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This paper describes an approach assuming that already in the sea, based on the express analysis of visually similar cores of Arctic Holocene sediments and their comparison with dated and studied in detail cores of the regional sediments, it is possible to select a material that is promising for sequence stratigraphic correlation and paleoreconstructions. The range of lithological, colorimetric (CIE L*, CIE a*, and CIE b*), geophysical (magnetic susceptibility), and geochemical (Fe/Rb, Mn/Rb, and Ti/Rb) parameters is analyzed. The most informative characteristics include the CIE b* color coordinate, magnetic susceptibility, and Fe/Rb. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study on peat deposits and radiocarbon dating of basal peat horizons in 43 peatlands located on three key sites within Meshchera Lowlands and Moksha Polesie. Peatlands formed by upland paludification processes and located on watersheds and terraces rising above floodplains were selected for the analysis. The obtained data indicate that the peatland formation process has been ongoing in these regions throughout the entire Holocene epoch and that this process has been affected by the fire regime in the area. In periods with higher wildfire frequencies (8800–5800 and 4200–3200 calendar years BP), changes in the water balance on flat and poorly drained plains occurring after the destruction of forest stands intensified the waterlogging processes. [ABSTRACT FROM AUTHOR]

Marine oxygen isotope stage 5a (MIS 5a), MIS 3a, and Holocene were highlighted periods in paleoclimate studies. Many scientists have published a great number of studies in this regard, but they paid more attention to qualitative research, and there was often a lack of quantitative data. In this paper, based on chronological evidence from a paleolake in arid China, MIS 5a, MIS 3a, and Holocene lake area, the precipitation of the drainage area and the runoff of the inflowing rivers of the lake were reconstructed with ArcGIS spatial analysis software and the improved water and energy balance model which was calibrated by modern meteorological and hydrological data in the Shiyang River drainage basin. The results showed that the paleolake areas were 1824, 1124, and 628 km for MIS 5a, MIS 3a, and Holocene; meanwhile, the paleoprecipitation and runoff were 293.992-297.433, 271.105-274.294, and 249.431-252.373 mm and 29.103 × 10-29.496 × 10, 18.810 × 10-18.959 × 10, and 10.637 × 10-10.777 × 10 mm, respectively. The quantitative data can help us not only strengthen the understanding of paleoclimatic characteristics but also recognize the complexity and diversity of the climate system. [ABSTRACT FROM AUTHOR]

Loess, loess-like, sandy loess, and sandy-silty fluvial–aeolian deposits are intercalated to fluvial sediments and lie on a flat surface under intense agricultural land use in Bardibas, Mahottari district, central Nepal. To identify the depositional processes and provenance, we carried out geochemical, mineralogical, SEM, and grain-size analyses. Optically stimulated luminescence (OSL) dating shows the aeolian deposits are from the late Holocene (1.0–4.8 ka). Our results demonstrate that the loess and loess-like deposits (i) were dominantly sourced locally from deflation Quaternary sediments of the Terai Plain; (ii) are related to the composition of Siwalik rocks; and (iii) were deposited during dry periods of weak activity of the Indian Summer Monsoon. [ABSTRACT FROM AUTHOR]

High-resolution dating of volcanic rocks is the foundation for understanding the evolution of volcanoes and for estimating possible hazards. However, dating is often difficult for submarine volcanoes, where radiocarbon or other dating is frequently unavailable or imprecise. Here, we report paleointensity results from submarine basalts around Izu-Oshima Island, a typical island-arc volcano, and their bearing on age constraints. Basaltic lava samples were collected from submarine ridges located southeast of Izu-Oshima Island. Rock magnetic data indicate that the samples contain Ti-rich titanomagnetite with blocking temperatures of around 250–400 °C. The magnetic properties of the samples do not change significantly when heated in Ar or vacuum. We apply the Tsunakawa-Shaw method to estimate absolute paleointensity. Samples from different submarine ridges show distinct behavior. One ridge (SE1) shows moderate paleointensity of about 37 μT, while another ridge (SE3) records relatively strong magnetic fields of about 60 μT. Comparing those results with regional paleointensity data, we estimate the age of the SE1 ridge to be younger than 0.5 ka or around 1.4 ka. The other ridge (SE2) exhibits different paleointensity for two samples obtained from different localities, implying that the ridge consists of multiple eruptions. These results demonstrate that paleomagnetism can improve the dating of submarine volcanic rocks. [ABSTRACT FROM AUTHOR]

Copyright of African Archaeological Review is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the past decade research into the German Final Paleolithic and Mesolithic has experienced an important revival. One clear sign of this renewed interest in the periods are the annual meetings of the “Arbeitsgruppe Mesolithikum” (Mesolithic Working Group) which have taken place every spring since 1992. At these meetings, which take place at changing venues, topical themes of Final Paleolithic and Mesolithic interest are presented by informal lectures and it is also possible to study regional collections (artifacts, raw materials) at first hand. Numerous contributions were subsequently published together in one volume (Conard and Kind (1998) Aktuelle Forschungen zum Mesolithikum/Current Mesolithic Research, Mo Vince, Tübingen). The present paper intends to complement that collection of papers with a synthesis of developments and perspectives and to present recent research highlights in the German Final Paleolithic and Mesolithic, together with a comprehensive bibliography, to a wider international audience. [ABSTRACT FROM AUTHOR]

This paper considers regularities governing the formation of automorphic tundra soils on glacial loamy deposits containing relict organic matter mainly represented by very fine plant detritus. Drainage, microtopography, and cryoturbation activity are the major controls of the development of these soils. With an increase in drainage, the following pedogenetic trend is observed on the surface of yedoma (Ice Сomplex) areas: gleyzem-cryozem-cryometamorphic soil. The climate change in the Holocene induced quick transformation of topography and general landscape situation and promoted formation and development of cryogenic soil complexes in the considered territory. Upon the low intensity of pedogenesis, the features and properties of previous soil formation stages are often preserved in the soil profiles; these are: gleyzation, peat accumulation, and cryoturbation. [ABSTRACT FROM AUTHOR]

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Archaeological Review is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Estanilles peat bog, located in the northeastern Iberian peninsula, was studied to determine the anthropogenic changes in the landscape over the past seven millennia. The pollen diagram and sedimentary charcoal analyses from this site permit us to reconstruct the landscape changes in an area of both Mediterranean and Atlantic influence. In addition, Montarenyo ombrotrophic peat bog was studied to strengthen the analysis of data from more recent centuries. This paper attempts a reconstruction of historical cultural landscapes using two complementary palaeobotanical proxies (pollen and charcoal) in high mountain environments. The macroscopic charcoal record shows a fire signal since 7500 cal. b. p. However, the relationship between fire frequency and human impact is not always linear. This divergence is linked to fuel availability and fire activity. Fire has been used repeatedly to clear ground and to maintain open areas, and has been a key tool for the management of these high mountain areas. The intensity of use of the landscape implies the expansion of agricultural areas into higher altitudes, including cereal cultivation above 2,200 m a.s.l., during the Middle Ages. The first clear human influence detected in the pollen percentage data is recorded between 6000 and 7000 cal. b. p. and, until present times, the greatest changes in vegetation and landscape history occurred during periods of particular specialization in socioeconomic activities during the Middle Ages. [ABSTRACT FROM AUTHOR]

The Shiyang River drainage basin is located in the northwest margin of the Asian monsoon region. Previous studies reached different conclusions about Holocene climatic changes in the basin. Some studies suggested the Holocene climatic changes were mainly controlled by the Asian monsoon and that the climate was relatively humid during the early Holocene (11.6--7.1 cal ka BP). Other studies found the mid-Holocene Climatic Optimum (7.0--5.0 cal ka BP), and this climate condition was similar to the Holocene westerly wind pattern in arid Central Asia. The modern climate is affected by the Asian monsoon and westerly wind in the drainage basin, and the Holocene climatic records showed two different Holocene climatic patterns--a westerly wind pattern and monsoonal pattern. However, it remains unclear what caused the two different Holocene climatic patterns to co-exist in the region. The palynological records are the main evidence for the Holocene climatic changes in the basin. This paper focuses on palynological records for different parts of the drainage basin. Among them, QTH02, QTL-03 and Sanjiaocheng records are located in the terminal lake, and the Hongshuihe record is located in the middle reaches of the basin. In the terminal lake, the palynological records of QTH02 and QTL-03 are similar, but the Sanjiaocheng record differs. The difference is mainly affected by the variable pollen assemblages in the different locations of the lake basin. From comparison and synthesis of the four palynological records, we concluded that the millennial-scale Holocene climatic changes were affected by the combined effects of the Asian monsoon and westerly wind in the drainage basin, which show the complicated Holocene climatic pattern in the northwest margin of the Asian monsoon. [ABSTRACT FROM AUTHOR]

Balsam fir (Abies balsamea) and black spruce (Picea mariana) forests are the main conifer forest types in the North American boreal zone. The coexistence of the two species as well as their respective canopy dominance in distinct stands raises questions about the long-term evolution from one forest type to the other in relation to environmental factors including climate and stand disturbance. We tested the hypothesis that repetitive fire events promote the succession of balsam fir forest to black spruce forest and vice versa. Postfire chronosequences of one black spruce (BSP) and one balsam fir (BFI) sites were reconstructed based on the botanical composition and 14C-dated soil macrocharcoals. The results support the hypothesis of a successional dynamics. The BSP site has been affected by fires for the last 7600 years, whereas the BFI site, after having been impacted by several fires during the first half of the Holocene, evolved in a fire-free environment for the last 4400 years. Periods of fire activity facilitated the dominance of black spruce forests. The cessation of fires around 4400 cal. years BP on BFI site marks the beginning of the transition from black spruce to balsam fir stands. This succession is a long process, due to the ability of black spruce to regenerate by layering in the absence of fire. The resulting balsam fir stands are ancient and precarious ecosystems, since fire generally leads to the return of black spruce. The increase in balsam fir to the detriment of black spruce in boreal forests is a response to a decrease in fire frequency. [ABSTRACT FROM AUTHOR]

The recognition of Mesolithic impacts in mid Holocene pollen diagrams of the British Isles has led to the development of models describing sophisticated woodland management, particularly through the use of fire, by Mesolithic populations. However, the significance of human agency in creating mid Holocene woodland disturbances is unclear, with natural and human-induced clearings arguably indistinguishable in the pollen record. Analysis of non-pollen palynomorphs (NPPs) should aid the identification of events and processes occurring within these woodland disturbances and provide more precise palaeoecological data. In this paper we present pollen, charcoal and NPP analyses from a potentially critical location in the Mesolithic impacts debate. NPP types aid significantly in the reconstructions, suggesting periods of dead wood, grazing, local burning and wetter ground conditions. The results indicate that between 7700 and 6800 cal b.p., a predominantly wooded environment periodically gave way to phases of more open woodland, with inconsistent evidence for animal grazing. From 6800 cal b.p., a phase of open woodland associated with high charcoal concentrations and indicators of grazing was observed. This probably represents the deliberate firing of vegetation to improve grazing and browse resources, although it remains unclear whether fire was responsible for initially creating the woodland opening, or if it was part of an opportunistic use of naturally occurring woodland clearings. [ABSTRACT FROM AUTHOR]

Pinus tabulaeformis is an endemic species in northern China. The northern edge of its distribution corresponds to the northern margin of the monsoon climate. Several stands of Pinus tabulaeformis beyond its major range of distribution were found on the southeastern edge of the Inner Mongolia Plateau. Phytosociological analysis shows that the community structure, species composition and regeneration ability of Pinus trees in these stands are quite different from those within its continuous range of distribution. This paper presents palynological evidence to explain how and when these remnant communities were formed. Pinus tabulaeformis entered the study area in the mid-Holocene as the summer monsoon intensified, and declined when the summer monsoon weakened. Climatic change was the driving factor for the migration of Pinus tabulaeformis. It might be supposed that the competition between pine and oak forest during the mid-Holocene warm period also affected the immigration of pine. The remnant stands of Pinus tabulaeformis were apparently favored by the microhabitat of the sandy soils in valleys when the climate became drier. The remnant stands of Pinus tabulaeformis help stabilize the stand dunes. The protection of these stands is an important task of natural conservation in the study area. [ABSTRACT FROM AUTHOR]

Copyright of African Archaeological Review is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The deposition rate of the floodplain alluvium in various periods of the Holocene is determined for the Istra, Oka, and Seim rivers using a combination of dating methods (radiocarbon, radiocesium, and historical–archeological) and our original method based on estimation of the degree of evolution of the profile of soils buried in the alluvium. The spatial–temporal differences in the floodplain sedimentation rates are established as a result of chronological and soil-geomorphological studies. In the young floodplain areas, the rate is 1.8‒23 (Seim River) and 2‒15 (Istra River) mm/year in contrast to 0.01–0.70 mm/year in ancient areas (Oka and Seim rivers) in various deposition periods and when periods of intensified sedimentation were short. New refined data on typical sedimentation rates in floodplains of the center of the East European Plain are based on the study of the young fast-growing floodplain of the Istra River, the sediments of which are dated on the basis of historical–archeological materials: the sedimentation rate of the alluvium with and without pedogenetic features is 2‒15 and >15 mm/year, respectively, and the cumulative soils accumulate at a rate of 0.5–2 mm/year. Based on the 14С and archeological dates, the cyclic oscillations of the sedimentation rate in the Holocene are established along the Nikitino section (Oka River), which is characterized by a large series of well-developed paleosols: ~2 mm/year during the accumulation of the alluvium layers, which is 20 times higher than during the longer period of soil formation (0.07–0.14 mm/year). [ABSTRACT FROM AUTHOR]

Khorlakel Lake is located in the central sector of the Greater Caucasus, on its northern macroslope. The closed lake lies at an altitude of 2045.0 m above sea level on a tectonically determined subhorizontal step with a height of 2020–2100 m a.s.l. associated with the frontal part of the thrust. Two cores were drilled, and 17 samples for radiocarbon dating were taken in 2017 in the deepest (≈8 m) part of the lake, which made it possible to create an age model for the range from 8000 to 500 yr BP. To interpret the stratigraphic–temporal sequence of lacustrine sediments, integrated geological and geomorphological studies in the catchments of the lake and Elbashi Creek and in adjacent territories were conducted. It was established that sedimentation in the lake is associated with the influence of the adjacent Elbashi Creek. A number of episodes of proluvial activation over the last 8500 years with the formation of an proluvial fan have been traced. This was followed by lacustrine sedimentation in a dammed lake, the relic of which is Khorlakel Lake. As a result, sedimentation in Khorlakel Lake and in the adjacent territories is clearly divided into two stages with a partition at ≈3 ka BP with the sedimentation of mainly nonorganic material at the first stage and organic material at the second stage. These stages include ten episodes, which are characterized by different sediments features and varying proportions of mineral and organic components. It was found that the initial lake during the Holocene decreased in size due to the uneven growth of the proluvial fan formed by sediments delivered from the catchment of Elbashi Creek. It has been established that some lithostratigraphic boundaries in the bottom sediments of Khorlakel Lake correlate with known strong earthquakes in the Elbrus region, while other boundaries relate to climatic events in the Central Caucasus that occurred during the Holocene. The complete termination of the connection between the current Khorlakel Lake and the Elbashi Creek catchment occurred in the last ≈1 ka BP. [ABSTRACT FROM AUTHOR]

Geochemical study of volcaniclastic material and radiocarbon dating of charred plant debris from Holocene deposits of the Guram site, which is located in vicinity of Vetrovoi Isthmus on Iturup Island, demonstrate that an explosive eruption (VEI 4-5) occurred there about 2000 years ago. The geochemical and age similarity with the tephra of marker layer CKr that was distinguished on Iturup, Urup, Simushir, Rasshua, and Matua islands of the Kuril Island Arc led to the conclusion that this eruption is possibly a source of this tephra. The data presented are proposed as a motivation for revision of the volcanic hazard on Iturup Island. [ABSTRACT FROM AUTHOR]

Copyright of African Archaeological Review is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the results of pollen analyses from organic sediments of seven cores (299 spectra) in a mountainous area of the north-west Iberian peninsula. The pollen diagrams, supported by seven14C dates, are used to construct a regional pollen sequence covering the main stages of vegetation dynamics, from the last phases of the Late-glacial until the present. During the Late-glacial Interstadial an important development of cryophilous forests ( Betula and Pinus) was recorded, although various mesophilous and thermophilous tree elements were also present. The Younger Dryas, palynologically clearly defined, is characterized by an important reduction in tree pollen percentages and the expansion of steppe formations (Poaceae and Artemisia). At the beginning of the Holocene, there was an expansion of Quercus and a spread of other trees, which combined to give a vegetation cover of varied composition but dominated by mixed deciduous forests. Such forest formations prevailed in these mountains until 3000 years ago, when successive deforestation phases are recorded at various times as a result of increased farming activity. The results are compared with data from other mountainous areas in the northern Iberian peninsula and southern France. [ABSTRACT FROM AUTHOR]

The paleoclimatic reconstruction of the last 14 ka was carried out by GPR sounding, spore–pollen analysis, and radiocarbon dating of a peat section (7 m) located in the model bog of Valdai National Park (Novgorod oblast). The peat accumulation rates varied from 0.075 mm/yr during the Late Glacial to 0.15–1.15 mm/yr during the Boreal stage (when the level of the Valdai lakes dropped by 10 m) and up to 4.25 mm/yr in recent centuries. Numerous cycles of the Holocene warming/cooling events were within ±1–2°C compared to the current ones and were accompanied by moderate fluctuations in annual precipitation (±25–50 mm). The forest composition changes were the most considerable during the Atlantic period, when spruce–broad-leaved forests and oak woods were predominant. Over the last two thousand years, the regional vegetation dynamics has mainly been influenced by agricultural activity. [ABSTRACT FROM AUTHOR]

The results of interdisciplinary research conducted at the Late Neolithic settlements Algai and Oroshaemoe (Aleksandrovo-Gaisky district of Saratov oblast, Lower Volga region) dated back to the 7th–5th millennia BC are considered. Modern soils of the study area are represented by light chestnut soils (Eutric Cambisols (Loamic, Protocalcic, Ochric)). In archaeological excavations, anthropogenically transformed variants of the same soils have been identified. Reconstruction of paleoenvironmental conditions in the area of archaeological settlements and their comparison with data from other parts of the Lower Volga region attests to periodic aridization and humidization of the climate and the related alternation of the stages of soil formation and sedimentation. An analysis of two neighboring sites indicates that the rate of soil formation in the study area varied from 0.8 to 35 cm/100 years. The soil strata have been identified and subdivided into several series of Holocene soils of different ages. Sterile (light-colored horizons without artifacts) or B horizons serve as parent materials for each of the formed soils. Sterile horizons were formed under arid climatic conditions with the development of salt-affected soils. The duration of the formation of each Holocene soil varied. Cyclic stages of aridization and humidization of the climate have been observed during the entire Holocene against the general background trend of increasing humidization. [ABSTRACT FROM AUTHOR]

Spore–pollen analysis of lacustrine and subaerial sediments of the KamPlen reference section in the Central Kamchatka Depression (CKD) is conducted. The results of the analysis allowed the reconstruction of the CKD landscape formation conditions in the Late Peni-Glacial, Late Glacial, and the transition to the Holocene, which significantly expands the paleogeographical record elaborated for the Holocene of Kamchatka into the past. It is established that, after 18 ka (under relatively cold climate), the watershed of the paleolake that filled the CKD during the last glaciation was characterized by open landscapes with dominant herbaceous–grass communities. The presence of pollen of trees and warm water plants indicates the limited scales of mountainous–valley glaciation. The identified cooling period of 15–13 ka characterized by scarcer vegetation did not lead to a significant expansion of glaciers. After 13 ka, warming of the climate with a gradual degradation of glaciers resulted in regeneration of coniferous forests on the paleolake watershed. The drainage of the lake at ~11.5 ka BP and the beginning of sedimentation of subaerial deposits in the area of the studied section approximately correspond to the lower boundary of the Holocene, which confirms the key role of the climate at stages of the CKD landscape formation during the period considered. [ABSTRACT FROM AUTHOR]

Cosmogenic radionuclide records (e.g., 10Be and 14C) contain information on past geomagnetic dipole moment and solar activity changes. Disentangling these signals is challenging, but can be achieved by using independent reconstructions of the geomagnetic dipole moment. Consequently, solar activity reconstructions are directly influenced by the dipole moment uncertainties. Alternatively, the known differences in the rates of change of these two processes can be utilized to separate the signals in the radionuclide data. Previously, frequency filters have been used to separate the effects of the two processes based on the assumption that millennial-scale variations in the radionuclide records are dominated by geomagnetic dipole moment variations, while decadal-to-centennial variations can be attributed to solar activity variations. However, the influences of the two processes likely overlap on centennial timescales and possibly millennial timescales as well, making a simple frequency cut problematic. Here, we present a new Bayesian model that utilizes the knowledge of solar and geomagnetic field variability to reconstruct both solar activity and geomagnetic dipole moment from the radionuclide data at the same time. This method allows for the possibility that solar activity and geomagnetic dipole moment exhibit variations on overlapping timescales. The model was tested and evaluated using synthetic data with realistic noise and then used to reconstruct solar activity and the geomagnetic dipole moment from the 14C production record over the last two millennia. The results agree with reconstructions based on independent geomagnetic field models and with solar activity inferred from the Group Sunspot number. Our Bayesian model also has the potential to be developed further by including additional confounding factors, such as climate influences on the radionuclide records. [ABSTRACT FROM AUTHOR]

Stand-scale gap-phase dynamics is generally viewed as the main driver of development in mesic deciduous forests of the temperate biome. Soil charcoal of temperate forests in eastern North America are unnoticed in most surveys, thus explaining why fire is undervalued as a driver of forest succession. The extent to which gap-phase, fire, or other processes are responsible for the regeneration and maintenance of mesic deciduous forests is unknown because paleoecological evidence is lacking. We tested the fire-driven succession hypothesis on the development of this major forest type. Based on charcoal 14C dates of two sites, 44 and 55 fires occurred since early Holocene, with a mean interval of 170 to 215 years. The vegetation of both sites followed comparable post-glacial trajectories consisting of three distinct periods. Conifers dominated the two first periods during 5200–6000 years and were replaced by hardwoods–conifers over the last 3500 years. The first period was represented by boreal conifers, whereas the second period, dominated by white pine (Pinus strobus) forests, persisted during 3000–4300 years. The third period marked the development of hardwood (sugar maple, Acer saccharum) forests. Fires occurred continuously on the sites since early Holocene likely under dry conditions during the conifer periods and cooler and moister conditions during the hardwood–conifer period. Recurrent fires appear with climate as key drivers of the long-term dynamics of several temperate forests in eastern North America. Similar studies on other temperate forests should be pursued to test the hypothesis of climate–fire interactions influencing tree composition change. [ABSTRACT FROM AUTHOR]

Palaeoecological evidence indicates that highland pines were dominant in extensive areas of the mountains of Central and Northern Iberia during the first half of the Holocene. However, following several millennia of anthropogenic pressure, their natural ranges are now severely reduced. Although pines have been frequently viewed as first-stage successional species responding positively to human disturbance, some recent palaeobotanical work has proposed fire disturbance and human deforestation as the main drivers of this vegetation turnover. To assess the strength of the evidence for this hypothesis and to identify other possible explanations for this scenario, we review the available information on past vegetation change in the mountains of northern inland Iberia. We have chosen data from several sites that offer good chronological control, including palynological records with microscopic charcoal data and sites with plant macro- and megafossil occurrence. We conclude that although the available long-term data are still fragmentary and that new methods are needed for a better understanding of the ecological history of Iberia, fire events and human activities (probably modulated by climate) have triggered the pine demise at different locations and different temporal scales. In addition, all palaeoxylological, palynological and charcoal results obtained so far are fully compatible with a rapid human-induced ecological change that could have caused a range contraction of highland pines in western Iberia. [ABSTRACT FROM AUTHOR]

Fagus sylvatica (beech) dominates the montane forests of the Apennines and builds old-growth high-conservation value stands. However, recent severe drought-induced diebacks raise concern on the future persistence of these forests and of Southern European mesophilous woodlands overall, growing at their dry edge. To explore the history of Apennine beech-dominated forests, we draw on the multiproxy paleoecological record from Lago Verdarolo, which includes a robust vegetation-independent temperature reconstruction. Numerical techniques are used to investigate the drivers of long-term Mediterranean mountain forest dynamics. Specifically, we focus on disentangling the ecological factors that caused the shift from high-diversity mixed forests to beech-dominated stands and on assessing the occurrence of legacy effects on present-day forests. Abrupt climate change largely drove vegetation dynamics during the Late Glacial and Early Holocene. Species-rich mixed Abies alba (silver fir) forests dominated about 10,500—5500 years ago, under rather dry and warmer-than-today conditions (+ 1—2 °C) and limited fire occurrence. Cooler and moister summers and increasing fire activity caused declines in several fire-sensitive temperate deciduous trees (for example, Ulmus, Tilia, Fraxinus) and favored the establishment of fir-beech forests around 5500 years ago. Further enhancement of fire activity and farming around 2000 years ago led to local Abies alba extinction and forest impoverishment. We conclude that the currently widespread monospecific Apennine beech forests are the result of multi-millennial land-use intensification superimposed on Late Holocene cooling and moistening. Given their higher drought-tolerance compared to beech stands, reviving ancient species-rich mixed fir forests represents a feasible and 'tested' possibility to adapt forests to climate change. [ABSTRACT FROM AUTHOR]

The problems of diagnostics of the beginning of agrarian development of coniferous–broad-leaved forests in northwestern European Russia and its specificity regarding changes in the zonal forest cover and its anthropogenic modifications inherent in the forest and field-meadow landscape based on studying pollen spectra from key sections. It was established that the onset of the agrarian development of the forests in the region under consideration dates back to 2300–2600 cal years BP. Judging by the continuous presence of cultivated plant pollen in the diagrams, it becomes ubiquitous and irreversible after 1500 cal years BP. The corresponding indicators and plants are given. The presence of plant pollen grains in the diagrams makes it possible to establish the time and nature of agrogenic changes in the vegetation composition. [ABSTRACT FROM AUTHOR]

A new pollen record from Lago di Vico (core V1) provides fundamental new information towards reconstruction of flora and vegetation history in central Italy during the last 90 000 years. The chronological framework is secured by seventeen AMS14C dates, one40Ar/39Ar date and tephra analyses. At the base of the pollen record, i.e. shortly after the40Ar/39Ar date 87 000±7000 B.P., three phases with significant expansion of trees are recorded in close succession. These forest phases, which stratigraphically correspond to St Germain II (and Ognon?) and precede pleniglacial steppe vegetation, are designated by the local names Etruria I, Etruria II and Etruria III. During the pleniglacial, a number of fluctuations of angiosperm mesophilous trees suggest the presence of tree refugia in the area. The lowest pollen concentration values are recorded at ca. 22 000 B.P. which corresponds with other pollen records from the region. The late-glacial is characterized by an expansion in the arboreal pollen curves that is less pronounced, however, than in other pollen profiles from Italy. The Holocene part of the profile is consistently dominated by deciduous oak pollen. No major changes in arboreal pollen composition are recorded but several marked and sudden declines of the tree pollen concentration suggest that the forest cover underwent dramatic changes. Clear evidence for human impact is recorded only when cultivated crops became important which dates to ca. 2630±95 B.P. [ABSTRACT FROM AUTHOR]

Encouraged by new, ethnographically grounded interpretations of San rock art, Holocene hunter-gatherer research south of the Limpopo has undergone a partial paradigm shift over the last decade, away from ecological issues and in favor of questions of social organization and ideology. Earlier models relating changes in regional demography to environmental shifts now need revision, as do long-standing studies of seasonal mobility. New research emphasizes instead identification of exchange and alliance networks and patterns of seasonal aggregation and dispersal. However, several of the assumptions of these models remain untested, while dating problems make it difficult to integrate rock art with other components of the archaeological record. Critical use of a more diverse set of ethnographic data, from both within and beyond the Kalahari, is also needed. These points are emphasized in discussing evidence for social and economic intensification between 5000 and 2000 B.P. in several areas of the subcontinent (KwaZulu-Natal, the southern, eastern, and far western Cape). [ABSTRACT FROM AUTHOR]

The rapidly collapsing glacial systems of the Alps produced a large number of melt-water lakes and mires after the Last Glacial Maximum (LGM) in the Late Glacial period. The Rhone-Aare-glacier system gave rise to large moorlands and lakes in the region of the Three Lakes Region of Western Switzerland. When moorlands are formed, they are efficient sinks of atmospheric carbon, but when transformed to agricultural land they are significant C sources. In addition, mires can be used as archives for reconstructing landscape evolution. We explored in more detail the dynamics of the landscape of the Three Lakes Region with a particular focus on the formation and degradation of mires. The Bernese part of the Three Lakes Region developed to become—after the optimisation of the water-levels of the Swiss Jura—the vegetable belt of Switzerland. The situation for agriculture, however, has now become critical due to an overexploitation of the peatland. Until c. 13 ka BP the entire region was hydrologically connected. An additional lake existed at the western end of the plain receiving sediments from the Aare river. Around 13 ka BP, this lake was isolated from the Aare river and completely silted up until c. 10 ka BP when a mire started to form. In the valley floor (‘Grosses Moos’), the meandering Aare and the varying level of the nearby lake of Neuchâtel caused a spatio-temporally patchy formation of mires (start of formation: 10–3 ka BP). Strong morphodynamics having high erosion and sedimentation rates and a high variability of the chemical composition of the deposited material prevailed during the early Holocene until c. 7.5 ka BP. The situation remained relatively quiet between 5 and 2 ka BP. However, during the last 2000 years the hydrodynamic and geomorphic activities have increased again. The optimisation of the Swiss Jura water-levels during the nineteenth and twentieth centuries enabled the transformation of moorland into arable land. As a consequence, the moorland strongly degraded. Mean annual C-losses in agricultural land are c. 4.9 t ha−1 and c. 2.4 t ha−1 in forests. Because forests limit, but not stop, the degradation of mires, agroforestry might be tested and propagated in future as alternative land-use systems for such sensitive areas. [ABSTRACT FROM AUTHOR]

Recent and Late Pleistocene soils of the central forest-steppe in the East European Plain have been studied. The main objective of the work is to reveal changes in the properties of the Bryansk paleosol (final phase of MIS 3), one of the most important geosols of the Late Pleistocene. These changes could be induced by cryogenesis during the Valdai glaciation maximum (MIS 2) and by the Holocene pedogenesis (MIS 1) under different conditions of the modern microtopography. We have studied the catena of Holocene soils underlain by the Bryansk paleosol within a small closed depression in the Kazatskaya Steppe of the V.V. Alekhin Central Chernozemic Biospheric Reserve in Kursk oblast. The depression is supposedly the result of loess subsidence. Haplic Chernozems develop on the microelevation; Luvic Chernozems, on the microslope; and Luvic Chernozems (Stagnic), in the bottom of the depression. The upper humus horizons of the Holocene soils are similar in all parts of the microcatena. On the slopes and in the lower part of the microdepression, the Ah2 subhorizon is replaced by the AE horizon, and the Bk horizon becomes carbonate-free and turns into the Bt horizon. The change in the "normal" profile of the paleosol of the Bryansk Interstadial began already at the latest stages of its formation. The Bryansk soil was strongly deformed by cryogenic processes during the maximum of the Valdai glaciation (Vladimir cryogenic horizon). The secondary diagenesis of the Bryansk paleosol is associated with soil formation in the Holocene. Holocene soils are superimposed on the profile of the Bryansk paleosol, transforming it differently in various parts of the catena. On the microelevation, the diagenesis in the Holocene is regarded as minimal. The Bryansk paleosol is most transformed in the bottom of the microdepression. [ABSTRACT FROM AUTHOR]

Results of the study of humus composition in about 200 modern soils of different genesis and more than 100 buried Pleistocene and Holocene paleosols have been collected and analyzed. The content of the nonhydrolyzable part of soil organic matter (NH OM) in the paleosols is comparable with that in the modern soils (50 ± 15% and 54 ± 21%, respectively). Thus, NH OM does not accumulate in the buried soils during their diagenesis and is not the inert fraction of the soil organic matter (SOM). The NH OM content in the natural organomineral soil complexes–clay fractions of the soils—is lower than that in the whole soil mass. Data on the solid-state 13C NMR spectroscopy of the whole soil samples and the NH OM indicate that the latter are enriched in O-alkyls, including C of acetal groups. The whole soil mass is richer in C of aromatic structures and carboxyl groups. The degree of organic matter humification estimated from the alkyls/O-alkyls ratio for the NH OM is considerably lower than that for the whole SOM. The existence of negative correlation between the contents of NH OM and humic acids in the modern soils (R = –0.86) and in the buried paleosols (R = –0.83) has been shown. The NH OM content in the clay fraction in comparison with the whole soil mass is lower (36 ± 21% and 60 ± 15%, respectively). This reflects the accumulation of weakly decomposed plant residues in this part of the SOM. It is argued that the NH OM is heterogeneous and includes at least two groups of substances: clay-bound organic matter of organomineral complexes (nonhydrolyzable because of strong chemical bonds) and weakly decomposed plant residues resistant to acid and alkaline hydrolysis. The absence of definite relationships between the contents of NH OM and fulvic acids indicates that genetic links between the NH OM and humic acids are stronger than those between the NH OM and fulvic acids. 13C NMR spectroscopy of kerogen from the Carboniferous shale attests to the principal difference between the NH OM of soils and kerogen, in which C of alkyl groups predominates. [ABSTRACT FROM AUTHOR]

Fine-grained sediments in southern Finland were deposited during the retreat of the continental Fennoscandian ice-sheet at around 13,000 cal BP, leaving subsequent ice-contact deposits and postglacial lake and, finally, the modern brackish water Baltic Sea basin (BSB). As a result of the strong glacioisostatic land uplift of the region, these sediments today lie above sea-level in coastal Finland. The recent expansion of cities to locations where superficial sediments are more challenging for construction purposes has increased the need for comprehensive understanding of the properties and geometry of these fine-grained superficial deposits. Commonly used site-specific lithostratigraphical characteristics of clayey deposits run the risk of ambiguous correlation between sites because of different types of postglacial depositional settings. The present study applies an allostratigraphical approach to classify late- and postglacial clayey deposits using examples from four sedimentary basins in the vicinity of the city of Espoo along the southern coast of Finland. This entails a reinterpretation of 17 core logs collected during the period 2006-2009 and reported in earlier studies, combined with examination of five new cores collected in 2016 coupled with borehole measurements of resistivity-temperature and electrical resistivity tomography (ERT). Physical proxies and sediment characteristics demonstrate that grey postglacial lacustrine silty (Ancylus Lake) clay is truncated at the top by an undulating erosional surface (unconformity), which is covered by a silt to sand layer a few centimetres thick that has a gradual-bioturbated upper contact to the greenish-grey brackish water (Litorina Sea) mud. Sediments above and below the unconformity are intensely bioturbated, and black mottling of Fe-monosulphide is observed in the brackish water mud. Evidently, this unconformity is of high engineering-geological significance because the organic-rich brackish water mud has a poorer bearing capacity and higher abundance of sulphide minerals that form sulphuric acid upon oxidation. It is demonstrated that this unconformity is spatially well recognised and provides a key stratigraphic marker for wider and more accurate comparison between sites with fine-grained deposits in the Helsinki metropolitan area and potentially in other urban areas in the northern Baltic Sea region. [ABSTRACT FROM AUTHOR]

The rock shelter of Tan Zoumaitek, Tassili-n-Ajjer, Central Sahara, Algeria, famous for its paintings of humans and mammals, is found to contain as well several pictures of objects that are most likely medusae. Ii is argued that these can be identified as the afrotropical Limnocnida tanganjicae GUNTHER. The duration of their isolation, after the end of the early Holocene humid period, may be contemporaneous (c. 8000 years) with that of the extant relicts of that species in Mauretania and Chad. These figures are the oldest images of a cnidarian currently known. [ABSTRACT FROM AUTHOR]

Detailed study of a peat plateau near the southern boundary of the East European permafrost zone has been performed. The botanical and palynological compositions of the peat to the depth of 10 m, its radiocarbon dates (the AMS method), and its physical and chemical characteristics have been determined. The accumulation of peat in this area began about 8300 years ago at the end of the Boreal period. In the middle of the Atlantic period, the rate of peat accumulation reached 1.44 mm/yr. During the warming phase in the Middle Subboreal period, the peat plateau was subjected to active thermal erosion; part of the peat was eroded. The processes of thermal erosion are also active at present and destroy the edges of peat mounds. At the same time, the gradual accumulation of peat on the plateau continues. An increase in the degree of peat mineralization is expected upon the establishment of aerobic conditions against the background degradation of the permafrost. Peat plateaus and large peat mounds have been the sinks of atmospheric carbon for a larger part of their history. In this context, we do not expect their significant negative influence on the climate in the future. [ABSTRACT FROM AUTHOR]

The Late Holocene stage of forest pedogenesis has been studied on the interfluves along river valleys in the forest-steppe zone of the Central Russian Upland. The development of gray forest soils from the former chernozems as a result of the Late Holocene advance of forest vegetation over steppes is discussed. It is argued that the climatic conditions of the Subatlantic period were unstable, so that multiple alternation of forest and steppe vegetation communities took place. This specified a complex character of soil evolution upon contrasting substitution of forest pedogenesis for steppe pedogenesis. On the interfluves near the natural drainage network (balkas, ravines, and steep slopes of river valleys), the climate-driven dynamics of forest and steppe vegetation with corresponding changes in the character of pedogenesis could take place during the entire Holocene, which is reflected in a lower thickness of humus profiles and deeper leaching of carbonates from chernozems of the Early Iron Age in comparison with their analogues formed under steppe cenoses in central parts of the interfluves. Two variants of the evolution of gray forest soils can be suggested: the pulsating evolution typical of balkas and interfluves near river valleys and the continuous progressive evolution typical of automorphic (plakor) positions in central parts of the interfluves. [ABSTRACT FROM AUTHOR]

Shifts in an ecosystem's state can alter biogeochemical cycling and the extent of nutrient conservation within a terrestrial landscape on multiple time scales. Transient biogeochemical changes may follow disturbance and succession, although persistent long-term differences may exist under different climates and vegetation types. We evaluate the potential for such biogeochemical changes in the context of long-term ecological history by measuring the nitrogen isotope composition of organic matter in a lake sediment core. We targeted Little Windy Hill Pond (LWH) in the Medicine Bow Mountains, Wyoming because reconstructions of the lake level, fire, and vegetation histories from the lacustrine sediments indicated a century-scale transformation from an arid, shrub-dominated landscape to a sub-alpine, tree-dominated ecosystem with extensive woody cover and large, live biomass pools. We demonstrate that the afforestation at the beginning of the Holocene transformed the Artemisia-dominated ecosystem, which had persisted for millennia during the Pleistocene. The changes affected nitrogen cycling dynamics, especially through intensified nutrient conservation when live biomass pools increased with greater woody cover. The LWH sediments record a baseline δN shift from 2.2-3.0 to 0.3-2.0‰ as less N-enriched organic matter accumulated in the lake. We also observed a transient pattern of maximum nutrient conservation and minimum δN values as terrestrial biomass increased during the aggradation (~175 years) and transition phases of ecological succession. Our nitrogen isotope results support theoretical expectations of long-term biogeochemical dynamics as nutrient conservation increases during afforestation. [ABSTRACT FROM AUTHOR]

A chronosequence of soils in the area of the Palasa-Syrt burial mounds in the Republic of Dagestan is examined. It includes one paleosol under a kurgan of the Middle Bronze Age (end of the third-beginning of the second millennium BC), twelve paleosols buried at the end of the Late Sarmatian period-the beginning of the Great Migration period (second half of the fourth-first half of the fifth centuries AD), and two background soils. As shown by our study, desertification processes during the Middle Bronze period resulted in the replacement of the light chestnut soil by the brown semidesert soil. In the second studied chronointerval, the soils developed in the semidesert zone; however, the first half of this chronointerval was relatively humid, whereas the second half (in the fifth century AD) was more arid, which was reflected in the soil properties. The grouping of the Late Sarmatian paleosols with respect to their properties made it possible to arrange their chronosequence and, thus, to judge the time of their burial, which was confirmed by the archaeological data. The sequence of changes in the soil properties upon changes in the climatic conditions is identified. The first features that disappear upon humidization and reappear upon aridization of the climate are the features of salinization and solonetzic processes and the character of the biological activity. The C age of carbonates also changes. These relatively quick processes are realized in 10-20 years, whereas the changes in the reserves of humus and carbonates require longer periods (supposedly, about 50-100 years). [ABSTRACT FROM AUTHOR]

Holocene mangrove dynamics are reconstructed from pollen, sediment and radiocarbon analyses of three cores (ANR, BNR, CNR) located across a 20 km transect in the Rufiji Delta, Tanzania. At the base of the sediment sequence, dated to about 5600 cal. year b. p., the mangroves which are present suggest a low intertidal ecosystem in response to wet conditions and a higher sea level than at the present day. After around 5600 cal. year b. p. in core BNR, mangroves retreated seaward probably due to a lower sea level and drier environmental conditions. At around 4640 cal. year b. p., mangroves shifted landward suggesting a phase of sea level rise. In the late Holocene, mangroves became established at higher elevations of the Rufiji Delta, which is now a paddy field. Mangrove taxa decreased after 1170 cal. year b. p., suggesting drier conditions and less inundation frequency, possibly due to a lower sea level. Marked vegetation changes from mangroves to terrestrial vegetation occurred after around 750 cal. year b. p., possibly related to sea level regression and/or a desiccation phase recorded during the late Holocene. Paddy fields replaced mangroves in the landward part of the transect, reflecting an increase in human settlement in this area, a trend that continues to the present day. The recent decrease of mangrove species, particularly Rhizophora mucronata, could suggest less inundation by saline water and a lower sea level, although these changes may also be due to human activities during the last millennia as indicated by charcoal analysis. [ABSTRACT FROM AUTHOR]

The radiocarbon-dated palaeoecological study of Lago Riane (Ligurian Apennines, NW Italy) presented here forms part of a wider investigation into the relationships between Holocene vegetation succession, climate change and human activities in the northern Apennines. The record of vegetation history from Lago Riane indicates that, since the end of the last glaciation, climate change and prehistoric human activities, combined with several local factors, have strongly influenced the pattern and timing of natural vegetation succession. The pollen record indicates an important change in vegetation cover at Lago Riane at ~8500-8200 cal. years b.p., coincident with a well-known period of rapid climate change. At ~6100 cal. years b.p., Fagus woodland colonised Lago Riane during a period of climate change and expansion of Late Neolithic human activities in the upland zone of Liguria. A marked decline in Abies woodland, and the expansion of Fagus woodland, at ~4700 cal. years b.p., coincided with further archaeological evidence for pastoralism in the mountains of Liguria during the Copper Age. At ~3900-3600 cal. years b.p. (Early to Middle Bronze Age transition), a temporary expansion of woodland at Lago Riane has been provisionally attributed to a decline in human pressure on the environment during a period of short-term climate change. [ABSTRACT FROM AUTHOR]

The mid-continent of North America has experienced dramatic and abrupt climate change during the Holocene, but the response of grassland vegetation to past climate change has been difficult to quantify. To improve interpretation of tallgrass prairie vegetation from pollen assemblages, we acquired and analysed a surface sample set collected from 25 small ponds (less than 10 ha surface area) in the largest contiguous remnant of tallgrass prairie in the USA. We compared these tallgrass prairie assemblages to 476 modern pollen samples classified as 'prairie' in the North American Surface Sample database. We then compared the surface pollen assemblages with fossil pollen assemblages from sediment cores at two sites in Kansas-Cheyenne Bottoms and Muscotah Marsh-using the modern analog technique. Pollen assemblages in the Flint Hills surface samples were very similar to each other, with an average squared chord distance of 0.19. They were different than other modern grassland pollen assemblages mainly due to higher percentages of pollen from six woody taxa: Carya, Cornus, Juniperus, Juglans, Maclura, and Platanus. Arboreal pollen percentages ranged from 17 to 62 % and did not correlate with woody cover among sites. Cheyenne Bottoms was open grassland for the past 25,000 years, but it did not have many tallgrass prairie analogs. Muscotah Marsh did not have many grassland analogs over the past 30,000 years, possibly due to its position on the prairie-forest border or its surrounding wetland vegetation. [ABSTRACT FROM AUTHOR]

The lake sediment record was used to reconstruct past vegetation dynamics and human impacts from the middle Neolithic (6500 cal. b.p.) to the Middle Ages (1500 cal. b.p.) around Lac d'Antre in the southern Jura mountains of France. This lake was surrounded by the Gallo-Roman sanctuary of Villards d'Héria, which has been widely investigated by archaeologists and enables a comparison between palaeoenvironmental proxies and archaeological data. Pollen and microscopic charcoal analyses were conducted on a 500 cm sediment core with eleven radiocarbon dates providing the chronological control. In a mixed oak woodland context, the successive development of Taxus, Fagus and Abies were mainly caused by climatic variations during the Neolithic, in which there was weak human impact. The first significant signs of human activity were detected during the Bronze Age from 3900 cal. b.p., followed by an increase of human pressure and woodland clearances during the Iron Age, from 2700 cal. b.p. The occupation of the Gallo-Roman sanctuary was continuous with the Iron Age occupation. All the analysed palaeoenvironmental data indicate that the strongest human impact occurred during the Gallo-Roman period, which matches the occupation of Villards d'Héria previously dated by archaeologists from 2000 to 1700 cal. b.p., 1st to 3rd century a.d. Moreover, there appears to have been a new period of human settlement close to the lake at the beginning of the Middle Ages. The low charcoal accumulation rate (CHAR) recorded during the Bronze and Iron Ages suggests that fire was not the main agent used to clear the dense woods to create new cultivated fields and pastures. High CHAR values recorded during the Roman period may represent fire use for domestic and agro-pastoral activities. [ABSTRACT FROM AUTHOR]

A detailed, AMS C-dated, pollen record from Cooney Lough, a small lake in Co. Sligo, western Ireland, is presented. Fluctuations in the pollen curves, indicative of changes in pollen productivity and shifts in woodland composition, suggest that the period spanned by the record (9.4-6 ka) was characterised by considerable climate instability. In all, five climate anomalies are recognised (CA-1 to CA-5). The most pronounced anomaly, CA-3, is dated to 8.45-8.2 ka, with the high point of that anomaly (CA-3b) centred on 8.2 ka and lasting about a century. On the basis of age, and also intensity and structure, CA-3b is equated with the 8.2 ka event as recorded in many proxies and especially the Greenland ice-core δO records. Key features of the event as recorded in the lake sediments include increased representation of Betula and Pinus (birch and pine; both widely recognised as cold tolerant trees) and a decline in Corylus and also Quercus (hazel and oak; both thermophilous). The anomalies CA-1 and CA-2 precede the 8.2 ka event, the former corresponding probably to the 9.2 ka event and the latter more pronounced, centred on ca. 8.8 ka and with a duration of approximately 100 years. The CA-4 event, at ca. 7.5 ka, is relatively minor as regards intensity while CA-5, which began at ca. 7.1 ka, initiated what seems to be a more long-lasting shift towards cooler conditions. The relationship of these developments to the arrival and expansion of alder ( Alnus), a key feature of the Boreal/Atlantic transition in European, including Irish pollen records is also discussed. [ABSTRACT FROM AUTHOR]

Pollen assemblages recovered from a 5 m sediment core from the Vravron coastal marsh suggest a close correlation between vegetation development and human presence in Attica, and provide the first complete record of middle to late Holocene vegetation history. Correlation of pollen with archaeological data attempts to decode the man-environment relations of the past, within the context of the known climatic variability of the mid-late Holocene, in the vicinity of ancient Athens, an area of high historical significance. The pollen record of Vravron denotes a rather variable landscape where open Mediterranean evergreen pine woods alternated with maquis shrublands and grasslands, where human activities and climate have left their imprints on vegetation. During the last 5,000 years agricultural practices displayed several variations: cereal cultivation appears more intense during the Bronze Age, especially in the Mycenaean, while a spread of Olea is observed during Geometric to Classical times. The gradual abandonment of Olea cultivation evidenced in our pollen diagram came as a result of the displacement of human activities in the interior of Mesogaia in Hellenistic and Roman times. Olea and cereal cultivation intensification is observed again during the Mesobyzantine period. In the upper part of the core evidence of intense soil erosion and expansion of Vravron wetland was recorded, coinciding with the Little Ice Age climatic event and the introduction of Arvanites populations in the area. [ABSTRACT FROM AUTHOR]

Past vegetation change and the influence of climate change and anthropogenic pressure during the Holocene is constructed from a series of palynological records sampled from three locations within the territory of the antique site of Sagalassos. The disappearance of the original deciduous oak woodlands and increases in anthropogenic indicator species around 5300 and 4300 b.c. correspond with an increase in settlements in the region. A period of drought following the deforestation may have hampered the recovery of deciduous oak. The timing of the onset of the Beyşehir Occupation Phase (BO-Phase) in the territory differs between locations, estimates ranging from ca. 1000-800 b.c. to the start of the Hellenistic period (334 b.c.). The most intense period of arboriculture coincides with the Roman and late-Roman periods. Increases in human pressure on the landscape as reflected in the pollen record correspond with an increased rate of sedimentation and fire activity. The timing of the end of the BO-Phase again differs between locations. Estimates range from the 4th century a.d. to the mid 7th century a.d., when a region-wide shift to dry environmental conditions is observed. Numerical analyses show that post BO-Phase vegetation change is largely driven by climate and displays a succession of dry and wet periods that coincided with well-defined European climate shifts, including the Medieval Climate Anomaly and the Little Ice Age. Current agricultural activities in the region are of a very recent (20th century) origin. [ABSTRACT FROM AUTHOR]

A Holocene palaeorecord from Lake Shudu, Yunnan Province, southwestern China is dominated by (1) a pronounced basin-wide sedimentary hiatus after ca. 7.2 kcal yr BP, spanning some 4,000 years and (2) significant changes in sediment source/supply and an increase in heavy metal influx coupled with a shift to more eutrophic lake conditions from ca. 0.9 kcal yr BP, lasting ~300 years. The hiatus is most likely a due to a significant and abrupt reduction in sedimentation rates, the driver of which is unclear; although it appears likely to have been climatically driven. The environmental changes captured in the Lake Shudu palaeorecord provide unambiguous evidence of late Holocene anthropogenic activity, most likely linked to mining activity. [ABSTRACT FROM AUTHOR]

The practice of medicine is a fruitful marriage of classic diagnostic and healing arts with modern advancements in many relevant sciences. The scientific aspects of medicine are rooted in understanding the biology of our species and those of other organisms that interact with us in health and disease. Thus, it is reasonable to paraphrase Dobzhansky, stating that, 'nothing in the biological aspects of medicine makes sense except in the light of evolution.' However, the art and science of medicine are also rooted in the unusual cognitive abilities of humans and the cultural evolutionary processes arising. This explains the rather bold and inclusive title of this essay. The near complete absence of evolution in medical school curricula is a historical anomaly that needs correction. Otherwise, we will continue to train generations of physicians who lack understanding of some fundamental principles that should guide both medical practice and research. I here recount my attempts to correct this deficiency at my own medical school and the lessons learned. I also attempt to summarize what I teach in the limited amount of time allowed for the purpose. Particular attention is given to the value of comparing human physiology and disease with those of other closely related species. There is a long way to go before the teaching of evolution can be placed in its rightful context within the medical curriculum. However, the trend is in the right direction. Let us aim for a day when an essay like this will no longer be relevant. [ABSTRACT FROM AUTHOR]

We reconstructed the palaeoenvironmental conditions of the last ca. 8,000 years in the Tres Lagunas region of the Quimsacocha volcanic basin (ca. 3,800 m a.s.l.) in the southwestern Ecuadorian Andes. By means of a pollen and charcoal record, we analysed vegetation, fire, and climate history of this area, which is sensitive to climatic changes of both the Pacific as well as of the eastern Andes and Amazon region. Sediment deposits, pronounced increases of pollen and charcoal concentrations, and pollen taxa reflect warmer and drier conditions in the early to mid-Holocene (~8000 to 3900 cal. b.p.). During the late Holocene (2250 to −57 cal. b.p.), five warm and cold phases occurred at Quimsacocha. The most prominent cold phase possibly corresponds to the globally recognized Little Ice Age (LIA; ~600 to 100 cal. b.p.). The cold phase signal at Quimsacocha was characterized by a higher abundance of Poaceae, Isoëtes and Gentianella, which are favoured by cold and moist conditions. Frequent charcoal particles can be recorded since the early to mid-Holocene (~7600 b.p.). The high Andean tree species Polylepis underwent several phases of degradation and re-establishment in the basin, which could indicate the use of fire by pre-Columbian settlers to enhance the growth of preferred herb species. The Tres Lagunas record suggests that human populations have been influencing the environment around Quimsacocha since the last ca. 8,000 years. [ABSTRACT FROM AUTHOR]