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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

Popular Abstract in Swedish VIKTEN AV HETEROGENA JORDBRUKSMILJÖER FÖR GRÅSPARVEN Under de senaste 40 åren har vårt odlingslandskap genomgått kraftiga strukturella förändringar som en konsekvens av att jordbruket har intensifierats och effektiviserats. Dessa förändringar har möjliggjort en nödvändig, ökad produktion av spannmål och andra grödor men samtidigt har det haft förödande konsekvenser på dStrong declines of European farmland birds in recent decades are assumed to be caused by decreased food availability resulting from agricultural intensification and concomitant loss of farmland heterogeneity. One of the species suffering particularly strong declines in NW European countries is the house sparrow. In this thesis I investigated the importance of farmland land-use on house sparrow eco

Ongoing work in developing a general structure and a comprehensive components library aiming at modelling liquid-food process lines is presented. The dynamic component models were developed in an object-oriented library structure based on the dynamic modelling language Modelica using the object-oriented graphical tool Dymola. The models were based on fundamental conservation laws and can simulate

Objective. Renal concentrating capacity (RCC) has been used as a tool in the diagnosis of the site of urinary tract infection (UTI). In this study, RCC was measured in women with symptoms of UTI in relation to the clinical picture and the bacterial species isolated. Material and methods. In 633 outpatients aged >= 18 years with symptoms of UTI, a renal concentration test with desmopressin was perf

The environmental footprint of IT products are significant and, in spite of manufacturing and product design improvements, growing consumption of electronics results in increasing absolute environmental impact. Computers have short technological lifespan and a lot of the in-build performance, although necessary, remains idling for most of the time. Today, most of computers used in non-residential

Various transport phenomena in conjunction with chemical reactions are strongly affected by reformer configurations and properties of involved porous catalyst layers. The considered composite duct is relevant for a methane steam reformer and consists of a porous layer for the catalytic chemical reactions, the fuel gas flow duct and solid plate. In this paper, a fully three-dimensional calculation