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Human alteration of the global nitrogen (N) cycle has had major impacts on naturally N-limited ecosystems worldwide. Peatlands, dominated by peat mosses, Sphagnum species, represent one such sensitive ecosystem. I have studied how this ecosystem is affected by increased N availability, using a small-scale N fertilization experiment in combination with a gradient study of three peatlands with varying N deposition. I found both in the experiment and in the gradient a similar pattern of Sphagnum decline accompanied by an increase of vascular plants associated with enhanced N supply. For one common Sphagnum species - both in the experiment and in the gradient study - I also found an identical, linear increase in soluble amino acid N (NAA) accumulation. As soluble amino acids function as N storage compounds among Sphagna, NAA is a suitable measure for Sphagnum N status, and indicates accumulation of excess N not used for growth. My results show that NAA can be used as a sensitive indicator to signal N pollution before the slow, and gradual, regime shift from Sphagnum to vascular plant dominance is visible. In an N-uptake experiment using Sphagnum specimens from the three peatlands varying in N deposition, I found a reduced N-uptake by both investigated Sphagnum species from a high N deposition site, in south-western Sweden. This potential of Sphagna to adjust to high N loads through N uptake regulation will, however, not prevent tissue N accumulation, and as a result a shift from Sphagnum to vascular plant dominance. In general I found similar patterns of N induced changes both in Sphagnum tissue chemistry and vegetation structure in the experiment and along the gradient study. Thus, I conclude that long-term, small-scale field experiments seem to offer reliable estimates of both the direction and strength of key vegetation responses in Sphagnum dominated peatlands. This is likely related to the key role of Sphagna as ecosystem engineers. In the experiment I found a marked time lag in vegetation response to N application treatments. The closed Sphagnum carpet did not collapse until after eight years of continuous treatments. Another result was that dwarf shrubs, e.g. cranberry Vaccinium oxycoccos, first increased, but later declined due to severe attacks by fungal diseases. One important conclusion is that long-term, manipulative field experiments are necessary for our ability to understand how ecosystems will respond to environmental change.

There is a recent emergence of open government initiatives for citizen participation in policy making in China. Open government initiatives seek to increase the level of participation, deliberation and transparency in government affairs, sometimes by use of Internet fora. In contemporary political science the introduction of these initiatives in authoritarian contexts has been described as a paradox of authoritarian deliberation. This thesis uses cybernetic theory, perspectives of information steering in all systems, to resolve the paradox and present a new view on authoritarianism and autocracy. A cybernetic definition of autocracy allows for an analysis of different types of autocracy in different models of governance. The theoretical tools developed are used to define and assess the potential for democratic autocracy, representative autocracy, deliberative autocracy and collaborative autocracy in online open government initiatives in China.   The argument of the thesis is that these initiatives must be understood within the environment in which they are introduced. In the case of the Chinese online environment, individuals often have limited possibilities of acting anonymously. To explore how online identity registration affects citizens, a lab-in-the-field experiment was set up. Chinese university students were invited to engage with a government sponsored online forum under conditions of both anonymity and identity registration. Previous research suggests that anonymity would lead users of online fora to be more active and produce more content. This hypothesis was partly proven false by the experiment. This study shows that users who have their identities registered, sometimes even produce more content. The study also shows that registered users tend to act against their own preferences and participate more in nationalistic debates. The concluding discussion is focused on the wider implications of these effects. If citizens are incentivized to channel their dissatisfaction as loyalty, rather than voice or exit, they might become complicit in sustaining authoritarianism. Interviews with experiment participants show that open government initiatives primarily enable deliberative and collaborative autocracy when introduced in the Chinese online environment. This has the potential of increasing the amount of dissatisfaction that citizens channel as loyalty via mechanisms of authoritarian collaboration.

The world is facing a global climate crisis and a collective step towards a more sustainable lifestyle is of importance. Food consumption accounts for a large part of an individuals’ total emissions and as the production of meat generally emits less green-house-gases than that of plant-based alternatives, changing towards a more plant-based diet can be one step to a more sustainable lifestyle. This study outlines a field experiment at a university cafeteria where the menu order was altered by random assignment. It is tested if placing the vegetarian option at the top of the menu has a causal effect on the share of vegetarian option sold that day, i.e. if it is possible to nudge customers to choose a more sustainable option. Using ordinary least squares and a beta regression models, the results do not show a positive treatment effect on the share of vegetarian option sold but do find a significantly average negative effect of 5.5 percentage points on the share of meat option sold. This effect it translated to an average negative effect of 6 percent on the daily emissions due to food sales at the cafeteria.

To investigate whether there is unequal treatment for ethnic minorities in the sharing economy this paper conducts a field experiment on Airbnb in Sweden. The key findings report that inquiries from guests with Arabic-sounding names are 17 percentage points less likely to receive a booking invitation compared to guests with Swedish-sounding names. The discrimination is robust across host and listing characteristics. Furthermore, the results show that being associated with a lower social class decreases the probability of receiving a booking invitation for guests with Arabic-sounding names but not for guests with Swedish-sounding names, suggesting that the signal of social class is stronger for guests with Arabic-sounding names.

A relação entre preço e posicionamento de produto nas prateleiras de varejo ainda tem espaço para descobertas na literatura de marketing. O objetivo central dessa dissertação foi identificar o efeito do posicionamento de produtos levando em consideração o seu preço e a escolha do consumidor; mais especificamente o efeito positivo do posicionamento lógico de preços (i.e produtos posicionados do menor ao maior preço nas prateleiras) na escolha final, facilidade de escolha e número de unidades vendidas. Dois estudos foram feitos em busca de resultados, o primeiro sendo um experimento online, no qual escolha e facilidade de escolha foram estudadas a partir do posicionamento de preço. O segundo estudo foi um experimento de campo, no qual unidades vendidas foram verificadas através do posicionamento de preço. Os resultados encontrados em ambos os estudos indicam que o posicionamento de produtos a partir de uma ordem lógica de preço afeta a escolha do consumidor, embora não através da facilidade de escolha, e, mais ainda, afeta positivamente a quantidade de produtos vendidos. Contudo, verificou-se que o posicionamento a partir de preço não tem como consequência a facilidade de escolha. / The relationship between price and product positioning on retail shelves still has room for breakthroughs in marketing literature. The main goal of this dissertation was to identify the effect of product placement, taking into account its price, and consumer choice; more specifically, the positive effect of product placement by a logical positioning of prices (i.e. products positioned from the lowest to the highest price on the shelves) on the final choice, choice easiness and overall number of units sold. Two studies were conducted to search for these results, the first one as an online experiment, which studied choice and choice easiness from price positioning. In this first study was found that there is a positive relation between logical price arrangement (i.e. positioning products from the cheapest to the most expensive one) and consumer choice. However, price positioning does not significantly affect the ease of choice. The second study was a field experiment, in which the overall number of units sold was verified through price positioning. The results found in both studies indicate that the positioning of products from a logical price order affects consumer choice, though not through easiness of choice and, moreover, positively affects the quantity of products sold. Yet, it has been found that considering primily price to choose a shelf position does not have as consequence easiness of choice.

This thesis presents a field experiment on the topic of ethnic discrimination in the contact between citizens and local Swedish politicians. A correspondence technique was used to investigate whether ethnicity affects how responsive Municipal Commissioners are to questions regarding school politics. By sending an email to each Municipal Commissioner, randomising whether a putative Arabic or Swedish alias was used, it aimed to find potentialpatterns in how different groups of citizens are treated by their local political representatives. In total, eight fictitious individuals were created which each contained a unique mixture of ethnicity, gender and socioeconomic status. In general, the result shows no statistically significant signs of discrimination of individuals with Arabic-sounding names. Evidence of gender disparities among Arabic individuals was neither found. However, Arabic females are significantly less likely to receive a reply than Swedish females. Furthermore, the result indicates that socioeconomic status affects political responsiveness toward individuals with Arabic background. This should be considered problematic and noteworthy in the case of Sweden, given its reputation of being a highly egalitarian and well-functioning democracy. The findings further stress the importance to acknowledge that different categories of social identities may interact with ethnic discrimination. This consequently calls upon appropriate approaches to study it.

<p>Never before has the interest for charity been greater. At this writing, U.S. charities have collected nearly one billion U.S. dollars (!) only in the aid for the disaster victims in Haiti.But can you get people to give even more? Are there yet unexplored market in which charitable organizations still have growth potential? Traditional economic theory which is based in individuals' rational behavior and self-utility maximization has a hard time to explain the phenomenon of charitable donations. But relatively new research can possibly connect the theory and the phenomenon through the theorem of warm-glow in why people actually donate money anonymously and indirectly to people they never met or will ever know who made the donation. This thesis will examine whether or not a small change in the environment could influence individuals to donate more money and / or more frequently. The study was conducted as a field experiment at an ICA store deposit station where people are faced with the choice to donate their deposit to the Swedish Red Cross instead of getting a voucher for themselves. The obtained results shows a statistically significant difference between the donation of the pledge of over 13 percentage more in the presence of a visual stimulus, more specifically a picture of a poor boy drinking clean water from a tap. That results in a doubling in nominal amounts of donations for the charity. Moreover, I find that people who already before the experiment are sympathetic to donating the pledge do so to a greater extent than people who were not. Neither sex nor age seemed to affect the results in any way.</p>

Never before has the interest for charity been greater. At this writing, U.S. charities have collected nearly one billion U.S. dollars (!) only in the aid for the disaster victims in Haiti.But can you get people to give even more? Are there yet unexplored market in which charitable organizations still have growth potential? Traditional economic theory which is based in individuals' rational behavior and self-utility maximization has a hard time to explain the phenomenon of charitable donations. But relatively new research can possibly connect the theory and the phenomenon through the theorem of warm-glow in why people actually donate money anonymously and indirectly to people they never met or will ever know who made the donation. This thesis will examine whether or not a small change in the environment could influence individuals to donate more money and / or more frequently. The study was conducted as a field experiment at an ICA store deposit station where people are faced with the choice to donate their deposit to the Swedish Red Cross instead of getting a voucher for themselves. The obtained results shows a statistically significant difference between the donation of the pledge of over 13 percentage more in the presence of a visual stimulus, more specifically a picture of a poor boy drinking clean water from a tap. That results in a doubling in nominal amounts of donations for the charity. Moreover, I find that people who already before the experiment are sympathetic to donating the pledge do so to a greater extent than people who were not. Neither sex nor age seemed to affect the results in any way.

Nitrogen (N) is an essential plant nutrient, widely applied as N-fertilizer to improve yields of agriculturally important crops. An alternative to fertilizer use could be the exploitation of plant growth-promoting bacteria, capable of enhancing growth and yield of many plant species. Azospirillum and Gluconacetobacter are root colonizing, free-living, N2-fixing bacteria (diazotrophs) with the potential to transfer fixed N to associated plants. The purpose of this study was to evaluate the agronomic efficiency of two diazotrophs, Azospirillum lipoferum and Gluconacetobacter azotocaptans, inoculated onto wheat. Physiological parameters and yield components were evaluated. The objectives of this study were to: 1) determine the survival of each diazotroph species on wheat seeds over time; 2) determine the survival of A. lipoferum and G. azotocaptans inoculated on wheat seed treated with a fungicide seed treatment, Dividend® XL RTA®; 3) determine if inoculation of wheat with the diazotrophs under controlled conditions causes an increase in dry matter, N2-fixation and N uptake; 4) determine if fertilizer N applied at three levels influences atmospheric N2-fixation by A. lipoferum or G. azotocaptans; 5) determine if inoculation of wheat with A. lipoferum or G. azotocaptans under field conditions causes any increase in dry matter, N2-fixation and N uptake; 6) determine if N-fertilization levels under field conditions influenced N2-fixation by A. lipoferum or G. azotocaptans. In order to meet these objectives lab, growth chamber, and field studies were completed. Laboratory investigations revealed that the decline in recovery of colony forming units (CFU) of G. azotocaptans was not significantly different (P<0.05) for any seed treatment. There was a general decrease in CFU over time regardless of seed treatment. Analysis of the recovered CFU of A. lipoferum over time showed that there was a significant difference (P<0.05) between both the non-sterilized seed and the Dividend® XL RTA® treated seed when compared sterilized seed. Recovery of CFU on sterilized seed declined at a more rapid rate compared to the other two seed treatments. Gluconacetobacter azotocaptans and A. lipoferum were not negatively influenced by the Dividend® XL RTA® seed treatment. Also, both diazotrophs were able to compete with other microorganisms that may have been on the seed coat of unsterilized seeds. Azospirillum lipoferum and G. azotocaptans were able to fix atmospheric N, but, there were no significant (P<0.05) differences between the diazotroph species. Additions of fertilizer N enhanced N2-fixation, in both the growth chamber and field studies. As the amount of fertilizer N increased, so did the %Ndfa and N uptake. In the growth chamber study, inoculated wheat, and fertilized with 12.2 and 24.5 µg N g-1 had the highest %Ndfa of 25.5%, and wheat fertilized with 24 µg N g-1 had the highest N uptake (1.3 g pot-1) at maturity. In the field study, inoculated wheat fertilized with of 80 kg N ha-1 had significantly higher (P<0.05) %Ndfa (10.5%) compared to wheat grown with the other fertilizer levels, which also corresponded to the highest N uptake in wheat plants (47 kg ha-1). The diazotrophs also affected the partitioning of N in the wheat plants differently. Wheat inoculated with A. lipoferum had significantly higher (P<0.05) amounts of N accumulated in heads of plants, and wheat inoculated with G. azotocaptans had significantly higher (P<0.05) amounts of N accumulated in stems of plants. However, this trend was not evident in the field study.