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Terrestrial vegetation is a crucial component of the Earth system, and its changes not only represent one of the most distinct aspects of climate change but also exert significant feedback within the climate system by exchanging energy, moisture, and carbon dioxide. To quantitatively and mechanistically study climate-vegetation feedback, numerical vegetation models have been developed on the theor

Amassing the available solar energy over the Sahara desert, through the installation of a large-scale solar farm, would satisfy the world’s current electricity needs. However, such land use changes may affect the global carbon cycle, possibly offsetting mitigation efforts. Here a fully coupled Earth System model EC-Earth was used to investigate the impact of a Saharan solar farm on the terrestrial

1. Co-flowering plant species often interact through shared pollinators, with effects ranging from positive (facilitation) to negative (competition). It remains unclear how this variation relates to variation in floral density, floral trait distinctiveness, and local environmental conditions. We studied the effect of grazer exclusion, a proposed local management strategy, on pollinator-mediated pl

Rättighetsinnehavare ska enligt art. 8.3 i Europaparlamentets och rådets direktiv 2001/29/EG av den 22 maj 2001 om harmonisering av vissa aspekter av upphovsrätt och närstående rättigheter i informationssamhället ha möjlighet att begära ett föreläggande mot en mellanhand vars tjänster utnyttjas av tredje part för att göra intrång. I mål C-314/12 UPC Telekabel har EU-domstolen slagit fast att interArt. 8.3 in Directive 2001/29/EC of the European Parliament and of the Council of 22 May 2001 on the harmonisation of certain aspects of copyright and related rights in the information society decrees that Member States shall ensure that rightholders are in a position to apply for an injunction against intermediaries whose services are used by a third party to infringe a copyright. In case C-314/1

Att hitta rätt taggig tistel Det är mitt i den svenska högsommaren. Det är grönt överallt och även här på så nordliga breddgrader står blommorna i full blom, som färgklickar i allt det gröna. Överallt man tittar ser man insekter av alla dess slag surra omkring bland blommorna. Men hur kommer det sig egentligen att vi har en så stor mångfald av olika växter och insekter? Flugor som älskar tistlarInsects and their host plants constitute a considerable proportion of the diversity on earth, and host shifts hence provide excellent study systems to study the process that drive diversification. In this study, I address what the mechanism to achieve assortative mating is in two host races using different host plants to increase our understanding of how reproductive isolation can arise in the fac

Titel: Konsumenters motivation till att återförsälja kläder. Nivå och kurs: Kandidatuppsats vid institutionen för service management och tjänstevetenskap, Lunds Universitet, Campus Helsingborg. KSMK65 Examensarbete för kandidatexamen, VT2020, 15 HP. Författare: Emelie Olesen Handledare: Malin Andersson Inledning: I takt med att konsumenter konsumerar behöver de också göra sig av med föremål. Secon

The global terrestrial carbon cycle plays a pivotal role in regulating the atmospheric composition of greenhouse gases. It has recently been suggested that the upward trend in net primary production (NPP) seen during the 1980's and 90's has been replaced by a negative trend since 2000 induced by severe droughts mainly on the southern hemisphere. Here we compare results from an individual-based glo

We evaluated the seasonality of CO2 fluxes simulated by nine terrestrial ecosystem models of the TRENDY project against (1) the seasonal cycle of gross primary production (GPP) and net ecosystem exchange (NEE) measured at flux tower sites over different biomes, (2) gridded monthly Model Tree Ensembles-estimated GPP (MTE-GPP) and MTE-NEE obtained by interpolating many flux tower measurements with a

Past, present, and possible future changes in the Baltic Sea acid-base and oxygen balances were studied using different numerical experiments and a catchment-sea model system in several scenarios including business as usual, medium scenario, and the Baltic Sea Action Plan. New CO2 partial pressure data provided guidance for improving the marine biogeochemical model. Continuous CO2 and nutrient mea

It is over three decades since a large terrestrial carbon sink (S-T) was first reported. The magnitude of the net sink is now relatively well known, and its importance for dampening atmospheric CO2 accumulation, and hence climate change, widely recognised. But the contributions of underlying processes are not well defined, particularly the role of emissions from land-use change (E-LUC) versus the

Isoprene emission from Sphagnum species naturally growing at different positions above the water table were measured in a subarctic peatland and at monoliths from a temperate bog. Our objectives were to investigate (1) whether emission rates were species and/or moisture dependent, and (2) whether short-term temperature history had an influence on emission capacity. We expected greater emission cap

Herbivory is an important part of most ecosystems and affects the ecosystems' carbon balance both directly and indirectly. Little is known about herbivory and its impact on the carbon balance in high arctic mire ecosystems. We hypothesized that trampling and grazing by large herbivores influences the vegetation density and composition and thereby also the carbon balance. In 2010, we established fe

We present a network of sites across Fennoscandia for optical sampling of vegetation properties relevant for phenology monitoring and satellite data calibration. The network currently consists of five sites, distributed along an N-S gradient through Sweden and Finland. Two sites are located in coniferous forests, one in a deciduous forest, and two on peatland. The instrumentation consists of dual-

Terrestrial ecosystems currently sequester about one third of anthropogenic CO 2 emissions each year, an important ecosystem service that dampens climate change. The future fate of this net uptake of CO 2 by land based ecosystems is highly uncertain. Most ecosystem models used to predict the future terrestrial carbon cycle share a common architecture, whereby carbon that enters the system as net p

In this paper, a novel method for analysing a bird’s song is presented. The song of male great reed warblers is used for developing and testing the methods. A robust method for detecting syllables is proposed and a classification of those syllables as compared to reference syllables is done. The extraction of classification features are based on the use of singular vectors in different time-freque

The maximum light use efficiency (LUE = gross primary production (GPP)/absorbed photosynthetic photon flux density (aPPFD)) of plant canopies has been reported to vary spatially and some of this variation has previously been attributed to plant species differences. The canopy nitrogen concentration [N] can potentially explain some of this spatial variation. However, the current paradigm of the N-e

The aim of the study was to estimate the range of climate variability during the Ferdynandovian climatostratigraphic unit (MIS 13-15). The studied pollen sequences encompass two interglacials (Ferdynandovian I and II - FI and F II), the glaciation separating them (FI/II), the late glacial of the Sanian I (= Elsterian 1) and the early glacial of the Sanian II (=Elsterian 2) and are correlated with

Treeline encroachments and retractions can provide global-scale feedbacks to the climate system, and treeline dynamics are therefore of great relevance for understanding global climate variability. To assess the accuracy of long-term treeline simulations based on the generalized dynamic vegetation model LPJ-GUESS, we simulate European Arctic treeline dynamics over the past 9000 years and compare t

Holocene summer temperature reconstructions from northern Europe based on sedimentary pollen records suggest an onset of peak summer warmth around 9,000 years ago. However, pollen-based temperature reconstructions are largely driven by changes in the proportions of tree taxa, and thus the early-Holocene warming signal may be delayed due to the geographical disequilibrium between climate and tree p

Carbon assimilation defined as the overall rate of fixation of carbon through the process of photosynthesis is central to the climate change research. The present study compares the two well-known algorithms in satellite based carbon assimilation estimation, the Vegetation Photosynthesis Model (VPM) and the MOD 17A2 GPP Model, over the tropical forest types in India for a period of two years (Sept