Background: Eutrophication is a wide spread problem all over the world, this is due to enrichment of surplus nutrients entering water ecosystems. The high concentration of nutrients come from different sources like rural activities, industrial areas and other human activities. This can lead to a high nutrient load entering seas and lakes in the nature. Tributaries can contribute with nutrient loading to main rivers, a tributary like that is Kistingebäcken. Aim: The aim is to investigate how big the nutrient concentration and loading of phosphorus and nitrogen Kistingebäcken contributes to Trönningeån. It will also be investigated if there are any main point source emission of phosphorus and nitrogen from the industrial area located along Kistingebäcken. Method: Water samples were collected in a tributary called Kistingebäcken and in the main river Trönningeån located in the county of Halland, Sweden. These were analyzed to see how much nitrogen and phosphorus they contained. The definition of nutrient concentration is the nutrient level present in an area of a river, while the definition of nutrient load is the quantity of flowing nutrients trough a river which eventually enters lakes, rivers or the sea. Results: There was no significant difference in the total nitrogen concentration between sample point 6 (before the tributary) and sample point 7 (after the tributary) (P=0.904).  There was no significant difference in the total phosphorus concentration between sample point 6 (before the tributary) and sample point 7 (after the tributary) (P=0.743). The nutrient load from sample point 5 contributed with 17-26 kg N/day (11-14%) and 0.29-0.32 kg P/day (13-23%) to Trönningeån. The difference in nutrient load between sample point 6 and 7 was 48-61kg N/day (27-40%) and 0.16-0.5 kg P/day (11-23%). Tukey post hoc test showed that sample point 1 had significantly higher nitrogen concentration in comparison to sample point 2, 3, 4 and 5 (P= 0.001, P<0.001, P<0.001 and P<0.001). Sample point 2 had higher phosphorus concentrations in comparison to sample point 1, 3, 4 and 5 (P= 0.033, P<0.001, P=0.001 and P<0.001). Conclusion: Nitrogen and phosphorus do not increase in concentration after the tributary (sample point 7) in Trönningeån. However, the total nitrogen and phosphorus load increased between 27-40% and 11-23% in Trönningeån after the tributary. Sample point 1 and 2 had the highest nitrogen and phosphorus concentrations and are the main point source emissions in Kistingebäcken, probably due to the landfill facility.

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Understanding sex-specific genetic variance for fitness is of fundamental importance to our understanding of evolution. This thesis presents the findings of empirical investigations into sex-specific genetic variance in fitness. The findings are discussed in terms of their implications for our understanding of the classic evolutionary paradoxes of what maintains genetic variance in fitness and what maintains sexual reproduction, as well as more specific implications regarding adaptation and population viability. Males and females reproduce and accrue fitness in fundamentally different ways, which inevitably comes at a detriment to the fitness of individuals of the opposite sex. This is known as sexual conflict, and because males and females use largely the same genome to develop, grow and reproduce, a genetic tug-of-war ensues. Alternative alleles at sexually antagonistic (SA) genes have opposing fitness effects in males and females. The consequence of this genetic tug-of-war is that alternative allelic variants at SA loci can be maintained in the population. Such SA genetic variation can therefore maintain genetic variance for fitness. Variance in fitness can also be maintained by a constant influx of mutations with weakly deleterious effects and weak selection against them, in what is referred to as mutation-selection balance. Because the average deleterious mutation will be detrimental to both sexes, this source of genetic variance in fitness will have predominantly sexually concordant (SC) effects. This thesis uses a wild-caught population of the seed beetle Callosobruchus maculatus to investigate these two mechanisms of maintaining genetic variance in fitness, as well as the consequences they bear on adaptation, population viability, and the maintenance of sexual reproduction. Results largely support much of the theoretical expectations for sexual conflict, sexual selection and maintenance of genetic variance in fitness, as well as stimulate new thoughts and hypotheses about the nature of SA genetic variation and its interaction with weakly deleterious partially recessive mutations. / Vår kunskap om könsspecifik selektion och genetisk variation för fitness är central för förståelsen av evolutionära processer. I den här avhandligen presenteras resultaten av empiriska undersökningar av just könsspecifik genetisk variation för fitness. Resultaten diskuteras med fokus på deras betydelse för de klassiska evolutionära paradoxerna angående vad som bibehåller genetisk variation i fitness och varför organismer som förökar sig sexuellt är så vanliga, men även mer specifika konsekvenser för en populations anpassningsförmåga och livskraftighet avhandlas. Evolutionen har ofta gynnat olika reproduktiva strategier hos hannar och honor, och dessa strategier kan medföra kostnader för det motsatta könet. Den könskonflikt som uppstår på grund av detta kan också inbegripa en genetisk dragkamp eftersom könen delar genetisk arvsmassa men gynnas av olika anpassningar. Konsekvensen är att alternativa varianter av gener gynnas hos honor och hanar, vilket resulterar i en form av balanserande selektion som kan bibehålla genetisk variation i en population. Genetisk variation i fitness kan även upprätthållas genom en jämvikt mellan ett konstant inflöde av genetisk variation via mutationer med svagt negativ effekt och svag selektion mot dessa mutationer.  Eftersom en negativ mutation normalt kommer vara skadlig för båda könen kommer den här typen av källa till genetisk variation i fitness ha liknande effekt hos könen.  I arbetet med denna avhandlig har jag använt en vilt infångad population av fröbaggaen Callosobruchus maculatus för att undersöka dessa två underliggande mekanismer bakom upprätthållandet av genetisk variation för fitness, samt vilka potentiella konsekvenser de kan ha för en populations anpassningsförmåga och för bibehållandet av sexuell reproduktion. Resultaten i denna avhandling stödjer i stort många av de antaganden som ligger till grund för teorin om könskonflikter, sexuell selektion och vad som upprätthåller genetisk variation för fitness. Resultaten ger också upphov till nya idéer och hypoteser angående  genetisk variation med könsspecifika effekter och dess interaktion med partiellt recessiva negativa mutationer. / <p>The alternative abstract I uploaded should be used as the Swedish summary.</p>

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This work presents new theoretical developments of atomistic spin simulations of magnetic materials at finite temperatures. Special focus is put on the description of longitudinal magnetic fluctuations and the application in random transition metal alloys. A new computational scheme is proposed for mapping total energies from electronic structure calculations to an extended atomistic spin model. The proposed model has some new appealing features from previous models. To be more specific, the proposed model successfully eliminates the reference state dependency of the mapping that previous models have suffered from. Moreover, the proposed model includes longitudinal magnetic fluctuations that gives an improved description of the magnetic properties over a larger temperature interval. The proposed model strives to find the right compromise between accuracy and computational feasibility and it is applied not only to the elemental systems Fe, Co and Ni, but also to a number of binary transition metal alloys such as Permalloy (Fe$_{20\%}$Ni$_{80\%}$) and Fe-Co systems. Electronic structure calculations of Gilbert damping and the closely related magnetodynamic properties, the saturation magnetization and exchange stiffness, have been conducted for a number of different magnetic systems including Permalloy with additional doping of $4d$ or $5d$ transition metal impurities and the full Heusler alloy Co$_2$FeAl. Regarding the Permalloy based systems, a systematic study of the magnetodynamic properties was performed and compared with existing experimental data. In general we found good agreement and manage to explain the main trends regarding the Gilbert damping across the series with a simple model that captures the most important material properties to the damping, namely the spin orbit coupling and density of states at the Fermi level. In Co$_2$FeAl, we calculated the Gilbert damping in different existing crystal structures and compare those with new experimental data and found good agreement between them. Magnon properties of random alloys, like Permalloy, are studied using two complementory methods, the adiabatic magnon spectra valid at zero temperature and from finite temperature atomistic spin dynamics through the dynamical structure factor. The influence of chemical disorder and temperature effects on the magnon properties are investigated that hopefully could motivate new experimental studies of these materials. / <p>QC 20170904</p>

The greenhouse effect is cruical to life on earth. An abnormal increase of the greenhouseeffect, as seen over the last hundred years, because of human activity. Activities such astransports, industry, energy production have a big part in this. The rapid global warming isnow seen as a threat for our society and now, companies can work with their environmental‘’liabilities’’ in many ways. One of them is to work with climate reporting as a tool forreducing greenhouse gas emissions. The purpose of this study is to see what motivatescompanies to work with climate reporting. A qualitative method by using semistructuredinterviews with companies was used in this study. Our results show that a few companiesthink that in addition to the positive aspects that comes with climate reporting, it is costly andhard to work with this tool at times. Climate reporting gives companies a good way ofcommunicating with customers about the sustainability efforts that are being made. This toolalso provides companies with prerequisites for improvement measures. The conclusion is thata company’s climate reporting can contribute in many different ways depending on thecompany’s occupation. Better marketing can be done to increase awareness of this tool forclimate reporting among companies.

The Earth's temperature is predicted to increase by 3-5 °C, the warmer climate is expected to have major effects on aquatic ectotherms. Water temperature is an important environmental factor as it has indirect and direct effects on morphological traits and behaviour of salmonid fishes. Studies have shown that salmon whose eggs have been incubated at higher water temperatures grow faster and have lower metabolic rates than those incubated in colder water temperatures. Metabolic rates and changes in growth may affect behaviour such as dominance and aggression. Salmon that had been incubated in natural temperatures (cold) and elevated temperatures (warm) were studied to investigate if there were any differences in aggression and dominance between treatment groups. The results showed that there was no significant difference between individuals experiencing different temperature treatments during embryogenesis in terms of dominance and aggressive behaviours. However, temperature during embryogenesis may impact other types of behaviour and characteristics of salmonids. Since previous studies have shown that a lower metabolic rate affects fish behaviour, other factors may have a greater influence on temperature. / Då ett varmare klimat förutspås att öka jordens temperatur med 3–5 °C kommer det ha stora effekter hos vattenlevande ektotermer. Vattentemperaturen är en viktig miljöfaktor då den påverkar indirekta och direkta fysiologiska egenskaper hos laxfiskar, som morfologiska egenskaper och beteenden. Studier har visat att lax vars ägg som har inkuberats i högre vattentemperaturer växer snabbare och har en lägre ämnesomsättning än fiskar vars ägg inkuberats vid lägre vattentemperaturer. Ämnesomsättningen och förändringar i tillväxt har visats påverka beteenden som dominans och aggression. Laxfiskar som inkuberats i naturliga temperaturer och förhöjda temperaturer studerades för att undersöka om det fanns några skillnader i aggression och dominans. Resultatet visade att ingen signifikant skillnad fanns i beteende som aggression och dominans mellan individer från de olika temperaturbehandlingarna. Det är dock möjligt att vattentemperatur under embryogenes kan påverka andra beteenden och egenskaper hos laxfiskar. Då tidigare studier har visat att en lägre ämnesomsättning påverkar fiskens beteenden, är det möjligt att andra faktorer kan ha en större påverkan av vattentemperatur.

Most of the world’s ecosystems suffer from stress caused by human activities such as habitat destruction, fragmentation, overexploitation of species and climate change. These factors affect the reproduction and/or survival of individual species as well as interactions between species in ecological communities. Forthcoming effects of this are altered abundances, direct species loss, and indirect cascading extinctions, with yet largely unknown consequences on community structure and functioning. Today, biodiversity loss is of global concern since human society and welfare depend upon resources and services provided by ecosystems. The importance of considering entire ecological communities as a target for conservation and management has been increasingly recognized due to the interdependencie  of species. Our ability to make predictions of the response of ecological communities to stress and biodiversity loss is in need of a deeper understanding of how structure and dynamical processes contributes to the functioning and stability of a community. In this thesis I use mathematical theory and dynamical models to study the response of community structure and resilience to a variety of disturbances affecting species and species interactions, ranging from small perturbations (Papers I-II) to large perturbations (species extinctions, Papers IIIIV). In Paper I we develop Community Sensitivity Analysis (CSA) as an analytical tool to study how a small permanent perturbation to the intrinsic growth rate, or mortality rate, of species is expected to affect i) the resilience (return rate) and ii) the structure (distribution of species equilibrium abundances) of an ecological community. Species interactions are described using Lotka-Volterra predator-prey dynamics. We apply CSA on the pelagic food webs of Lake Vättern and the Baltic Sea, respectively, and find that a change in the mortality rate of large-bodied species has a higher impact on community resilience and structure, compared to a perturbation to small-bodied species. However, analyzing the effect of a proportional change to the growth or mortality rate of species (elasticity analysis) shows that smallbodied species have proportionally larger effects on species equilibrium abundances, but not on resilience. CSA can also be used to study the effect of permanent (absolute or proportional) changes to inter- and intraspecific interaction strengths. For the two pelagic systems used in this study, CSA reveal that changes in the effect of a prey on its consumer tend to affect community structure and resilience significantly more than changes in the effect of a predator on its prey. In Paper II we assess the importance of rare species for the structure and resilience of ecological communities. First we show analytically, for a two species predator-prey system, that a change in the intrinsic growth rate of the rare species affect resilience more than a change in the growth rate of the common species. To test the generality of these results we next apply CSA on complex model food webs. In the analysis we distinguish between four trophic groups, each including only species with a similar trophic position, to separate the effect of abundance from the trophic position of species. Using mixed effect models we find support for our analytical predictions. More precisely, we find a strong negative relationship between the importance (sensitivity) of a species and its equilibrium abundance within all consumer groups and a weaker, but significant, relationship for producer species. The results from this study suggest that rare species can act as keystones through their effect on both community resilience and community structure, regardless of its trophic position. In Paper III we evaluate the risk of food web collapse caused by different trait-based extinction scenarios. In previous studies, groups of species, e.g. rare species, large-bodied species and top predators, have been identified to be relatively more prone to extinctions and other studies have found that extinctions of such species have comparably small effects on the remaining community. Using mathematical models of species dynamics we study the response of ecological communities to species removal (i.e. the proportion of species needed to be primarily removed to cause a 50% reduction in species richness, R50) when species are sequentially removed from the food web based on eight different traits. We show, contrary to some previous studies of sequential extinction simulations, that communities can be very vulnerable to realistic species loss. We furthermore find that the response of communities seems to depend on whether the extinction sequence follows a bottom-up or top-down direction, making it difficult to identify one particular extinction sequence as the most important/severe sequence. Finally, in Paper IV we aim to identify traits of species that can be used to identify keystone species, in terms of causing the highest proportion of secondary extinctions following their loss, in food webs with different degree of disassembly. Moreover, we analyze if the loss of a species that triggers a cascade of many secondary extinctions are the same species being identified as a keystones using Community Sensitivity Analysis. To answer these questions we randomly remove species from a set of 100 model communities. We analyze the relationship between the number of secondary extinctions following the randomly removed species and a range of species traits in communities where i) 75-100% of the initial number of species remain, ii) 50-75% of all species remain, iii) 25-50% of all species remain and iv) only 0-25% of all species remain. We find that the variation in secondary extinctions explained using species traits increases when the degree of food web disassembly and food web connectance are taken into account. The most important trait varies for different degrees of food web disassembly and also depends on whether basal species can go primarily extinct or not. However, due to correlation between most important traits, we conclude that the key status of different traits is rather robust against structural changes in the model food webs. Interestingly, food webs seem to be most sensitive to a random species loss after the loss of more than 25% of all initial species, suggesting that there is a threshold from which secondary extinctions increases. We also conclude that species being identified as keystones, based on the effect of their loss, are to some extent the same species being identified as having the largest effect on community structure and resilience, respectively, following a small perturbation.