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We describe the career of John Birks as a pioneering scientist who has, over a career spanning five decades, transformed palaeoecology from a largely descriptive to a rigorous quantitative science relevant to contemporary questions in ecology and environmental change. We review his influence on students and colleagues not only at Cambridge and Bergen Universities, his places of primary employment, but also on individuals and research groups in Europe and North America. We also introduce the collection of papers that we have assembled in his honour. The papers are written by his former students and close colleagues and span many of the areas of palaeoecology to which John himself has made major contributions. These include the relationship between ecology and palaeoecology, late-glacial and Holocene palaeoecology, ecological succession, climate change and vegetation history, the role of palaeoecological techniques in reconstructing and understanding the impact of human activity on terrestrial and freshwater ecosystems and numerical analysis of multivariate palaeoecological data. [ABSTRACT FROM AUTHOR]

The onset of prehistoric farming brought unprecedented changes to landscapes and their biodiversity. Past biodiversity patterns are broadly understood for different parts of Europe, and demonstrate trajectories that have been linked to prehistoric and historic demographic transitions, and associated land-use practices. To our knowledge, this paper is the first attempt to directly link evidence of agricultural practice from the archaeological record to biodiversity patterns. Records of fossil pollen are used to estimate plant and landscape diversity patterns, and novel approaches are employed to analyse 1194 harmonised archaeobotanical samples (plant macrofossil remains) spanning the prehistoric and Roman periods, from southern England. We demonstrate changes in the use of crops and gathered edible plants and non-linear trends in cultivation practices. Whilst, overall, cereal production is characterised by ever larger and extensive regimes, different trajectories are evident for most of early prehistory, the Middle Iron Age and the Late Roman period. Comparisons with the Shannon diversity of fossil pollen records from the same region suggest a positive relationship between developing agricultural regimes and landscape scale biodiversity during the prehistoric period. The Roman period represents a tipping point in the relationship between expanding agriculture and pollen diversity, with declining pollen diversity evident in the records from the region. [ABSTRACT FROM AUTHOR]

The nature and extent of past indigenous transformations in the Amazon basin is an actively debated topic, and one that has important implications for both conservation policy and the cultural heritage of its indigenous and traditional populations. The use of charcoal and phytoliths to measure past human impacts in non-lacustrine settings has become especially influential in this debate but has also generated disagreement among scholars regarding the possible limits of these proxies for detecting ancient land-use. To contribute empirical data to this issue, our paper presents the first attempt to study charcoal and phytolith signals from areas of modern indigenous land-use, in the Xingu Indigenous Territory, southern Amazonia. Our findings show that, while charcoal and early successional herb phytoliths are good indicators of land-use intensity, certain types of land-use leave subtler traces in the phytolith record that can hinder their detection. We demonstrate how using finer sampling resolution and comparing local proxy data on their own terms are necessary steps in order to identify trends in human land-use across time and space. [ABSTRACT FROM AUTHOR]

The vast diversity of present vegetation and environments that occur throughout South America (12°N to 56°S) is the result of diverse processes that have been operating and interacting at different spatial and temporal scales. Global factors, such as the concentration of CO2 in the atmosphere, may have been significant for high altitude vegetation during times of lower abundance, while lower sea levels of glacial stages potentially opened areas of continental shelf for colonisation during a substantial portion of the Quaternary. Latitudinal variation in orbital forcing has operated on a regional scale. The pace of climate change in the tropics is dominated by precessional oscillations of c. 20 kyr, while the high latitudes of the south are dominated by obliquity oscillations of c. 40 kyr. In particular, seasonal insolation changes forced by precessional oscillations must have had important consequences for the distribution limits of species, with potentially different effects depending on the latitude. The availability of taxa, altitude and human impact, among other events, have locally influenced the environments. Disentangling the different forcing factors of environmental change that operate on different timescales, and understanding the underlying mechanisms leads to considerable challenges for palaeoecologists. The papers in this Special Issue present a selection of palaeoecological studies throughout South America on vegetation changes and other aspects of the environment, providing a window on the possible complexity of the nature of transitions and timings that are potentially available. [ABSTRACT FROM AUTHOR]

Macroecology is a big-picture, statistical approach to the study of ecology. By focusing on broadly occurring patterns and processes operating at large spatial and temporal scales and ignoring localized and fine-scaled details, macroecology aims to uncover general mechanisms operating at organism, population and ecosystem levels of organization. Although such an approach is evident in writings dating from the mid- to late 1800s, not until 1989 was the domain of macroecology clearly articulated. Since then there has been an exponential growth in publications employing a macroecological perspective. Here we (1) briefly review the history of macroecology, with emphasis on cultural, scientific and technological innovations that made this approach possible, (2) highlight current developments in the field, including its increasing linkages with biogeography and other disciplines, and (3) point to likely future directions. We also touch upon methodological, statistical and institutional challenges faced by this and other highly interdisciplinary approaches. Our review of macroecology is especially timely, since it has been 20 years since the term was coined and the seminal paper published. [ABSTRACT FROM AUTHOR]

Frank Oldfield's immense contribution to palaeoenvironmental science is summarized in relation to: pollen analysis, vegetation history and peat stratigraphy; palaeolimnology and 210Pb dating; environmental magnetism, catchment-lake relationships and soil erosional history; multiproxy approaches; PAGES; and editing The Holocene. The tribute includes an introduction to the 14 other papers in this Special Issue, which were inspired in diverse ways by this remarkable scientist. [ABSTRACT FROM AUTHOR]

Around 4000 cal yr BP, Scots pine (Pinus sylvestris) suffered a widespread demise across the British Isles. This paper presents new information about P. sylvestris populations found in the Welsh Marches (western central Britain), for which the long-term history and origins are poorly known. Two new pollen records were produced from the Lin Can Moss ombrotrophic bog (LM18) and the Breidden Hill pond (BH18). The LM18 peat core is supported by loss-on-ignition, humification analysis and radiocarbon dating. Lead concentrations were used to provide an estimated timeframe for the recent BH18 record. In contrast to many other Holocene pollen records from the British Isles, analysis of LM18 reveals that Scots pine grains were deposited continuously between c. 6900–300 cal yr BP, at frequencies of 0.3–5.4%. It is possible that individual Scots pine trees persisted through the wider demise on thin soils of steep drought-prone crags of hills or the fringes of lowland bogs in the Welsh Marches. At BH18, the record indicates a transition from broadleaved to mixed woodland, including conifer species introduced around AD 1850 including Picea and Pinus. The insights from BH18 suggest that the current populations may largely be the result of planting. Comparison of the LM18 findings with other regional pollen records highlights consistent patterns, including a Mid-Holocene maximum (ca. 7000 cal yr BP), long-term persistence at low pollen percentages and a Late-Holocene minimum (ca. 3000 cal yr BP). These distinctive trends encourage further studies on refugial areas for Scots pine in this region and elsewhere. [ABSTRACT FROM AUTHOR]

This paper presents continuous, high resolution fossil pollen and microcharcoal records from Bo Langvlei, a lake in the Wilderness Embayment on South Africa's southern Cape coast. Spanning the past ~1300 years and encompassing the Medieval Climate Anomaly (MCA; c. AD 950–1250) and the Little Ice Age (LIA; c. AD 1300–1850), these records provide a rare southern African perspective on past temperature, moisture and vegetation change during these much debated periods of the recent geological past. Considered together with other records from the Wilderness Embayment, we conclude that conditions in the region during the MCA chronozone were – in the context of the last 1300 years – likely relatively dry (reduced levels of Afrotemperate forest pollen) and perhaps slightly cooler (increased percentages of Stoebe -type pollen) than present. The most significant phase of forest expansion, and more humid conditions, occurred during the transition between the MCA and the most prominent cooling phase of the LIA. The LIA is clearly identified at this locality as a period of cool, dry conditions between c. AD 1600 and 1850. The mechanisms driving the changes observed in the Bo Langvlei pollen record appear to be generally linked to changes in temperature, and changes in the influence of tropical circulation systems. During warmer periods, moisture availability was higher at Bo Langvlei, and rainfall was perhaps less seasonal. During colder periods, precipitation resulting from tropical disturbances was more restricted, resulting in drier conditions. While increased precipitation has been reported during the LIA from Verlorenvlei in the Western Cape as a result of an equatorward displacement of the westerly storm-track at this time, the opposing response at Bo Langvlei suggests that any increased influence of westerlies was insufficient to compensate for the concurrent reduction in tropical/local rainfall in the region. [ABSTRACT FROM AUTHOR]

This paper presents the results of pollen, diatom, charcoal, and sediment analyses from Lake Bol'shoye Zavetnoye, situated between the Gulf of Finland and Lake Ladoga on the Karelian Isthmus, north-western Russia. The main goal is to contribute to the discussion of Neolithic land use in north-eastern Europe. The article aims to answer questions related to Stone Age hunter-gatherer economy, ecology, and anthropogenic environmental impact through a comprehensive combination of multiple types of palaeoecological data and archaeological material. According to diatom data, Lake Bol'shoye Zavetnoye was influenced by the water level oscillations of Ancient Lake Ladoga during much of the Holocene. Intensified human activity and prolonged human occupation become visible in the Lake Bol'shoye Zavetnoye pollen data between 4480 BC and 3250 BC. During the final centuries of the Stone Age, a new phase of land use began, as several anthropogenic indicators, such as Triticum, Cannabis, and Plantago lanceolata appear in the pollen data and a decrease in Pinus values is recorded. In general, the results indicate that socio-cultural transformations could have taken place already from the mid-5th millennium BC onwards, including new ways of utilizing the environment, perhaps also in the field of subsistence, even though the livelihood was based on foraging throughout the period. [ABSTRACT FROM AUTHOR]

This paper presents an original palaeoparasitological study performed on samples from a sedimentary core in a peat bog (Asi Gonia, White Mountains, Crete, Greece). The aim of the study is to test the preservation and concentration of parasitic remains in peat sediments, to discuss animal presence around the site throughout the record, and to compare the results with other biomarkers of environmental history. In this aim, 22 sediment samples distributed between the Roman period and the present were processed and the residues were observed under light microscopy in search of parasitic markers (microscopic eggs or oocysts). The majority of the samples (86.4%) tested positive for the presence of helminth eggs. Several taxa were observed throughout the studied period, including Trichuris sp., Ascaris sp., Capillaria sp., Fasciola sp., Paramphistomum sp. and Macracanthorhynchus sp. The assemblage of parasite markers changes throughout the record and the variations show close correlations with previously published grazing indicators (fungal spores) and vegetation changes (pollen grains). This study sheds lights on animal associations and changing environments in the watershed over the past 2000 years. Indeed, we detected three main phases consisting of: Roman animal herding with pigs in an evergreen oak forest, then a more irregular but almost constant presence of ruminants during a second Byzantine and modern phase in a heather maquis landscape and, finally, present-day grazing in a phrygana/steppe landscape. These results highlight how palaeoparasitology can contribute to multi-proxy approaches in peat bog sedimentary sequences. [ABSTRACT FROM AUTHOR]

Identification of ecosystem turnover in the palaeo-vegetation record is important for understanding the resilience of ecosystems to past environmental change. There is uncertainty over the ability of different types of palaeo-vegetation proxies to detect ecosystem turnover. The aim of this paper is to compare the sensitivity of two palaeo-vegetation proxies – pollen and phytoliths – to changes within and between three key tropical South American ecosystems: evergreen forest, dry forest and savannah. A quantitative approach is used to assess the sensitivity of these two proxies to vegetation changes, based on the variability of proxy assemblages from 1-ha ecological plots in ecotonal south-west Amazonia. This modern dataset of proxy variability within evergreen forest, dry forest and savannah plots is then used to define thresholds for proxy variability which differentiate floristic changes within an ecosystem from ecosystem turnover. These thresholds are applied to two palaeo-vegetation records from NE Bolivia. Our results show that pollen is more sensitive than phytoliths to changes within evergreen forest, but phytoliths are more sensitive than pollen to changes within dry forest. Both proxies were equally sensitive to changes within the savannahs. These are important considerations for palaeoecologists selecting proxies for the study of ecosystem turnover in the palaeo-record. Application of the thresholds to the palaeo-record demonstrated the utility of this quantitative approach for assessing the magnitude of vegetation change in the palaeo-record. This quantitative approach is therefore a useful tool to improve the identification of ecosystem turnover in the palaeo-record. [ABSTRACT FROM AUTHOR]

Transhumance agriculture formed a key component of subsistence strategies in the Norse economies of the North Atlantic, with evidence of shielings or sæters found in Norway, Scotland, the Faroe Islands and Iceland. It is frequently assumed to have played a role in Norse Greenland, yet little enquiry has been made into such activity. This paper seeks to address this deficit, presenting the first palaeoenvironmental study of a suspected Greenlandic shieling site in the uplands of the former Norse Eastern Settlement. Pollen analysis, 14C and associated proxies are used to date and assess the environmental and landscape impact of shieling activity. Evidence for vegetation disturbance associated with Norse settlement is indicated from c. ad 985, but the shieling itself is interpreted as having been established somewhat later (cal. ad 1050–1150). Initially the site appears to have been used exclusively for grazing of livestock and there is tentative evidence for the use of burning to stimulate the spread of pastures. Pollen influx figures suggest the intensification, or initiation, of hay production c. cal. 1225–1325 reflecting either the spread of settlement from the lowland valleys, or evolution of the site into a full farm in response to population pressure. A reduction of human impact cal. ad 1300–1390 suggests a reversion to shieling activity, indicating similarities to transhumance in northern Iceland. Abandonment of the site dates to cal. ad 1325–1415 and is in agreement with previous evidence from Norse Greenland. [ABSTRACT FROM AUTHOR]

The long-term goal of pollen analysis has always been the reconstruction of past vegetation mosaics. However, the pollen signal is spatially integrated, and ecologically distinct vegetation structures can produce identical pollen signals. This paper proposes an iterative approach to reconstruction, the Multiple Scenario Approach, which involves creating a large number of hypothetical landscapes using a combination of deterministic and probabilistic 'rules' for plant placement coupled with environmental parameters such as topography, simulating the pollen assemblage produced by each, and comparing them statistically with a sedimentary pollen signal to identify possible reconstructions. The method expressly aims to find multiple possible reconstructions, and also gives some insight into the spatial aspects of the vegetation being reconstructed in addition to its composition. [ABSTRACT FROM AUTHOR]

The mixed semi-evergreen forests in lowland central equatorial Africa can contain many elements of secondary vegetation. This raises the question of what factors have determined the current forest composition in this region. Is this forest in the process of succession after natural climatic variation and/or anthropogenic disturbances in the past, or is it a stable forest type? This paper presents a multiproxy palaeoecological analysis of a sedimentary sequence taken from a small sedimentary basin located in logged semi-evergreen lowland forest in northern Congo-Brazzaville which addresses these questions. Analyses undertaken included fossil pollen, geochemical and microscopic charcoal. Geochemical results were interpreted as a proxy for rainfall, and showed that northern Congo has experienced changes in rainfall during the past 2580 years, while microscopic charcoal concentrations indicated increased burning from approximately 1240 cal. yr BP to the present. Analysis of the fossil pollen assemblages showed that although light-demanding taxa were a major constituent of this forest throughout the sequence, shade-tolerant taxa were more abundant in the forest prior to 1345 cal. yr BP. Increases in aridity and/or droughts after 1345 cal. yr BP, and an increase in fire after 1240 cal. yr BP resulted in a semievergreen forest with abundant pioneers that persisted with minor changes in composition during the last 900 years, even during a period of increased rainfall from 400 to 100 cal. yr BP. These data may guide conservation policy by predicting potential consequences of future climate change and the impact of logging. [ABSTRACT FROM AUTHOR]

This paper describes our recent attempt to isolate and analyse DNA from old plant remains of the common peatmoss Sphagnum fuscum retrieved from a peat core collected in the mire Fuglmyra, in central Norway. DNA was recoverable and usable from subfossilized (10-450 years old) plant remains of the peatmoss. A chloroplast (trnL) and two nuclear (ITS2 and RAPDf) regions were co-amplified from 80 samples of different ages. The RAPDf region was the only variable one with three different haplotypes found among five samples. Comparison of the ancient sequences with modern sequences found in the extant population occurring at the same site ascertained a genetic link between modern and fossil samples of this species. This retrieval of ancient DNA from subfossilized moss remains isolated from peat cores has important implications for the palaeoecology of peatmosses by allowing direct estimates of plant population dynamics in space and time. [ABSTRACT FROM AUTHOR]

The modern floristic composition of the principal raised bogs of Wales is significantly altered compared with their histories of development from the early to mid Holocene. This paper uses pollen and plant macrofossil records from two raised bogs together with previously published data from a further two sites to explore the key factors contributing to the present condition of Welsh ombrotrophic plant communities. Results show Betula and Molinia invasion is a recent feature of bog development in Wales. Previous Holocene ‘dry-phases’ were characterized by Ericaceae and Pinus establishment, supporting recent experimental evidence that Betula and Molinia encroachment is primarily a response to nitrogen (N) loading rather than desiccation on intact bogs. Several of the bogs featured in this study also show severe signs of structural damage, not only from peat cutting but, in the case of Cors Caron, from channel processes in the adjacent River Teifi. Radiocarbon dating and inter-site comparisons of peat accumulation rates show that Rhos Goch Common in particular has been heavily impacted by peripheral peat cutting, leading to dewatering, significant subsidence of its peat dome and the spread of hummock and high dry ridge communities. Finally, the decline and local extinction of Sphagnum austinii in bogs across Europe represents one of the most significant changes in ombrotrophic community composition in the late Holocene. Co-registered pollen and macrofossil evidence from Cors Caron demonstrates that increases in landuse intensity over the last 2000 years are temporally associated with reductions in the abundance of S. austinii and ultimately its local disappearance from the palaeoecological record. [ABSTRACT FROM AUTHOR]

Pollen analysis of a 48 m AMS radiocarbon-dated sediment sequence from the Guadiana estuary provides the first record of Lateglacial and Holocene vegetation history in the Algarve province of Portugal. This paper focuses on the record of terrestrial pollen taxa, which document a series of forest expansions and declines during the period 13 000 cal. BP to 1600 cal. BP and provide insights into climate evolution in southwestern Iberia. The main vegetation phases identified in the Guadiana valley are (1) Lateglacial interstadial (Allerød) forest with Quercus and Pinus under a temperate, moist, continental climate; (2) a Younger Dryas forest decline (Quercus) and expansion of pinewoods, xeric scrub and open ground habitats (with Juniperus, Artemisia, Ephedra distachya type, Centaurea scabiosa type) under arid and cold conditions; (3) an early Holocene forest/scrub/open-ground vegetation mosaic developing under a warm, dry and continental climate; (4) a maximum of Quercus forest and thermomediterranean evergreen taxa (Olea, Phillyrea, Pistacia) reflecting a warm, moist oceanic climate between c. 9000 cal. BP and c. 5000 cal. BP; and (5) the expansion of shrublands with Cistaceae and Ericaceae under a drier climatic regime and increasing anthropogenic activity since c. 5000 cal. BP. Holocene episodes of maximum climatic aridity are identified in the record of xerophytic taxa (Juniperus, Artemisia, Ephedra distachya type) centred around 10 200 cal. BP, 7800 cal. BP, 4800 cal. BP, 3100 cal. BP and 1700 cal. BP. Regional comparisons suggest a correlation of arid phases across southern Iberia and northwest Africa, which can be related to abrupt North Atlantic coolings (Bond events). [ABSTRACT FROM AUTHOR]

Dallund Sø, a lake on the island of Funen, Denmark, is positioned in a landscape that has been heavily impacted by human activities and land-use change over thousands of years. In 1998 a project was initiated to utilize a variety of palaeoecological analyses to investigate lake response to changing land use through the period of agricultural impact on the Danish landscape, i.e., the last 6000 years. This paper describes the overall aims of the study, the natural and cultural setting, sediment core collection, sampling and physical properties, the chronology and erosion history. The long-term changes in the terrestrial and aquatic ecosystem are assessed in the following papers in this Research set using (i) pollen, (ii) diatoms, macrofossils and Pediastrum and (iii) zooplankton. These papers are followed by a synthesis paper focusing on the linkage between land-use change and lake development. [ABSTRACT FROM AUTHOR]

This paper examines the importance of palynological site selection criteria, specifically basin size, for the detection of vegetation mosaics and small- or local-scale human activity within a spatially diverse, mosaic landscape. Using a site selection strategy which recognizes landscape patchiness, pollen analyses from three small peat basins (10-56 m diameter) in an open, exposed upland valley (>250 m OD) provide records which are sensitive to local vegetation mosaics and small-scale, localized agriculture. The results indicate c. 4000 [sup 14]C years (4400 cal. years) of land use, with spatial and temporal variations in the valley. Contrasts between the sequences suggest that local pollen production remains an important component of the pollen rain deposited in small peat basins, even in open environments; this is especially true of palynological 'agricultural indicators'. By comparison, sites with regional pollen source areas underestimate the spatial diversity of the upland landscape, and are insensitive to small-scale human activity in an environment where the fragmentary distribution of soils suitable for agriculture favoured a small-scale, dispersed pattern of farming. It is therefore essential to match the spatial resolution of pollen records with the grain size or scale of variations in the environment under investigation in order to sense the scale of mosaics in vegetation and agriculture within patchy landscapes. [ABSTRACT FROM AUTHOR]

This paper examines the mid- to late-Holocene (c. 6850-1160 cal. yr BP) environmental history of Sierra de Gádor in southern Spain. The local vegetation dynamics are reconstructed through the palaeoecological record obtained from a lacustrine deposit situated at 1530 m. Various hypotheses are considered to explain the vegetation dynamics apparent in the palaeoecological evidence, including climatic change, fire occurrence and human activity. Although the vegetation in this region is sensitive to climatic change, threshold events driven by ecological factors are also apparent. Climatic events include a thermo-mesophytic optimum with abundance of deciduous trees and maximum lake water level found from c. 6850 to 5500 cal. yr BP. In contrast, changes in the frequency of major fire episodes appear to have shaped interspecific relationships and vegetation change, especially from c. 4200 cal. yr BP onwards. Biotic properties of the ecosystem such as the inertia of established tree populations, interconnected with competition adjustments, appear also to have played a role. Over the last two millennia, overgrazing, combined with natural and/or human-set fires, appears to have pushed mountain forests over a threshold leading to the spread of grassland, thorny scrub, junipers and nitrophilous communities. [ABSTRACT FROM AUTHOR]

High rates of sediment accumulation in Lake Simbi, western Kenya, has enabled fine-resolution fossil assemblages to reveal short-term changes in vegetation cover between 4320 ± 250 yr BP and 2880 ± 90 yr BP. Pollen analysis of a 4.2 sediment core covering this period reveals a vegetation change around 3300 yr BP. Analysis of charcoal shows that wildfires were prominent prior to the pollen-inferred vegetation change. Remains of grass cuticles and grass phytoliths show an expansion of grasslands and an increase in the diversity of grass types following the period of extensive fires. Also following the period of wildfires and the vegetation change, there were shifts within the grass flora to more Chloridoid grass types and less Panicoid grass types. This paper addresses one of the major problems of environmental reconstruction in lowland savannah: namely differentiating palaeoecological changes within the Gramineae. [ABSTRACT FROM PUBLISHER]

This paper presents the anthracological results of Cova de la Guineu. This cave, which is located at the NE of the Iberian Peninsula, has provided charcoal samples from the early Neolithic to the Iberian period enabling the identification of different phases on the basis of flora assemblage interpretation. The results show how Mediterranean forests have been present since the early Holocene stages. At the early phases of the sequence the assemblage records dominant meso-screrophyllous taxa (deciduous Quercus, Taxus baccata), then thermophilous taxa (evergreen Quercus) spread, and finally a late phase of transformation dominated by thermophilous and heliophilous taxa (Mediterranean Pinus). The interpretation and discussion deals with the development and transformation of primary and secondary forests due to human disturbances and climatic variations. The anthracological record from Cova de la Guineu suggests that both elements were important and define the evolution of vegetation during the Holocene in the region. [ABSTRACT FROM AUTHOR]

The arrival in Australia of Europeans and the species they brought with them initiated a sharp decline in native mammalian biodiversity. Consequently, one-third of the original or pre-European terrestrial mammal fauna is now extinct or threatened with extinction. Although the distributional ranges of many Australian mammals have contracted markedly, modern distributions are frequently used as baselines for conservation management and understanding ecological requirements. However, these often poorly reflect pre-European distributions, particularly in areas where biodiversity declines were rapid and occurred soon after European arrival. Here we analyse two late Holocene mammalian assemblages from Fleurieu Peninsula, South Australia, and reconstruct the pre-European terrestrial non-volant mammal fauna. The region was previously estimated to have lost perhaps 30% of its original terrestrial non-volant mammal fauna, but our results indicate a loss of almost 50%. We provide the first local records of the murids Mastacomys fuscus, Pseudomys australis, P. gouldii, P. novaehollandiae and P. shortridgei, and confirm the past occurrence of the now-extinct Conilurus albipes. Our study contributes new knowledge of species biogeography and ecology and will help refine restoration targets. [ABSTRACT FROM AUTHOR]

Despite their huge extent, the peatlands of Russia are an under-exploited source of data on palaeoenvironmental change. We investigated the Holocene history of Staroselsky Moch, an ombrotrophic peatland in the Tver Region of European Russia by analysis of testate amoebae, peat physical properties, plant macrofossils and pollen. The peatland developed through a classic hydroseral succession in the early Holocene with a sharp decline in mineral input to 6200 cal. BC followed by an abrupt transition from fen to bog vegetation around 5500 cal. BC. Through the Holocene, the peatland has accumulated carbon at a mean apparent rate of 21.5 g C m−2 yr−1 suggesting that carbon accumulation rates in peatlands of European Russia lie close to the global average, and contrasting with a short sequence of eddy-covariance data which implies a net loss of carbon. The testate amoeba record shows considerable variability which may be driven by climate, but changes are not well replicated in the macrofossil or pollen data. We tentatively infer (1) a phase of early Holocene warming commencing around 7200 cal. BC, (2) dry peatland surface conditions c. 3700–3900 cal. BC, (3) a shift to wetter conditions from c. 3900 cal. BC, and (4) drier conditions from c. 400 cal. BC onwards. More robust and precise hydroclimatic reconstructions for this region will require the development of a regional transfer function and the replication of results between cores and sites. [ABSTRACT FROM AUTHOR]

We provide the first fossil pollen and charcoal analysis from the island of Gran Canaria (Canary Islands). The pollen record obtained from Laguna de Valleseco (870 m a.s.l.) spans the late Holocene (c. 4500–1500 cal. yr BP) and thereby captures the impact of human colonization. During the earliest period, pollen composition resembled contemporary thermophilous communities, with palms (Phoenix canariensis) and junipers (Juniperus cf. turbinata) being the dominant trees, suggesting that these elements were more widespread in the past. Vegetation in Valleseco began to change at around 2300 cal. yr BP, 400 years before the earliest archaeological evidence of human presence in the island (c. 1900 cal. yr BP). Our data show an increased frequency of fires at that time, coinciding with the decline of palms and the increase of grasses, indicating that humans were present and were transforming vegetation, thus showing that the demise of Gran Canaria’s forest began at an early point in the prehistoric occupation of the island. In the following centuries, there were no signs of forest recovery. Pollen from cultivated cereals became significant, implying the introduction of agriculture in the site, by 1800 cal. yr BP. The next shift in vegetation (c. 1600 cal. yr BP) involved the decrease of grasses in favour of shrubs and trees like Morella faya, suggesting that agriculture was abandoned at the site. [ABSTRACT FROM AUTHOR]

Peat deposits from wetlands in the Upper Zambezi Valley provide an important long-term window on ecosystem dynamics in the Kalahari basin during the late Holocene. We use fossil pollen and macro-charcoal extracted from peat cores contained in three wetland sites to examine the response of vegetation to regional climate change. We find that during the last 6 ka, internal ecosystem dynamics are more important than climate, as observed by independent records, in determining vegetation assemblage change. Fire was found to be a persistent and important component of this savanna landscape for the duration of the ecological record, but biomass burning has increased markedly over the last 1000 years. The vegetation of the Upper Zambezi Valley appears to have a larger grassland component in the last few hundred years suggesting a more open landscape today than at any other time in the last 6000 years. [ABSTRACT FROM AUTHOR]

Subfossil remains of various groups of organisms preserved in peat and sediment archives are commonly used to infer past environmental changes using transfer functions based on species composition. However, the changes in community structure can also be explored using the functional trait approach. Investigation of functional traits in palaeoecological records can inform about the mechanisms through which abiotic variables such as temperature or moisture impact communities. Moreover, changes in functional traits provide information about changes in ecosystem functioning and can potentially lead to the reconstruction of past processes at the ecosystem scale. Here, we use five key functional traits of arcellinid testate amoebae (TAs), a group of protozoa that are key actors in the microbial foodwebs in peatlands. We apply this approach to the subfossil TA Holocene record of four geographically independent peatlands from Alaska, Switzerland, Poland and Russia. We found that species with larger shells were frequently eliminated from the communities most likely as a result of a switch towards drier conditions. However, when conditions were wetter, species with large shells and species with small shells could coexist because they differed in their trophic niche (i.e. preys). Our results show direct but site-specific links between TA trait data and the depth to water table and pH data inferred from TA species composition. This suggests that past environmental changes influenced both species composition and community function in these ecosystems. Overall, this study demonstrates that species- and trait-based approaches yield complementary information on past environmental changes. For instance, while taxonomic approaches reveal the changes in community composition over time, investigation of traits informs both on the causes and the consequences of these changes on ecosystem functioning. [ABSTRACT FROM AUTHOR]

The long-term development of a humic lake ecosystem in Poland was investigated via palaeoecological analyses of age-dated sediment cores. Peat and lacustrine deposit records spanning approximately 12,000 years of lake history were analysed with regard to palynomorphs, plant macrofossils, degree of peat decomposition, Cladocera and geochemistry. Our study demonstrated the difficulty of classifying sediments deposited in humic lakes. We considered it inadequate to classify dy sediment exclusively using macroscopic criteria in the absence of geochemical parameters. Our study of the palaeoecology of the humic lake suggested three primary shifts in its trophic status: from oligotrophy to mesotrophy (Allerød-Boreal), to eutrophy (Atlantic), and to humotrophy (from the Sub-Boreal to the present). The results indicated that shifts in the trophic status occurred in response to climatic changes and factors linked to the catchment. The transformation from a clearwater lake of high trophic status to a humic lake was possible, such that the latter may originate not only from an oligotrophic lake. As a result of our pioneering study, we determined that a humic water body may even develop because of transformation of a eutrophic lake. [ABSTRACT FROM PUBLISHER]

Using a multi-proxy analysis of a postglacial sedimentary sequence from a lowland wetland, we address the possible drivers of change in the wetland habitats and surrounding landscapes of southwestern Slovakia. A 5 m-deep core in the Parížske močiare marshes was investigated for pollen, plant macro-remains, molluscs, organic content and magnetic susceptibility. The palaeoecological record extends from the Pleistocene–Holocene transition (≥11,200 cal. BP) to the 5th millennium cal. BP and was correlated with a macrophysical climate model (MCM) and archaeological data. Our results show the transformation of an open parkland landscape with patches of coniferous forest to a temperate deciduous forest at the onset of the Holocene. The record is remarkable for an early occurrence of Quercus pollen and macro-remains around 11,200 cal. BP and its early expansion (10,390 cal. BP) in the vegetation. Such an early spread of Quercus has not previously been recorded in the region, where Corylus is usually the first to expand among temperate trees. This unusual development of forest communities was most probably triggered by a short-lived increase in precipitation and decrease in temperature, as reconstructed by the MCM model. Higher moisture availability and low temperature inhibited Corylus and favoured the spread of Quercus. Later, the climate became drier and warmer, which, together with fires, supported the expansion of Corylus. Since 7300 cal. BP, human activities became most likely the dominant influence on the landscape. Deforestation contributed to soil erosion, which halted the accumulation of organic material after 5520 cal. BP, followed by the accumulation of clay sediments. [ABSTRACT FROM AUTHOR]

New pollen, phytolith, charcoal and diatom data from 14C AMS-dated sediments from three clusters of former occupation sites on the southern Yangtze Delta – Liangzhu, Majiabang and Chuodun – reveal that hydrological conditions were a key factor influencing early food production on the southern Yangtze Delta. At least two episodes of inundation are recognized, the first occurring at c. 7200–5700 cal. yr BP and a second from c. 4700 cal. yr BP. The first involved increasing salinity of surface waters, likely associated with marine intrusion linked to post-glacial sea-level change (meltwater pulse (MWP) 2). The second appears to have been freshwater in nature and driven at least in part by extreme meteorological events of high levels of precipitation in combination with impeded drainage. These two episodes had profound impacts on Neolithic settlement and farming. Further hydrological changes, presumably linked to changes in sedimentary regime, geomorphology and drainage of the Taihu depression, recorded at the Chuodun site after c. 3000 cal. yr BP, appear to have had a major effect on technologically relatively advanced food production systems. While environmental pressures appear to have played an important role in shaping human activities and settlement on the southern Yangtze Delta, people responded by adopting strategies that included an increased reliance on food production, migration to more clement locations and implementation of new technologies, which possibly included the construction of flood defence works. [ABSTRACT FROM AUTHOR]

Archaeological and historical records suggest that cultivation became established rather late in northern Fennoscandia, preferably in coastal villages of northernmost Sweden during the 14th century. The expansion of these settlements has obliterated the relevant biological archives, thus restricting our ability to conduct palaeoecological studies of the oldest villages and limiting our knowledge of their cultivation history. In a secondary phase, new settlements were established around the periphery of these primary villages. We hypothesize that such secondary villages, which generally are only moderately affected by urban expansion, may function as key sites for vegetation-history studies and that the results can be extrapolated to provide clues about the establishment of primary villages and the initiation of associated permanent cultivations. Analyses of pollen, pollen accumulation rates, charred particles and loss-on-ignition residues from a small lake in the secondary village of Arnemark revealed continuous land use from at least c. 1650 cal. BP (cal. ad 300), a step-up phase in grazing and trampling around 1200 cal. BP (cal. ad 750), and permanent cultivation during the last c. 625 years (cal. ad 1325). The results suggest that the secondary village was established around cal. ad 750, that is, c. 600 years earlier than previously thought and that cultivation here was initiated at the same time as has been suggested for the primary villages by the coast. In this study, we also demonstrate that using pollen from old cereal types as references can make the distinction between cereal and wild-grass pollen more reliable. [ABSTRACT FROM AUTHOR]

The present day distribution of Miombo savanna-woodland in Mozambique has been attributed to an expansion due to the clearing of original coastal forests through agriculture and use of fire. Here, we test this hypothesis using palaeoecological data from Lake Nhauhache, situated in the Vilankulo region. Our analysis shows that Brachystegia, one of the main constituents of the Miombo, has varied over time, and its variability seems to be driven by hydrological changes related to climatic variability rather than by land-use changes. The analyses show that Brachystegia was most common during ad 200–700 when a marshy forest/shrub community was dominant. After ad 700, this community changes to a dominance of Syzygium and Fagara linked to gradually rising water levels. Brachystegia remains in low abundance and fluctuating over time. From ad 1000, a general decline in trees/shrubs in favour of grasses concurs with an increase in grass pollen (possibly cereal) and charcoal, most probably as a result of farming activities. The decline in tree taxa was probably exacerbated by periodic droughts after c.ad 1200 as indicated by the diatom assemblage. In the period ad 1700 to late 1800, arboreal pollen is well represented, and this is concurrent with the diatom record suggesting high lake levels. [ABSTRACT FROM AUTHOR]

Human access to natural resources (or provisioning ecosystem services) is controlled by climate conditions and usage. In the central Andean highlands, around Lake Titicaca, water and woodlands have been critical resources for human populations over the last 5000 years. During this time period, human society developed from mobile hunter–forager groups into settled agrarian populations (c. 3400 years ago) through to the rise of some of the first ‘civilizations’ in the central Andes (c. 2500 years ago). Records of past environmental and vegetation change reveal that coincident with these societal reorganizations were variations in the availability of water and woodland resource. Prior to Hispanic arrival in the central Andes (before ad 1532), changes in availability of natural resources are shown to be concomitant with societal reorganizations; however, changes in societal organization are shown not to necessarily result in the degradation of ecosystem services (i.e. woodland resource available). Through the last 5000 years, three concomitant repeated adaptive cycles of destabilization, reorganization, growth and maxima are identified in human and ecological systems. This suggests that long-term (>100 year) societal development was paced by both increases and decreases in ecosystem service provision. The approach of past societies to dealing with changes in baseline resource availability may provide a useful model for policymakers to consider in the light of the predicted scarcity of resource over the coming decades. [ABSTRACT FROM PUBLISHER]

A palynological reconstruction (n = 25 profiles) suggests that the northern extent of lodgepole pine (Pinus contorta var. latifolia Engelmann ex S. Watson) occurred between 59° and 60°N latitude in northwest North America from 10,000 to 7000 calendar years before present (cal. yr BP) prior to entering Yukon. Although specific migration pathways could not be resolved with the available palynological data, mountains along the southern edge of Yukon appear to have diverted lodgepole pine migration through the Carcross and Frances Lake areas in southwest and southeast Yukon, respectively. Migration in the southwest (70 m/yr) was likely confined to lower elevations of the Yukon and Teslin river valleys, with lodgepole pine reaching 61°N ~2000 cal. yr BP. Along the eastern route, migration was channeled through a 15–20 km wide pass in a 200 km mountainous front. After breaching the Liard drainage divide north of Frances Lake ~4000 cal. yr BP, migration progressed northwest (160–220 m/yr) along the Tintina Trench. Lodgepole pine was estimated to have reached its near present-day northern limit (~63°N) ~1790 cal. yr BP, which is ~1290 years earlier than previously thought. This difference in arrival dates is due the use of a >5% rather than a >15% pine pollen content threshold, which appears to correspond with >1% pine tree cover in the landscape. Climatic cooling after 1000 cal. yr BP that caused a population decline at higher elevations is hypothesized to explain the present-day sparse and disjunct distribution of pine across Yukon north of 61°N. [ABSTRACT FROM AUTHOR]

Lac Moras is a small lake located on a low-elevation plateau in the upper Rhône Valley (304 m a.s.l.). The upper 5 m of accumulated sediment in the lake span 7500 years and offer a detailed record of environmental perturbations and land-use history at a local scale. A multiproxy analysis (pollen, charcoal and geochemical parameters) led to the establishment of four periods of landscape dynamics. The first evidence of human impacts was recorded during the Neolithic and Bronze Age (6000–2700 cal. BP). These impacts were temporary and most likely affected small areas. The second period, in the Iron Age/classical antiquity (2200–1900 cal. BP), appears to be a key period in which the intensification of anthropogenic pressure (primarily grazing with localised areas of cultivation) caused high-intensity erosion events and deeply affected soil stability. During the Middle Ages, wheat, rye and hemp cultures as well as tree farming (walnut, chestnut) were intensively developed. From 50 cal. BP (the 19th century) onward, crop cultivation declined and was gradually replaced by meadows and pastures. According to these transformations in agro-pastoral practices, the associated use of fire changed. Whereas fire was used intensively to clear wild areas from the Neolithic to the early Middle Ages, its use was restricted to cleaning agro-pastoral areas during the second part of the Middle Ages. These periods correspond to the different reconstructed types of land use. These changes correspond to population growth, the evolution of settlement patterns and the increase in agrarian productivity by technological advances. The present landscape is a result of this coupled agrarian and environmental history. It is notable that the first permanent alteration occurred as early as classical antiquity. [ABSTRACT FROM AUTHOR]

Pollen, non-pollen palynomorph, macrofossil, and lithological analyses of mid-Holocene deposits from a small peat bog in northern Poland provide new proxy data on vegetation dynamics and climate between c. 9500 and 4600 cal. BP. The most prominent wetter climate phases occurred between c. 9500 and 9280±160 and between c. 5000 and 4600 cal. BP while a hot and dry period between 8185±145 and 5299±195 cal. BP corresponds with the Holocene Thermal Maximum (HTM). The HTM phase has been characterized by absolute dominance of Tilia cordata and the presence of T. platyphyllos beyond its current geographical range limit and a c. 2700 yr long, high incidence of the parasite fungus Kretzschmaria deusta in the local forest stand, concurrent with a dry phase on the mire. For the HTM, we suggest mean summer temperatures at least 3°C higher than today’s values. These data are in accordance with the geographic pattern of the HTM temperature anomalies in northern Europe, including the Baltic region, which suggest a gradient of positive anomalies from north to south and from west to east. The data also illustrate the effect of climate warming on the mid-Holocene pathogen outbreak and may indicate intensive vegetative reproduction as a Tilia strategy for population survival. Summer drought was probably important for high success of K. deusta in infecting weakened Tilia trees. [ABSTRACT FROM PUBLISHER]

Model validation experiments are fundamental to ensure that the peat growth models correspond with the diversity in nature. We evaluated the Holocene Peatland Model (HPM) simulation against the field observations from a chronosequence of peatlands and peat core data. The ongoing primary peatland formation on the isostatically rising coast of Finland offered us an exceptional opportunity to study the peatland succession along a spatial continuum and to compare it with the past succession revealed by vertical peat sequences. The current vegetation assemblages, from the seashore to a 3000 year old bog, formed a continuum from minerotrophic to ombrotrophic plant communities. A similar sequence of plant communities was found in the palaeovegetation. The distribution of plant functional types was related to peat thickness and water-table depth (WTD) supporting the assumptions in HPM, though there were some differences between the field data and HPM. Palaeobotanical evidence from the oldest site showed a rapid fen–bog transition, indicated by a coincidental decrease in minerotrophic plant functional types and an increase in ombrotrophic plant functional types. The long-term mean rate of carbon (C) accumulation varied from 2 to 34 g C/m2 per yr, being highest in the intermediate age cohorts. Mean nitrogen (N) accumulation varied from 0.1 to 3.9 g N/m2 per yr being highest in the youngest sites. WTD was the deepest in the oldest sites and its variation there was temporally the least but spatially the highest. Evaluation of the HPM simulations against the field observations indicated that HPM reasonably well simulates peatland development, except for very young peatlands. [ABSTRACT FROM AUTHOR]

Over the last 200 years Australia has suffered the greatest rate of mammal species extinction of any continent. This demands extensive biodiversity research, but unfortunately has been hampered by poor documentation of Australia’s native species at the time of European colonization. Late-Holocene fossil mammal assemblages preserved in caves, rockshelters and surface lag deposits from deflated sand dunes can provide a more complete understanding of pre-European ecological conditions than can be developed from our knowledge of present biodiversity. In South Australia, few regions have experienced greater landscape modification and biodiversity loss than Yorke Peninsula. We investigate the composition, richness, evenness and age of two owl accumulations from southeastern and southwestern Yorke Peninsula and contrast them with a surface lag deposit assemblage probably accumulated by humans. We then examine the pre-European biogeography of the fauna recovered. The three assemblages have similar species richness, but differ dramatically in composition and evenness. The biases imposed by differing accumulation agents can explain compositional differences between owl and human assemblages, but not the differences between the respective owl accumulations. We argue that key substrate differences – one area is dominated by sand and the other by calcrete – have favoured distinct vegetation communities that fostered distinctly different mammal assemblages from which raptors accumulated prey. The ecological requirements of the extant mammals appear to be reflected in the fossil assemblages, providing support for the application of uniformitarian principles and confidence in the relevance of late-Holocene fossil assemblages to modern conservation and natural resource management. [ABSTRACT FROM AUTHOR]

The call to adopt a longer-time perspective in order to better understand contemporary and near-future global environments is not new. Nevertheless, there is a growing recognition that evidence from the geologically recent past, in particular the late Quaternary, is essential if we are to understand the profound changes that have taken place in the human relationship with the living world. This progress report reviews how the understanding of environmental dynamics over extended time periods is now incorporated into science dealing with predictions of future climate change by the IPCC consortium, how possible analogues for a warmer future are still vigorously explored and how information on past environments may better inform an understanding of contemporary ecosystem processes and influence the future management of biodiversity in protected areas. [ABSTRACT FROM PUBLISHER]

In the southern Duero Basin of central Spain, there are vast areas of aeolian sand sheets and dune fields. A comprehensive survey of the sand quarries in this area identified a number of palaeosols in sedimentary sequences. The identification and AMS radiocarbon dating of soil charcoal fragments collected in these palaeosols indicate the persistence of Pinus pinaster in this area throughout most of the Holocene. Although potential natural vegetation models have usually considered the Pinus pinaster forests in this inland area of artificial origin, soil charcoal analysis provides firm evidence of a natural origin. Our data fit perfectly with the pattern of Holocene vegetation development for inland areas of Iberia, which are characterised by stability of pine forests throughout the Holocene. Finally, the growing body of palaeobotanical evidence from Iberia (macrofossils and pollen) is contributing to improve our knowledge of P. pinaster ecology, showing that this species has been present in most Iberian regions during the Holocene, where it has inhabited areas characterised by a very diverse set of climatic and soil conditions. [ABSTRACT FROM AUTHOR]

In the light of the currently increasing drought frequency and water scarcity on oceanic islands, it is crucial for the conservation of threatened insular vertebrates to assess how they will be affected. A 4000 yr old fossil assemblage in the Mare Aux Songes (MAS), southwest Mauritius, Mascarene Islands, contains bones of 100 000+ individual vertebrates, dominated by two species of giant tortoises Cylindraspis triserrata and C. inepta, the dodo Raphus cucullatus, and 20 other vertebrate species (Rijsdijk, Hume, Bunnik, Florens, Baider, Shapiro et al. (2009) Mid-Holocene vertebrate bone Concentration-Lagerstätte on oceanic island Mauritius provides a window into the ecosystem of the dodo (Raphus cucullatus). Quaternary Science Reviews 28: 14–24). Nine radiocarbon dates of bones statistically overlap and suggest mass mortality occurred between 4235 and 4100 cal. yr BP. The mortality period coincides with a widely recognized megadrought event. Our multidisciplinary investigations combining geological, paleontological and hydrological evidence suggests the lake was located in a dry coastal setting and had desiccated during this period. Oxygen isotope data from a Uranium-series dated stalagmite from Rodrigues, an island 560 km east of Mauritius, supports this scenario by showing frequently alternating dry and wet periods lasting for decades between 4122 and 2260 cal. yr BP. An extreme drought resulted in falling water-tables at MAS and elsewhere on the island, perhaps deprived these insular vertebrates of fresh water, which led to natural mass mortalities and possibly to extirpations. In spite of these events, all insular species survived until at least the seventeenth century, confirming their resistance to climatic extremes. Despite this, the generally exponential increase of combined human impacts on islands including loss of geodiversity, habitats, and stocks of fresh water, there will be less environmental safe-haven options for insular endemic and native vertebrates during future megadrought conditions; and therefore will be more prone to extinction. [ABSTRACT FROM AUTHOR]

We investigated the interplay between climate and the Holocene ecological development of a small low-Arctic lake and its catchment. The remains of terrestrial and aquatic oribatid mites, plant macrofossils, and other invertebrates in a sediment core from Lake SS16 in west Greenland revealed its palaeoecological history over the last 6950 years. Betula nana immigrated into Dryas fell-field and open grassland around 6600 cal. yr BP and then expanded to dominate dwarf-shrub heath that clothed the catchment for 4800 years. Like other lakes in Greenland, the mesotrophic SS16 became progressively oligotrophic as a consequence of nutrient depletion and reduced runoff from the maturing catchment vegetation. Abrupt declines of Lepidurus arcticus and Daphnia probably reflect the immigration of fish around 6300 cal. yr BP. After c. 2000 cal. yr BP, catchment heathland declined with Neoglacial cooling and reduced precipitation and was replaced by open Dryas grassland vegetation and bare soil. Lake productivity also decreased. The major early-Holocene catchment changes pre-date the aquatic changes, revealing decoupling of ecological responses to climate. In the late Holocene, however, climate change was the predominant driver in both lake and catchment. This multiproxy study shows the valuable contribution made by oribatid mites in the reconstruction of direct processes (e.g. precipitation:evaporation ratio), indirect processes (e.g. nutrient sequestration by maturing tundra vegetation, immigration of taxa), and internal feedbacks (e.g. trophic interactions) that controlled ecosystem development in the past. [ABSTRACT FROM AUTHOR]

We reconstruct the vegetational and fire history of the Colli Euganei and northeastern Po Plain from c. 16 500 cal. BP to the present using AMS-dated sedimentary pollen, microscopic and macroscopic charcoal records. Our study site, Lago della Costa, is the only natural water basin with an undisturbed late-Quaternary sediment accumulation in the northeastern Po Plain. Mixed coniferous-deciduous forests occurred since at latest 14 500 cal. BP. Gradual expansion of e.g. Alnus glutinosa and Carpinus betulus is documented after c. 11 000 cal. BP. A further expansion of Abies alba and Alnus at 9200 cal. BP coincided with a population buildup of these species in the Insubrian region c. 200 km northwest of our site. A further increase of Alnus about 6400 cal. BP was accompanied by an expansion of Castanea sativa and Juglans regia as well as meadow and field plants. This vegetational change was contemporaneous with a huge increase of regional and local fire activity. Our data suggest that fire disturbance favoured strong and moderate re-sprouters, e.g. Alnus, Carpinus and Castanea, whereas fire-sensitive taxa, e.g. Tilia and Abies were disadvantaged. The close link between crops, weeds and fire activity suggests human impact as the main source of changes in Neolithic vegetation and fire regime. To our knowledge these are the oldest palaeobotanical data suggesting the cultivation of Castanea and Juglans in Europe and elsewhere. Our pollen and charcoal records document the subsequent cultivation of Castanea, Juglans, Olea and Cerealia t. during the Bronze Age (4150-2750 cal. BP). Subsequently, intensification of land use continued during the Iron and Roman Age and Medieval times. In contrast with other northern Italian sites vegetation around our site was always rather open with a substantial proportion covered by grassland. We explain this peculiarity of the site by its location near river banks and floodlands. [ABSTRACT FROM AUTHOR]

In order to document climate fluctuations during the late Holocene in Nunavik (in the Québec Arctic), a 182 cm peat core extracted from a polygonal peatland in the Salluit region was subjected to macrofossil and pollen analysis. Peat accumulation began around 4500 cal. BP in the peatland and 2340 cal. BP in the core site following the formation of frost cracks and ice wedges. Four distinct Holocene climatic changes were identified. Between 1910 and 1100 cal. BP, the climate was clement (similar to today's climate), which favoured the growth of several species of Sphagnum (from poorly minerotrophic to ombrotrophic conditions). Colder and drier conditions starting around 1100 cal. BP are evidenced by the disappearance of Sphagnum and aeolian sedimentation. A short return to more clement conditions occurred around 870 cal. BP and lasted until 670 cal. BP. Subsequently, the climate once again became colder and drier, which induced significant aeolian activity. Late-Holocene local vegetation changes recorded in the peat core were probably induced by permafrost degradation and aggradation, associated with regional warming and a subsequent cooling trend. [ABSTRACT FROM AUTHOR]

The Apuseni Natural Park (ANP) in northwestern Romania was founded in 1990 to protect the oldgrowth forests in this region and their high species diversity. We present results from palaeoecological investigation (pollen, micro- and macrocharcoal) of two sedimentary sequences from ANP alongside regional archaeological and historical records to explore (1) the degree to which the present-day vegetation in this part of the reserve is a consequence of past land-use systems and forest management; (2) how this forest differs from what was there prior to human activity; and (3) how the understanding of correlations between historical landuse and vegetation changes is directly relevant for reserve conservation strategies and sustainable management of this reserve. Results indicate that anthropogenic activities had little influence on the forest dynamics prior to 200 bC but became evident thereafter as a consequence of forest burning, seasonal pastoralism and small-scale deforestation. From Ad 1550, anthropogenic activities also included wood clearances for smelting, and over the last 150 years it is apparent that these forests have been industrially exploited and managed. despite this legacy of these past land uses, most of the tree species growing presently in the forests are native. Humans have, however, altered their original relative abundance, leading to a great reduction of Fagus sylvatica and Abies alba, and to less extent of Ulmus, Tilia, Fraxinus excelsior and the enrichment with Picea abies, Betula, Alnus, Pinus and some Quercus, Carpinus betulus, Corlyus avellana. [ABSTRACT FROM AUTHOR]

Following the previous report on this subject, published in 2007, there has been a very substantial increase in publications relevant to landscape ecology and this is illustrated by the growth in citations for articles in the core journal Landscape Ecology over the period 2000-2007. The continuing 'identity crisis' of landscape ecology is described and recent literature in the field is then summarized under the following headings: 'Landscape ecology and climate change research'; 'Alternatives to fragmentation and the patch-based model - the links between pattern and process'; 'Fragmentation research'; 'Methodology and techniques in landscape ecology'; and 'Connectivity and graph theoretical approaches'. The review concludes that landscape ecology now represents one important focus within biogeography, linked to ecological biogeography, and takes its place alongside other key foci, including macroecology, palaeoecology and soil science/pedology. Nevertheless, both physical and human geographers still need to embrace landscape ecology even more enthusiastically than they have up until now. [ABSTRACT FROM AUTHOR]

Palaeoenvironmental data are presented from the site of Garðar (modern Igaliku), the location of the cathedral and the bishop's farm in the Norse Eastern Settlement of Greenland. The latter was founded from c. AD 985 and abandoned some time during the fifteenth century. Inspection of drainage ditches located in close proximity to the settlement ruins revealed inter alia an organic-rich unit containing cultural debris (worked wood, animal bone, stone and charcoal) dated by AMS radiocarbon dates on seeds to the period c. AD 1110-1370. Fossil insect and pollen assemblages contained within the deposit appear representative of natural environments (primarily wet eutrophic meadows) but are mixed with high frequencies of a range of synanthropic insects, including human and animal ectoparasites that could only derive from indoor habitats. This is strongly indicative of the manuring of fields with waste from houses and byres in order to increase yields of hay. Large amounts of hay would have been necessary to provide winter fodder for the bishop's herd of cattle - the largest known in Norse Greenland - and dung from these animals seems likely to have been a significant component of the material used to fertilize the fields. The process of spreading the manure at Garðar was probably integrated with the careful manipulation of water resources across the site, indicated by the presence of a network of irrigation channels and dams in the archaeological record, and comparisons are drawn with similar systems elsewhere in Mediaeval Europe. [ABSTRACT FROM AUTHOR]

Archaeologists have made significant contributions to our understanding of ancient island environments, including the timing and implications of the introduction of non-native animals (pigs, chickens, rats, etc.) by humans. Here, we focus on the historical ecology and biogeography of domestic dogs (Canis familiaris) on California's Channel Islands during the Holocene. Dogs are the only animal known unequivocally to have been introduced by Native Americans to the islands, but relatively little is known about their distribution, antiquity or influence on native island fauna and flora. We identified a minimum of 96 dogs from 42 archaeological sites on six of the eight islands. Dogs were present for at least 6000 years and appear to have increased in abundance through time. Our analysis suggests that dogs, along with humans and island foxes (Urocyon littoralis), would have had an impact on native animals and ecosystems, especially breeding birds and marine mammals. Dogs and island foxes likely competed with one another for food, however, and the impacts of dogs on island ecosystems may have been reduced by the presence of island foxes and the symbiotic relationship between dogs and humans. Dogs have been removed from all but one of the islands today, eliminating one of the few terrestrial carnivores present for most of the Holocene. [ABSTRACT FROM AUTHOR]

The decline of S. austinii Sull. Ex Aust. (formerly S. imbricatum Hornsch. Ex Russ. ssp. austinii Sull. Ex Aust.), in most cases to local extinction, represents one of the most striking vegetation changes on the raised bogs of Britain and Northwest Europe during the last 2000 years. This study uses plant macrofossil, pollen and geochemical analyses to explore the record of human impact and land-use intensification at the S. austinii decline. There is a clear temporal association between anthropogenic woodland clearance, cereal cultivation, soil erosion and contemporary climatic change, with the decline of S. austinii. These findings suggest that S. austinii is sensitive not only to rapid climate changes but also to the aerial deposition of soil dust and/or accompanying pollutants. A modern comparison of atmospherically derived nitrogen (N) loadings with the present presence/absence of S. austinii on 16 raised bogs shows that the species is only present where the loading lies below a critical threshold for N of 10 kg/ha per yr. The palaeoecological record also shows that S. austinii has re-established itself during phases of reduced human activity but in contemporary Europe it is difficult to see this happening in the near future. [ABSTRACT FROM AUTHOR]

The coniferous boreal forest of northeastern North America is characterized by large and severe fire events and dominated by black spruce (Picea mariana), with scattered patches of balsam fir (Abies balsamea), a species otherwise predominant in the more southern mixedwood boreal forests, characterized by smaller and less severe fire events. Because balsam fir is a late-successional species ill-adapted to fire, this study aimed at determining if the scattered balsam-fir patches found in the coniferous forest were relics of a former fire regime characterized by less frequent and/or severe conflagrations. Fire and vegetation history were assessed for a coniferous forest site through analyses of charcoal, pollen and plant macroremains preserved in lake sediments, peat and hydromorphic forest soil. Pollen and macroremains analyses show that black spruce dominated the local vegetation since deglaciation (c. 8000 cal. yr BP). Balsam fir was abundant around the site during the warm and humid summers of the Hypsithermal (between c. 7000 and 3500 cal. yr BP), before gradually declining during the cool and dry Neoglacial, which was characterized by increased fire frequency and severity. Scattered balsam fir patches in the coniferous forest result from the fragmentation of formerly larger populations and are presently in disequilibrium with climate. [ABSTRACT FROM AUTHOR]