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While mean grain size of sensitive component in muddy sediments from Chinese coastal seas was widely used as a proxy for reconstruction of the East Asian winter monsoon (EAWM) strength, many intractable problems still remain concerning the discrepancies in different studies. This paper provides a comprehensive overview of recent researches on the reconstruction of Holocene EAWM strength using sensitive grain size (SGS) in muddy sediments from the Chinese coastal seas. In the present study, 15 time-series of SGS in sediments from six mud areas are included. These records are summarized and compared during the last 8000 years, 3000 years and 150 years, respectively. The results show that trends of SGS time-series are inconsistent at millennial, multi-centennial and decadal time scales. The inconsistencies could be partly caused by age uncertainties and chosen SGSs. More important, grain size characteristics in sediments from some mud areas could be influenced by factors other than coastal currents driven by EAWM, such as sedimentary environments, riverine runoff and storms. Thus SGS of muddy sediments should be used with caution when reconstructing winter monsoon strength, especially those in the northern Yellow Sea and near the Yangtze River estuary. [ABSTRACT FROM AUTHOR]

The paper comprises data from 27 case studies to assess large-scale human-vegetation interferences in the Carpathian region during the Mid-Holocene. The main focus is put on herding-related vegetation changes and climate influences are addressed. The publications reviewed are based on sediment sequences which provide C 14 -dated pollen records, charcoal and geochemical data. Based on a semi-quantitative approach pollen of secondary indicator species and arboreal pollen values were combined in a fuzzy model to assess the intensity of herding-related vegetation changes. The model was applied for 20 selected case studies. The data from the remaining seven sites as well as geochemical and charcoal data were used to validate the results of the standardized evaluation. Speleothem δ 18 O and δ 13 C records from Hungary and Romania were used as independent proxies to align Holocene climate development. The results were regionalized and trends of herding-related vegetation change are presented for the Southern Carpathians and Apuseni Mountains, for the Eastern Carpathians and for Hungary. Mean distances between included archives and prehistoric settlement sites were calculated as indicator for the marginality of the environmental archives. In all regions, absolute values for herding indication are low. Phases of changing herding impact on the landscape can be observed for the Southern Carpathians and Apuseni Mountains as well as for Hungary. In the Southern Carpathians and Apuseni Mountains increased herding activities can be traced for the Early Chalcolithic and the Late Bronze Age. The first phase is contemporary with an intensification of the use of secondary products. In Hungary herding impact is in accordance with prehistoric settlement development. Widely increased herding indications date to the Late Chalcolithic and the Early Bronze Age. In the Eastern Carpathians, interference of climate influences and human impacts occurred. [ABSTRACT FROM AUTHOR]

This paper considers the results of comprehensive lithological, biostratigraphic, and geochemical investigation of sediments in Khara-Nur Lake (Eastern Sayan Mountains) situated in the area of the greatest Holocene eruptions in the Central Asia Region. The age of the basal sediment layer is estimated at 6881 ± 53 years. The local natural environment and climate have undergone great changes since that time. The Holocene volcanic events did not exert a catastrophic impact on the regional landscape, but they caused dramatic changes in the local vegetation. The well-defined correlation of the regional events with the well-known records of the natural environment in the Northern Hemisphere is indicative of the decisive influence of global atmospheric circulation on restructuring the landscape and climate system in the Zhom-Bolok Region in the Middle-Late Holocene. [ABSTRACT FROM AUTHOR]

It is widely accepted that climate has a strong impact and exerts important feedbacks on erosional processes and sediment transport mechanisms. However, the extent at which climate influences erosion is still a matter of debate. In this paper we test whether frost-cracking processes and related temperature variations can influence the sediment production and surface erosion in a small catchment situated in the eastern Italian Alps. To this extent, we first present a geomorphic map of the region that we complement with published 10 Be-based denudation rates. We then apply a preexisting heat-flow model in order to analyze the variations of the frost-cracking intensity (FCI) in the study area, which could have controlled the sediment production in the basin. Finally, we compare the model results with the pattern of denudation rates and Quaternary deposits in the geomorphic map. The model results, combined with field observations, mapping, and quantitative geomorphic analyses, reveal that frost-cracking processes have had a primary role in the production of sediment where the intensity of sediment supply has been dictated and limited by the combined effect of temperature variations and conditions of bedrock preservation. These results highlight the importance of a yet poorly understood process for the production of sediment in mountain areas. [ABSTRACT FROM AUTHOR]

The Levant, a transition zone between the temperate Mediterranean domain and subtropical deserts, is a key area to study the latitudinal migrations of zonal climatic belts in response to glacial-interglacial conditions. The region underwent large climatic shifts during the Late Quaternary, with dramatic impacts on water resources and human populations. This paper presents the unique long-term hydroclimatic record (ca. 400 ka) from Northern Levant, derived from a sediment core taken from a small tectonic basin of northern Lebanon, the currently wettest area of the Levant. Combined biotic (pollen, biologic aquatic remains) and abiotic proxies (sediment properties, carbonate oxygen isotopes) reveal relatively high water availability during interglacials and generally drier glacials periods during the past four climate cycles. These general trends are in line with pollen records from southeastern and near east Mediterranean areas, but differ from some paleohydrological records from the southern Levant. Southward migrations of the rain-bearing mid-latitude westerlies during glacial periods and regional land topography are likely to explain the observed regional climate signatures. In addition, distinctive climate signatures of the successive wetter/drier intervals reflect interactions between global forcing (insolation, atmospheric greenhouse gas concentration), eastern Mediterranean Sea surface conditions intimately linked to North Atlantic climate and to ice-sheet and sea-ice extent at high northern latitudes, land topography, and local hydrogeological processes. Our record brings new benchmarks for understanding the spatial heterogeneity of eastern Mediterranean responses to global climate changes. [ABSTRACT FROM AUTHOR]