- Email: [email protected]
Quaternary evolution of the Vienna Basin (Austria) – reconstruction through luminescence dating
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Abstracts / Quaternary International 279-280 (2012) 121–232
ice-sheet ocean interactions have been reconstructed from late in MIS 23 to 19 (c. 910-750 ka) at IODP Site U1313 in the North Atlantic. Continuous high-resolution stable isotope (oxygen and carbon) records from benthic and planktonic foraminifera have been reconstructed, allowing the assessment of the phase relationship between surface- and deep-water signals. These results permit preliminary discussion of the magnitude of surface- and deep-water changes during glacial/interglacial transitions and the interglacials themselves. Special emphasis will be placed on constraining the origin and characteristics of millennial-scale variability in North Atlantic sea surface and deep-water hydrography during MIS 19, considered a potential astronomical analogue for the Holocene and its future evolution, and the preceding interglacial MIS 21, a rather climatically unstable interglacial period within the mid-Pleistocene climate shift. We will discuss the climate differences between MIS 19 and 21, climate variability within these interglacials and attempt to establish their intensity and duration.
history traits of the dominant tree species. Preliminary results from the two datasets indicate that the greatest changes in turnover and forest composition including a change in forest type were recorded between 6000-4000 yr BP and during the last 1000 yr BP. The first was linked to more pronounced climate changes and fire disturbances, whereas the second interval was primarily driven by human impact. Results also show that interval of low compositional turnover (i.e., stability) appear to be concurrent with traits of the dominant tree species (Fagus sylavtica), rather than with diversity. Our data thus suggest that managing the forest stability would be better achieved by focussing on protection of key species with specific functional traits rather than the preservation of overall species diversity.
AGRO-PASTORALISM AND VERTICAL TRANSHUMANCE AT THE TIME OF THE NEOLITHIC ALPINE ICEMAN “ÖTZI”
Markus Fiebig. Institute of Applied Geology / University of Natur, Austria
Daniela Festi. University of Innsbruck, Austria
The Northern Alpine Foreland (NAF) comprises the archetype regions for the classical subdivision of the (Alpine) Quaternary. 20 years of correlation work by a working group (AGAQ) confirms that correlations on the base of a local morphological system are contradictory. A reason for disagreement is related to different landscape types even in the NAF itself. The morphology in the western part of NAF was lowered by partly more then 700 m during the Quaternary due to strong fluvial incision and glacial over-deepening. Incision and over-deepening in the eastern NAF was lesser, thus, old peneplains were preserved there throughout the Quaternary and even erosive fluvioglacial sequences are in superposition (e.g. Munich gravel plain, Traun-Enns region etc.). The Iller glacier area at the transition between western and eastern NAF was supposed to be the best compromise for correlation. Moderate but continuous fluvial incision created there a terrace stair case which was considered to be the most complete sequence of the (Alpine) Quaternary. Correlations of middle and early Pleistocene parts of this sequence to western and eastern NAF are still in dispute simply because the morphology is not directly comparable. During 20 years of correlation work of the AGAQ community unquestionable correlations was possible only if independent evidence, e.g. type fossils or physical ages, were available. New approaches to Quaternary correlation should not try anymore to correlate local morphologies (like the Iller sequence) to different areas but should focus on independent evidence like biostratigraphy or chronostratigraphy.
E-mail address: [email protected]
The practice of alpine summer farming and transhumance deeply changed and redesigned the landscape of the high altitudes in the Alps. Despite its great importance, it is still not clear when humans first adopted this subsistence strategy and what were the triggering factors leading to its development. In this context a case study from the Italian-Austrian eastern Alps is presented. In the frame of the research conducted on the Neolithic Alpine Iceman (5300-5100 yr cal BC) palynological analyses provided a first indication of possible pasture activity during the Neolithic in the mountain area where the Iceman was discovered. It has therefore been suggested that the Iceman had been involved in a local vertical transhumance between the Vinschgau valley bottom (his site of origin) and the high altitudes north of the main Alpine ridge. In order to scrutinize this hypothesis a multi-proxy study has been developed, aiming to reconstruct the former environmental and climatic situation of the Vinschgau, as well as the entity of the human occupation and the subsistence strategy in use at that time. In the valley the study focuses on the Copper Age site of Latsch (potential village of origin of the Iceman), while in the uplands pollen and fire history analyses are performed together with archaeological excavations on an altitudinal transect following the traditional transhumance route. Results of the investigation on Latsch will be presented, including macro-remains, charcoals and isotopic analyses carried out on bones and teeth. Moreover, new results of paleoecological and archaeological analyses on the sites along the transhumance route will be discussed. EVALUATING THE ROLE OF LIFE HISTORY TRAITS AND DIVERSITY ON LONG-TERM STABILITY OF TEMPERATE FORESTS OF THE ROMANIAN CARPATHIANS Angelica Feurdean. University of Oxford, United Kingdom E-mail address: [email protected]
It has been long hypothesised that diverse communities are better capable to buffer environmental stress and that understanding the relationship between diversity, stability and resilience is crucial for assessing impact of future environmental change on regional biodiversity. However, many studies focusing on testing the relationship between stability and diversity have been concentrated on ecosystems with short generation time and manipulated experiments with results suggesting that the greater the diversity the more stable the ecosystem. In contrast, other studies but mainly those focused on long-lived plants (i.e., tree species), have also shown that it is the composition of the species rather than overall diversity that dictates the ecosystem functioning. Here, two longterm records (spanning the past 6000 years) from the temperate forests of Romania were examined with the aim to explore whether the interval where there was a stable forest composition (i.e. reduced compositional turnover) coincided with greatest palynological richness or with life
THE PARADIGMA OF CORRELATION ON THE BASE OF A LOCAL SEQUENCE – SOME PERSONAL INSIGHTS AFTER 20 YEARS OF WORKING GROUP ACTIVITIES
E-mail address: markus.fi[email protected]
QUATERNARY EVOLUTION OF THE VIENNA BASIN (AUSTRIA) – RECONSTRUCTION THROUGH LUMINESCENCE DATING Markus Fiebig. Institute of Applied Geology / University of Natur, Austria E-mail address: markus.fi[email protected]
The Vienna Basin is a pull-apart basin between the Alps and the Carpathians which subsided in the Miocene and inverted afterwards. Some of the Miocene faults got reactivated during the later course of the Quaternary, creating a tectonic mosaic of blocks and dislocating terraces of the Danube and other Quaternary sediments. The exact age of the Pleistocene sediments is practically unknown due to a lack of absolute ages. In order to gain a better understanding of the younger evolution of the Vienna Basin and the overall climatic conditions in the Alpine-Carpathian transition, several sites along the Gänserndorf Terrace were investigated and dated by means of luminescence. The sequences comprise Danube gravel bodies, silty and sandy overbank sediments and display features of tectonic and paleoclimatic activity. The luminescence ages range from Late Glacial up to c. 300 ka and refute some previous chronological assumptions. For instance, the prominent Gänserndorf Terrace, formerly assigned to MIS 6, appears to have been formed during MIS 8. Further, changes in fluvial dynamics, possibly related to climate change, are recorded in the overbank fines. From the luminescence ages we try to fit some parts of the puzzle of Quaternary terrace formation, climate change and tectonic evolution in the basin.
Abstracts / Quaternary International 279-280 (2012) 121–232
ice-sheet ocean interactions have been reconstructed from late in MIS 23 to 19 (c. 910-750 ka) at IODP Site U1313 in the North Atlantic. Continuous high-resolution stable isotope (oxygen and carbon) records from benthic and planktonic foraminifera have been reconstructed, allowing the assessment of the phase relationship between surface- and deep-water signals. These results permit preliminary discussion of the magnitude of surface- and deep-water changes during glacial/interglacial transitions and the interglacials themselves. Special emphasis will be placed on constraining the origin and characteristics of millennial-scale variability in North Atlantic sea surface and deep-water hydrography during MIS 19, considered a potential astronomical analogue for the Holocene and its future evolution, and the preceding interglacial MIS 21, a rather climatically unstable interglacial period within the mid-Pleistocene climate shift. We will discuss the climate differences between MIS 19 and 21, climate variability within these interglacials and attempt to establish their intensity and duration.
history traits of the dominant tree species. Preliminary results from the two datasets indicate that the greatest changes in turnover and forest composition including a change in forest type were recorded between 6000-4000 yr BP and during the last 1000 yr BP. The first was linked to more pronounced climate changes and fire disturbances, whereas the second interval was primarily driven by human impact. Results also show that interval of low compositional turnover (i.e., stability) appear to be concurrent with traits of the dominant tree species (Fagus sylavtica), rather than with diversity. Our data thus suggest that managing the forest stability would be better achieved by focussing on protection of key species with specific functional traits rather than the preservation of overall species diversity.
AGRO-PASTORALISM AND VERTICAL TRANSHUMANCE AT THE TIME OF THE NEOLITHIC ALPINE ICEMAN “ÖTZI”
Markus Fiebig. Institute of Applied Geology / University of Natur, Austria
Daniela Festi. University of Innsbruck, Austria
The Northern Alpine Foreland (NAF) comprises the archetype regions for the classical subdivision of the (Alpine) Quaternary. 20 years of correlation work by a working group (AGAQ) confirms that correlations on the base of a local morphological system are contradictory. A reason for disagreement is related to different landscape types even in the NAF itself. The morphology in the western part of NAF was lowered by partly more then 700 m during the Quaternary due to strong fluvial incision and glacial over-deepening. Incision and over-deepening in the eastern NAF was lesser, thus, old peneplains were preserved there throughout the Quaternary and even erosive fluvioglacial sequences are in superposition (e.g. Munich gravel plain, Traun-Enns region etc.). The Iller glacier area at the transition between western and eastern NAF was supposed to be the best compromise for correlation. Moderate but continuous fluvial incision created there a terrace stair case which was considered to be the most complete sequence of the (Alpine) Quaternary. Correlations of middle and early Pleistocene parts of this sequence to western and eastern NAF are still in dispute simply because the morphology is not directly comparable. During 20 years of correlation work of the AGAQ community unquestionable correlations was possible only if independent evidence, e.g. type fossils or physical ages, were available. New approaches to Quaternary correlation should not try anymore to correlate local morphologies (like the Iller sequence) to different areas but should focus on independent evidence like biostratigraphy or chronostratigraphy.
E-mail address: [email protected]
The practice of alpine summer farming and transhumance deeply changed and redesigned the landscape of the high altitudes in the Alps. Despite its great importance, it is still not clear when humans first adopted this subsistence strategy and what were the triggering factors leading to its development. In this context a case study from the Italian-Austrian eastern Alps is presented. In the frame of the research conducted on the Neolithic Alpine Iceman (5300-5100 yr cal BC) palynological analyses provided a first indication of possible pasture activity during the Neolithic in the mountain area where the Iceman was discovered. It has therefore been suggested that the Iceman had been involved in a local vertical transhumance between the Vinschgau valley bottom (his site of origin) and the high altitudes north of the main Alpine ridge. In order to scrutinize this hypothesis a multi-proxy study has been developed, aiming to reconstruct the former environmental and climatic situation of the Vinschgau, as well as the entity of the human occupation and the subsistence strategy in use at that time. In the valley the study focuses on the Copper Age site of Latsch (potential village of origin of the Iceman), while in the uplands pollen and fire history analyses are performed together with archaeological excavations on an altitudinal transect following the traditional transhumance route. Results of the investigation on Latsch will be presented, including macro-remains, charcoals and isotopic analyses carried out on bones and teeth. Moreover, new results of paleoecological and archaeological analyses on the sites along the transhumance route will be discussed. EVALUATING THE ROLE OF LIFE HISTORY TRAITS AND DIVERSITY ON LONG-TERM STABILITY OF TEMPERATE FORESTS OF THE ROMANIAN CARPATHIANS Angelica Feurdean. University of Oxford, United Kingdom E-mail address: [email protected]
It has been long hypothesised that diverse communities are better capable to buffer environmental stress and that understanding the relationship between diversity, stability and resilience is crucial for assessing impact of future environmental change on regional biodiversity. However, many studies focusing on testing the relationship between stability and diversity have been concentrated on ecosystems with short generation time and manipulated experiments with results suggesting that the greater the diversity the more stable the ecosystem. In contrast, other studies but mainly those focused on long-lived plants (i.e., tree species), have also shown that it is the composition of the species rather than overall diversity that dictates the ecosystem functioning. Here, two longterm records (spanning the past 6000 years) from the temperate forests of Romania were examined with the aim to explore whether the interval where there was a stable forest composition (i.e. reduced compositional turnover) coincided with greatest palynological richness or with life
THE PARADIGMA OF CORRELATION ON THE BASE OF A LOCAL SEQUENCE – SOME PERSONAL INSIGHTS AFTER 20 YEARS OF WORKING GROUP ACTIVITIES
E-mail address: markus.fi[email protected]
QUATERNARY EVOLUTION OF THE VIENNA BASIN (AUSTRIA) – RECONSTRUCTION THROUGH LUMINESCENCE DATING Markus Fiebig. Institute of Applied Geology / University of Natur, Austria E-mail address: markus.fi[email protected]
The Vienna Basin is a pull-apart basin between the Alps and the Carpathians which subsided in the Miocene and inverted afterwards. Some of the Miocene faults got reactivated during the later course of the Quaternary, creating a tectonic mosaic of blocks and dislocating terraces of the Danube and other Quaternary sediments. The exact age of the Pleistocene sediments is practically unknown due to a lack of absolute ages. In order to gain a better understanding of the younger evolution of the Vienna Basin and the overall climatic conditions in the Alpine-Carpathian transition, several sites along the Gänserndorf Terrace were investigated and dated by means of luminescence. The sequences comprise Danube gravel bodies, silty and sandy overbank sediments and display features of tectonic and paleoclimatic activity. The luminescence ages range from Late Glacial up to c. 300 ka and refute some previous chronological assumptions. For instance, the prominent Gänserndorf Terrace, formerly assigned to MIS 6, appears to have been formed during MIS 8. Further, changes in fluvial dynamics, possibly related to climate change, are recorded in the overbank fines. From the luminescence ages we try to fit some parts of the puzzle of Quaternary terrace formation, climate change and tectonic evolution in the basin.