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Exposure to extreme temperatures can negatively affect animal reproduction, by disrupting the ability of individuals to produce any offspring (fertility), or the number of offspring produced by fertile individuals (fecundity). This has important ecological consequences, because reproduction is the ultimate measure of population fitness: a reduction in reproductive output lowers the population grow

Recent discoveries of several Mesolithic sites within the Dagsmosse Basin, south-central Sweden, offer an opportunity to study the lifestyle and skillsets of Mesolithic hunter-gatherer-fishers operating in wetland environments. In this paper, we present a combined archaeological and palaeoecological analysis of a Mesolithic fenland environment using Repetitive-Proxy Pollen Analysis (RPPA) of early

Irreversible shifts of large-scale components of the Earth system (so-called ‘tipping elements’) on policy-relevant timescales are a major source of uncertainty for projecting the impacts of future climate change. The high latitudes are particularly vulnerable to positive feedbacks that amplify change through atmosphere-ocean-ice interactions. Unfortunately, the short instrumental record does not

Geological archives record multiple reversals of Earth’s magnetic poles, but the global impacts of these events, if any, remain unclear. Uncertain radiocarbon calibration has limited investigation of the potential effects of the last major magnetic inversion, known as the Laschamps Excursion [41 to 42 thousand years ago (ka)]. We use ancient New Zealand kauri trees (Agathis australis) to develop a

Major low-latitude volcanic eruptions cool Earth’s climate, and can lead to a positive phase of the North Atlantic Oscillation (NAO) during winter. However, the question of the climate and circulation impact of Northern Hemisphere high-latitude eruptions has received less attention. Here we show that, contrary to low-latitude eruptions, the response to high-latitude eruptions can be associated wit

Pollen plays a key role in plant reproductive biology. Despite the long history of research on pollen and pollination, recent advances in pollen-tracking methods and statistical approaches to linking plant phenotype, pollination performance, and reproductive fitness yield a steady flow of exciting new insights. In this introduction to the Special Issue “Pollen as the Link Between Phenotype and Fit

The occurrence of within-population variation in germination behavior and associated traits such as seed size has long fascinated evolutionary ecologists. In annuals, unpredictable environments are known to select for bet-hedging strategies causing variation in dormancy duration and germination strategies. Variation in germination timing and associated traits is also commonly observed in perennial

Tephra horizons are potentially perfect time markers for dating and cross-correlation among diverse Holocene palaeoenvironmental records such as ice cores and marine and terrestrial sequences, but we need to trust their age. Here we present a new age estimate of the Holocene Mjauvotn tephra A using accelerator mass spectrometry C-14 dates from two lakes on the Faroe Islands. With Bayesian age mode

Sediment sequences spanning the last 800 years from two small lakes in the south Swedish uplands were explored for assessment of effects of changing human population, local land-use practices and airborne pollution on lake-ecosystem functioning and resilience. Variations in nutrient cycling and deposition of lithogenic elements were studied, using a multi-proxy stratigraphic approach. Carbon and n

We conducted an interlaboratory comparison between our radiocarbon-related research group at Lund University and the established ETH-Zurich facility to test the quality of the results obtained in Lund and to identify sources of potential background differences and scatter. We did find differences between the 2 laboratories in the contributions of chemical preparation, graphitization, and measureme

Can a climate-triggered export of old contaminants from the soil alter the lead (Pb) contaminant burden of subarctic lakes? To address this question, we reconstructed the pollution history of three high latitude lakes situated in a region where a recent climatic shift has occurred. Dated sediment records were used as archives of past Pb inputs to the lakes, where the difference in the (206)Pb/(207

A pollen diagram from a small peat bog on the island of Tristan da Cunha in the central South Atlantic (37 degrees 05'S, 12 degrees 17'W) is presented. The pollen diagram contains data from both introduced and native plant taxa. The earliest pollen grains from introduced Plantago lanceolata are dated to around AD 1570, and probably represent unintentional introductions of weeds by the earliest Por

Permafrost in peatlands of subarctic Sweden is presently thawing at accelerated rates, which raises questions about the destiny of stored carbon and nutrients and impacts on adjacent freshwater ecosystems. In this study we use peat and lake sediment records from the Stordalen palsa mire in northern Sweden to address the late Holocene (5,000 cal BP-present) development of the mire as well as relate

Dendrochronological analysis was applied to subfossil remains of Scots pine (Pinus sylvestris L.) buried in a South Swedish peat deposit. In combination with peat stratigraphy, this approach was explored for its potential to provide information on the local hydrological and depositional history at the site, forming the basis for a regional palaeohydrological analysis. A 726-year ring-width chronol

An important constraint on the reliability of cosmogenic nuclide exposure dating is the rigorous determination of production rates. We present a new dataset for Be-10 production rate calibration from Mount Billingen, southern Sweden, the site of the final drainage of the Baltic Ice Lake, an event dated to 11,620 +/- 100 cal yr BP. Five samples of flood-scoured bedrock surfaces (58.5 degrees N, 13.

Comparison between growth variability, based on ring-width (RW) analysis, and moisture-sensitive signals in tree-ring carbon and oxygen stable-isotope composition provides increased understanding of how climate and hydrology influenced bog pines (Pinus sylvestris L) at two sites in southern Sweden during the mid- and late Holocene. Tree-ring sequences from two subfossil trees collected at raised b

We used the radiocarbon wiggle-match dating technique to date the varved sediments of Lake Gyltigesjon in southern Sweden with the main aim to construct an accurate chronology covering the period between about 3000 and 2000 cal BP. Wiggle-match dating was applied to bulk sediments to evaluate the possibility of constructing accurate chronologies in the absence of terrestrial plant macrofossils and

Kvidingefältet ligger i nordvästra Skåne på Söderåsens nordöstra sida och avlagringen är ett delta som bildades i en havsvik under deglaciationen av området. Syftet med undersökningen är att göra en arkitektonisk analys av Kvidingedeltats tredimensionella uppbyggnad och att ta reda på hur deltautbyggnaden gått till. Sedimentologiska studier i form av översiktskartering utfördes i åtta av täkternasThe Kvidinge deposit is situated in north-western Scania, southern Sweden. It is a delta formed in a bay during the deglaciation of the area. The purpose of the investigation is to do an architectural analysis of the threedimensional build-up of the Kvidinge deposit and to reconstruct the progradation of the delta. Sedimentary studies have been performed in eight sections and seven logs have been

Long-term records of environmental history at decadal to millennial time-scales enable an assessment of ecosystem variability and responses to past anthropogenic disturbances and are fundamental for the development of environmental management strategies. This study examines the local variability of land-use history in the South Swedish Uplands over the last 200 years based on pollen records from t