- Email: [email protected]
Biostratigraphy of the Late Pleistocene (Late Neopleistocene) of the Southern Urals region: correlation with other regions
106
Abstracts / Quaternary International 279-280 (2012) 9–120
these three lakes is strongly influenced by climate variability and human disturbance. This is represented mainly by the predominance of organocarbonate fraction under the effect of advancing the trophic status of the lakes. The detrital alumino-silicate elements and ferromagnesian recorded in modern sediments appear synchronous with the strong hydrolysis of soil during wet periods. A dozen terraces located in the borders of the lakes were sampled and studied. Seven radiocarbon dates were obtained on organic matter and shells. The time period concerned is between 2300 yr B.P and 400 yr B.P. The results show a high lake level at about 2300 yr B.P. The Lake Iffer was deeper by about 30 m from its current level. 1000 yr B.P probably marks the beginning of the decline with a drop in lake level of 20 m, which is ongoing in connection with climatic conditions become drier. MOROCCAN CLIMATE VARIABILITY BETWEEN EIGHTEENTH AND NINETEENTH CENTURY USING DOCUMENTARY SOURCES Brahim Damnati. UAE. Faculty of Sciences and Techniques-Tangier, Morocco E-mail address: [email protected]
There is only very limited climate information available from northern African countries based on documentary evidence. In Morocco, recent studies of logbooks for the period between 1727 and 1900 show much very interesting information. This climatic information was obtained from a wide variety of documentary sources such as private correspondence, brief relations describing extreme events, and particularly agricultural records (famine, floods.). Results of these studies indicate rainfall fluctuations, without abrupt changes, in the following alternating dry and wet phases: 1721-1724 dry, 1728-1729 wet, 1737-1738 dry, 1742-1744 dry, 1750 dry, 1776 dry, 1777-1778 wet, 1779-1782 dry, 1782-1783 wet, 1801-1816 wet, 1816-1817-1818 dry, 1825-1826 dry. Between 1727 and 1826, there were over six periods of drought, with a minimum of 13 years and a maximum period of 38 years. From 1826 to 1900 more than 9 dry periods were observed. If we compare these results with the results obtained by tree ring (Till and Guiot, 1990), there's a very interesting concordance. Till and Guiot (1990) published a 900-year reconstruction of OctoberSeptember precipitation for three different areas in Morocco, indicating a continuous tendency towards a wetter climate during the twentieth century, and drier conditions than present during the sixteenth, seventeenth and eighteenth century. THE USE OF FIRE FOR ECOSYSTEM MANAGEMENT: TRACKING THE EMERGENCE OF H. SAPIENS BEHAVIOURAL MODERNITY IN SOUTHERN AFRICA Anne-Laure Daniau. CNRS UMR PACEA-EPOC, Université Bordeaux 1, France E-mail address: [email protected]
It has been proposed that a greater control and more extensive use of fire was one of the behavioural innovations that emerged in Africa among early H. sapiens, favouring their spread throughout the world and determining their eventual evolutionary success. We would expect, if extensive fire use for ecosystem management were a component of the modern human technical and cognitive package, as suggested for Australia, to find major disturbances in the natural biomass burning variability associated with the occupation of Africa by H. sapiens. One of the aims of the TRACSYMBOLS project is to examine how key behavioural innovations emerged among H. sapiens in southern Africa, explore whether environmental variability influenced this development between 180 and 25 ka (Marine Isotope Stages 6 to 3), and establish if some of these innovations had an impact on African environments. Swift changes in environment in Africa during this period may have accelerated individual and general purpose social learning mechanisms that currently characterize humans. We will present preliminary results of the analysis of microcharcoal preserved in a deepsea core located off the Orange river's mouth that provides a record of the fire regime variability of this large river catchment basin. The direct correlation between marine and terrestrial (vegetation) climate proxies provides a unique opportunity to tackle fire regime variability in response to climate change and human adaptation. This approach has already been applied to Western Europe, where the fire regime follows the DansgaardOeschger climatic variability and appeared not controlled or influenced by Neanderthals or Anatomically modern populations.
PREDICTABILITY OF BIOMASS BURNING IN RESPONSE TO CLIMATE CHANGES Anne-Laure Daniau. CNRS UMR PACEA-EPOC, Université Bordeaux 1, France E-mail address: [email protected]
We used a worldwide compilation of w700 charcoal records to relate biomass burning to climate changes over the past 22 kyr. Much of the recorded variability reflects a global shift from low glacial to higher interglacial burning. The increase of global biomass burning starts earlier in the southern hemisphere than in the northern hemisphere, consistent with asynchronous warming shown by polar ice cores. Northern hemisphere burning increased through the Holocene while southern hemisphere burning initially declined and subsequently increased. Biomass burning was low in the northern tropics and high in the southern tropics in the early Holocene. These zonal trends are reproduced using an empirical function linking charcoal and time-varying temperature and precipitation minus evaporation (P-E) simulated using orbital, ice-sheet and greenhouse-gas forcing. This function shows fire increases with increasing temperature but peaks at intermediate levels of P-E. The same relationships are found by using an analysis of the spatial variations of contemporary burnt area and climate. This predictable response of fire to climate has serious implications on a warming Earth. AEOLIAN RECORDS OF ABRUPT ENVIRONMENTAL CHANGES IN SOUTHERN SIBERIA DURING MIDDLE-LATE HOLOCENE BASED ON THE RESEARCH IN THE LAKE BAIKAL REGION Lidia Danko. V.B. Sochava Institute of Geography SB RAS, Russian Federation E-mail address: [email protected]
The areas under study are situated in the southern and northeastern part of the Lake Baikal Region (southern Siberia). In the intermountain depressions, so-called Barguzinskaya Valley and Tunkinskaya Valley, local dune fields and loess-like sediments have formed. The present climate within these areas is continental, characterized by low precipitation (mean annual amount of 250-300 mm) and wide annual range of temperature. Six periods with formation of the aeolian deposits: earlier 6000, later 5000, from 2900 to 2400 and 2000 to 1600, about 800 and 400-500 cal. years BP, are recognized. It shows a periodical formation of the aeolian sediments under the conditions of a significant lowering of humidity. The buried soils serve as a proof for most humid phases. Consequently, sedimentation conditions did not remain permanent, evidencing environmental instability. The frequency and range of these events requires additional study, although the available records make it clear that the abrupt environmental changes were forced by climatic aridity. The aeolian events reconstruction has also been compared to vegetation dynamics derived from Lake Baikal pollen records [Tarasov et al., 2007]. According to this work relatively high score of the steppe biome occurs around 7500, 5500, 3000 and 1000-500 cal. BP. The similarities between the results may indicate that humidity fluctuations are regional character. It also is supposed that local aeolian records indicating a mainly dry condition in the Baikal Region as well in southern Siberia. The abrupt environmental changes, however, were mostly expressed in the local semiarid landscapes. A comparison our results with the weak monsoon episodes [Wang et.al, 2005; Xingqi et al., 2009] and climate changes in the central Asia [Xiaoping et al., 2004; Yang, 2009] shows simultaneous these events. Thus, initiation of aeolian activity in the Lake Baikal Region during Middle-Late Holocene was associated with large-scale circulation processes. BIOSTRATIGRAPHY OF THE LATE PLEISTOCENE (LATE NEOPLEISTOCENE) OF THE SOUTHERN URALS REGION: CORRELATION WITH OTHER REGIONS Guzel Danukalova. Institute of Geology, Russian Federation E-mail address: [email protected]
Published and unpublished material dealing with the stratigraphy of the Late Pleistocene (Late Neopleistocene according to the Russian stratigraphic scheme) of the Southern Urals is summarized. The results of the mammalian, mollusc and palynological investigations have been used in
Abstracts / Quaternary International 279-280 (2012) 9–120
the reconstruction of the palaeoenvironments and provide the basis for the stratigraphical subdivision. The local stratigraphic subdivisions are named: Kushnarenkovo, Saigatka, Tabulda, Kudashevo. The stratigraphic positions of the main Upper Neopleistocene localities and their precise definitions are given. The beginning of the Late Neopleistocene coincided with a phase of incision of the river valley and, probably with a significant uplift. Fluvial sediments formed the second terraces above the floodplain, but were almost entirely destroyed by the subsequent erosion. The climate was warm and wet. The Saigatka time was cold. Small hanging glaciers developed in the mountains. Altitudes of the mountains were close to their present-day values. River erosion was slow. Floodplain sediments are preserved in small areas; they constitute the upper parts of the second terraces. In Tabulda time, the incision of the hydrographic network increased. This was related with the uplift of the Southern Urals. Subsequently, the incision was replaced by lateral erosion, which destroyed the second terrace. Fluvial sediments now form the lower parts of the first terraces. The climate was moderately warm at that time. The Tabulda Horizon corresponds to the interglacial. The situation changed in the Late Neopleistocene which became colder. The southern Cisuralia region suffered deep seasonal frost penetration. Loess-like sediments form the upper parts of the first terraces and cover the watersheds; they contain cryogenic structures. There are known several Paleolithic sites. Local units are correlated with the stratigraphic schemes of the East European Platform, Lower Volga, Middle Urals, and Western European stratigraphic successions. MALACOLOGICAL CHARACTERISTIC OF THE MIDDLE PLEISTOCENE LOESS (MIS-6) OF THE BATAJNICA LOCALITY (SERBIA) Guzel Danukalova. Institute of Geology, Russian Federation E-mail address: [email protected]
The Batajnica loess section is situated 15 km NW of Belgrade on the right bank of the Danube river. The main aim of investigations in 2010 was to get the mollusc species characteristics during the Middle-Upper Pleistocene transition. Analysed deposits correspond to the upper part of the soil (VS1¼MIS 5), loess (VL2¼MIS 6) and the soil (VS2¼MIS 7). Every 15 cm of deposits had been sampled and washed with sieves of 0.75 mm. A total of 4817 mollusc shells of 13 terrestrial species families and 1 freshwater species were determined. Mollusc complex of VL2 is the most diverse in species and quantitatively: Succinia cf. oblonga, Cochlicopa lubrica, Cochlicopa sp., Pupilla muscorum, P. Bigranata, Pupilla sp., Vertigo pygmaea, Truncatellina cylindrica, Chondrula tridens, Chondrula sp., Vallonia costata, V. pulchella, Vallonia sp., Helicella striata, Granaria frumentatum, Granaria sp., Helicopsis sp., ? Oxychilus sp., Limax cf. maximus, Clausilia cf. dubia, Clausilia sp., Punctum pygmaeum, and Anisus sp. The upper part of the lower soil (VS1) contains shells of Cochlicopa sp., Pupilla muscorum, Pupilla bigranata, Pupilla sp., Vertigo pygmaea , Truncatellina cylindrica, Chondrula tridens, Chondrula sp., Vallonia costata, Vallonia pulchella, Vallonia sp., Granaria frumentatum, Granaria sp., Helicopsis sp., Limax cf. maximus. Few shells of Pupilla muscorum, Vertigo cf. pygmaea, Truncatula sp., Chondrula sp., Vallonia costata, Vallonia sp., Helicella striata, and Limax cf. maximus were extracted from the upper soil (VS2). Loess (VL2) corresponds to the cold interval of the global climate changes. At the same time molluscs (VL2) indicate moderate climate and open landscapes with small broadleaved forests. Mollusc complexes of VL2, VS1 and VS2 show almost the same species composition which suggests refugium existence at the investigated area. Contrary mollusc complexes (MIS 6) from Urals and Russian Plain have less species variety and have small individual quantity in comparison with Batajnica section. HURRICANE ACTIVITY DURING THE LATE HOLOCENE IN NEW ENGLAND, USA, BASED ON OPTICAL DATING Femke Davids. Aberystwyth University, United Kingdom E-mail address: [email protected]
Major hurricanes can be a cause of much loss of life, property and infrastructure. In the densely populated coastal regions of southern New
107
England, therefore, it is of the utmost importance to produce reliable predictions of hurricane activity. Since the instrumental and historical records are very short, long term predictions, on the scale of decades and centennials, present a challenge. The geological archive presents an opportunity to investigate long term variability. The storm surges associated with hurricanes can deposit sand overwash layers in coastal back barrier marshes or lakes. Davids et al. (2010) showed that these overwash layers can be successfully dated with optical dating: both with quartz as well as K-feldspar optically stimulated luminescence (OSL). This paper will present the optical dating results for three field sites within ca. 50 km of each other on the southern New England coastline. A number of radiocarbon ages provide independent age control for the prehistoric hurricane events. The results demonstrate that both prehistoric and historic hurricane events can be well correlated in these field sites and show two periods of increased hurricane activity during the last 3000 years. A HIGH RESOLUTION RECORD OF MAJOR STORMS AND HURRICANES DURING THE LAST MILLENNIUM IN OYSTER POND, NEW ENGLAND (USA), BASED ON MULTIPLE PROXIES Femke Davids. Aberystwyth University, United Kingdom E-mail address: [email protected]
Back barrier coastal lakes can preserve overwash events associated with major storms and hurricanes as distinctive sandy layers between organic mud deposits. Oyster Pond, which is situated on the southern coastline of New England, has a high sedimentation rate and is sensitive to storm surge inundation and has therefore preserved many overwash events. This paper will present the high resolution results of a study investigating the major storms and hurricanes preserved as overwash layers during the last millennium, based on radiometric dating (optical, radiocarbon, cesium and lead), pollen concentrations and grain size analysis of two sediment cores. There is good agreement for the major hurricanes from the 19th and 20th Centuries between the cores and the historical record. However, the Great Colonial Hurricane (AD 1635), which has been interpreted as a major hurricane from historical records, is not clearly present in this record even though this site is very sensitive to washover. Furthermore, this hurricane has been found in many other sites along the southern New England coastline. This paper will address the possible reasons for this discrepancy between records. EXPLORING MODERN IMPACTS ON UPLAND LANDSCAPE PROCESSES USING MULTIPROXY PALAEOENVIRONMENTAL RECONSTRUCTION TECHNIQUES Heather Davies. University of Plymouth, United Kingdom E-mail address: [email protected]
The modern period (w AD 1750 onwards) is often considered to be sufficiently described by historical records, and has tended to be relatively neglected by palaeoenvironmental research, the main focus of which is often millennial-scale environmental changes. British uplands have become the focus of a variety of projects in recent years to preserve important vegetation communities, prevent carbon loss and downstream flooding, and improve water quality. However, as long-term data on vegetation change, and the impacts of human land use on water quality, are often unavailable, setting restoration targets or making predictions for future change is difficult. The aim of this project is to create high-resolution multiproxy palaeoenvironmental records for the last 200-300 years from an upland catchment (Venford Reservoir) on Dartmoor (southwest England, UK) using sediment records from reservoir and peat cores. Through pollen and charcoal analysis vegetation and fire histories have been reconstructed along with diatom-inferred total phosphorus and pH levels. The results of the pollen and diatom palaeoecological analyses will be compared to explore whether changes in human land use coincide with shifts in water quality. Measurements of radio-isotope activity (210Pb and 137Cs) from the reservoir cores have provided evidence of catchment erosion possibly related to peat cutting. Initial results indicate that the 210Pb signal has been diluted in the most recent reservoir sediment, which occurs simultaneously with increased 137Cs activity, indicating that new material is being in-washed from the catchment. The results of the project
Abstracts / Quaternary International 279-280 (2012) 9–120
these three lakes is strongly influenced by climate variability and human disturbance. This is represented mainly by the predominance of organocarbonate fraction under the effect of advancing the trophic status of the lakes. The detrital alumino-silicate elements and ferromagnesian recorded in modern sediments appear synchronous with the strong hydrolysis of soil during wet periods. A dozen terraces located in the borders of the lakes were sampled and studied. Seven radiocarbon dates were obtained on organic matter and shells. The time period concerned is between 2300 yr B.P and 400 yr B.P. The results show a high lake level at about 2300 yr B.P. The Lake Iffer was deeper by about 30 m from its current level. 1000 yr B.P probably marks the beginning of the decline with a drop in lake level of 20 m, which is ongoing in connection with climatic conditions become drier. MOROCCAN CLIMATE VARIABILITY BETWEEN EIGHTEENTH AND NINETEENTH CENTURY USING DOCUMENTARY SOURCES Brahim Damnati. UAE. Faculty of Sciences and Techniques-Tangier, Morocco E-mail address: [email protected]
There is only very limited climate information available from northern African countries based on documentary evidence. In Morocco, recent studies of logbooks for the period between 1727 and 1900 show much very interesting information. This climatic information was obtained from a wide variety of documentary sources such as private correspondence, brief relations describing extreme events, and particularly agricultural records (famine, floods.). Results of these studies indicate rainfall fluctuations, without abrupt changes, in the following alternating dry and wet phases: 1721-1724 dry, 1728-1729 wet, 1737-1738 dry, 1742-1744 dry, 1750 dry, 1776 dry, 1777-1778 wet, 1779-1782 dry, 1782-1783 wet, 1801-1816 wet, 1816-1817-1818 dry, 1825-1826 dry. Between 1727 and 1826, there were over six periods of drought, with a minimum of 13 years and a maximum period of 38 years. From 1826 to 1900 more than 9 dry periods were observed. If we compare these results with the results obtained by tree ring (Till and Guiot, 1990), there's a very interesting concordance. Till and Guiot (1990) published a 900-year reconstruction of OctoberSeptember precipitation for three different areas in Morocco, indicating a continuous tendency towards a wetter climate during the twentieth century, and drier conditions than present during the sixteenth, seventeenth and eighteenth century. THE USE OF FIRE FOR ECOSYSTEM MANAGEMENT: TRACKING THE EMERGENCE OF H. SAPIENS BEHAVIOURAL MODERNITY IN SOUTHERN AFRICA Anne-Laure Daniau. CNRS UMR PACEA-EPOC, Université Bordeaux 1, France E-mail address: [email protected]
It has been proposed that a greater control and more extensive use of fire was one of the behavioural innovations that emerged in Africa among early H. sapiens, favouring their spread throughout the world and determining their eventual evolutionary success. We would expect, if extensive fire use for ecosystem management were a component of the modern human technical and cognitive package, as suggested for Australia, to find major disturbances in the natural biomass burning variability associated with the occupation of Africa by H. sapiens. One of the aims of the TRACSYMBOLS project is to examine how key behavioural innovations emerged among H. sapiens in southern Africa, explore whether environmental variability influenced this development between 180 and 25 ka (Marine Isotope Stages 6 to 3), and establish if some of these innovations had an impact on African environments. Swift changes in environment in Africa during this period may have accelerated individual and general purpose social learning mechanisms that currently characterize humans. We will present preliminary results of the analysis of microcharcoal preserved in a deepsea core located off the Orange river's mouth that provides a record of the fire regime variability of this large river catchment basin. The direct correlation between marine and terrestrial (vegetation) climate proxies provides a unique opportunity to tackle fire regime variability in response to climate change and human adaptation. This approach has already been applied to Western Europe, where the fire regime follows the DansgaardOeschger climatic variability and appeared not controlled or influenced by Neanderthals or Anatomically modern populations.
PREDICTABILITY OF BIOMASS BURNING IN RESPONSE TO CLIMATE CHANGES Anne-Laure Daniau. CNRS UMR PACEA-EPOC, Université Bordeaux 1, France E-mail address: [email protected]
We used a worldwide compilation of w700 charcoal records to relate biomass burning to climate changes over the past 22 kyr. Much of the recorded variability reflects a global shift from low glacial to higher interglacial burning. The increase of global biomass burning starts earlier in the southern hemisphere than in the northern hemisphere, consistent with asynchronous warming shown by polar ice cores. Northern hemisphere burning increased through the Holocene while southern hemisphere burning initially declined and subsequently increased. Biomass burning was low in the northern tropics and high in the southern tropics in the early Holocene. These zonal trends are reproduced using an empirical function linking charcoal and time-varying temperature and precipitation minus evaporation (P-E) simulated using orbital, ice-sheet and greenhouse-gas forcing. This function shows fire increases with increasing temperature but peaks at intermediate levels of P-E. The same relationships are found by using an analysis of the spatial variations of contemporary burnt area and climate. This predictable response of fire to climate has serious implications on a warming Earth. AEOLIAN RECORDS OF ABRUPT ENVIRONMENTAL CHANGES IN SOUTHERN SIBERIA DURING MIDDLE-LATE HOLOCENE BASED ON THE RESEARCH IN THE LAKE BAIKAL REGION Lidia Danko. V.B. Sochava Institute of Geography SB RAS, Russian Federation E-mail address: [email protected]
The areas under study are situated in the southern and northeastern part of the Lake Baikal Region (southern Siberia). In the intermountain depressions, so-called Barguzinskaya Valley and Tunkinskaya Valley, local dune fields and loess-like sediments have formed. The present climate within these areas is continental, characterized by low precipitation (mean annual amount of 250-300 mm) and wide annual range of temperature. Six periods with formation of the aeolian deposits: earlier 6000, later 5000, from 2900 to 2400 and 2000 to 1600, about 800 and 400-500 cal. years BP, are recognized. It shows a periodical formation of the aeolian sediments under the conditions of a significant lowering of humidity. The buried soils serve as a proof for most humid phases. Consequently, sedimentation conditions did not remain permanent, evidencing environmental instability. The frequency and range of these events requires additional study, although the available records make it clear that the abrupt environmental changes were forced by climatic aridity. The aeolian events reconstruction has also been compared to vegetation dynamics derived from Lake Baikal pollen records [Tarasov et al., 2007]. According to this work relatively high score of the steppe biome occurs around 7500, 5500, 3000 and 1000-500 cal. BP. The similarities between the results may indicate that humidity fluctuations are regional character. It also is supposed that local aeolian records indicating a mainly dry condition in the Baikal Region as well in southern Siberia. The abrupt environmental changes, however, were mostly expressed in the local semiarid landscapes. A comparison our results with the weak monsoon episodes [Wang et.al, 2005; Xingqi et al., 2009] and climate changes in the central Asia [Xiaoping et al., 2004; Yang, 2009] shows simultaneous these events. Thus, initiation of aeolian activity in the Lake Baikal Region during Middle-Late Holocene was associated with large-scale circulation processes. BIOSTRATIGRAPHY OF THE LATE PLEISTOCENE (LATE NEOPLEISTOCENE) OF THE SOUTHERN URALS REGION: CORRELATION WITH OTHER REGIONS Guzel Danukalova. Institute of Geology, Russian Federation E-mail address: [email protected]
Published and unpublished material dealing with the stratigraphy of the Late Pleistocene (Late Neopleistocene according to the Russian stratigraphic scheme) of the Southern Urals is summarized. The results of the mammalian, mollusc and palynological investigations have been used in
Abstracts / Quaternary International 279-280 (2012) 9–120
the reconstruction of the palaeoenvironments and provide the basis for the stratigraphical subdivision. The local stratigraphic subdivisions are named: Kushnarenkovo, Saigatka, Tabulda, Kudashevo. The stratigraphic positions of the main Upper Neopleistocene localities and their precise definitions are given. The beginning of the Late Neopleistocene coincided with a phase of incision of the river valley and, probably with a significant uplift. Fluvial sediments formed the second terraces above the floodplain, but were almost entirely destroyed by the subsequent erosion. The climate was warm and wet. The Saigatka time was cold. Small hanging glaciers developed in the mountains. Altitudes of the mountains were close to their present-day values. River erosion was slow. Floodplain sediments are preserved in small areas; they constitute the upper parts of the second terraces. In Tabulda time, the incision of the hydrographic network increased. This was related with the uplift of the Southern Urals. Subsequently, the incision was replaced by lateral erosion, which destroyed the second terrace. Fluvial sediments now form the lower parts of the first terraces. The climate was moderately warm at that time. The Tabulda Horizon corresponds to the interglacial. The situation changed in the Late Neopleistocene which became colder. The southern Cisuralia region suffered deep seasonal frost penetration. Loess-like sediments form the upper parts of the first terraces and cover the watersheds; they contain cryogenic structures. There are known several Paleolithic sites. Local units are correlated with the stratigraphic schemes of the East European Platform, Lower Volga, Middle Urals, and Western European stratigraphic successions. MALACOLOGICAL CHARACTERISTIC OF THE MIDDLE PLEISTOCENE LOESS (MIS-6) OF THE BATAJNICA LOCALITY (SERBIA) Guzel Danukalova. Institute of Geology, Russian Federation E-mail address: [email protected]
The Batajnica loess section is situated 15 km NW of Belgrade on the right bank of the Danube river. The main aim of investigations in 2010 was to get the mollusc species characteristics during the Middle-Upper Pleistocene transition. Analysed deposits correspond to the upper part of the soil (VS1¼MIS 5), loess (VL2¼MIS 6) and the soil (VS2¼MIS 7). Every 15 cm of deposits had been sampled and washed with sieves of 0.75 mm. A total of 4817 mollusc shells of 13 terrestrial species families and 1 freshwater species were determined. Mollusc complex of VL2 is the most diverse in species and quantitatively: Succinia cf. oblonga, Cochlicopa lubrica, Cochlicopa sp., Pupilla muscorum, P. Bigranata, Pupilla sp., Vertigo pygmaea, Truncatellina cylindrica, Chondrula tridens, Chondrula sp., Vallonia costata, V. pulchella, Vallonia sp., Helicella striata, Granaria frumentatum, Granaria sp., Helicopsis sp., ? Oxychilus sp., Limax cf. maximus, Clausilia cf. dubia, Clausilia sp., Punctum pygmaeum, and Anisus sp. The upper part of the lower soil (VS1) contains shells of Cochlicopa sp., Pupilla muscorum, Pupilla bigranata, Pupilla sp., Vertigo pygmaea , Truncatellina cylindrica, Chondrula tridens, Chondrula sp., Vallonia costata, Vallonia pulchella, Vallonia sp., Granaria frumentatum, Granaria sp., Helicopsis sp., Limax cf. maximus. Few shells of Pupilla muscorum, Vertigo cf. pygmaea, Truncatula sp., Chondrula sp., Vallonia costata, Vallonia sp., Helicella striata, and Limax cf. maximus were extracted from the upper soil (VS2). Loess (VL2) corresponds to the cold interval of the global climate changes. At the same time molluscs (VL2) indicate moderate climate and open landscapes with small broadleaved forests. Mollusc complexes of VL2, VS1 and VS2 show almost the same species composition which suggests refugium existence at the investigated area. Contrary mollusc complexes (MIS 6) from Urals and Russian Plain have less species variety and have small individual quantity in comparison with Batajnica section. HURRICANE ACTIVITY DURING THE LATE HOLOCENE IN NEW ENGLAND, USA, BASED ON OPTICAL DATING Femke Davids. Aberystwyth University, United Kingdom E-mail address: [email protected]
Major hurricanes can be a cause of much loss of life, property and infrastructure. In the densely populated coastal regions of southern New
107
England, therefore, it is of the utmost importance to produce reliable predictions of hurricane activity. Since the instrumental and historical records are very short, long term predictions, on the scale of decades and centennials, present a challenge. The geological archive presents an opportunity to investigate long term variability. The storm surges associated with hurricanes can deposit sand overwash layers in coastal back barrier marshes or lakes. Davids et al. (2010) showed that these overwash layers can be successfully dated with optical dating: both with quartz as well as K-feldspar optically stimulated luminescence (OSL). This paper will present the optical dating results for three field sites within ca. 50 km of each other on the southern New England coastline. A number of radiocarbon ages provide independent age control for the prehistoric hurricane events. The results demonstrate that both prehistoric and historic hurricane events can be well correlated in these field sites and show two periods of increased hurricane activity during the last 3000 years. A HIGH RESOLUTION RECORD OF MAJOR STORMS AND HURRICANES DURING THE LAST MILLENNIUM IN OYSTER POND, NEW ENGLAND (USA), BASED ON MULTIPLE PROXIES Femke Davids. Aberystwyth University, United Kingdom E-mail address: [email protected]
Back barrier coastal lakes can preserve overwash events associated with major storms and hurricanes as distinctive sandy layers between organic mud deposits. Oyster Pond, which is situated on the southern coastline of New England, has a high sedimentation rate and is sensitive to storm surge inundation and has therefore preserved many overwash events. This paper will present the high resolution results of a study investigating the major storms and hurricanes preserved as overwash layers during the last millennium, based on radiometric dating (optical, radiocarbon, cesium and lead), pollen concentrations and grain size analysis of two sediment cores. There is good agreement for the major hurricanes from the 19th and 20th Centuries between the cores and the historical record. However, the Great Colonial Hurricane (AD 1635), which has been interpreted as a major hurricane from historical records, is not clearly present in this record even though this site is very sensitive to washover. Furthermore, this hurricane has been found in many other sites along the southern New England coastline. This paper will address the possible reasons for this discrepancy between records. EXPLORING MODERN IMPACTS ON UPLAND LANDSCAPE PROCESSES USING MULTIPROXY PALAEOENVIRONMENTAL RECONSTRUCTION TECHNIQUES Heather Davies. University of Plymouth, United Kingdom E-mail address: [email protected]
The modern period (w AD 1750 onwards) is often considered to be sufficiently described by historical records, and has tended to be relatively neglected by palaeoenvironmental research, the main focus of which is often millennial-scale environmental changes. British uplands have become the focus of a variety of projects in recent years to preserve important vegetation communities, prevent carbon loss and downstream flooding, and improve water quality. However, as long-term data on vegetation change, and the impacts of human land use on water quality, are often unavailable, setting restoration targets or making predictions for future change is difficult. The aim of this project is to create high-resolution multiproxy palaeoenvironmental records for the last 200-300 years from an upland catchment (Venford Reservoir) on Dartmoor (southwest England, UK) using sediment records from reservoir and peat cores. Through pollen and charcoal analysis vegetation and fire histories have been reconstructed along with diatom-inferred total phosphorus and pH levels. The results of the pollen and diatom palaeoecological analyses will be compared to explore whether changes in human land use coincide with shifts in water quality. Measurements of radio-isotope activity (210Pb and 137Cs) from the reservoir cores have provided evidence of catchment erosion possibly related to peat cutting. Initial results indicate that the 210Pb signal has been diluted in the most recent reservoir sediment, which occurs simultaneously with increased 137Cs activity, indicating that new material is being in-washed from the catchment. The results of the project