- Email: [email protected]
The ‘Neolithic’ in Borneo: a different model
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Abstracts / Quaternary International 279-280 (2012) 121–232
during more advanced stage of weathering the plagioclases and augites rarely show preservation of diminishing cores. Formation of enormous clays and related minerals indicate that the dolerite has been strongly to completely altered. During early stage of weathering of gabbro; labradorite is seen to be altered rapidly than augite. However, in the most advanced stage of weathering the augite is seen to alter rapidly than labradorite and as a whole gabbro is moderately to strongly altered. Camptonite (basic lamprophyre) in its early stages of weathering is not much altered but the minerals are seen to be intensely fractured. However in the most advanced stages of weathering the groundmass is seen to be highly altered while labradorite and augite crystals have become highly dirty with the formation of clayey material indicating strong to complete alteration. That rocks with high amount of glass (e.g. basalt and camptonite) weather more rapidly than the rocks with low glass content and the fine grained rocks weather more slowly than the coarse grained rocks. Gabbro shows effects of both mechanical and chemical weathering. In case of the fine grained rocks like basalt, as they contain plenty of glass, there is a little scope of expansion and contraction of minerals due to their tiny crystals. INVESTIGATING EUTROPHICATION IN HIGH ELEVATION LAKES IN THE UINTA MOUNTAINS, UTAH (USA) USING A MULTIPROXY APPROACH Elizabeth Hundey. University of Western Ontario, Canada
domesticated rice very early in the Holocene. It took several millennia for components of this ‘package’ to reach the interior of the island. MANGROVES IN SARAWAK, BORNEO, AND THE IMPACT OF CLIMATE AND SEA LEVEL CHANGE IN THE LATE PLEISTOCENE AND HOLOCENE Chris Hunt. Queen's University Belfast, United Kingdom E-mail address: [email protected]
Mangroves are key tropical ecosystems, essential as breeding grounds for marine fauna, as 'filters' preventing terrestrially-derived silt and pollutants reaching the sea, as preventers of marine erosion and as diverse ecosystems in their own right. They are highly mobile, migrating with sea-level change. Mangroves are under threat from 'reclamation' of coastlands for development, from logging, from agricultural expansion, from climate change and from the resultant sea-level change. The mangrove forests of Borneo are globally significant but many areas are under severe threat or already lost. This contribution synthesises palynological data from a number of published and unpublished studies to document the behaviour of the mangrove communities of Sarawak, Borneo during episodes of sea-level, climatic instability and human impact during the Late Pleistocene and Holocene. From this data, we derive some general models of mangrove behaviour.
E-mail address: [email protected]
Alpine environments of the western United States are threatened by atmospheric pollution and climate change. The Uinta Mountains, an eastwest range in Utah, USA, are located downwind of the Wasatch Front, a region of high industrial activity and expanding population. We use multiple proxies to investigate changes in algal production in alpine Uinta lakes, and to determine the impacts of increased nutrient loads from atmospheric deposition and climate warming. Lake sediment cores (w50 cm), dated using 210Pb and 137Cs, from six high-elevation (>3000 m a.s.l.) sites have been analyzed using loss on ignition (LOI) to determine percentage organics and visible reflectance spectroscopy (VRS) to measure sedimentary chlorophyll a concentrations. The relative contributions of terrestrial and aquatic organics to lake production were estimated using carbon-nitrogen ratios. These proxies combined provide a better understanding of the history of eutrophication than a single proxy. The percentage organics and chl a concentrations are relative values, and therefore can be affected by inorganic inputs from the catchment and subsequent changes in sedimentation rates. Changes in catchment vegetation and climate will affect erosion rates, sedimentation rates, and therefore, relative values. By taking into account sedimentation rates and calculating fluxes of proxies, when well-dated cores are available, we can better interpret changes in LOI or chl a. Using these proxies in combination, we determined that algal production remained relatively stable until the mid-1900s, after which time it began to increase, often reaching a magnitude not seen in the past several hundred years. The timing of eutrophication is coincident with the introduction of man-made fertilizers and rapid urbanization, but precedes the rapid increase of temperature observed in the southwest US beginning in the late 1970s.
INSTABILITY OF RESPONSE TO CLIMATE CHANGE BY TROPICAL LOWLAND FOREST: EVIDENCE FROM THE GREAT CAVE OF NIAH, SARAWAK Chris Hunt. Queen's University Belfast, United Kingdom E-mail address: [email protected]
Modelling of the response to climate change by tropical vegetation in island southeast Asia is still highly deterministic and based on very few empirical data, which means that we have very little basis for forecasting future trends, or reconstructing past vegetation patterns. The sequences in the Great Cave of Niah, Sarawak, Malaysian Borneo, provide an important new perspective on vegetational response to climate change in the tropical lowlands. Cyclic episodes of rapid climate change during the Late Pleistocene saw the repeated disaggregation of tropical vegetation communities and an individualistic response by species to varying degrees of thermal and water stress. These individualistic responses resulted in forests with very different dominant species during successive interstadials. There were also rather different vegetation patterns, some very open, some dominated by montane taxa, during successive stadials. At times, climate change was so abrupt that the vegetation was manifestly unstable and pioneer taxa became very important. ON THE MEASUREMENT OF LUMINESCENCE DATING IN DELTAIC FORESETS OF SOUTHERN ITALY: IMPLICATION OF REGIONAL UPLIFT RATE Sébastien Huot. Université du Québec à Montréal, Canada E-mail address: [email protected]
THE ‘NEOLITHIC’ IN BORNEO: A DIFFERENT MODEL Chris Hunt. Queen's University Belfast, United Kingdom E-mail address: [email protected]
Research in recent years has shown that, very soon after first colonisation of Borneo in the Late Pleistocene, human hunter-gatherers engaged with a diverse suite of wild food plants. While groups such as the Penan still follow a hunter-gatherer lifestyle today, others had (and some still have) what some accounts have interpreted as Neolithic-style swidden agriculture at European contact. In the early years of the 20th Century, however, a more sophisticated observer, Lilian Gibbs, realised that alongside the agricultural systems instantly recognisable to westerners as farming, widespread rain-forest manipulation (‘arboriculture’) had been in place since 'time immemorial'. New evidence shows that the ‘Neolithic package’ in Borneo appears to have been a complex of intensively-managed indigenous plants, supplemented in coastal areas by imported species including
The Calabrian peninsula, in southern Italy, currently experiences horizontal and vertical tectonic motions. Evidences suggest that it began a few millions years ago. The CALARCO project seeks to identify and model the driving mechanisms behind these tectonic motions, to assess their variation in time, and its effects on the current landscape. The objective of this contribution is to establish a chronology, by optically stimulated luminescence, for the various fossilized shorelines, located in the Crati Valley of Calabria. Those surfaces are expected to result from high Interglacial sealevel stand. Results from the Crotone basin will also be presented. We observed luminescence from K-feldspar rich minerals extracted from those sediments. Anomalous fading was found to be w 3.1 %/decade. The dose rate correction method was applied to correct the laboratory-induced growth curve for the effect of fading. We also measured a sample for which we presume, from empirical geological evidence, has reached saturation in its natural luminescence. Its natural luminescence lies at 15% and 2% below the saturation level of the laboratory growth curve, respectively before and
Abstracts / Quaternary International 279-280 (2012) 121–232
during more advanced stage of weathering the plagioclases and augites rarely show preservation of diminishing cores. Formation of enormous clays and related minerals indicate that the dolerite has been strongly to completely altered. During early stage of weathering of gabbro; labradorite is seen to be altered rapidly than augite. However, in the most advanced stage of weathering the augite is seen to alter rapidly than labradorite and as a whole gabbro is moderately to strongly altered. Camptonite (basic lamprophyre) in its early stages of weathering is not much altered but the minerals are seen to be intensely fractured. However in the most advanced stages of weathering the groundmass is seen to be highly altered while labradorite and augite crystals have become highly dirty with the formation of clayey material indicating strong to complete alteration. That rocks with high amount of glass (e.g. basalt and camptonite) weather more rapidly than the rocks with low glass content and the fine grained rocks weather more slowly than the coarse grained rocks. Gabbro shows effects of both mechanical and chemical weathering. In case of the fine grained rocks like basalt, as they contain plenty of glass, there is a little scope of expansion and contraction of minerals due to their tiny crystals. INVESTIGATING EUTROPHICATION IN HIGH ELEVATION LAKES IN THE UINTA MOUNTAINS, UTAH (USA) USING A MULTIPROXY APPROACH Elizabeth Hundey. University of Western Ontario, Canada
domesticated rice very early in the Holocene. It took several millennia for components of this ‘package’ to reach the interior of the island. MANGROVES IN SARAWAK, BORNEO, AND THE IMPACT OF CLIMATE AND SEA LEVEL CHANGE IN THE LATE PLEISTOCENE AND HOLOCENE Chris Hunt. Queen's University Belfast, United Kingdom E-mail address: [email protected]
Mangroves are key tropical ecosystems, essential as breeding grounds for marine fauna, as 'filters' preventing terrestrially-derived silt and pollutants reaching the sea, as preventers of marine erosion and as diverse ecosystems in their own right. They are highly mobile, migrating with sea-level change. Mangroves are under threat from 'reclamation' of coastlands for development, from logging, from agricultural expansion, from climate change and from the resultant sea-level change. The mangrove forests of Borneo are globally significant but many areas are under severe threat or already lost. This contribution synthesises palynological data from a number of published and unpublished studies to document the behaviour of the mangrove communities of Sarawak, Borneo during episodes of sea-level, climatic instability and human impact during the Late Pleistocene and Holocene. From this data, we derive some general models of mangrove behaviour.
E-mail address: [email protected]
Alpine environments of the western United States are threatened by atmospheric pollution and climate change. The Uinta Mountains, an eastwest range in Utah, USA, are located downwind of the Wasatch Front, a region of high industrial activity and expanding population. We use multiple proxies to investigate changes in algal production in alpine Uinta lakes, and to determine the impacts of increased nutrient loads from atmospheric deposition and climate warming. Lake sediment cores (w50 cm), dated using 210Pb and 137Cs, from six high-elevation (>3000 m a.s.l.) sites have been analyzed using loss on ignition (LOI) to determine percentage organics and visible reflectance spectroscopy (VRS) to measure sedimentary chlorophyll a concentrations. The relative contributions of terrestrial and aquatic organics to lake production were estimated using carbon-nitrogen ratios. These proxies combined provide a better understanding of the history of eutrophication than a single proxy. The percentage organics and chl a concentrations are relative values, and therefore can be affected by inorganic inputs from the catchment and subsequent changes in sedimentation rates. Changes in catchment vegetation and climate will affect erosion rates, sedimentation rates, and therefore, relative values. By taking into account sedimentation rates and calculating fluxes of proxies, when well-dated cores are available, we can better interpret changes in LOI or chl a. Using these proxies in combination, we determined that algal production remained relatively stable until the mid-1900s, after which time it began to increase, often reaching a magnitude not seen in the past several hundred years. The timing of eutrophication is coincident with the introduction of man-made fertilizers and rapid urbanization, but precedes the rapid increase of temperature observed in the southwest US beginning in the late 1970s.
INSTABILITY OF RESPONSE TO CLIMATE CHANGE BY TROPICAL LOWLAND FOREST: EVIDENCE FROM THE GREAT CAVE OF NIAH, SARAWAK Chris Hunt. Queen's University Belfast, United Kingdom E-mail address: [email protected]
Modelling of the response to climate change by tropical vegetation in island southeast Asia is still highly deterministic and based on very few empirical data, which means that we have very little basis for forecasting future trends, or reconstructing past vegetation patterns. The sequences in the Great Cave of Niah, Sarawak, Malaysian Borneo, provide an important new perspective on vegetational response to climate change in the tropical lowlands. Cyclic episodes of rapid climate change during the Late Pleistocene saw the repeated disaggregation of tropical vegetation communities and an individualistic response by species to varying degrees of thermal and water stress. These individualistic responses resulted in forests with very different dominant species during successive interstadials. There were also rather different vegetation patterns, some very open, some dominated by montane taxa, during successive stadials. At times, climate change was so abrupt that the vegetation was manifestly unstable and pioneer taxa became very important. ON THE MEASUREMENT OF LUMINESCENCE DATING IN DELTAIC FORESETS OF SOUTHERN ITALY: IMPLICATION OF REGIONAL UPLIFT RATE Sébastien Huot. Université du Québec à Montréal, Canada E-mail address: [email protected]
THE ‘NEOLITHIC’ IN BORNEO: A DIFFERENT MODEL Chris Hunt. Queen's University Belfast, United Kingdom E-mail address: [email protected]
Research in recent years has shown that, very soon after first colonisation of Borneo in the Late Pleistocene, human hunter-gatherers engaged with a diverse suite of wild food plants. While groups such as the Penan still follow a hunter-gatherer lifestyle today, others had (and some still have) what some accounts have interpreted as Neolithic-style swidden agriculture at European contact. In the early years of the 20th Century, however, a more sophisticated observer, Lilian Gibbs, realised that alongside the agricultural systems instantly recognisable to westerners as farming, widespread rain-forest manipulation (‘arboriculture’) had been in place since 'time immemorial'. New evidence shows that the ‘Neolithic package’ in Borneo appears to have been a complex of intensively-managed indigenous plants, supplemented in coastal areas by imported species including
The Calabrian peninsula, in southern Italy, currently experiences horizontal and vertical tectonic motions. Evidences suggest that it began a few millions years ago. The CALARCO project seeks to identify and model the driving mechanisms behind these tectonic motions, to assess their variation in time, and its effects on the current landscape. The objective of this contribution is to establish a chronology, by optically stimulated luminescence, for the various fossilized shorelines, located in the Crati Valley of Calabria. Those surfaces are expected to result from high Interglacial sealevel stand. Results from the Crotone basin will also be presented. We observed luminescence from K-feldspar rich minerals extracted from those sediments. Anomalous fading was found to be w 3.1 %/decade. The dose rate correction method was applied to correct the laboratory-induced growth curve for the effect of fading. We also measured a sample for which we presume, from empirical geological evidence, has reached saturation in its natural luminescence. Its natural luminescence lies at 15% and 2% below the saturation level of the laboratory growth curve, respectively before and