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Wetland environments have been important resources for human habitation since prehistoric times and in parts of northern Europe these have witnessed the construction of artificial islet settlements, known as 'crannogs' in Scotland and Ireland. This paper presents a high-resolution multi-proxy palaeoenvironmental study from the Loch of Leys, Aberdeenshire, Scotland, the site of a recently excavated crannog that provides a chronological context for its inhabitation. The combined datasets demonstrate that the first occupation from AD 20–210 coincided not only with a transitional phase from lake to wetland (mire) but also with the timing of the first major Roman campaigns in northeast Scotland. Techniques including microfossil analysis, geochemistry, IR-spectroscopy and physical properties integrated with archaeological and historical records have helped to better define both natural changes that took place in the wetland environment and human activity (agriculture, fires, metal working) spanning the Roman Iron Age through to the present. This has allowed a better understanding of the responses of existing Iron Age communities to Roman military activity (e.g. through continuity or change in land use) as well as the resources exploited in frontier zones during the Roman and post Roman eras. This has wider significance not just for Scotland but also for other parts of Europe that had similar frontiers and conflict zones during the Roman period. • Crannogs & phases of occupation during the Iron Age & early-post medieval periods. • Multiproxy techniques determine continuity and change beyond Roman frontiers. • Interdisciplinary approaches to understand landscapes, farming & metal working. • Geochemistry, colour, FTIR & palynology identifies wetland & cultural change. • Understanding the wider context of pre-post Roman influences on communities. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews recent progress in the use of linear dunes as ‘geoproxies’ of late Quaternary environmental change, summarises the challenges facing their use, and explores some potential solutions to these challenges. Large areas of the swathes of linear dunes which occupy the continental interior of southern Africa, Australia, and parts of central Asia and southern America currently have limited or negligible aeolian activity. They have been recognised as offering potential information about past environments for more than a century, but only with the widespread application of luminescence dating during the 1990s did they realistically start to offer the prospect of being an extensive, dateable proxy of late Quaternary palaeoenvironments and, possibly, palaeoclimates. Dating aeolian dune sands with luminescence methods is generally (although not always) relatively straightforward. Over the past twenty years, a large number (>1000) of luminescence ages have been added to the global dataset, yet there has also been significant criticism of some of the rationale underpinning much of the interpretation of the records derived. At the landscape scale, developments of arguably equal importance have come from improved geomorphological understanding based on the wider availability of remotely-sensed data and the paradigm of dunefield evolution as a self-organising complex system. Current challenges are identified in three key regions: incomplete understanding of how the process geomorphology of linear dunes affect the accumulation and preservation of sediment, a lack of clarity regarding the temporal and spatial scale of the response in a dynamic environmental setting and uncertainty surrounding the drivers of changing rates of net accumulation. Solutions to these challenges lie within diverse research methodologies. Certainly, further field study is required, with improvement required in understanding system responses to changing environmental stimuli at scales from sedimentological to landscape. In parallel, the full implications of complex systems approaches to aeolian geomorphology for linear dunes lag behind the adoption of the concept to some other dune forms (e.g. barchans); the relationship between observed dune complexity and age from field data complicates previous suggestions that dune patterning may be purely a function of development time. Parallel to this lies the need to improve interpretation of the results of dune geochronological studies; a suggestion is offered which aims to test the statistical significance of dune accumulation time-series by comparison with a modelled system with unchanging external forcing. Despite the initial promise of linear dune records as a revolutionary source of palaeoenvironmental information in drylands, the outcomes to date have been coarse, although still valuable, in resolution. Perhaps the most valuable realization has been that geomorphological understanding of these widespread landforms is incomplete. [Copyright &y& Elsevier]

Abstract: This paper reviews our current understanding of Quaternary climate and landscape changes in the desert areas of northern China, a key portion of the middle-latitude drylands on Earth. Combining earlier studies with our recent research and experience, we offer a comprehensive picture of the state of Chinese deserts during the Quaternary and, in the interest of enhancing future research, identify knowledge gaps and areas of uncertainty. Lacustrine deposits found over an area ranging from China’s western Taklamakan Desert to the eastern Hunshandake Sandy Lands suggest that extensive lakes occurred in China’s deserts during the Pleistocene. Analysis of digital elevation models from SRTM (Shuttle Radar Topography Mission) data supports this interpretation and shows the significant extent of these former lakes. New estimates of mean annual evaporation of ca. 1000 mm from lake surfaces and ca. 100 mm from land surfaces, confirms that local and regional rainfall is critical for maintenance of desert lakes in this temperate zone, especially during intervals when the mean annual rainfall is more than 100 mm. Rapid shifts between sand seas and lakes in geologically and environmentally diverse settings suggest that the drylands of China are very sensitive ephemeral systems, and not long-lasting as previously thought. Available chronologies suggest that there were large lakes in the western Taklamakan Desert and the Chadamu Basin during MIS (Marine Isotope Stage) 3, at ∼30 ka, probably related to a period of strong influence of northern hemispheric westerly winds. Channels and elevation models revealed by SRTM data and remains of lacustrine sediments also indicate that there was a large lake in the Hunshandake Sandy Lands in the eastern portion of the desert belt during the Quaternary. There is significant evidence that during the middle Holocene strong summer monsoons led to a relatively large increase in moisture availability in the entire desert belt of northern China. Lacustrine records from the Badain Jaran Desert in western Inner Mongolia suggest that it was generally dry before 10 cal ka, becoming wetter from 10 to 4 cal ka, and dry again afterwards. Study of palaeosols widely occurring in dune stratigraphy in the eastern portion of the desert belt, suggests that there was a period of wet and warm climate in this region during the mid-Holocene Optimum, at a minimum between 6 ka and 4 ka, but possibly lasting longer. Recent observations dealing with the generation and transport of dust from Central Asia indicate that the causal relationship between sand seas and loess sequences is not as close as previously assumed. These results suggest that there is an urgent need to examine whether the frequency and amplitude of climatic variation in Chinese deserts are somehow similar to that having occurred in the Sahara Desert of North Africa. Deserts in northern China were also important focal regions for Neolithic cultures during intervals when environmental conditions supported a denser vegetative cover. There is evidence that some areas of woody vegetation to the west of Badain Jaran Desert were deforested by humans by ca. 4000 yr B P, although it is still debatable whether humans have had a significant impact in other areas at that time. Opinions on the severity of desertification vary and are sometimes contradictory due to the lack of long-term, field-based, investigations. [Copyright &y& Elsevier]

The Late Upper Palaeolithic of Europe, particularly the Last Glacial Maximum (LGM: 26-19 kyr cal BP), was a time of dramatic climatic changes. Fauna, and the humans that preyed on them, were forced to adapt their behaviours in response to climate changes to survive. The Cantabrian Region of northern Spain was continuously inhabited during this period when many other areas of Europe were inhospitable. The site of Las Caldas (Asturias) was repeatedly occupied by hunter-gatherers during the Solutrean (26.1–20.3 kyr cal BP) and Magdalenian (18.5–14.3 kyr cal BP). This paper uses δ13C and δ15N stable isotope analysis of red deer (Cervus elaphus) and Spanish ibex (Capra pyrenaica) remains to reconstruct past environments, ungulate niches and habitats, and to understand how this impacted on their availability as a prey source. Results show that during the Solutrean, cold and potentially wet LGM conditions were experienced and ibex lived in lower altitudes, likely due to reduced vegetation, and even small glaciers on the higher mountain slopes. Improved environmental conditions in the Magdalenian allowed ibex to live in their preferred habitat of higher altitudes. Ameliorated Late Glacial conditions correspond with changing economic hunting strategies at the site. Humans exploited wider ecological zones, over larger distances, which coincides with population growth, and greater connectivity across the Cantabrian region. This research highlights the importance of characterising the complex interactions between humans, animals and environments during the Late Pleistocene and how they responded to rapidly changing environmental conditions. • Bone collagen δ13C and δ15N values used to reconstruct environments and faunal niches between 26 and 14 kyr cal BP in N. Spain. • Harsh Solutrean conditions affected ibex habitats, and they moved to lower altitudes. • Improved Magdalenian conditions coincided with exploitation of wider ecological zones. • Increased Magdalenian human populations pressured resources, affecting subsistence strategies. [ABSTRACT FROM AUTHOR]

In this paper new palaeogeographic and archaeological data from the prehistoric cave Vela Spila on the island of Korčula in Croatia are combined with new realizations of two glacial isostatic adjustment models in order to present relative sea-level change scenarios confronting the inhabitants of the cave at different time slices and to show how they experienced and adapted to sea-level and climate change from the Late Pleistocene through the Holocene. Our results show that from the Late Upper Palaeolithic until the Mesolithic, humans in the study area would have experienced tens of metres of sea-level rise, at rates in some cases up to 12 mm per year, and, owing to the relatively flat morphology of the now submerged plains, hundreds of meters of horizontal coastline change in the plains to the north and south of the island. This evidence supports the hypothesis that the rapid loss of these plains likely contributed to the human abandonment of the cave after the Palaeolithic for about five thousand years, followed by significant changes in lifestyle and diet in the Mesolithic. Our results have important implications for the study of how past human groups, especially in vulnerable coastal areas, were affected by sea level, climate, and other environmental changes. Vela Spila represents a case study of how changing environment and rising seas can force significant alterations in human societies, even when there is no risk of inundation to settlement sites. • Vela Spila Cave site, Croatia, testifies how sea-level rise can force changes in human societies. • The cave was settled from the Late Upper Palaeolithic until the Neolithic. • In the study area humans experienced tens of metres of sea-level rise in their lifetime. • In the Late Upper Palaeolithic, abandonment of the cave was triggered by high rates of sea-level rise. • Stabilization of coastlines fostered the re-occupation of the cave at ca. 9.4 cal ka BP. [ABSTRACT FROM AUTHOR]