning! Urt 32(2): 75. [Popular note on Cladonia.] Andreev, A. A., D. J. Lubinski, A. A. Bobrov, O. Ingolfsson, S. L. Forman, P. E. Tarasov & P. Moller. 2008. Early Holocene environments on October Revolution Island, Severnaya Zemlya, Arctic Russia. Palaeogeography, Palaeoclimatology, Palaeoecology 267(1–2): 21–30. [Conditions with modern ‘‘sparse lichen-moss-grass cover’’ were established in the region about 9400 years ago as the climate became cooler and drier.] Anonymous. 2008. Secret life of lichens. The Botanics 33: 13. [A short note on a current exhibition in Edinburgh, Scotland, of specimens, photographs, and also paintings by Claire Dalby, and information on human uses as medicine and food.] Aptroot, A. 2008. Sticta alpinotropica, a new saxicolous lichen species from the alpine zone of Mt Wilhelm, Papua New Guinea. Lichenologist 40(5): 419–422. [New: S. alpinotropica sp. nov., known only from the summit region at 3900–4200 m.] ———. 2008. Lichens of St Helena and Ascension Island. Botanical Journal of the Linnean Society 158: 147–171. [Records of 225 species from St. Helena and nearly 100 from Ascension Island. New: Dermatiscum pusillum sp. nov., Dimelaena triseptata sp. nov., Dolichocarpus seawardii sp. nov., Ramalina geniculatella sp. nov., R. ketner-oostrae sp. nov., R. rigidella sp. nov., R. sanctae-helenae sp. nov. and Xanthoparmelia beccae sp. nov.] Archer, A. W. & J. A. Elix. 2008. Three new species in the Australian Graphidaceae (lichenized Ascomycota). Australasian Lichenology 63: 26–29. [New: Acanthothecis aquilonia sp. nov. (Northern Territory), Diorygma wallamanensis sp. nov. (Queensland) and Phaeographis girringunensis sp. nov. (Queensland).] Aznar, J.-C., M. Richer-Lafleche & D. Cluis. 2008. Metal contamination in the lichen Alectoria sarmentosa near the copper smelter of Murdochville, Quebec. Environmental Pollution 156(1): 76–81. [Study of heavy metals (Cu, Cd, Pb, As, Ba). ‘‘Metal concentrations and Pb isotopic ratios in the lichen Alectoria sarmentosa showed a clear spatial pattern related to a point source emission.’’] Bajpai, R. P. 2008. Quantum nature of photon signal emitted by Xanthoria parietina and its implications to biology. Indian Journal of Experimental Biology 46: 420–432. [‘‘The reproduction of photon count distributions is a credible evidence of spontaneous emission of photon signal in a quantum squeezed state for macroscopic time by the sample. It is suggested that every living system is associated with a photon field in a squeezed state. The suggestion has * The cumulative database for this series is available in searchable form on the World Wide Web at http://www.nhm.uio.no/botanisk/bot-mus/ lav/sok_rll.htm. I owe special thanks to Bill Buck for providing copies of papers by other authors, which were otherwise unavailable to me, and to the cooperating authors who send reprints or electronic versions of their works to me for inclusion in this series.

A multiproxy palaeolimnological investigation of Holocene environmental change, between c. 10 700 and 7200 years BP, at Holebudalen, southern Norway

Geochemical analyses (x-ray fluorescence, δ13C and C/N ratios) were used to reconstruct early Holocene environments (between 10685 and 7260 cal. yr BP) at a small lake near Holebudalen, southern Norway. Results show a period of increasing stability, with reduced catchment inwash (shown by titanium and potassium minerals), vegetation stabilization and increasing aquatic productivity (C/N ratios). However, periods of instability (loss on ignition (LOI) decrease) are also seen (most notably at c. 9060 cal. yr BP). Chironomid-inferred July temperature (CI-T) reconstructions show a cooling of c. 2°C (RMSEP = 1.0°C) between c. 8400 and 8000 cal. yr BP and so high-resolution (5 mm; c. 20 yr) diatom analyses were conducted between 8675 and 7830 cal. yr BP in order to further investigate this change. Between c. 8270 and 8000 cal. yr BP there were large reductions (> 50%) in the abundance of tychoplanktonic diatoms (eg, Aulacoseira species) and absolute increases in periphytic diatom communities (eg, Navicula pupula, Pinnularia mesolepta). The multiproxy analyses suggest a period of increased lake ice cover with associated reductions in turbulence during this time. Diatom flora changes are concomitant with a fall in percent LOI and increased catchment erosion at the site and other evidence of regional climatic perturbations in the early Holocene. Therefore, superimposed upon an early Holocene warming trend at Holebudalen, there are climatic perturbations, for example reflected between c. 8200 and 8000 cal. yr BP by diatom communities.

Early Holocene environments on October Revolution Island, Severnaya Zemlya,Arctic Russia

Pollen, palynomorphs, and rhizopods were studied from several < 1 m thick, peaty and silty sediment sections on southwestern October Revolution Island, Severnaya Zemlya. Six AMS radiocarbon ages from the sections show that peat accumulation started at ca. 11,500 and stopped after 9500 cal. yr BP, consistent with several previously reported 14C ages. Open steppe-like vegetation existed on the island during the late Glacial, shortly before the Pleistocene/Holocene transition. Environmental conditions on the island were most favourable for local biota during the early Holocene, ca. 11,500–9500 cal. yr BP, when tundra-like sedge-grass communities dominated the vegetation. Low shrub tundra associations with dwarf birch and willow grew in more wind-sheltered localities. The temperatures during the growing season were at least 4 °C higher than today. The Vavilov Ice Cap was at or behind its present margins. Environmental conditions in the region changed significantly ca. 9400 cal. yr BP as a result of colder and drier conditions, when vegetation became similar to the modern, sparse lichen–moss–grass cover.

Rapid change in early Holocene environments inferred from Lake Pupuke, Auckland City, New Zealand

AbstractSediment cores from Lake Pupuke in Auckland City, New Zealand, contain a high‐resolution millennial to centennial‐scale record of changing climate and catchment hydrology spanning the past ca. 10 000 years. Here, we focus on the period between 9500 ± 25 and 7000 ± 155 cal. yr BP during which grain size, diatom palaeoecology, biogenic silica concentrations, sediment elemental and carbon isotope geochemistry reflect changes in sediment sources and lake conditions, with a significant event commencing at ca. 8240 cal. yr BP, commensurate with a lowering of lake level, faster erosion rates and increased sediment influx with a duration of ca. 360 yrs. However, the changes in the lake are not reflected in the terrestrial vegetation, where the pollen record indicates that podocarp forest dominated the Auckland region, with apparent environmental stability during this part of the early Holocene. The synchronous change in most of the proxies between ca. 8240 and 7880 cal. yr BP at Lake Pupuke indicates the presence of a sustained episode of relatively low lake level and concomitant increased rate of erosion in the early Holocene that appears to be at least partly coeval with the 8200 cal. yr BP meltwater event proposed for the North Atlantic region. Copyright © 2008 John Wiley &amp; Sons, Ltd.

A 9000-Year Old Wapiti (Cervus elaphus) Skeleton from Northern Alberta, and its Implications for the Early Holocene Environment

A complete and fully articulated adult male wapiti (Cervus elaphus) skeleton was recovered from the 50 m terrace of Smoky River, near Watino, Alberta. A collagen-based date on antler gave an age of 9075 ± 305 yr BP (S-2614). The local terrace sequence features three benches, and two previously described fossil sites are placed within it. The importance of the find is that it indicates an environment at 9000 yr BP similar to the present. A brief review of local deglaciation precedes discussion of the paleontology.

Impact of extreme rainfall in the central Sudan during 1999 as a partial analogue for reconstructing early Holocene prehistoric environments

The year 1999 was an exceptionally wet year, with severe floods in China, India and Australia and very high flow in the Nile. In Sudan, the July rainfall was unusually early and heavy, and persistent rains throughout August and early September caused severe floods in much of central Sudan, including Khartoum. The synoptic conditions historically associated with extreme rainfall events in central Sudan include a warm equatorial Indian Ocean, a strong summer monsoon over both Africa and India, a northward shift of the Inter-tropical Convergence Zone earlier and further north than usual, and the presence of deep, well-developed westerly air masses accompanied by a strong Tropical Easterly Jet that allowed more moisture transport into Africa from the South Atlantic via the Congo basin, leading to very heavy precipitation in the Ethiopian uplands and the central Sudan. The intense late wet season rains in 1999 caused a major canal in the Gezira Irrigation Area to break its banks and filled normally dry depressions between dunes with water, providing a partial analogue of early Holocene environments in this region when small groups of Later Stone Age peoples occupied the sandy ridges seasonally. Global Circulation Models cannot provide such detailed local information.

Late Glacial and early Holocene environment in the middle Lahn river valley (Hessen, central-west Germany) and the local impact of early Mesolithic people?pollen and macrofossil evidence

The Late Glacial to early Holocene river valley landscape of the middle Lahntal in Hessen, central-west Germany, is reconstructed by means of pollen and macrofossil analyses. AMS 14 C dating combined with pollen, macrofossil and geomorphological mapping pro- vide a detailed chronology of the floodplain sediments of the river Lahn. Archaeological evidence for early Mesolithic settlements in the middle Lahntal is backed up by pollen and macrofossil evidence, which indicates an increase in light demanding plants, together with ones indicating nutrient-rich and disturbed environments and more macroscopic charcoal and charred pieces of pine. Different phases of human impact were dated; a first phase was dated at ca. 9,270 uncal b.p. and a second phase at ca. 9,120 uncal b.p. Comparison of the palynological data from different fluvial channel fills demonstrates that during this second phase, between ca. 9,120-8,700 uncal b.p., there were several cycles of woodland clearance. The outcome of combined archaeological, palynological and macrofossil data is discussed in terms of the impact of early Mesolithic people using fire on the vegetation during the early Holocene in the middle Lahntal.

Beringian paleoecology: results from the 1997 workshop

Much progress has been made in the various fields concerned with Beringian studies since the publication of Paleoecology of Beringia in 1982. The 1997 Beringian Paleoenvironments workshop brought together Russian, Canadian, and American scientists, and the paleoecological and archaeological presentations gave rise to 20 papers. The main points of most of these papers are summarized here, in the context of specific research topics, including (1) timing and environments associated with the Old Crow tephra in Eastern Beringia; (2) Last Interglacial environments of Eastern Beringia; (3) interstadial environments from the middle of the Last Glaciation in Beringia; (4) full glacial environments in Beringia; (5) Lateglacial environments in Beringia; (6) early Holocene environments in Beringia; (7) Late Pleistocene archaeology of Siberia; and 8) the timing, adaptations, and possible migration routes of people entering the New World.

Discussion of ‘Early Holocene environments of the River Ure near Ripon, North Yorkshire, UK’ Proceedings, Vol. 53, part 1. pp. 31–42, 2000

Discussion of ‘Early Holocene environments of the River Ure near Ripon, North Yorkshire, UK’ <i>Proceedings,</i> Vol. 53, part 1. pp. 31–42, 2000

Early Holocene environments of the River Ure near Ripon, North Yorkshire, UK

SUMMARY A sequence of peat and calcareous organic mud from the floodplain of the River Ure near Ripon has yielded pollen, plant macrofossils, Mollusca, Coleoptera, and Ostracoda which allow the first recorded reconstruction of earliest Holocene valley-floor environments for this area. A conventional radiocarbon date on a bulk sample of peat yielded an age of 9710 ± 60 bp . The palaeontological evidence suggests that the sediments accumulated in a shallow, slow moving or stagnant water body, surrounded by marshy, damp, grassland, away from contemporary channel processes, probably of a single thread river system. The climate during deposition of the sediments was no warmer than the present, and possibly slightly colder.

Lateglacial and Early Holocene environments inferred from a tufa deposit at Fyledalen, S. Sweden

A reinvestigation of a tufa deposit in Skåne, including a number of biostratigraphical methods and chronology was carried out. The tufa was formed in a paludal environment during the time period c. 9,500 to 8,000 BP. This period is characterised by exceptional low lake levels and high summer temperatures in southern Sweden. This may suggest that optimal conditions for tufa formation at the site coincided with warm and dry climate conditions, a low groundwater table, and high evaporation. During periods with colder conditions and/or higher groundwater table peat was deposited. The changes in the local environment at and around the site were inferred from the biostratigraphical records of pollen, plant macrofossils, molluscs, and insects. The results demonstrate a development from a dwarf shrub tundra during the Late-glacial, which turned to an open birch/pine woodland around 10,000 BP. At c. 9,000 BP hazel and birch were probably the dominant tree species in the woodland. The mollusc record suggests that the woodland remained relatively open until c. 8,500 BP when tree taxa such as alder, oak and elm became established in the Fyledalen valley. The site remained a marsh throughout the studied period, however, the results indicate a succession of different marsh plant communities.

Early Holocene environment on Bj�rn�ya (Svalbard) inferred from multidisciplinary lake sediment studies

Bjornoya, a small (178 km2) island situated between the mainland of Norway and southern Spitsbergen, provides the opportunity for the reconstruction of early Holocene terrestrial and limnic palaeoenvironments in the southwestern Barents Sea. The AMS 14C dating technique, geochemical, mineral magnetic, micro and macrofossil analyses were applied to sediments recovered from lake Stevatnet and the results are interpreted in terms of palaeoenvironmental conditions between 9800 and 8300 14C bp. After the disappearance of local glaciers before ca 980014C BP, the lake productivity increased rapidly at the same time as pioneer plant communities developed on soils which gradually became more stable. Insect data indicates that strong seasonal contrasts with mean July temperatures around 9°C and mean January temperatures around ?12°C prevailed between 9500 and 8300 14C BP. These high summer temperatures, possibly as much as 4-5°C higher than the present, favoured the development of a flora including Dryas and Angelica cf. archangelica. The enhanced freeze/thaw processes led to an increased erosion of minerogenic and organic material. After 8000 14C BP the temperatures may have gradually declined. The environmental reconstruction derived from our data set supports the conceptual insolation model which proposes maximum Holocene seasonality for the Northern Hemisphere at ca 9000 14C BP.

Early Holocene environment on Bjørnøya (Svalbard) inferred from multidisciplinary lake sediment studies

Bjørnøya, a small (178 km2) island situated between the mainland of Norway and southern Spitsbergen, provides the opportunity for the reconstruction of early Holocene terrestrial and limnic palaeoenvironments in the southwestern Barents Sea. The AMS 14C dating technique, geochemical, mineral magnetic, micro and macrofossil analyses were applied to sediments recovered from lake Stevatnet and the results are interpreted in terms of palaeoenvironmental conditions between 9800 and 8300 14C bp. After the disappearance of local glaciers before ca 980014C BP, the lake productivity increased rapidly at the same time as pioneer plant communities developed on soils which gradually became more stable. Insect data indicates that strong seasonal contrasts with mean July temperatures around 9°C and mean January temperatures around ?12°C prevailed between 9500 and 8300 14C BP. These high summer temperatures, possibly as much as 4-5°C higher than the present, favoured the development of a flora including Dryas and Angelica cf. archangelica. The enhanced freeze/thaw processes led to an increased erosion of minerogenic and organic material. After 8000 14C BP the temperatures may have gradually declined. The environmental reconstruction derived from our data set supports the conceptual insolation model which proposes maximum Holocene seasonality for the Northern Hemisphere at ca 9000 14C BP.

Lateglacial, early and middle holocene environments, human occupation, and resource use in the Atacama (Northern Chile)

AbstractPaleoenvironmental data from the Atacama Altiplano (21°–24°S) indicate that water, vegetation and animal resources were more abundant during lateglacial and early Holocene times than today. The rate of precipitation increased above 4000 m elevation to 400–500 mm/yr compared to the present 200 mm/yr. Dry conditions prevailed below 3500 m. Evidence of Paleoindian habitation is still missing, even though there is no evidence for environmental prohibitors during lateglacial time. The early Archaic hunters (10,820 yr B.P.‐ca. 8500 yr B.P.) inhabited the Altiplano (high Puna) and its western slope, where water was available due to higher river runoff from the Altiplano, and the resources in different elevation zones were accessible. Natural resources decreased significantly during the middle Archaic period (8500‐ca. 5000 yr B.P.). Lakes receded to today's levels, pedogenesis in the Altiplano terminated, and human activities were restricted to the most stable sites in the Río Lao and the Río Purifica catchments north of 23°S. The less stable oases south of 23°S (Salar de Atacama and Punta Negra) were abandoned. The climatic changes are best explained by shifts of the (sub)tropical circulation. © 1994 John Wiley &amp; Sons, Inc.

Late‐glacial and early Holocene environments at Pine Hill Pond, Newfoundland, Canada: evidence from pollen and diatoms

The basal 150 cm of lacustrine sediment in a 380 cm core from Pine Hill Pond, eastern Newfoundland, includes the late‐glacial and early Holocene and contains strong sedirnentological and paleoecological evidence for a climatic oscillation correlative with the Younger Dryas event. Basal late‐glacial minerogenic sediments are overlain by a silty gyttja marking the onset of organic sedimentation. An overlying unit comprising 7 cm of silty clay marks a return to mineral sedimentation prior to subsequent uninterrupted deposition of organic sediments. During this phase, the reversion from shrub tundra to a sparser herb‐shrub tundra pollen assemblage (Oxyria digyna, Arremisia) is a strong indicator of climatic deterioration at the site. The paleolimnological expression of the Younger Dryas event at this site is manifested by a sharp decrease of diatom concentrations followed by decreases in the relative frequencies of Fragilaria spp., which are largely replaced by a stratigraph‐ically restricted group of unusual benthic forms, a rise in the relative frequency of chrysophyte cysts, and a crash in Pediastrum concentrations. The nature and timing of palynological and diatom changes are interpreted in terms of both the direct and indirect consequences of climatic deterioration, as well as within the stratigraphic context of sediment lithological changes.