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Popular Abstract in Chinese 北极和亚北极地区对全球气候变化影响尤为重要。目前，北极地区正面临着变暖速度高于全球平均的现状。全球大约有50%的土壤碳储存在高纬度地区的土壤里，这些土壤碳主要分布于冻土层和泥炭层中。冻土层的解冻会使原先被冻结的土壤碳加速分解，产生温室气体，从而对全球变暖形成一个强烈的正反馈。与此同时，气温的增加可能会很大程度地影响植被在这些地区的生长和分布。动态生态系统模型是一种非常强大的工具，被用来研究气候变化对生态系统的影响，并且可以量化生态系统对大气的反馈信息。然而这些模型通常只关注大气、地表植被和土壤之间的水和碳的纵向转移，从而忽略了其在模型空间单元中的横向移动。这样可能会导致模型对于水和碳平衡的计算不够准确和全面，尤其在气候敏感的高纬度极地地区，这种偏差可能会更大。 本论文旨在解决动态生态系统模型中的这个局限性问题。基于目前最先进的动态生态The Arctic and Subarctic regions are of particular importance to the global climate change and are now experiencing a climate warming that is higher than the global average. Around 50% of the global soil carbon is stored in high latitude soils, especially in permafrost and peatland soils. Permafrost thawing, speeding up the decomposition of previously frozen soil carbon, is expected to result in s

An extract of a culture of the fungus Galiella rufa yielded several new derivatives of pregaliellalactone (1) that were characterised by NMR and MS experiments. The tetraene 4 has been reported previously, but was in this investigation isolated in sufficient amounts for the determination of the configuration of the C-4/C-5 double bond which is Z, not E. The possibility that any of the new compound

Inland waters were recently recognized to be important sources of methane (CH4 ) and carbon dioxide (CO2 ) to the atmosphere, and including inland water emissions in large scale greenhouse gas (GHG) budgets may potentially offset the estimated carbon sink in many areas. However, the lack of GHG flux measurements and well-defined inland water areas for extrapolation, make the magnitude of the poten

A repeated pattern of background colour matching in animals is an indication that pigmentation may be cryptic. Here, we examine the relationship between pigmentation of the freshwater isopod Asellus aquaticus and background darkness in 29 lakes, wetlands and ponds in Southern Sweden. The results show that Asellus pigmentation was correlated with substrate darkness across all localities. In seven l

The use of celestial or geomagnetic orientation cues can lead migratory birds along different migration routes during the migratory journeys, e.g. great circle routes (approximate), geographic or magnetic loxodromes. Orientation cage experiments have indicated that migrating birds are capable of detecting magnetic compass information at high northern latitudes even at very steep angles of inclinat

Polymorphisms in genes that encode for metabolic enzymes have been associated with variations in enzyme activity between individuals. Such variations could be associated with differences in individual exposure to carcinogens that are metabolized by these genes. In this study, we examine the association between polymorphisms in several metabolic genes and the consumption of tobacco in a large sampl

Prevotella bivia has been associated with female upper genital tract infections and an increased risk of preterm delivery. In this study, the adherence and invasion capacity of P. bivia was investigated using a cervix epithelial cell line. P. bivia was furthermore analysed for its ability to evoke a proinflammatory cytokine response in epithelial cells. The invasion capacity, defined as the number

The possibility of improving an existing method, based on supercritical-fluid extraction (SFE) and microwave-assisted extraction (MAE), for the determination of banned azo dyes in leather has been studied. Thus, optimization of experimental conditions in different steps (degreasing, reduction, and extraction) of the analytical procedure was performed. The influence of different variables (reaction

Species of Haemoproteus (Haemosporida: Haemoproteidae), avian haemosporidians, have traditionally been described based on morphology of their gametocytes and on limited experimental information on their vertebrate host specificity. We investigated to what extent the morphological species are represented by monophyletic groups based on DNA sequence data using 2 different fragment lengths of the cyt

The kinetics of structure change when dispersions of two different types of lipid-based liquid-crystalline phases, one lamellar and one reversed, are mixed has been investigated using synchrotron small-angle X-ray diffraction and ellipsometry. The systems studied were (i) cubic-phase nanoparticles (CPNPs) based on glycerol monooleate (GMO) stabilized with a nonionic block copolymer, Pluronic F-127

The effect of naturally found densities of the exotic and herbivorous golden apple snail (Pomacea canaliculata) on three dominant aquatic plants - duckweed (Lemna minor), water hyacinth (Eichhornia crassipes) and morning glory (Ipomoea aquatica) - was assessed in a wetland survey and quantified in a field experiment in Laos in southeast Asia. Snail grazing reduced plant biomass, but plant species

The objective of this study was to characterise anaerobic batch biodegradation of potato waste alone and when co-digested with sugar beet leaves. The effects of increasing concentration of potato waste expressed as percentage of total solids (TS) and the initial inoculum-to-substrate ratio (ISR) on methane yield and productivity were investigated. The ISRs studied were in the range 9.0-0.25 and in

Previous studies of high-risk breast cancer families have proposed that two major breast cancer-susceptibility genes, BRCA1 and BRCA2, may account for at least two-thirds of all hereditary breast cancer. We have screened index cases from 106 Scandinavian (mainly southern Swedish) breast cancer and breast-ovarian cancer families for germ-line mutations in all coding exons of the BRCA1 and BRCA2 gen

The relationships and the zoogeography of the three extant pinniped families, Otariidae (sea lions and fur seals), Odobenidae (one extant species, the walrus), and Phocidae (true seals), have been contentious. Here, we address these topics in a molecular study that includes all extant species of true seals and sea lions, four fur seals and the walrus. Contrary to prevailing morphological views the

The aim was to explore the use of an activity-based approach to determine the validity of a set of housing standards addressing accessibility. This included examination of the frequency and the extent of accessibility problems among older people with physical functional limitations who used no mobility device (n = 10) or who used a wheelchair (n = 10) or a rollator (n = 10). The setting was a kitc