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Recently a considerable amount of effort has been put into quantifying how interactions of the carbon and nitrogen cycle affect future terrestrial carbon sinks. Dynamic vegetation models, representing the nitrogen cycle with varying degree of complexity, have shown diverging constraints of nitrogen dynamics on future carbon sequestration. In this study, we use LPJ-GUESS, a dynamic vegetation model

There is compelling new evidence that semi-arid ecosystems are playing a pivotal role in the inter-annual variability and greening trend of the global carbon cycle (Ahlström et al., 2015). The situation is exemplified by the vast inland region of Australia, the driest inhabited continent. Using a global model, Poulter et al. (2014) inferred that Australian ecosystems contributed 57% of a record gl

Uppsatsen behandlar lagen (2017:310) om framtidsfullmakter, dess bakgrund, innehåll och verkningar. Institutet framtidsfullmakt är tänkt att stärka den enskildes möjligheter att styra över sin framtid i fall av försämrad mental kapacitet. Upprättandet av en framtidsfullmakt ska ske då den enskilde har beslutskompetens men träder i kraft först efter att denna kapacitet har gått förlorad till följd This thesis revolves around the law (2017: 310) on continuing powers of attorney; its background, content and effects. The continuing power of attorney is intended to strengthen an individual's ability to control their future in cases of impaired mental capacity. In order to establish a continuing power of attorney, the individual must hold a decision-making competence. However, the act only c

Digitaliseringen har inte bara revolutionerat vår vardag och hur vi kommunicerar utan även skapat en ny arena för brottslighet. Bland de mest bekymmersamma brotten som har ökat i takt med den digitala utvecklingen är sexuella övergrepp mot barn. I syfte bekämpa och förebygga dessa brott presenterade EU-kommissionen 2022 ett förslag till en förordning som ålägger leverantörer av interpersonella komDigitalization has not only revolutionized our daily lives and how we communicate but has also created a new arena for criminal activity. Among the most concerning crimes that have increased with the rise of digital development is child sexual abuse. In order to combat and prevent these crimes, the European Commission presented a proposal for a regulation in 2022 that obliges providers of interper

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 propose and demonstrate a new approach for the simulation of woody ecosystem stand dynamics, demography, and disturbance-mediated heterogeneity suitable for continental to global applications and designed for coupling to the terrestrial ecosystem component of any earth system model. The approach is encoded in a model called Populations-Order-Physiology (POP). We demonstrate the behavior and per

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

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

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

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-

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

Popular Abstract in Swedish Under sin livstid har Jorden genomlevt upprepade naturliga klimatförändringar. Genom att undersöka dessa klimatförändringar över tid och rum så kan vi öka vår förståelse för underliggande dynamik och mekanismer och därmed bättre förstå klimatsystemet. Två grundläggande förutsättningar för sådana undersökningar är trovärdiga rekonstruktioner av tidigare variationer i styThroughout its history Earth experienced a variety of natural climate changes. By investigating their spatial and temporal evolution we can increase the understanding of the mechanisms and dynamics underlying natural climate change and improve our general comprehension of the climate system. Prerequisites of these investigations are reliable reconstructions of past forcing variations as well as so