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In this study we quantify the partitioning of recent assimilates to above- and below-ground carbon (C) pools in two subarctic mire ecosystems - wet minerotrophic and semiwet ombrotrophic mire - using in situ C-14 pulse-labelling. Ecosystem C partitioning to rhizomes, coarse roots, fine roots, dissolved organic carbon (DOC) and microbes were quantified twice during the growing season at three diffe

Methane (CH4) fluxes 1997-2010 were studied by combining remotely sensed normalised difference water index (NDWI) with in situ CH4 fluxes from Rylekaerene, a high-Arctic wet tundra ecosystem in the Zackenberg valley, north-eastern Greenland. In situ CH4 fluxes were measured using the closed-chamber technique. Regression models between in situ CH4 fluxes and environmental variables [soil temperatur

Accumulated carbon uptake, apparent quantum yield (AQY) and light-saturated net CO2 assimilation (A(sat)) were used to assess the responses of photosynthesis to environmental conditions during spring for three consecutive years. Whole-tree chambers were used to expose 40-year-old field-grown Norway spruce trees in northern Sweden to an elevated atmospheric CO2 concentration, [CO2], of 700 mu mol C

Objective To compare drug survival on adalimumab, etanercept and infliximab in patients with rheumatoid arthritis (RA). Methods Patients with RA (n=9139; 76% women; mean age 56 years) starting their first tumour necrosis factor (TNF) inhibitor between 2003 and 2011 were identified in the Swedish Biologics Register (ARTIS). Data were collected through 31 December 2011. Drug survival over up to 5 ye

Resolving challenges related to the sustainability of natural capital and ecosystem services is an urgent issue. No roadmap on reaching sustainability exists; and the kind of sustainable land use required in a world that acknowledges both multiple environmental boundaries and local human well-being presents a quandary. In this commentary, we argue that a new globally consistent and expandable syst

Regional vegetation-climate modelling studies have typically focused on boreal or temperate ecosystems in North America and Europe, almost completely overlooking tropical ecosystems. We present the first results of simulated regional vegetation-climate dynamics in Middle America as simulated by the model, LPJ-GUESS. The Kappa statistic indicated poor agreement, with a Kappa value of 0.301. When we

Arctic ecosystems play a key role in the terrestrial carbon cycle. Our aim was to combine satellite-based normalized difference vegetation index (NDVI) with field measurements of CO2 fluxes to investigate changes in gross primary production (GPP) for the peak growing seasons 1992-2008 in Rylekaerene, a wet tundra ecosystem in the Zackenberg valley, north-eastern Greenland. A method to incorporate

Palsa mires, nutrient poor permafrost peatlands common in subarctic regions, store a significant amount of carbon (C) and it has been hypothesized their net ecosystem C balance (NECB) is sensitive to climate change. Over two years we measured the NECB for Stordalen palsa mire and found it to accumulate 46 g C m(-2) yr(-1). While Stordalen NECB is comparable to nutrient poor peatlands without perma

Here we present results from a field experiment in an Arctic wetland situated in Zackenberg, NE Greenland. During one growing season we investigated how dominance of the sedge Eriophorum scheuchzeri affected the below-ground concentrations of low molecular weight carbon compounds (LMWOC) and the fluxes of CO2 and CH4 in comparison to dominance of other sedges (Carex stans and Dupontia psilosantha)

Remote sensing (RS) time series are an excellent operative source for information about the land surface across several scales and different levels of landscape heterogeneity. Ustin and Gamon (2010) proposed the new concept of "optical types" (OT), meaning "optically distinguishable functional types", as a way to better understand remote sensing signals related to the actual functional behavior of

Background: The metabolic syndrome describes a cluster of cardiovascular risk factors that frequently appear together. Its diagnosis is generally based on several well-recognized indicators in clinical practice, such as abdominal obesity, elevated triglycerides, reduced high-density lipoprotein, raised blood pressure, and elevated fasting plasma glucose. Today, decisive importance must be attached

One major challenge to the improvement of regional climate scenarios for the northern high latitudes is to understand land surface feedbacks associated with vegetation shifts and ecosystem biogeochemical cycling. We employed a customized, Arctic version of the individual-based dynamic vegetation model LPJ-GUESS to simulate the dynamics of upland and wetland ecosystems under a regional climate mode

Surging outlet glaciers are important in draining large ice caps, but the mechanisms controlling surge periodicities are poorly known. We investigated a sediment sequence from the glacier-fed Lake Logurinn in eastern Iceland, and our unique annually resolved data, based on sedimentary varves, imply that Eyjabakkajokull, an outlet glacier of Vatnajokull, began surging about 2200 cal a BP (before 19

The associations between floristic and palynological richness and landscape structure were studied based on modern pollen-vegetation data from a patchy cultural landscape in southern Estonia (northern temperate vegetation zone). Nine study sites (small lakes and their surrounding vegetation) represent land cover gradient from closed forest to semi-open vegetation. Floristic richness (number of spe

High and low pollen deposition years in the period 1998-2010 were recorded for ten forest-forming trees in Roztocze (SE Poland) using Tauber-style traps. The coincidence of very high/low pollen deposition years recorded in Tauber traps and aerobiological data obtained by volumetric samplers shows that these phenomena occur simultaneously in different places across vast areas of a tree's distributi

Background: Topical negative pressure (TNP), widely used in wound therapy, is known to stimulate wound edge blood flow, granulation tissue formation, angiogenesis, and revascularization. We have previously shown that application of a TNP of -50 mmHg to the myocardium significantly increases microvascular blood flow in the underlying tissue. We have also shown that a myocardial TNP levels between -

This dissertation aims to contribute empirically and theoretically, to the field of Islamology and Religious Studies in general. It does so by investigating the possible relation between Israeli Muslim women’s choice of religious identification and their individual experiences in everyday life transitions. Many of these women are traveling daily from their hometowns or villages to the major cities

Light sensors are increasingly used to monitor vegetation growing status by measuring reflectance or transmittance in multispectral or photosynthetically active radiation (PAR) bands. The measurements are then used to estimate vegetation indices or the fraction of absorbed PAR (FPAR) in a continuous and long-term manner and to serve as inputs to environmental monitoring and calibration/validation

Climate warming in the Swedish sub-Arctic since 2000 has reached a level at which statistical analysis shows for the first time that current warming has exceeded that in the late 1930' s and early 1940' s, and has significantly crossed the 0 degrees C mean annual temperature threshold which causes many cryospheric and ecological impacts. The accelerating temperature increase trend has driven simil