Deposits and Soils of the Past 130,000 Years at the Desert–Loess Transition in Northern China

1998 ◽  
Vol 50 (2) ◽  
pp. 148-156 ◽  
Author(s):  
Jimin Sun ◽  
Zhongli Ding
Keyword(s):  
Northern China ◽  
Loess Soil ◽  
Transitional Zone ◽  
Central China ◽  
Interglacial Period ◽  
Glacial Cycle ◽  
Last Interglacial ◽  
Last Glacial Period ◽  
North Central ◽  
Last Interglacial Period

The desert–loess transitional zone in north-central China has long been thought sensitive to Quaternary climatic change. However, reconstruction of Quaternary climates in this area has been hindered by incompleteness of geological sections. Here we report the analytical results of two recently found sand–loess–soil sections. Both sections have thick eolian deposits from the last interglacial–glacial cycle and can be correlated with one another. Field observations, thermoluminescence dating, and other laboratory analyses show that the last interglacial period produced three paleosols and two intercalated loess layers. Loess from the last glacial period is interbedded with three sand horizons that represent desert extension. The expansion and contraction of desert in northern China may have been forced by the east Asia monsoon.

scholarly journals Phylogeographical Structure of Liquidambar formosana Hance Revealed by Chloroplast Phylogeography and Species Distribution Models

Forests ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 858 ◽  
Author(s):  
Sun ◽  
Lin ◽  
Huang ◽  
Ye ◽  
Lai ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Genetic Differentiation ◽  
Species Distribution ◽  
Species Distribution Models ◽  
Central China ◽  
Recent Common Ancestor ◽  
Interglacial Period ◽  
Last Interglacial ◽  
Distribution Models ◽  
Last Interglacial Period

To understand the origin and evolutionary history, and the geographical and historical causes for the formation of the current distribution pattern of Lquidambar formosana Hance, we investigated the phylogeography by using chloroplasts DNA (cpDNA) non-coding sequences and species distribution models (SDM). Four cpDNA intergenic spacer regions were amplified and sequenced for 251 individuals from 25 populations covering most of its geographical range in China. A total of 20 haplotypes were recovered. The species had a high level of chloroplast genetic variation (Ht = 0.909 ± 0.0192) and a significant phylogeographical structure (genetic differentiation takes into account distances among haplotypes (Nst) = 0.730 > population differentiation that does not consider distances among haplotypes (Gst) = 0.645; p < 0.05), whereas the genetic variation within populations (Hs = 0.323 ± 0.0553) was low. The variation of haplotype mainly occurred among populations (genetic differentiation coefficient (Fst) = 0.73012). The low genetic diversity within populations may be attributed to the restricted gene flow (Nm = 0.18). The time of the most recent common ancestor for clade V mostly distributed in Southwestern China, Central China, Qinling and Dabieshan mountains was 10.30 Ma (95% Highest posterior density (HPD): 9.74–15.28) dating back to the middle Miocene, which revealed the genetic structure of L. formosana was of ancient origin. These results indicated that dramatic changes since the Miocene may have driven the ancestors of L. formosana to retreat from the high latitudes of the Northern Hemisphere to subtropical China in which the establishment and initial intensification of the Asian monsoon provided conditions for their ecological requirements. This scenario was confirmed by the fossil record. SDM results indicated there were no contraction–expansion dynamics, and there was a stable range since the last interglacial period (LIG, 130 kya). Compared with the population expansion detected by Fu’s Fs value and the mismatch distribution, we speculated the expansion time may happen before the interglacial period. Evidence supporting L. formosana was the ancient origin and table range since the last interglacial period.

scholarly journals Evidence for the Timing and Duration of the Last Interglacial Period from High-Precision Uranium-Series Ages of Corals on Tectonically Stable Coastlines

2002 ◽  
Vol 58 (1) ◽  
pp. 36-40 ◽  
Author(s):  
Daniel R. Muhs
Keyword(s):  
Sea Level ◽  
High Precision ◽  
Interglacial Period ◽  
Glacial Period ◽  
Present Level ◽  
Last Interglacial ◽  
The Bahamas ◽  
Last Glacial Period ◽  
Last Interglacial Period ◽  
The Last Glacial

AbstractThe last interglacial period has a timing and duration that can be estimated from U-series dating of emergent, coral-bearing deposits on tectonically stable coastlines. High-precision dating from Bermuda, the Bahamas, Hawaii, and Australia suggests that the last interglacial period had a sea level at least as high as present from ∼128,000 to 116,000 yr B.P. Sea level reached a near-present level more quickly after the close of the penultimate glacial period than at the close of the last glacial period and the duration of high sea level is longer than that implied by the deep-sea record.

Last glacial cycle hydrological change at Lake Tyrrell, southeast Australia

2006 ◽  
Vol 66 (1) ◽  
pp. 176-181 ◽  
Author(s):  
Tim Stone
Keyword(s):  
Interglacial Period ◽  
Silty Clay ◽  
Glacial Cycle ◽  
Last Interglacial ◽  
Southeast Australia ◽  
Last Interglacial Period ◽  
Lake Floor ◽  
Radiocarbon Chronology ◽  
High Pressure Zone ◽  
High Lake Levels

AbstractLake Tyrrell is the largest playa in the Murray Basin of southeast Australia. Optical dating of transverse dune (lunette) sediments extends the lake's radiocarbon chronology to the last interglacial period. The highest lake level was attained 131,000 ± 10,000 yr ago, forming Lake Chillingollah, a megalake that persisted until around 77,000 ± 4000 yr ago. Pedogenesis of its sandy lunette continued until buried by a silty clay lunette deflated from the lake floor 27,000 ± 2000 yr ago. The dated soil-stratigraphic units correlate with the upper Tyrrell Beds and contain evidence that humans visited the lakeshore before 27,000 yr ago. The Lake Chillingollah megalake was synchronous with very high lake levels in monsoon-dominated Australia, yet it was not influenced by tropical monsoon systems. It was filled instead by increased winter rainfall from westerly low-pressure fronts. Greater effective precipitation across Australia is evident, the result of a weakened subtropical high-pressure zone.

Eemian and early Weichselian environmental changes at the Jałówka site, NE Poland, and their correlation with marine and ice records

2021 ◽  
pp. 1-20
Author(s):  
Mirosława Kupryjanowicz ◽  
Magdalena Fiłoc ◽  
Barbara Woronko ◽  
Tomasz Mirosław Karasiewicz ◽  
Joanna Rychel ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Ice Cores ◽  
Sensu Stricto ◽  
Interglacial Period ◽  
Last Interglacial ◽  
Last Glacial Period ◽  
Ne Poland ◽  
Last Interglacial Period ◽  
Mis 5E ◽  
The Last Glacial

Abstract Vegetation changes were documented across the last interglacial period (MIS 5e, Eemian) and continuing through the older part of the last glacial period (MIS 5d–a, early Weichselian). This study was based on pollen data collected at the Jałówka site, NE Poland. Two cold oscillations appeared within warm periods during this stage of the upper Pleistocene. The older oscillation was the temporary intra–interglacial cooling at the end of the Eemian. The younger one was the intra–interstadial cooling that occurred within the oldest interstadial of the early Weichselian (MIS 5c, Brørup). This last event corresponds well to the stadial separating both the Amersfoort and Brørup sensu stricto interstadials in the Netherlands and to the Montaigu event as recognized in France. The development of a pollen sequence allows speculation as to potential correlations with Greenland ice cores and marine records. We suggest that the Eemian in NE Poland may comprise not only MIS 5e, but also a part of MIS 5d. This supposition could shed light on potential for non-synchrony in upper boundaries of the MIS 5e and terrestrial Eemian in Europe. We await the development of more precise independent dating controls to validate our theory more assiduously.

Variability in surface and deep water conditions in the nordic seas during the last interglacial period

1998 ◽  
Vol 17 (9-10) ◽  
pp. 963-985 ◽  
Author(s):  
Torben Fronval ◽  
Eystein Jansen ◽  
Haflidi Haflidason ◽  
Hans Petter Sejrup
Keyword(s):  
Deep Water ◽  
Interglacial Period ◽  
Last Interglacial ◽  
Nordic Seas ◽  
Last Interglacial Period ◽  
Water Conditions

scholarly journals How warm was Greenland during the last interglacial period?

2016 ◽  
Vol 12 (9) ◽  
pp. 1933-1948 ◽  
Author(s):  
Amaelle Landais ◽  
Valérie Masson-Delmotte ◽  
Emilie Capron ◽  
Petra M. Langebroek ◽  
Pepijn Bakker ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Ice Core ◽  
Ice Sheet ◽  
Greenland Ice Sheet ◽  
Water Isotopes ◽  
Interglacial Period ◽  
Last Interglacial ◽  
Last Interglacial Period ◽  
Ice Sheet Topography ◽  
North Greenland

Abstract. The last interglacial period (LIG, ∼ 129–116 thousand years ago) provides the most recent case study of multimillennial polar warming above the preindustrial level and a response of the Greenland and Antarctic ice sheets to this warming, as well as a test bed for climate and ice sheet models. Past changes in Greenland ice sheet thickness and surface temperature during this period were recently derived from the North Greenland Eemian Ice Drilling (NEEM) ice core records, northwest Greenland. The NEEM paradox has emerged from an estimated large local warming above the preindustrial level (7.5 ± 1.8 °C at the deposition site 126 kyr ago without correction for any overall ice sheet altitude changes between the LIG and the preindustrial period) based on water isotopes, together with limited local ice thinning, suggesting more resilience of the real Greenland ice sheet than shown in some ice sheet models. Here, we provide an independent assessment of the average LIG Greenland surface warming using ice core air isotopic composition (δ15N) and relationships between accumulation rate and temperature. The LIG surface temperature at the upstream NEEM deposition site without ice sheet altitude correction is estimated to be warmer by +8.5 ± 2.5 °C compared to the preindustrial period. This temperature estimate is consistent with the 7.5 ± 1.8 °C warming initially determined from NEEM water isotopes but at the upper end of the preindustrial period to LIG temperature difference of +5.2 ± 2.3 °C obtained at the NGRIP (North Greenland Ice Core Project) site by the same method. Climate simulations performed with present-day ice sheet topography lead in general to a warming smaller than reconstructed, but sensitivity tests show that larger amplitudes (up to 5 °C) are produced in response to prescribed changes in sea ice extent and ice sheet topography.

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