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We aim to provide a long-term ecological analysis of land-use and floristic diversity in the transition from traditional to modern land-use management in the time a.d. 1800-2008 in southern Sweden. We use the Regional Estimates of Vegetation Abundance from Large Sites (REVEALS) model to quantify land-cover changes on a regional scale at 20-year intervals, based on the fossil pollen record. Florist

Sedimentary records of invertebrate assemblages were obtained from a small lake in the Khibiny Mountains, Kola Peninsula. Together with a quantitative chironomid-based reconstruction of mean July air temperature, these data provide evidence of Holocene climate variability in the western sector of the Russian Subarctic. The results suggest that the amplitude of climate change was more pronounced in

A late Holocene diatom stratigraphy of Bottom Pond (37050S, 12 70W) was studied and interpreted to infer paleolimnological and climate changes on Tristan da Cunha, South Atlantic. The diatom flora of Bottom Pond is dominated by meroplanktonic Aulacoseira alpigena and A. distans and a benthic/epiphytic flora including Achnanthes spp., Naviculadicta spp., Eunotia taxa and Frustulia rhomboides. The f

For model-based quantitative reconstructions of past vegetation cover on the scale of landscapes, pollen productivity estimates (PPEs) are key input parameters. In this study, we employed a random sampling strategy to collect moss polsters at 20 sites in Changbai Mountain, northeastern China. A detailed vegetation survey within 1000-m radius around each sampling point was carried out and digitized

In February 2009, ST‐Ericsson was formed as a joint venture bringing Ericsson Mobile Platforms and ST‐NXP Wireless together, creating an industry leader in development and design of wireless semiconductor components and platforms. The new company became one of the top players in wireless semiconductors. During the integration, purchasing of indirect material at ST‐Ericsson was outsourced to an out

En datorimplementerad affärsmetod kan se ut på en mängd olika sätt. Beroende på dess utformning och syfte så varierar också de skyddsmöjligheter som står till buds. Både skydd genom patent och som en företagshemlighet erbjuder fördelar som bör tas i beaktande när ett företag sätter upp en strategi för skydd av en affärsmetod. Trots det formella undantaget av affärsmetoder från det patenterbara oA computer implemented business method may take various forms. The protection possibilities may depend on the business method’s character and purpose. Both patent protection and protection as a trade secret provides for advantages as well as disadvantages for a business to consider when choosing a strategy for the protection of a business method. Despite the official exemption of business methods

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

Our paper about the impacts of the Laschamps Geomagnetic Excursion 42,000 years ago has provoked considerable scientific and public interest, particularly in the so-called Adams Event associated with the initial transition of the magnetic poles. Although we welcome the opportunity to discuss our new ideas, Hawks’ assertions of misrepresentation are especially disappointing given his limited examin

The relationship between land-use and floristic diversity in the landscape, for the last millennia, is analysed from two small lakes in southern Sweden. Pollen analysis and the Local Vegetation Estimates (LOVE) model are used to quantify land-cover at local scales with 100-year time windows. Floristic richness is estimated using palynological richness, and we introduce LOVE-based evenness as a pro

We test the hypothesis that rich occurrences of diatoms observed at transitions between major peat units representing different vegetation communities in a peat sequence from subarctic northern Sweden reflect responses to acid deposition from the Samalas AD 1257 and Laki AD 1783/1784 eruptions. We observe sudden changes in the mire ecosystem and thereby in the trophic status and biogeochemical cyc

Sediments from the small lake Ilsø situated in the Illerup/Alken Enge Valley were studied in order to investigate past landscape development at the time of a probably ritual human mass burial following battle during the Roman Iron Age (ad 1–400). A pollen record from Ilsø and a number of other records from Jutland were combined using the Landscape Reconstruction Algorithm to reconstruct local vege

Here we report a new quantitative mean July temperature reconstruction using non-biting midges (chironomids) from the Danish Last Interglacial (LIG) site Hollerup (spanning 127-116 ka). We find that peak mean July temperatures of 17.5 °C, similar to those of the present day (1961-1990 CE), were reached shortly before the onset of the regional Carpinus pollen zone. Through comparison to terrestrial

During and after deglaciation, Lake Vättern developed from a proglacial lake situated at the westernmost rim of the Baltic Ice Lake (BIL), into a brackish water body connecting the North Sea and the Baltic Sea, and finally into an isolated freshwater lake. Here we present geochemical and mineralogical data from a 70-m composite sediment core recovered in southern Lake Vättern. Together with a radi

Over the past 3.5 million years, there have been several intervals when climate conditions were warmer than during the pre-industrial Holocene. Although past intervals of warming were forced differently than future anthropogenic change, such periods can provide insights into potential future climate impacts and ecosystem feedbacks, especially over centennial-to-millennial timescales that are often

This article provides a review of the application of stomatal frequency analysis to fossil leaves in the reconstruction of past atmospheric CO2 concentrations. It presents the physiological basis of the method, an overview of its application to leaves of Quaternary age, and an assessment of its potential and limitations. It also includes a description of the successive stages in a stomatal frequen

The annual 14C data in tree rings is an outstanding proxy for uncovering extreme solar energetic particle (SEP) events in the past. Signatures of extreme SEP events have been reported in 774/775 CE, 992/993 CE, and ∼660 BCE. Here, we report another rapid increase of 14C concentration in tree rings from California, Switzerland, and Finland around 5410 BCE. These 14C data series show a significant i

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

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