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To understand the role of the East Asian summer monsoon (EASM) and the East Asian winter monsoon (EAWM) on the hydroclimate in northern Taiwan, a multiproxy study has been conducted. This study aims to achieve its goal by using micro-XRF data of Ti and sulfur (S), carbon isotopic compositions (δ13C) along with elemental concentrations of carbon (C), nitrogen (N) and S, and diatom analyses in the sediment core extracted from the Dream Lake (DL; 25°10′01.9″ N, 121°33′36.0″ E and elevation = 588 m above sea level), northern Taiwan. The radiocarbon dates revealed that the DL core covered the time interval from 4.5 to 0.4 cal kyr BP. The current records revealed wetter phases during 4.5–3.0 cal kyr BP, 2.0–1.7 cal kyr BP, and 1.0–0.4 cal kyr BP, characterized by the dominance of C3 plants in the DL catchment, increased runoff, and higher lake levels. Drier climates observed in the current study during 3.0–2.0 cal kyr BP and 1.7–1.0 cal kyr BP, marked by a reduction in C3 plants, decreased runoff, and lower lake levels. The northern Taiwan climate during the late Holocene was observed to be regulated by the interplay of EASM and EAWM. The wet climate conditions during 4.5–3.0 were due to the La Niña-like conditions, which led to a strong EASM resulting in high precipitation conditions. The dry climate conditions during 3.0–2.0 cal kyr BP have coincided with El Niño-like conditions during 3.0–2.4 cal kyr BP and a subsequently strong EAWM during 2.4–2.0 cal kyr BP. Both situations led to a reduction in precipitation in the region. Unlike the time frame from 4.5 to 3.0 cal kyr BP, wet climate conditions during 2.0–1.7 and 1.0–0.4 cal kyr BP have coincided with weak EAWM conditions, which led to an increase in precipitation in northern Taiwan. The dry climate noticed between 1.7 and 1.0 cal kyr BP appeared to be the impact of both El Niño-like conditions and strong EAWM. [ABSTRACT FROM AUTHOR]

Proxy-based paleoclimate reconstructions in the central Zagros region suggest the occurrence of several climatic events during the Last Glacial Maximum (LGM) to Holocene. The central Zagros region is situated in a unique transition zone between mid-latitude temperate climate in the north and sub-tropical arid climate in the south and was affected in different climatic periods by the strengthening and weakening of the Indian monsoons, the inter tropical convergence belt, the westerlies and the low-pressure systems of the Mediterranean and the Atlantic Ocean. Our results suggest that a transition occurred from dry and dusty conditions during the LGM to a relatively wetter period with higher carbon accumulation rates in the Early Holocene (11600 cal yr BP). Between 30000 and 19000 cal yr BP, cold and dry climatic conditions with the dominance of Amaranthaceae and semi-desert steppe prevailed in the region. High values of magnetic susceptibility, decrease in organic matter, and increase in allogenic elements indicate the presence of cold and dry climate in the region during the LGM. The Holocene was characterized by relatively less dry and dusty conditions, which is consistent with orbital changes in insolation that affected much of the northern hemisphere. Numerous episodes of high aeolian input spanning a few decades to millennia are prevalent during the Holocene. Dry events identified in the area occurred at 10200, 9200, 8200, 5200, 4200, 3200, 2200, and 1600 cal yr BP. Also Younger Dryas, occurred in the region 12300-11600 years ago, and it was cold and dry period with a decrease amount of pollen and increase in dust. [ABSTRACT FROM AUTHOR]

The sedimentary infill of the Quibas karstic site (Early Pleistocene, southern Spain) represents the only continuous succession with remains of continental vertebrates in Europe from pre-Jaramillo to post-Jaramillo age. The Quibas site, with a significant paleontological record, is dated between 1.1 and 0.9 Ma and offers a unique opportunity to carry out a paleoclimatic reconstruction of the time period immediately after the arrival of the first humans to western Europe. For this reason, defining the dominant sedimentary processes in the different stratigraphic units and the associated paleoenvironment is essential. The Quibas site is made up of two karstic features with two stratigraphic sequences: Quibas-Cueva, containing six lithostratigraphic units, and Quibas-Sima, which contains seven lithostratigraphic units. The detailed description and analyses of the stratigraphic sections have allowed the characterization of various autochthonous and allochthonous facies of cave deposits. Paleoclimatic proxies, inferred from sedimentological analyses, reveal a record of several alternating humid and arid phases resulting from the Early Pleistocene glacial-interglacial cycles, allowing correlation to the marine oxygen isotope record. The lowermost units (pre-Jaramillo) were deposited during a long-lasting interglacial, correlated to MIS 33–31. It was followed by an increase in aridity in the intermediate units of Quibas-Sima and uppermost unit of Quibas-Cueva (Jaramillo), revealing the beginning of a glacial period at the start of the Jaramillo subchron (1 Ma), which can be correlated to MIS 30. The upper Jaramillo and post-Jaramillo units suggest these were deposited in alternating periods of aridity and humid conditions, although less humid than the pre-Jaramillo period, probably representing the MIS 29 interglacial, the MIS 28 glacial and the MIS 27 interglacial. [ABSTRACT FROM AUTHOR]

Semi-subterranean house occupation in the southern Columbia Plateau of Western North America was episodic over the latter half of the Holocene. Several analyses of radiocarbon chronologies for house features have emphasized environmental change as a primary catalyst of shifts in subsistence strategies and house settlement. Our analysis incorporates summed probability distributions of radiocarbon dates for house occupations, climatic conditions, and evidence of conflict to assess the relationship among the three variables. Climate change is outlined using previously published proxy data. Results of our analysis indicate that climate had a strong influence on the settlement systems of the southern Columbia Plateau. Along with the direct influence of climate on resource availability, conflict became more frequent when house communities became larger. Developing a greater understanding of the cause and effect, and timing of environmental and social changes will ultimately require more robust datasets for house occupations, simulations of demographic trajectories, and higher resolution temporal and spatial models of climate change on the Columbia Plateau. [ABSTRACT FROM AUTHOR]

The possibility of a collapse (or marked weakening) of the Atlantic Meridional Overturning Circulation (AMOC) within a few centuries boosted the interest of the scientific community on the responses of different compartments of the climate system to past AMOC collapses (or marked weakening). The most recent examples of such periods are Heinrich Stadial 1 (HS1,18-15 ka BP; near-collapsed AMOC) and the Younger Dryas (YD, 12.9-11.7 ka BP; markedly weakened AMOC). Here, we present data from elemental ratios, spectral reflectance, organic biomarkers, sea surface temperatures and planktonic foraminiferal assemblage from two marine sediment cores recovered from the western tropical South Atlantic Ocean spanning the last ca. 20 kyr. The recovered sediments record the responses of eastern tropical South American hydroclimate, western tropical South Atlantic productivity and sea surface temperatures to changes in AMOC strength associated with HS1 and the YD. Our data show that both periods were characterized by wetter conditions over eastern tropical South America associated with increased continental runoff compared to the Last Glacial Maximum. High sea surface temperatures during HS1 and the YD are in line with marked AMOC decreases that led to heat accumulation in the surface layer of the western South Atlantic Ocean, facilitating increased precipitation over eastern tropical South America. Our data demonstrate for the first time that intense runoff during HS1, and hence nutrient transfer to the ocean, affected the pelagic ecosystem, likely increasing primary productivity in the otherwise oligotrophic western tropical South Atlantic Ocean. Our study demonstrates a tight coupling between marine and terrestrial processes in the eastern South American realm during periods of strong climate instability. [ABSTRACT FROM AUTHOR]

In soils of the temperate zone, there is an increase in the magnetic susceptibility χ of an upper layer compared to χ C of parent rocks. The difference between χ and χ C characterizes the magnetic "enhancement" Δχ, which is usually considered as associated with mean annual precipitation (MAP), allowing the reconstruction of MAP of the past from Δχ values of paleosols. which is widely enough used. However, in regions with a wide MAP range, non-monotonic dependence of Δχ on MAP is observed, making this reconstruction ambiguous. To construct climatic functions for reconstructing the past climate, we subdivided the south of European Russia into three regions, where climatic functions such as MAP(Δχ) of modern soils are monotonic and close to linear. These regions are relatively dry, humid, and semi-humid cold. We considered an extended set of climatic features including potential evapotranspiration (PET), actual evapotranspiration (AET), water deficit (WD = PET–AET), moisture index (MI = MAP/PET), an index of De Martonne (IDM = MAP/(MAT+10), where MAT is the mean annual temperature). The links of Δχ with MAP were positive in dry and negative in humid and semi-humid cold where they are weaker, but there were closer links with temperature-dependent WD and PET. Reliable (with R 2 > 0.7) climatic functions were constructed for dry and semi-humid cold, but such reliable functions were absent in humid part. Since the differences in soil - forming material, it is necessary to identify some parameter to characterize lithological factors. For this reason, we include in consideration median grain sizes (lgSz) in soil profiles and total iron (Fet) to obtain some explanations for the results. Although the use of Δχ, lgSz and Fe t together made the climatic functions more reliable (R 2 ∼ 0.8), but Δχ played the main role, while lgSz and Fe t were not always significant. Based on the obtained data, it appears possible to provide a more detailed subdivision of paleoecological periods in the Late Holocene for the steppe and forest-steppe zones of the Eastern Europe. Taking into account the diversity of soil conditions in different regions, equations using soil profile MS enhancement to reconstruct rainfall should be used locally and regionally, taking into account the identified limitations and eliminating the possible ambiguity of reconstructions. [ABSTRACT FROM AUTHOR]

Regional responses to Bond events during the Holocene are important components of paleoclimate and environmental change research. However, there are few records of Bond events during the Holocene in arid central Asia; such events remain poorly understood in this region because of a lack of continuous and high-resolution deposits. Here, new magnetic and grain-size records from a loess sediment sequence located on the southern margin of the Tarim Basin (TB) are provided, which exhibit strengthened dust activity at 9.6–9.4, 8.2–7.8, and 5.5–5.2 ka BP. These periods of strengthened dust activity during the early and middle Holocene in the TB are consistent with Bond events revealed from ice raft detritus in the North Atlantic, and abrupt climate events recorded by loess deposits, lake deposits, and stalagmite oxygen isotopes in arid central Asia and east Asia. We suggest that a delayed seasonal jet transition, resulting from the intensification and southward-shift of the westerly jet during Bond events, plays a key role in creating conditions in the TB that favor strengthened dust activity. [ABSTRACT FROM AUTHOR]

Boron (B) isotope has been widely used in marine sediments to reconstruct paleoclimate evolution history. However, due to the relatively complex continental deposition environment, complicated fractionation process and controls of multi-processes on the δ11B variations of terrestrial sediments, the application of B isotope in terrestrial sediments and its indicative significance are limited and controversial. Here we conducted systematic B isotope and chemical composition studies on extracted evaporite, carbonate and silicate phases of sediments from a well-studied Quaternary deep drilling core (SG-1) from the Qaidam Basin, NE Tibetan Plateau, to explore the respective geochemical behavior of the B isotope in different phases of sediments and their respective implications. The results indicate that B in the evaporite phase of the SG-1 sediments is primarily derived from ion co-precipitated minerals instead of fluid inclusions. The δ11B variations in the carbonate and silicate phases possess different implications. The δ11B carbonate could serve as a potential paleo-salinity indicator, and the δ11B silicate could be a possible indicator to reflect the chemical weathering history of the catchment. Our systematic B isotope analysis explores the influences of different processes on the B isotope components of terrestrial sediments and decomposes the respective implication of B isotope in different phases of sediments. It can therefore provide important reference significance for future B isotope in terrestrial sediments and its application in paleoclimate study. [ABSTRACT FROM AUTHOR]

Diatom, pollen, silicoflagellate, and biogenic opal analyses from a 155 cm-long gravity core from Pioneer Seamount, offshore Santa Cruz, California (PS1410-06 GC, latitude 37.3°N, longitude 123.4°W, water depth 2165 m) are compiled for the last ~11,300 years and compared with those of ODP 1019 and TN062-O550 from northern California. The relative abundance record of the subtropical diatom Fragilariopsis doliolus has similar bimodal Holocene patterns in all three cores, suggesting that sea surface temperatures (SST) were lower during the middle part of the Holocene than they were during the later and earlier parts. The relative abundance of coastal redwood (Sequoia sempervirens) pollen, a proxy for fog and coastal upwelling, displays stepwise increases in ODP 1019 and TN062-O550 between ~ 4000 and 3000 cal yr. BP, but its relative abundance in PS1410-06 GC increases gradually throughout the past 10,200 yr without any major steps. Similarly, biogenic silica (opal) displays stepwise increases at ~3600 and 2900 cal yr. BP in ODP 1019 and TN062-O550, respectively, whereas opal increases more gradually in PS1410-06 GC during the past 10,100 yr with relatively minor steps at ~3100 and ~2600 cal yr. BP. Together, coastal redwood and opal argue for a more gradual late Holocene increase in coastal upwelling along the coast of central California compared with that off northern California, where onshore-offshore gradients are more distinct. [ABSTRACT FROM AUTHOR]

Eurasian loess-paleosol sequences provide continuous records of global change in mid-latitude Northern Eurasia. The loess-paleosol sequence of West Siberia located in the central part of the mid-latitude Eurasian loess belt extending from West Europe to Yakutia is an outstanding paleoclimate archive in Northern Asia. The stratigraphy has been best documented on the left bank of the Ob River, in the so-called Ob Loess Plateau. This study focuses on the stratigraphy of the most complete Middle-Late Pleistocene loess-paleosol sequence at the Belovo section. The suggested high-resolution model of the Belovo Late Pleistocene stratigraphy is based on magnetic and sedimentological proxies and is correlated with other Eurasian loess records and with the global marine δ18O stratigraphy. The enviromagnetic signal at Belovo Loess-paleosol sequences shows a transitional pattern comparable with both typical Eurasian loess magnetic records. Detailed paleopedological interpretations of the magnetic and sedimentological data from the Belovo section have important implications for appropriate linking different Late Pleistocene climates and environments of other the well-known Eurasian loess provinces. [ABSTRACT FROM AUTHOR]

To investigate the paleoclimate and paleoenvironment of central Italy during the Middle Pleistocene, we analyzed the carbon and oxygen stable isotope composition of the carbonate component of sequential enamel samples from twenty-four rhinoceros (Stephanorhinus spp.) teeth. The samples come from two key archeological and paleontological sites located in the Molise region: Isernia La Pineta (ILP; ∼600 ka) and Guado San Nicola (GSN; ∼400 ka). Carbon isotope ratios of enamel from both ILP and GSN indicate feeding in a pure C 3 ecosystem that consisted predominantly of woodlands and/or mesic C 3 grasslands with the possible sparse presence of closed canopy forests at or near ILP ∼600 ka. The average (± 1 σ) enamel δ13C for ILP (−13.6 ± 0.6‰) is lower than that for GSN (−12.1 ± 0.4‰), suggesting higher mean annual precipitation and lesser aridity ∼600 vs. ∼400 ka. Average intra-tooth variability in enamel δ13C from both sites is low (∼1‰), likely indicating seasonally uniform diets, plant carbon isotope compositions, and precipitation amounts. However, the low intra-tooth variability in enamel δ13C may also reflect amplitude attenuation of the isotopic signal of the plants into tooth enamel. With respect to oxygen isotopes, the average (± 1 σ) enamel δ18O for ILP (24.2 ± 0.7‰) is slightly lower than that for GSN (25.0 ± 0.7‰), likely reflecting the higher elevation of ILP as well as lesser aridity and/or slightly lower mean annual temperature in the region ∼600 vs. ∼400 ka. The δ18O values of meteoric precipitation (∼-7‰) calculated from enamel compositions are indistinguishable from the modern values, suggesting that mean annual temperatures were broadly similar to today (∼13°C). Both sites exhibit a moderate average intra-tooth variability in enamel δ18O (∼2‰), likely indicating a temperature seasonality similar or slightly decreased relative to today. The temperate climate and the increase in aridity that occurred sometime between ∼600 and ∼400 ka were potentially important factors for the human colonization of the Italian peninsula and for the cultural and behavioral evolution of the early hominins during the Middle Pleistocene. [ABSTRACT FROM AUTHOR]

Multiproxy analyses performed at the Krosinko site in the Warsaw–Berlin ice marginal valley have provided data that characterize the depositional conditions, the paleofluvial regime, and the paleoclimate and help reconstruct the paleo-environment at a time of significant sediment (alluvium) accumulation (starting in central Poland ca. 45 ka BP). The sedimentological study, including sand-grain morphology and micromorphology analyses, reveals the presence at Krosinko of a meandering river and of a braided river during the Eemian (MIS 5e) and Upper Pleniweichselian (MIS 2), respectively. The fluvial regime changed over time, from low-energy, through high-energy, to low-energy, as documented by the differently formed sedimentary units A–D (vertical sedimentary succession from base to top: sandy silt, sand, gravelly sand, and sand). Sedimentary unit A and the lower part of unit B were accumulated in the Eemian interglacial (MIS 5e) by the low-energy meandering river. The high-energy fluvial environment during the Weichselian is associated with long, intense sediment transport, organic remains, and flints, as confirmed by taphonomic studies on conifer cones (Picea cf. abies) and wood remains (Juniperus). The river operated under distinct environmental conditions. First, during the accumulation of the upper part of unit B and unit C, there was a strong influence of freezing and aeolian weathering, which weakened significantly over time (unit D). This in turn indicates a change in climate from periglacial (upper part of unit B and unit C), when we also document the presence of permafrost in the subsurface or relatively deep seasonal frost, to temperate (unit D). With warming in the Holocene (MIS 1), an oxbow lake developed in Krosinko, the presence of which is recorded by peat. [ABSTRACT FROM AUTHOR]

As an important region of desertification in China, the Qinghai-Tibetan Plateau (QTP) has attracted great attention. However, the study of land desertification history at the millennia-scale on the interior plateau is grossly inadequate. In a severely and rapidly desertifying area in the Beiluhe Basin on the interior QTP, grain-size distributions, sand particle morphologies, and 7 available optically stimulated luminescence (OSL) ages of sand sediment from two fixed aeolian dunes were obtained by several laboratory tests. Combining these results with plateau paleoclimate and contemporary aeolian sand activities in several adjacent regions, two phases of evident enhanced aeolian sand accumulation corresponding to desert expansion over the past 1500 years in the study region were identified. The first enhanced phase (850–700 a B.P.) might have been closely related to suitable trapping of denser vegetation cover and degradation of permafrost on the QTP as a consequence of warm and wet climates. Reactivation of local older sediments caused by cold and dry climates might have been responsible for the second enhanced phase (1400–1200 a B.P.). Permafrost plays an important role in aeolian sand accumulation and desertification on the QTP. However, expansion (or degradation) of permafrost has not always prevented (or promoted) aeolian desertification development on the QTP since the Last Glaciation Maximum (LGM, 21–14–12 ka B.P.). The effects of permafrost on aeolian desertification are governed by numerous factors such as preceding and current climate conditions, locations of permafrost and aeolian sand activity, and trap conditions due to vegetation and topography. [ABSTRACT FROM AUTHOR]

The 230Th dating (238U–234U–230Th dating method) has become one of the most important dating methods for Quaternary research. However, the 230Th/232Th ratio of 4.4 ± 2.2ⅹ10−6 is widely used for age correction in 230Th dating method. Here, we collected active speleothems with exactly known age and zero-year-old calcium carbonate from caves and dated them by 230Th dating. Our data indicated that the initial 230Th/232Th ratio can be one order of magnitude higher than the ratio of 4.4 ± 2.2 × 10−6. High initial 230Th/232Th ratio may result in false and comparatively old calculated age than the real age of young samples with low 238U concentration. So, the accurate initial 230Th/232Th ratio of active speleothem deposited in the same cave, instead of the general initial 230Th/232Th ratio, is essential for the precise age correction of young speleothem samples of low 238U concentration. Finally, we proposed a procedure to correlate modern observation and speleothem based paleoclimate reconstruction, on the basis of precise 230Th age which corrected by the true initial 230Th/232Th ratio. [ABSTRACT FROM AUTHOR]

Micromorphological investigations of loess-paleosol sequence offer the potential for understanding pedogenic and paleoclimate change at the microscopic scale. However, the micromorphological study is comparatively scarce in the south Qinling Mountains, China. Here, micromorphological analysis (coarse particles, pedofeatures and voids) in conjunction with physicochemical indexes of pedogenesis (i.e., clay content, CaCO 3 and Fe 2 O 3) were carried out from two Holocene loess profiles in the upper Hanjiang River. These results show that: (i) Paleosol is considered as strongly-developed soils on basis of much finer and rounder particles, channels, more reddish color and abundant illuvial clay coatings; (ii) Lessivage (clay formation, eluviation and illuviation), intensive carbonate eluviation and rubification were identified as the major pedogenic processes of paleosol; (iii) Comparative study with Chinese Loess Plateau (CLP) indicates that loess deposits in the south Qinling Mountains experienced a much stronger pedogenesis as evidenced by multiple generations of illuvial clay and almost completely eluviation of carbonate, which implies a warmer and wetter paleoclimate in the subtropical monsoon zone. The pedogenic differences across the Qingling Mountains are mainly controlled by regional paleoclimatic differences and provide a good response to monsoon climate change in the East Asian. [ABSTRACT FROM AUTHOR]

Recent interest in modern climate change has stimulated extensive scientific study into past societal responses to climate variability. However, examining climate change and society as a historical narrative drawing upon politics, economics, and settlement patterns does not provide a direct link between climate and society. Given that most inhabitants of the premodern world engaged in agriculture and/or pastoralism, examining chronological correlations between climate and foodways, not as a historical narrative but as a longterm socioenvironmental process, has the potential to identify direct societal adaptations to a changing environment. From South Greece there is evidence for drier conditions at the end of the Late Bronze Age. Is the disappearance of writing, art, and many known settlements at the end of the Bronze Age an example of collapse in the face of inability to adapt to climate change? This is a difficult question to answer given the coarse resolution of many of our archaeological and climatic datasets. Settlement faunal records suggest that food production systems became increasingly homogenous in Late Bronze Age Greece, potentially due to an elite control over various production systems that promoted intensification of certain products. However, in the first millennium B.C.E., animal husbandry, specifically, and food production systems, more broadly, became more heterogenous, and a proportional increase in goats in areas with less rainfall was likely an adaptive response to the drier climate. This paper examines the adaptive relationship between foodways and climate and argues for a process driven approach when explaining social responses to ancient climate change. [ABSTRACT FROM AUTHOR]

The relationship between surface pollen and modern vegetation is an important criterion for interpreting fossil pollen spectra in reconstructing of paleovegetation and the paleoenvironment. A total of 438 surface pollen samples were collected from the Junggar Basin, Tianshan and Altai Mountains, and other areas in northern Xinjiang, China. Surface pollen assemblages were divided into five horizontal pollen zones: alpine and subalpine meadows, mountain forests, steppes, deserts, and wetlands. A high abundance of tree pollen was detected in the Altai and Tianshan Mountains, primarily originating from conifers such as Picea and Larix. Desert steppe vegetation was predominant on both sides of the central Junggar Basin, with significant amounts of pollen from Ephedra , Chenopodiaceae, and Artemisia. The geographic distribution of the pollen source sites was analyzed using ArcGIS. R -value, Pearson correlation analysis, and principal component analysis were used to determine the distribution and central region for each of the main pollen taxa identified. Picea pollen at abundance levels above 30% indicated the existence of local spruce forests, as observed in the Tianshan and Altai mountains' conifer forests. A considerable amount of Betula pollen was observed in the intrazonal vegetation dominated by Betula , such as wetlands and river valleys, indicating the distribution of birch forests in the local vegetation. The pollen taxa of Ephedra , Chenopodiaceae, and Artemisia was over-represented across all investigated areas. These data may improve the accuracy and reliability of vegetation and climate reconstructions based on pollen data; furthermore, our information provides a framework for predicting future environmental trends. [Display omitted] • Modern pollen reflects well the characteristics of vegetation in northern Xinjiang. • The geographic distribution of typical pollen taxa was analyzed using ArcGIS. • Tree pollen were mainly distributed in the Altay and Tianshan Mountains. • Abundant Betula pollen in intrazonal wetlands indicated the growth of birch. [ABSTRACT FROM AUTHOR]

The quantitative reconstructions of past climate changes on the Tibetan Plateau derived from glacial record based on glacier-climate models have been reported in existing researches. However, compared with low altitude areas and the vast majority parts of the Tibetan Plateau, modeled paleoclimate conditions from glacial record are still lack. This hampers the advancing understanding of regional climate–glacier interactions. The glacial history of Burhan Budai Shan provides an opportunity to reconstruct paleoclimate conditions since the penultimate glacial cycle. We applied a coupled mass balance and ice flow model to estimate paleoclimate during the early Holocene, MIS3 and penultimate glacial cycle. On the southern model domain, the model results suggested that the temperature drops ranged from -0.5～0.1 °C and 2.4～3.9 °C with precipitation being 140～200% and 30～100% of present during the MIS3 and penultimate glacial cycle, respectively. On the northern model domain, the early Holocene temperature was lower than present levels by 0.5～1.5 °C which presented separate evidence for the early Holocene precipitation being 80～150% of modern values. The model results in the model domain are generally consistent with other climate records on the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

The eastern North American Arctic has a complex 5000-year prehistory, during which many human population movements occurred over great distances. Archaeologists have interpreted these movements as resulting from many factors, however the effects of climate change are often hypothesized as primary drivers that can "push" human groups to leave some regions, or "pull" them to move to others. Here, we examine climate change at the regional scale over the Common Era using Arctic paleoclimate data derived from a wide suite of biological proxies and geochemical tracers. We consider available statistical composites of high resolution (sub-decadal) paleo-temperature reconstructions for the Arctic region, as well as local-scale reconstructions at century or sub-century scale resolution in three focal regions of archaeological significance relevant to population movements: Victoria Island, Foxe Basin/Baffin Island, and the High Arctic (Ellesmere Island/Northwestern Greenland). We emphasize the two most widespread, though variable, climate change events characteristic of this period: the Medieval Climatic Anomaly and Little Ice Age in the second millennium AD; we also evaluate the evidence for the Roman Warm Period and Dark Ages Cold Period in the first millennium AD, as context for later events. We integrate information on the timing and magnitude of these events across the Canadian Arctic Archipelago, and assess the degree to which they coincide with current understanding of major population movements, with particular emphasis on three migration episodes. First, the expansion of Late Dorset Paleo-Inuit to the Central and High Arctic beginning in the late first millennium AD is plausibly linked to warming temperatures of the MCA. Second, the migration of Thule Inuit from Alaska to the Eastern Arctic beginning ca AD 1250 is not linked to warmer temperatures as previously hypothesized, and is therefore more likely related to social factors in Alaska. Third, the abandonment of northern regions and new settlement of southern regions by Inuit in the mid-second millennium AD is likely linked to a combination of cooling climate and increasing availability of European trade goods. Together, these three case studies indicate that linkages between climate change and migration are complex, variable, and mediated through social and economic factors. [ABSTRACT FROM AUTHOR]

Ebi (or Aibi) Lake is located in southwestern Junggar Basin in the Xinjiang Uygur Autonomous Region of northwestern China. In this study, we collected fossil pollen samples from the top 11.4 m of an Ebi core to reconstruct climate variability during the Late Quaternary. Results of a principal component analysis (PCA) of terrestrial pollen taxa from the Ebi core showed that four principal components explained 90.9% of the total variance. The chronology of the core section was determined based on five 14C dates obtained by accelerator mass spectrometry (AMS) and five dates obtained by optically stimulated luminescence (OSL). The studied section encompassed the Late Quaternary periods (37.6–3.6 cal ka). Environmental changes in Ebi Lake were divided into four stages based on significant pollen assemblage changes. From 37.6 to 34.5 cal ka, climate conditions were warm and dry. The climate became warmer and wetter between 34.5 and 28 cal ka and then deteriorated to cold and dry during 28 to 9 cal ka. High temperatures and dry conditions during the Early Holocene (11–9 cal ka) may have caused forest fires. From 9 to 3.6 cal ka, the climate was warm and wet; however, pollen data indicate that it was relatively drier between 6 and 4 cal ka. Available soil moisture during MIS 3 stage was less than that of the Holocene Optimum especially during 37.6–34.5 cal ka. [ABSTRACT FROM AUTHOR]

In this study, we present the results of independent component analysis (ICA) of previously published Lake Van data covering the last 250 kyr BP, to shed light on the precipitation and temperature regime in eastern Anatolia. The data processed were the element intensities of Ca, Fe, K, Mn, and Si analyzed by XRF core scanner; concentrations of TOC and CaCO 3 content; and B* (color reflectance) from the Ahlat Ridge sediment record. Our analysis is based on application of ICA on the data by changing the initial random unit vector several times and clustering possible independent components through average-link agglomeration. As components extracted by ICA do not have a hierarchy, mutual information, which is a measure of information content between two random variables, is used as a measure of similarity by which to select candidate components. As a result, we argue, the independent component (Van-IC8), which shows the highest similarity to the Greenland δ 18 O record and visually similar to other regional temperature indicating data, can be read as a proxy for temperature variability. We also assert that the independent component (Van-IC7) which has the highest similarity to B* and visually similar to other regional precipitation proxies, and with the lake level reconstruction from another sediment profile from Lake Van is a proxy of precipitation variability across the region. Our results show that the region's temperature approximately maps onto global records, i.e. warm during interglacials and cold during stadials. However, the precipitation proxy reveals that the region was not dry, or at least as wet as it is today, during the end of the MIS 6 and the LGM. The MIS 5e/c and Holocene were characterized by a wet period followed by dry intervals and Dansgaard/Oeschger events are characterized as being warm and wet. [ABSTRACT FROM AUTHOR]

XRF core scanning has evolved to become a standard analytical technique for the rapid assessment of elemental, density and textural variations in a wide range of sediments and other materials, with applications ranging from palaeoceanography, paleoclimatology, geology, and environmental forensics to environmental protection. In general, scanning provides rapid, non-destructive acquisition of elemental and textural variations at sub-millimetre resolution for a wide range of materials. Numerous procedural adaptations have been developed for the growing number of applications, such as analyses of unconsolidated, water-rich sediments, powdered soil samples, or resin bags. Here, practical expertise and guidance from the Itrax community, gained over 15 years, is presented that should provide insights for new and experienced users. [ABSTRACT FROM AUTHOR]

Abstract Climate fluctuations of the Quaternary caused radical changes in distribution of tree species and resulted in large-scale range shifts, population contractions and expansions. Scots pine (Pinus sylvestris L.) a widely distributed conifer of the boreal regions underwent spatio-temporal changes, which shaped the modern-day genetic structure and phylogeographic pattern of the species. By applying independent approaches, including molecular genetic data and historical climate models we aimed to describe demography and past distribution patterns of Scots pine populations from the highly fragmented southern periphery, the Carpathians and the Pannonian Basin. We used Approximate Bayesian Computation (ABC) approach based on nuclear microsatellite markers (nSSRs) and Maximum Entropy distribution modelling (MaxEnt) with temperature- and precipitation-related bioclimatic data. ABC results indicated that from an ancestral Scots pine population two genetic lineages have diverged that in the Mid-Pleistocene due to the favourable climatic conditions underwent population expansion leading to an admixture event. The outcome of the hindcasting confirmed the expansion that leaded to the admixture event revealed by the ABC analysis. This can be dated to the Late Glacial period (14,160–11,800 yrs BP), in which widespread distribution of Scots pine in accordance with palynological proxies was detected. Predictions for the Mid-Holocene period have shown large-scale reduction in distribution of Scots pine and low probability of its occurrence, leading to disjunction and population fragmentation. [ABSTRACT FROM AUTHOR]

Abstract According to the findings of a complex radiocarbon dated sedimentological, geochemical, anthracological, phytolite, malacological study implemented on an open 1036 cm wind-blown sand, loess, sandy loess and fossil soils profile of western part of brickyard at Katymár village in Hungary. Increased boreal mixed-leaved forest steppe and temperate grassland cover characterized the interstadials in the SE Great Hungarian Plain during the terminal phase of MIS3 stage and MIS2 stage. These interstadials correlate well with the Dansgaard-Oeschger (DO) interstadials 8, 7, 6, 5, 4, 3, 2 and the post LGM warm interval (DO1) seen in the Greenland ice core oxygen isotope records. Intervening cold phases, on the other hand, their start correlating with Heinrich event 1, 2, 3, 4 and the LGM. These data overall confirm that millennial scale climate variability during MIS3 and MIS2 stages had profound effect on the terrestrial ecosystems in the continental interior of SE Europe leading to periodic mixed-leaved boreal forest steppe within mosaic structure expansions in the interstadias and cold steppe, taiga and tundra like spots mosaic and mixed vegetation expansion in the stadial phases. 1400–1500 year long drier interstadial and humid, extended vegetation covered stadial periods interchanged at Katymár sequence, therefore the vegetation and fauna development was different from the Atlantic and Central European schemes and inferred an independent local and regional South Carpathian Basin trend. [ABSTRACT FROM AUTHOR]

Abstract Early studies of loess in New Zealand were concentrated in the South Island, in particular in the province of Canterbury, on Banks Peninsula and at Timaru. Five important scholars can be identified and studied: J von Haast, F.W. Hutton, J. Hardcastle, L.J. Wild and R.Speight. They cover a period from first recording, in 1878, into the nineteen forties. They all recognised the importance of the Southern Alps in the production of loess material by mountain glaciers though Hutton and Wild took a somewhat controversial view that the final deposition was by some marine process. It can be argued though, that of the five, Hardcastle made the most significant contribution with the first observations of loess as a 'climate register' at Timaru in 1890 and was the first scholar to detail the role of glaciers in the production of loess material. The loess recorded the changes in climate for the Quaternary Era. Hardcastle, in effect, invented the science of palaeoclimatology; he should be recognised as a significant climatological pioneer. [ABSTRACT FROM AUTHOR]

Abstract The paleosol unit S5S1, which corresponds to Marine Isotope Stage (MIS) 13, is the most prominent paleosol layer in the central Chinese Loess Plateau (CLP). S5S1 has extremely high magnetic susceptibility, but it remains uncertain whether this is related to climate or to time (the duration of pedogenesis) due to the anomalously low loess deposition rate. To address this question, we investigate the iron mineralogical properties of the S5S1 paleosol at the Xifeng loess section located in the central CLP. We compare the results of S5S1 with other paleosol units, yielding additional insights into the CLP climatic changes during MIS-13. The results show that magnetic enhancement of S5S1 paleosol is stronger than that of the other paleosol units, which is mainly governed by pedogenic produce fine-grained ferrimagnetic minerals; the maximum value of the goethite concentration compared with hematite in the S5S1 paleosol unit is markedly higher than those in the other paleosol units. The prolonged period of pedogenesis is not main controlling factor that leads to the magnetic enhancement of S5S1 because the concentration of SD/SP has hardly changed compared with other paleosols as with the increasing of magnetic susceptibility. Changes in the ratio of pedogenic hematite to goethite, as well as in magnetic enhancement, indicate that the S5S1 paleosol developed under extremely humid conditions. This extremely humid climate is a main cause that leads to the extremely high magnetic susceptibility. [ABSTRACT FROM AUTHOR]

Abstract We used indexes of soil moisture content to reconstruct water balance and vegetation type during the development of the palaeosol S 4 of the loess-palaeosol sequence in the Xi'an area of China. Goethite–Fe-Mn concretions were found within S 4 from field survey and laboratory analyses, and their presence is used as an indicator of soil moisture content and the depth distribution of groundwater. From a comparison of the goethite–Fe-Mn concretions, weathered-leached loess layer, and the vertical migration distance of CaCO 3 between various sections in the Xi'an region, we infer a subtropical climate with annual average temperature 15–16 °C and annual average precipitation of 900–1000 mm during the development of S 4. At that time, unlike today, the Qinling Mountains were not the boundary between subtropical and temperate climatic regions. Our results show that the depth distribution of soil gravitational water in the Xi'an region reached 3.3 m; the average soil moisture content within the 0–3.3 m depth range was ∼25%, after water consumption by evapotranspiration; and the soil moisture content within the goethite–Fe-Mn concretion layer was close to saturation, at ∼48%. Soil moisture was abundant and the water balance was positive and a large amount of moisture was supplied to the groundwater each year, which was conducive for the development of forest vegetation. [ABSTRACT FROM AUTHOR]

Several temperature-sensitive paleoclimate proxies, including tree rings, stalagmites, and historical documents, were employed to derive regional temperature signals for the period 1779–1985 via principal component analysis (PCA). The PCA series was significantly correlated with gridded temperature datasets for Northeast China, the Korean Peninsula, and part of Japan. Based on statistical correlation between the PCA series and observed temperature records, we regionally reconstructed May–August temperature variations for 1779 to 2009. The reconstruction explained 53.4% of the variance in observed summer temperature during the instrumental period. Intervals with persistent decadal warm and cold periods in the past 231 years were detected. The results suggest that, of the past 231 years, the past half century suffered unprecedented warming in North-Central China, which may be related to increasing human activities since the Anthropocene epoch. [ABSTRACT FROM AUTHOR]

Tree ring plays an important role in deciphering the paleoclimatic signals. Although tree-ring width (TRW) has obvious advantages in studying the hydroclimatic history in the middle-high latitudes, it has certain limitation in hydroclimatic signal extraction in the tropical to subtropical areas, which greatly limits our fully understanding about the hydroclimatic history in these areas. In this work, tree-ring δ 18 O (δ 18 O tree ) records from five independent tree-ring cores were measured and a composite δ 18 O tree record (1939–2014) was developed in Guilin, subtropical southwest China. No “juvenile effect” existed in this δ 18 O tree record and no relationship was found between δ 18 O tree and TRW. Correlation analysis with the climatic parameters demonstrated that the δ 18 O tree record significantly ( p < 0.01) and negatively correlated with all the hydroclimatic parameters during the growing season (e.g. April–October precipitation, August–October relative humidity and April–November standardized precipitation–evapotranspiration index), while it only positively correlated with the August–September mean temperature ( p < 0.05). At high frequency, the above relationships were greatly strengthened. Compared with the temperature-limited TRW in Guilin and other areas of subtropical China, δ 18 O tree was a better choice for hydroclimatic reconstruction. Moreover, the δ 18 O tree record in Guilin showed high consistency with other moisture-sensitive δ 18 O tree records in a large area of central-southeastern China. Analysis revealed that both large-scale circulation system (e.g. Indian summer monsoon, ENSO, westerlies) and local weather system significantly influenced the growing-season hydroclimatic variation in the study area. This study provides great potential for extracting hydroclimatic information from longer-living trees in subtropical China. [ABSTRACT FROM AUTHOR]

This study carried out in Lake Tuzla in northeast Cappadocia (Central Anatolia- Kayseri-Palas Plain) aimed primarily to determine changes in paleovegetation of mid-to late-Holocene in the vicinity of Lake Tuzla and factors affecting these changes. A secondary objective was to determine paleoenvironmental conditions during the settlement period of Kültepe (Karum-Kanis), an important archaeological site in the region. Fossil pollen analysis was carried out on a sediment core 337 cm long representing the period from the present day extending back to 5080 ± 30 years. Changes in paleoclimatic conditions and paleovegetation were identified. From changes in the vegetation, the climatic changes determined were dry in the periods 3200-3000 BP, 2050–1450 BP, and 1120-850 BP; and humidity in the periods 1400-1115 BP and 1400–1700 BP. Alterations to the vegetation structure between 3230 and 1155 BP reveal the effects of the Beyşehir Occupation Phase (BOP). According to Lake Tuzla data, the effect of BOP was relatively less than that of Lake Nar. After the end of BOP, pine forests grew in the area around Lake Tuzla. The vegetation consisted of Pinus and Quercus in AP (arboreal pollen) and Artemisia , Amaranthaceae and Poaceae in NAP (non-arboreal pollen). The density of Artemisia , Amaranthaceae and Poaceae taxa suggests that steppe vegetation was dominant in the surroundings of Lake Tuzla. [ABSTRACT FROM AUTHOR]

Climate variability is a well-known phenomenon and has been frequently, though complex, linked to solar forcing on different time scales. The importance of solar forcing related climate variability is crucial in our understanding of paleoclimate and future climate changes, as well as building climate models. Here in, we present the late Holocene (last ca 1400) climate records from Lake Salda in SW Anatolia using high-resolution micro X-ray Fluorescence (μ-XRF), magnetic susceptibility (MS), stable isotopes (δ 13 C and δ 18 O) and TOC-TIC measurements. The age model is constructed by using radionuclide ( 210 Pb, 137 Cs and 14 C) dating methods. The lake's high-resolution multiproxy results revealed lake water level fluctuations associated with humid and dry spells during the last 1400 years. Periods of higher lake levels are consistent with solar maxima in total solar irradiance and vice versa. Moreover, the Lake Salda records clearly show dry Dark Ages Cold Period (DACP), humid Medieval Climatic Anomaly (MCA), dry Little Ice Age (LIA), and humid Modern Warm Period (MoWP). These records suggest that the solar forcing, through its influence on the atmospheric circulation, is the main mechanism of climate change during the DACP, MCA, LIA and MoWP in this region. [ABSTRACT FROM AUTHOR]

This study discusses the detailed chronobiostratigraphic history and paleoenvironmental features in the Quaternary period at Lake İznik (NW Turkey) based on fossil ascidian spicules and nannofossil records. New ascidian spicule data and nannofossils were identified in three lake bottom mud cores, K-1, K-2, and K-3, and in the muddy sediments of two drilled samples, SK-1 and SK-2. In the samples, eleven fossil ascidian spicule species, including two new species, were recorded: Bonetia acuta Varol & Houghton, Bonetia brevis Varol & Houghton, Bonetia quasitruncata Varol & Houghton, Micrascidites vulgaris Deflandre & Deflandre-Rigaud, M. gothicus sp. nov., Monniotia aciformis Varol & Houghton, M. fasciculata Varol & Houghton, M. minutula sp. nov., Rigaudia multiradiata Varol & Houghton, and R. praecisa Varol & Houghton. Ascidian spicules in the core muds probably released from the Didemnum species ( i.e. , D. candidum ) were compared to Holocene nannofossil data, such as Alisphaera sp., Coronosphaera mediterranea , Emiliania huxleyi , small Gephyrocapsa spp., and Scyphosphaera spp., representing the NN21 Emiliania huxleyi zone. Drilling core sediments also include the same ascidian fossils, and also one nannofossil species, Gephyrocapsa oceanica , indicating the NN21 zone of upper Pleistocene stage, as found in sample SK-1. Based on the ascidian spicules and nannofossil records of the coring/drilled muds of Lake İznik was marine, as an inlet or lagoon connected to the modern Gulf of Gemlik, during the Pleistocene to Upper Holocene. It was likely separated from the Marmara Sea and turned into a freshwater lake after the upper Holocene. [ABSTRACT FROM AUTHOR]

We present the multi-proxy records of centennial scale climate and environmental changes over the last 3.5 ka from a varved sediment core in Lake Van, eastern Turkey. The multi-proxy analyses include ostracod counts, μ-XRF elemental, total organic (TOC) and inorganic carbon, C-N elemental and stable isotopes. For the age model of the core, we use radionuclide ( 210 Pb and 137 Cs) analysis and varve counting. Large differences between Accelerator Mass Spectrometry (AMS) radiocarbon dates from TOC and varve ages indicate reservoir ages of 1.2–3.8 ka calBP. Average sedimentation rate for the last 170 years (top 75 mm of the core) ranges between 0.42 and 0.54 mm/yr according to 210 Pb dating. Multi-proxy parameters show that Lake Van experienced more arid conditions during the 3.5–1.6 Ka calBP than those during the last 1.6 ka BP. 16 periods of alternating cold/dry and warm/wet intervals with 100–350 years duration are observed over the last 3.5 ka. The Lake Van climate records are conformable with the Lake Nar and the Sofular speleothem records as well as the European historical climate periods including Roman Warm Period (RWP), Dark Age Cold Period (DACP), Medieval Warm Period (MWP) and Little Ice Age (LIA), indicating teleconnections with the North Atlantic system. Human influence is reflected by high detrital influx in the last 700 years. [ABSTRACT FROM AUTHOR]

High-resolution seismic reflection profiles and core analyses in Lake Hazar provide a detailed record of the lake level fluctuations and the robust chronology of paleoclimatic events of the Eastern Anatolia during the late Pleistocene to Holocene. The earlier period of Marine Isotope Stage 3 (MIS-3) prior to 48 cal ka BP was accompanied by considerable lake level drop below −95 m, whereas the lake level increase during the later period (ca. 48-29 cal ka BP) gave rise to deposition of a transgressive unit with typical of aggradational architecture in the seismic reflection profiles. High climate variability with the Greenland interstadials and stadials (Dansgard-Oeschger and Heinrich events) in Lake Hazar are sensitively recorded in the core sediments by using multi-proxy analyses. Adjustment of seismic units correlating with the radiocarbon-dated chronostratigraphic units in the studied cores implies that the early Marine Isotope Stage 2 (MIS-2) is marked by an another lowstand lake level existed at ca. −90 m during 29–23 cal ka BP. In comparision to MIS-3 stage, the multi-proxy analyses reveal a general dry evaporative condition during most of the Last Glacial Maximum. In Lake Hazar, the maximum humidity in the late glacial period existed during 14.9–13.5 cal ka BP. The existence of a hiatus in the sedimentary record is documented in the seismic data that coincides with the cold and dry Younger Dryas period, implying a remarkable lake level drop. The multi-proxy records of the Holocene sediments reveal that a maximum precipitation in the early Holocene period prevailed during 10.1–9.3 cal ka BP, leading water level rise in the lake. In Lake Hazar, the middle Holocene until 4.9 cal ka BP is represented by highly climate variations, indicating a series of shorter wet and longer dry climate periods. The late Holocene is accompanied by lake level rises under a general wet climate condition that was interrupted by short dry climate intervals during 3.7–3.3 cal ka BP, 2.8–2.6 cal ka BP and 2.1–1.8 cal ka BP. [ABSTRACT FROM AUTHOR]

The Central Anatolian Region (CAR), being a high orogenic plateau (1000–1500 masl) is located between the Pontides in the north and the Taurides in the south, has a semi-arid climate. Significant changes occurred in vegetation and human activities within the CAR due to climate changes during the Holocene. On the other hand, the anthropogenic effect on vegetation in the region which has experienced intensive settlements since the beginning of the Neolithic period, has become the destiny of the region. In this study, the pollen data obtained from Lake Engir are presented to show the effect of the late Holocene vegetation, climate changes and anthropogenic effect on vegetation around the archaeological settlement of Kültepe. The archaeological settlement of Kültepe which is an important Assyrian trade colony, dated between 3000 BC and 1000 BP, is located in the north of Kayseri in the CAR. Within the scope of this study, aiming to shed light on the paleo-environmental conditions during this settlement period, the pollen data characterizing the period between 2300 and 300 BP were obtained from core samples collected from Lake Engir near Kültepe. A total of 71 taxa were identified from palynological analysis of core samples. Significant changes in paleoclimatic conditions and vegetation were determined from these analysis. Significant changes were experienced between the years 1930-1820, 1850-1760, 1760-1650 and 1650-1470 BP in vegetation. The climate changes indicated by vegetation changes were determined as wet and dry periods. Wet periods took place between the years 2300-1850, 1760-1650, 1400-1150 and 920-300 BP, and dry periods took place in the years 1850-1760 and 1650-1400 and 1150-920 BP. The Beyşehir Occupation Phase representing an intensive agricultural period occurred between the years 1850-1400 BP, and this period suddenly ended at 1400 BP. This situation is related to the abandonment of the land with regard to the Arab raids on Anatolia between the years 1400-1150 BP. The pine forests developed again in this period. Agriculture and animal husbandry activities in which cereal farming was dominant started since 1050 BP. [ABSTRACT FROM AUTHOR]

Although numerous studies concerning the Holocene climate of the southern Iberian Peninsula were accomplished within the last few decades, the climate history of this region is still poorly understood. Various studies deal with a combination of proxies, which are neither easy to compare nor is their connection easy to explain, e.g., due to spatial patterns and time transgression. Within this study, the suitability of the lacustrine sediments from the Laguna Salada (Andalucía region, southern Spain) as a paleoclimate archive is investigated. The lake sediments were evaluated using a multi-proxy approach including sedimentological, mineralogical, geochemical and biological analyses. The sediments reflect the evolution of the lake from pre-Medieval times onwards and Characeae as well as Ostracod analyses give an indication of paleosalinity. Moreover does the geochemical composition provide profound information concerning changes of elemental and mineralogical composition. Nevertheless, a robust, high-resolution chronology could not be achieved owed to the scarcity of material available for radiocarbon dating and contamination problems. Furthermore, poor preservation of pollen restricted the reconstruction of vegetation history, which could have complemented important information concerning climatic changes and human activity. [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. The author has plagiarized part of a paper that had already appeared in the International Journal of Evolutionary Biology, 2012 (2012), 574851 (https://doi.org/10.1155/2012/574851). One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process. [ABSTRACT FROM AUTHOR]

The landscape evolution of the Sant’Eufemia Plain (Calabria, Italy) in the last 8300 years was reconstructed through integration of pollen data and archaeological evidence within a well-defined paleoenvironmental and chronostratigraphical framework. Pollen analysis of a 24-m core showed that a dense floodplain forest characterized the landscape from ca. 8300 up to ca. 2300 yr cal BP, when human impact becomes evident through intense deforestation, cultivation and fires. Due to the high density of the forest canopy in the plain, few signs of human presence are recorded by pollen in prehistoric and protohistoric periods despite the occurrence of settlements from the Neolithic to the Iron Age. In concurrence with the reduction of wet environments in the plain and the surrounding foothills, major urban centers and villas developed during the Graeco-Roman period, entailing considerable environmental impact. Clear signs of deforestation, recorded through a general reduction of tree taxa, were connected to timber production and trade during the Roman period, as also attested by historical sources. Intensive olive cultivation started in the Early Medieval period, in agreement with other data from central and southern Italy, suggesting that olive oil consumption during the Roman period was not connected to large-scale local production. The Holocene history of this landscape shows that the location of settlements from the Neolithic onward was strongly influenced by the environment, which led people to select more stable, well-drained areas, such as relicts of inactive depositional landforms within or around the plain. [ABSTRACT FROM AUTHOR]

Microfaunal remains are commonly used as palaeoenvironmental proxies and have been proposed as a means to identify relative ages of Late Quaternary deposits through biostratigraphy (i.e., utilising ‘Mammal Assemblage Zones’). However, assemblages of faunal remains can include a diverse range of taxa which are often difficult to distinguish using morphological aspects of the surviving bones, particularly when diagnostic features are eroded or missing due to fragmentation. Here we investigate the application of a recently developed method of species identification by collagen fingerprinting to arvicoline rodents (voles and lemmings), the dominant mammalian taxonomic group present at the Late Pleistocene site of Pin Hole Cave, Creswell Crags U.K., which is currently the designated British type locality for the Pin Hole Mammal Assemblage Zone (Oxygen Isotope Stage 3) fauna. We also further explore the potential for studying collagen decay rate via deamidations, and their applicability across the species boundary, in terms of its use for relative ageing of remains. Our results demonstrate the ease with which some taxa can be objectively distinguished to genus (e.g. Microtus from Myodes and Lemmus from Dicrostonyx ) and in some cases species (e.g., M. gregalis from M. oeconomus ), but that the potential for relative ageing is complicated by a range of taphonomic factors. The results highlight the potential for this new technique in much larger-scale palaeoenvironmental studies investigating temporal changes in vertebrate biodiversity. [ABSTRACT FROM AUTHOR]

South Africa contains a wealth of palaeokarst deposits that have yielded hominin fossils and Early Stone Age archaeology. Despite the complex nature of deposition within many of these caves there has been a dearth of detailed geoarchaeological studies undertaken on these sites. Many sites in South Africa have been interpreted using an overly simplistic Member System based on simplified sedimentological attributes, rather than chronostratigrahic units. Many of the defined Members thus identify different, but contemporary geological processes occurring in the caves. This has caused serious confusion in reconstructing the life histories of palaeocaves and the ages of the fossil remains interned within them. It is critical to uncover new sites that have not been extensively altered by decades of data collection and destructive mining techniques employed early in their discovery. Although unmined sites present their own problems with regards to extensive colluvium cover and access to fossil-bearing units, analysing strata that is found in-situ enhances overall confidence of interpretations drawn. A wealth of geoarchaeological and 3D visualisation techniques can now be employed to aid in the understanding of cave life histories, as well as their excavation. In this paper we present the first attempt to integrate and publish data from a range of such methods on South African fossil bearing palaeokarst using the newly discovered Drimolen Makondo deposit as a case study. This includes the use of ground penetrating radar, 3D visualisation through photogrammetry and multi-scale 3D scanning, micromophology and petrography, palaeomagnetism, mineral magnetism, synchrotron radiation, electron spin resonance, uranium-lead dating and biochronology. Our analysis has allowed us to successfully uncover the full extent of this new ∼2.61 Ma fossil bearing palaeokarst deposit and to visualise and interpret its chronostratigraphy. [ABSTRACT FROM AUTHOR]

For decades, it has been unclear as to how the world's first cities, in southern Mesopotamia, not only arose in a fluvial environment but also how this environment changed. This paper seeks to understand the long-term fluvial history of the region around Uruk, a major early city, in relation to water-human interactions. This paper applies geomorphological, historical and archaeological approaches and reveals that the Uruk region in southern Mesopotamia had been under the influence of freshwater fluvial environment since the early Holocene. It further demonstrates how canals and long-term human activities since the mid Holocene have been superimposed on the natural river channel patterns. Fieldwork has been conducted to ground-truth features identified applying remote sensing techniques. Five sediment cores were analysed to elucidate palaeoenvironmental changes. Radiocarbon ages for organic samples suggest that the oldest sediment layers, at a depth of 12.5 m, are from the Early Holocene, while results from diatom analyses imply that the whole sediment column was deposited in a freshwater environment. Intensive networks of palaeochannels and archaeological sites within the study area have been reconstructed and these networks have been divided into four different time intervals based on changes in channel courses. The first is from the early 4th to the late 1st millennium BCE; the second is from the late 1st millennium BCE to the middle 2nd millennium CE; the third lasted from after the Islamic period until the 1980s; the fourth is from the 1980s until the present. Key results include evidence for freshwater environments and favourable settlement conditions had already formed by the 8th millennium BCE. The favourable settlement environment resulted in stable (long-lived) canals between the 4th millennium BCE and 1st millennium CE. A significant settlement and irrigation expansion occurred in the early 1st millennium CE. Major abandonment ensued in the late 1st millennium CE and lasted until the mid 2nd millennium CE. [ABSTRACT FROM AUTHOR]

The Rozprza stronghold functioned as a seat of a noble family since at least the early14 th century AD in the form of the motte-and-bailey residence. The remains of the residence are situated in the central part of mid-Luciąża River valley, on the river terrace remnant adjoining a strongly expanding floodplain. The situation and state of preservation give a unique opportunity to conduct research that explain the construction process, detailed history of the medieval moat and palaeoenvironmental reconstruction of the valley floor. Radiocarbon and dendrochronological dating and analysis of artefacts confirmed 14th century age of the moat. Organic deposits (gyttja, peat and organic mud) of moat fill allowed for a set of multiproxy analyses based on sediment cores. The research results indicate shallow water with brief episodes of in-wash in the first stage (13 th -14th c. AD), followed by a transformation into telmatic habitat in the second phase of the moat development from 16 th -17th c. AD. The deposition of overbank alluvium took place within the moat ditch system as late as the 18th and/or 19th c. AD. We studied the development of this moat environment in the context of valley floor changes. [ABSTRACT FROM AUTHOR]

We establish the three-dimensional stratigraphic architecture of the Taipei Basin and its spatiotemporal palaeoenvironmental development during the past 50 kyr by analysing 36 borehole cores and 177 age dates. We calculate the rates of basin subsidence from the borehole data at depths where radiocarbon age dates are available. Our results indicate that, during the eustatic sea level falling period (35–20 ka), low rates of sediment supply and/or rapid basin subsidence controlled sedimentation, leading to a change in the depositional environment from gravelly braided rivers, through sandy braided rivers, to meandering rivers with falling eustatic sea level. During the early stage of eustatic sea level rise (∼20–10.2 ka), balanced rates of sediment supply, eustasy and basin subsidence maintained the meandering river environment. Rapid sea level rise led to the initial appearance of estuarine facies at ∼10.2 ka and widened the distribution of the estuarine environment after 8.5 ka; however, the coeval phases of rapid basin subsidence ∼10.6–10.2 ka and 9–8.5 ka promoted the first appearance and widening of the estuary, respectively. After 7 ka, when the eustatic sea level and rate of basin subsidence remained relatively stable, sufficient sediment supply gradually infilled the estuary. The established stratigraphy improves our understanding of the factors controlling stratigraphic development in marine-influenced inland half grabens, specifically in the Taipei Basin with high rates of sediment supply. Accommodation space in the Taipei Basin was governed by eustatic fluctuations with modulations by basin subsidence and sediment supply since the last glacial period. [ABSTRACT FROM AUTHOR]

The paper of Milana et al. (2016) presented interesting palaeoclimatic results related to the evolution of a foredune ridge plain of a regressive (prograded) barrier in southern Brazil. Unfortunately, they presented an evolutionary model for a type of wave-dominated delta, and not for a coastal barrier. By not classifying the regressive barrier of Cassino properly, the authors made a succession of incorrect interpretations, such as the nature of littoral drift directions during the progradation of the ridge plain. By using their delta model, they obtained opposite directions than the actual ones. In challenging the barrier model of the area, which has been well-established for more than 50 years, they should have more fully discussed the differences between deltas and barrier systems, in a manner which would have given support to their interpretations. [ABSTRACT FROM AUTHOR]

Birds have been considered good climate indicators in Pleistocene environmental reconstructions, due to their current distribution and specific ecological requirements. They have been analyzed as associations and in some cases also as indicator species for the climate during the Late Pleistocene, which is a stage that shows strong climatic fluctuations. In this work we present an analysis of the relative abundances of thirty-three of these indicator species of Aves in Late Pleistocene Western European sites, in order to characterize the avian associations and bird species behavior, and also shed light on the corresponding ecosystems of the different geographical areas of Europe during this stage. Our analysis reveals four main groups of sites, which correspond mainly to the current biome distribution. Nevertheless, the position of some sites in the analysis is markedly different, revealing a drift southward of the Eurosiberian-Mediterranean boundary during the Late Pleistocene. The results also allow us to analyze the behavior of the various species, whose distributions seem to be controlled by the predominant vegetation in each area more than by the temperature. The different associations of each area suggest that Central Europe was forested or at least point to the presence of forest patches in this area at the end of the Pleistocene. They also reveal the need for avian association analysis instead of the use of isolated bird species to produce landscape and climate reconstructions. [ABSTRACT FROM AUTHOR]

Los Batanes C4 is a cave-site in the Spanish Pyrenees, the minimum sediment calendar age was determined to be 15,234 ± 223 cal BP by radiocarbon dating. The cave opens on the northern bank of an eastern tributary of the River Gállego, at an altitude of 1025 m. The small vertebrates recorded are mainly bats, in order of abundance Rhinolophus euryale , R. ferrumequinum , Myotis sp. and Miniopterus schreibersii . The association suggests that at the time of the accumulation the climate was reasonably similar to the current climate; we situate it within a period of local retreat of the ice-cover in the Gállego Valley during the Lateglacial. This is the highest record of these species of Rhinolophus in the Iberian Quaternary, showing that the R. euryale altitudinal range was similar to its extant range during the favourable periods of the Lateglacial. This could indicate that this taxon was relatively quick in spreading into higher regions whenever climate conditions allowed it. [ABSTRACT FROM AUTHOR]

Research into the surface soil pollen found within different sediments constitutes one important part of modern palynological analysis; however, such studies have not been carried out in the arid regions of Asia. In order to determine the main characteristics of the pollen assemblages of different sediments, 26 surface pollen samples were selected from five different sedimentary environments (sand dune, alluvial fan, wetland, floodplain and riverbed) found in three transverse sections in the middle reaches of the Heihe River. The results show that the five different sediment types have significantly different pollen assemblages: (1) sand dune: Chenopodiaceae - Artemisia - Nitraria - Poaceae; (2) alluvial fan: Nitraria - Chenopodiaceae; (3) wetland: Poaceae - Typhaceae - Chenopodiaceae – Artemisia ; (4) floodplain: Picea - Cyperaceae - Chenopodiaceae - Artemisia - Asteraceae; and (5) riverbed: Picea - Cyperaceae - Polypodiaceae - Chenopodiaceae – Artemisia . The auxiliary functions derived from analyses of the principal components also indicates a significant difference between pollen assemblages for the five different sediment types. This established the veracity of these particular pollen assemblages representing these five different sedimentary environments, thereby improving the reliability of our research results. Those results provide the fundamental information required for any reconstruction of the region's paleovegetation and paleoclimate based on the pollen records found in different sedimentary environments. [ABSTRACT FROM AUTHOR]

Vegetation and climate during later part of Pleistocene to major part of Holocene (∼16.6–3.5 ka) has been reconstructed based on the palynological and magnetic susceptibility proxies from an exposed section of lacustrine deposit at Rukti, Sangla valley, Kinnaur, western Himalaya. Study shows that along with the general tree line succession to higher altitudes since early Holocene, the area has also captured the major climatic events of late Pleistocene to early-mid Holocene time. The area exhibits a continuation of mixed conifer - broadleaved forest at least since ∼16.6 ka with intermittent phases of expansions of broadleaved tree taxa especially Oaks ( Quercus ) or invasion of conifers especially Pine ( Pinus ) with an increase (moist) or decrease (dry) of Indian Summer Monsoon (ISM) respectively. This is also supported by the variations in the magnetic susceptibility values. The climate was warm and moist during ∼16.6 ka and changed to cool ∼13.3 ka, followed by increasing ISM since ∼11.5 ka. Distinct spike in the magnetic susceptibility values between ∼8.7 and ∼7.8 ka could correspond to global 8.2 ka cool event thus indicating strengthening of westerly influence and low evaporation. Subsequent warm conditions could be generalized by the advancement of Birch ( Betula ) line to higher altitude following the resultant retreat of the glacial body. Study has put forth the potential of such Himalayan sites to uncover the major climatic events of global correlation captured by various proxies within a region. [ABSTRACT FROM AUTHOR]

Geological investigations in the southern part of the Polish-Belarusian cross-border area were focused on correlation of main Middle Pleistocene stratigraphic units and on extent of the ice sheet of the Saalian Glaciation. Determination of regional stratotype horizons, establishing new key sites and sections of regional significance for Central Europe were based mostly on vegetation and paleoclimate changes recorded in glacial and interglacial lake deposits. Results of stratigraphical investigations abolished a predominant palaeogeographic image on ice sheet limits in this area. The Saalian maximum ice sheet limit was similar or even less extensive than during the subordinate Warta Stadial. Most of the area between the Middle Vistula in Poland and the Middle Dnieper in Belarus and the Ukraine was ice-free during this glaciation. On the other hand, immense glacial lobes during Saalian in the Middle Vistula and the Middle Dnieper valleys have not advanced presumably in the same time and were fed by ice moving from different parts of Scandinavia. Diversified Pleistocene tectonic uplifting in the area influenced much dynamics of the penultimate ice sheet in this part of Europe. [ABSTRACT FROM AUTHOR]

Pollen analysis was performed on a Lower Pleistocene lacustrine sedimentary sequence outcropping in Sousaki Basin, eastern Gulf of Corinth, Greece for the first time. The palynological assemblages revealed a stable climate, with regard to the glacial/interglacial climate variability timescale, with minor fluctuations in humidity, expressed as a relatively wet phase between 13.1 and 19.3 m and some transient increased aridity and humidity events. A Mediterranean type of vegetation presenting altitudinal zonation was evidenced for the first time in this region. Pinus and Quercus dominate, accompanied by other arboreal and non arboreal plants. The presence of rare taxa such as Taxodiaceae, Engelhardia , Liquidambar , Tsuga and Cedrus in very low percentages shows that these taxa remained in the area as relicts sometime between 2.8 and 1.5Ma. Palaeovegetation patterns from the Balkan Peninsula are lacking, especially during the Early Pleistocene. Thus, in this study a palaeoclimate reconstruction of the Early Pleistocene Sousaki Basin based on palynological data, is presented accentuating the effect of global climate changes in an area where no other similar records exist. [ABSTRACT FROM AUTHOR]