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Given the strong coupling between the carbon (C) and nitrogen (N) cycles, there is substantial interest in understanding how N availability affects C cycling in terrestrial ecosystems, especially in ecosystems limited by N. However, most studies in temperate and boreal forests have focused on the effects of N addition on tree growth. By comparison, less is known about the effects of N availability

Background: The European Union's 7th Framework Programme (EU's FP7) project HEALS – Health and Environment-wide Associations based on Large Population Surveys – aims a refinement of the methodology to elucidate the human exposome. Human biomonitoring (HBM) provides a valuable tool for understanding the magnitude of human exposure from all pathways and sources. However, availability of specific bio

Leaf area index (LAI), a measure of canopy density, is a key variable for modelling and understanding primary productivity, and also water use and energy exchange in forest ecosystems. However, LAI varies considerably with phenology and disturbance patterns, so alternative approaches to quantifying stand-level processes should be considered. The carbon isotope composition of soil organic matter (C

We present quantitative reconstructions of regional vegetation cover in north-western Europe, western Europe north of the Alps, and eastern Europe for five time windows in the Holocene [around 6k, 3k, 0.5k, 0.2k, and 0.05k calendar years before present (bp)] at a 1 degrees x1 degrees spatial scale with the objective of producing vegetation descriptions suitable for climate modelling. The REVEALS m

Popular Abstract in Swedish Det görs en rad försök till demokratisk förnyelse ute i kommunerna. I denna avhandling är det min ambition att analysera ett sådant försök; medborgarutskotten i Helsingborg. De frågeställningar avhandlingen behandlar är 1) vad ligger bakom samtalets betoning i medborgarutskottens deltagardemokratiska aktiviteter? 2) Hur positioneras kommuninvånare som medborgare då medThis is a study of civic communication in a municipal setting. In the south Swedish municipality of Helsingborg operated Civic Committees between 2003 and 2006. The Civic Committees organized different kinds of activities together with the citizens out in the different neighbourhoods of the municipality, such as open meetings, neighbourhood walks, workshops for the future and meetings with specifi

Feather mosses utilize various sources of nitrogen (N): they absorb N deposited on leaf tissue, they host N-2 fixing cyanobacteria, and they are able to take up N directly from soil. In addition to their importance as primary producers in boreal ecosystems, feather mosses play a significant role in N cycling. However, estimates of their ability to take up N from soil in situ are scarce. Further, c

Changes in the seasonal timing of life history events are documented effects of climate change. We used a general model to study how dispersal and competitive interactions affect eco-evolutionary responses to changes in the temporal distribution of resources over the season. Specifically, we modeled adaptation of the timing of reproduction and population dynamic responses in two competing populati

Land-use change is a major driver of the global loss of biodiversity, but it is unclear to what extent this also results in a loss of ecological traits. Therefore, a better understanding of how land-use change affects ecological traits is crucial for efforts to sustain functional diversity. To this end we tested whether higher species richness or taxonomic distinctness generally leads to increased

Background: Mechanical ventilatory support seriously affects speaking and communication, and earlier studies show that many ventilator-supported patients experience difficulties and frustration with their speech and voice production. Since there is a growing number of individuals who require mechanical ventilatory support and there is a paucity of studies that examine ventilator-supported communic

Popular Abstract in Swedish Barns villkor i stadsmiljö är ett viktigt tema för förståelsen av den moderna barndomen. Barn har emellertid sällan tillfrågats om sin syn på stadens miljövillkor. Avhandlingens syfte är sammanfattningsvis: * Att beskriva de sakkunnigas försök att skapa goda uppväxtvillkor för barn i stadsmiljö, utifrån det jag sammanfattande benämner "de för barnen tänkta perspektivenChildren's conditions in urban environments are an important theme for understanding modern childhood, yet children have rarely been asked about their views of urban childhood conditions. The aim of the dissertation is: To describe the experts' attempts to create good conditions for growing up in an urban environment. This is summed up as "perspectives thought out for the children". To investiga

Evolutionary molecular studies of island radiations may lead to insights in the role of vicariance, founder events, population size and drift in the processes of population differentiation. We evaluate the degree of population genetic differentiation and fixation of the Canary Islands blue tit subspecies complex using microsatellite markers and aim to get insights in the population history using c

Background: As more people reach older age, there is a growing interest in improving old person's health, activity, independence and social participation, thereby adding quality to the extended years. Preventive home visits (PHV) programs for old people have received much attention in recent decades. A large body of research shows mixed effects, and argues that a home visit is a complex social pro

Introduction Colon cancer is one of the most common forms of cancer world wide, with an incidence of almost 1 million cases anually. Surgery is a prerequisite for cure and the majority of patients are potentially curable at diagnosis. For a surgical resection to be curative the surgeon needs to remove the tumour together with all affected regional lymph nodes. How extensive the mesenteric resecti

Biomass burning is one of the largest sources of atmospheric trace gases and aerosols globally. These emissions have a major impact on the radiative balance of the atmosphere and on air quality, and are thus of significant scientific and societal interest. Several datasets have been developed that quantify those emissions on a global grid and offered to the atmospheric modelling community. However

The Quaternary sedimentary succession in Vendsyssel, northern Denmark, contains a unique, high-resolution record of the last interglacial and glacial periods. There is still much debate, however, about the timing and ice extent in this southwestern part of the Scandinavian Ice Sheet, particularly during the Middle Weichselian. In this study, a detailed lithostratigraphical subdivision is establish

Aims Biogeographical evidence suggests a strong link between climate and patterns of species diversity, and climate change is known to cause range shifts. However, there is little understanding of how shifts affect community composition and we lack empirical evidence of recent impacts of climate change on the diversity of vertebrates. Using a long-term comprehensive dataset on bird abundance, we e

The forest, savanna, and grassland biomes, and the transitions between them, are expected to undergo major changes in the future due to global climate change. Dynamic global vegetation models (DGVMs) are very useful for understanding vegetation dynamics under the present climate, and for predicting its changes under future conditions. However, several DGVMs display high uncertainty in predicting v

It has been shown that vegetation growth in semi-arid regions is important to the global terrestrial CO2 sink, which indicates the strong need for improved understanding and spatially explicit estimates of CO2 uptake (gross primary production; GPP) in semi-arid ecosystems. This study has three aims: (1) to evaluate the MOD17A2H GPP (collection 6) product against GPP based on eddy covariance (EC) f