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  • Drakou, Aleksandros (2005)
    Title: Exchange rate dynamics with pricing-to-market (PTM). This study aims to demonstrate how the presence of sticky prices and pricing-to-market practices of firms affect the exchange rate volatility as well as international macroeconomic transmission and welfare. The model utilized is a simple exchange rate framework which combines international market segmentation by competitive firms as well as local currency price setting. The main reference of the study is Betts and Devereux (2000), "Exchange rate dynamics in a model of pricing-to-market". Section 2 presents the determinants of the model, section 3 the impact of PTM to exchange rate variability, section 4 the impacts of monetary government spending shocks under PTM, and finally section 5 examines the welfare aspects. Main results are the following. PTM is important for the determination of the exchange rate as well as for international macroeconomic fluctuations. It decreases the pass-through from exchange rate changes to prices, as well as the expenditure switching effect of exchange rate variations. The presence of PTM also increases exchange rate variability. Furthermore since it causes departures from purchasing power parity, it also lessens the comovement in consumption across economies. Finally PTM influences the transmission of monetary policy shocks, thus causing vital welfare repercussions. More specifically, domestic monetary expansions raise domestic welfare while reducing foreign one. Thus monetary policy becomes a beggar thy neighbor instrument under the influence of pricing to market policies.
  • Ruokolainen, Lasse (Helsingin yliopisto, 2009)
    While environmental variation is an ubiquitous phenomenon in the natural world which has for long been appreciated by the scientific community recent changes in global climatic conditions have begun to raise consciousness about the economical, political and sociological ramifications of global climate change. Climate warming has already resulted in documented changes in ecosystem functioning, with direct repercussions on ecosystem services. While predicting the influence of ecosystem changes on vital ecosystem services can be extremely difficult, knowledge of the organisation of ecological interactions within natural communities can help us better understand climate driven changes in ecosystems. The role of environmental variation as an agent mediating population extinctions is likely to become increasingly important in the future. In previous studies population extinction risk in stochastic environmental conditions has been tied to an interaction between population density dependence and the temporal autocorrelation of environmental fluctuations. When populations interact with each other, forming ecological communities, the response of such species assemblages to environmental stochasticity can depend, e.g., on trophic structure in the food web and the similarity in species-specific responses to environmental conditions. The results presented in this thesis indicate that variation in the correlation structure between species-specific environmental responses (environmental correlation) can have important qualitative and quantitative effects on community persistence and biomass stability in autocorrelated (coloured) environments. In addition, reddened environmental stochasticity and ecological drift processes (such as demographic stochasticity and dispersal limitation) have important implications for patterns in species relative abundances and community dynamics over time and space. Our understanding of patterns in biodiversity at local and global scale can be enhanced by considering the relevance of different drift processes for community organisation and dynamics. Although the results laid out in this thesis are based on mathematical simulation models, they can be valuable in planning effective empirical studies as well as in interpreting existing empirical results. Most of the metrics considered here are directly applicable to empirical data.
  • Valosaari, Kata-Riina (Helsingin yliopisto, 2008)
    Biological invasions are considered as one of the greatest threats to biodiversity, as they may lead to disruption and homogenization of natural communities, and in the worst case, to native species extinctions. The introduction of gene modified organisms (GMOs) to agricultural, fisheries and forestry practices brings them into contact with natural populations. GMOs may appear as new invasive species if they are able to (1) invade into natural habitats or (2) hybridize with their wild relatives. The benefits of GMOs, such as increased yield or decreased use of insecticides or herbicides in cultivation, may thus be reduced due the potential risks they may cause. A careful ecological risk analysis therefore has to precede any responsible GMO introduction. In this thesis I study ecological invasion in relation to GMOs, and what kind of consequences invasion may have in natural populations. A set of theoretical models that combine life-history evolution, population dynamics, and population genetics were developed for the hazard identification part of ecological risks assessment of GMOs. In addition, the potential benefits of GMOs in management of an invasive pest were analyzed. In the first study I showed that a population that is fluctuating due to scramble-type density dependence (due to, e.g., nutrient competition in plants) may be invaded by a population that is relatively more limited by a resource (e.g., light in plants) that is a cause of contest-type density dependence. This result emphasises the higher risk of invasion in unstable environments. The next two studies focused on escape of a growth hormone (GH) transgenic fish into a natural population. The results showed that previous models may have given too pessimistic a view of the so called Trojan gene -effect, where the invading genotype is harmful for the population as a whole. The previously suggested population extinctions did not occur in my studies, since the changes in mating preferences caused by the GH-fish were be ameliorated by decreased level of competition. The GH-invaders may also have to exceed a threshold density before invasion can be successful. I also showed that the prevalence of mature parr (aka. sneaker) strategy among GH-fish may have clear effect on invasion outcome. The fourth study assessed the risks and developed methods against the invasion of the Colorado Potato Beetle (CPB, Leptinotarsa decemlineata). I showed that the eradication of CPB is most important for the prevention of their establishment, but the cultivation of transgenic Bt-potato could also be effective. In general, my results emphasise that invasion of transgenic species or genotypes to be possible under certain realistic conditions and resulting in competitive exclusion, population decline through outbreeding depression and genotypic displacement of native species. Ecological risk assessment should regard the decline and displacement of the wild genotype by an introduced one as a consequence that is as serious as the population extinction. It will also be crucial to take into account different kinds of behavioural differences among species when assessing the possible hazards that GMOs may cause if escaped. The benefits found of GMO crops effectiveness in pest management may also be too optimistic since CPB may evolve resistance to Bt-toxin. The models in this thesis could be further applied in case specific risk assessment of GMOs by supplementing them with detailed data of the species biology, the effect of the transgene introduced to the species, and also the characteristics of the populations or the environments in the risk of being invaded.
  • Magnusson, Roland Lars Johannes (2006)
    Over the last fifteen years, the connection between free trade and the environment has been the subject of considerable debate. Among other things, it has been proposed that freer trade may harm the environment if it induces national governments to compete by undercutting each others’ environmental standards. We assess this proposition in a federal economy with free movement of capital and goods, but labour that is immobile. Our analysis shows that if the member states are small, firms perfectly competitive and pollution non-transboundary, the national governments’ choice of environmental standards coincide with that of the federal government’s. However, if the third assumption is relaxed, without cooperation, all states choose less strict standards than the federal government, even if pollution is only partially transboundary. If we assume monopolistically instead of perfectly competitive firms, the result that non-cooperative regulations are federally efficient when pollution is non-transboundary holds no longer. Nonetheless, there is nothing to suggest that environmental policy is less strict under non-cooperation than under cooperation. Intuitively, this is because the choice of emission tax by one country imposes a number externalities on the other. These externalities are partly positive and partly negative. Without assigning values to at least one of the model’s parameters, we are not able to say whether the negative or the positive externalities dominate, that is, whether the non-cooperative equilibrium is characterised ecological dumping or not-in-my-back-yard. In the special case of perfectly transboundary pollution, we find that ecological dumping occurs regardless of the choice of values for the model’s other parameters. We contribute to the literature in three ways. First, we show that the existence of pollution that spills from one country into another works in favour of ecological dumping both in perfect and in monopolistic product market competition. Second, we show that for ecological dumping to occur, a priori, pollution must be perfectly transboundary if firms are monopolistically competitive, whereas it suffices that pollution is partially transboundary if firms are perfectly competitive. Third, we show that perfect competition, and the standard results associated with it are obtained as a special case of monopolistic competition when the monopolistically competitive firms’ market power is eliminated.
  • Magnusson, Roland (Helsingin yliopisto, 2006)
    Over the last fifteen years, the connection between free trade and the environment has been the subject of considerable debate. Among other things, it has been proposed that freer trade may harm the environment if it induces national governments to compete by undercutting each others environmental standards. We assess this proposition in a federal economy with free movement of capital and goods, but labour that is immobile. Our analysis shows that if the member states are small, firms perfectly competitive and pollution non-transboundary, the national governments choice of environmental standards coincide with that of the federal government s. However, if the third assumption is relaxed, without cooperation, all states choose less strict standards than the federal government, even if pollution is only partially transboundary. If we assume monopolistically instead of perfectly competitive firms, the result that non-cooperative regulations are federally efficient when pollution is non-transboundary holds no longer. Nonetheless, there is nothing to suggest that environmental policy is less strict under non-cooperation than under cooperation. Intuitively, this is because the choice of emission tax by one country imposes a number externalities on the other. These externalities are partly positive and partly negative. Without assigning values to at least one of the model s parameters, we are not able to say whether the negative or the positive externalities dominate, that is, whether the non-cooperative equilibrium is characterised ecological dumping or not-in-my-back-yard. In the special case of perfectly transboundary pollution, we find that ecological dumping occurs regardless of the choice of values for the model s other parameters. We contribute to the literature in three ways. First, we show that the existence of pollution that spills from one country into another works in favour of ecological dumping both in perfect and in monopolistic product market competition. Second, we show that for ecological dumping to occur, a priori, pollution must be perfectly transboundary if firms are monopolistically competitive, whereas it suffices that pollution is partially transboundary if firms are perfectly competitive. Third, we show that perfect competition, and the standard results associated with it are obtained as a special case of monopolistic competition when the monopolistically competitive firms market power is eliminated.
  • Vainio, Eeva Johanna (Helsingin yliopisto, 2008)
    Wood decay fungi belonging to the species complex Heterobasidion annosum sensu lato are among the most common and economically important species causing root rot and stem decay in conifers of the northern temperate regions. New infections by these pathogens can be suppressed by tree stump treatments using chemical or biological control agents. In Finland, the corticiaceous fungus Phlebiopsis gigantea has been formulated into a commercial biocontrol agent called Rotstop (Verdera Ltd.). This thesis addresses the ecological impacts of Rotstop biocontrol treatment on the mycoflora of conifer stumps. Locally, fungal communities within Rotstop-treated and untreated stumps were analyzed using a novel method based on DGGE profiling of small subunit ribosomal DNA fragments amplified directly from wood samples. Population analyses for P. gigantea and H. annosum s.l. were conducted to evaluate possible risks associated with local and/or global distribution of the Rotstop strain. Based on molecular community profiling by DGGE, we detected a few individual wood-inhabiting fungal species (OTUs) that seemed to have suffered or benefited from the Rotstop biocontrol treatment. The DGGE analyses also revealed fungal diversity not retrieved by cultivation and some fungal sequence types untypical for decomposing conifer wood. However, statistical analysis of DGGE community profiles obtained from Rotstop-treated and untreated conifer stumps revealed that the Rotstop treatment had not caused a statistically significant reduction in the species diversity of wood-inhabiting fungi within our experimental forest plots. Locally, ISSR genotyping of cultured P. gigantea strains showed that the Rotstop biocontrol strain was capable of surviving up to six years within treated Norway spruce stumps, while in Scots pine stumps it was sooner replaced by successor fungal species. In addition, the spread of resident P. gigantea strains into Rotstop-treated forest stands seemed effective in preventing the formation of genetically monomorphic populations in the short run. On a global scale, we detected a considerable level of genetic differentiation between the interfertile European and North American populations of P. gigantea. These results strongly suggest that local biocontrol strains should be used in order to prevent global spread of P. gigantea and hybrid formation between geographically isolated populations. The population analysis for H. annosum s.l. revealed a collection of Chinese fungal strains that showed a high degree of laboratory fertility with three different allopatric H. annosum s.l. taxa. However, based on the molecular markers, the Chinese strains could be clearly affiliated with the H. parviporum taxonomical cluster, which thus appears to have a continuous distribution range from Europe through southern Siberia to northern China. Keywords: Rotstop, wood decay, DGGE, ISSR fingerprinting, ribosomal DNA
  • Macias Fauria, Marc (Helsingin yliopisto, 2008)
    Ecological processes are controlled to varying degrees by climate. Large-scale climatic patterns (teleconnections) control the frequency of local weather phenomena over large regions (continents to hemispheres) and at different timescales (days to decades). This Ph.D. aims to explain how large-scale climate patterns synchronize a set of ecological processes northern coniferous forests (tree-ring growth, large area burnt by wildfire, and tree-mortality caused by mountain pine beetle) through controlling the frequency, duration, and spatial correlation of key local weather variables over large areas. Methodology was based on obtaining long complete ecological and climatic records and applying a variety of timeseries analyses in order to find out if climate and populations were related, and the nature and extent of such relationships, within a framework defined by knowledge on both the biological and the physical characteristics of the studied interactions. The description of the mechanisms through which such teleconnections control population traits is essential in these studies. Research on timeseries allowed the development of new methods to deal with highly autocorrelated data. Overall, the studied processes were strongly related with and synchronized by large-scale climate. Mountain ranges played a major role in creating regional climatic gradients and thus strongly influenced relationships between climate and the ecological processes. Moreover, land use (grazing in this case) strongly affected the relationships between ecological processes (tree-growth) and climate. Relationships between climate and ecological processes were found to be highly dynamic and to have changed during the 20th century, driven in part by long-term climatic changes and by internal variability of large-scale climate patterns. Finally, an environmental multi-proxy reconstruction is presented using regional relationships between climate and proxy records.
  • Lilja, Saara (Helsingin yliopisto, 2006)
    The first aim of this thesis was to explore the structural characteristics of near-natural forests and to quantify how human utilization has changed them. For this, we examined the stand characteristics in Norway spruce Picea abies (L.) Karst-dominated old-growth stands in northwestern Russia and in old Scots pine Pinus sylvestris L.-dominated stands in three regions from southern Finland to northwestern Russia. In the second study, we also compared stands with different degrees of human impact, from near-natural stands and stands selectively cut in the past to managed stands. Secondly, we used an experimental approach to study the short-term effects of different restorative treatments on forest structure and regeneration in managed Picea abies stands in southern Finland. Restorative treatments consisted of a partial cut combined with three levels of coarse woody debris retention, and a fire/no-fire treatment. In addition, we examined burned and unburned reference stands without cutting treatments. Results from near-natural Picea abies forests emphasize the dynamic character of old-growth forests, the variety of late-successional forest structures, and the fact that extended time periods are needed to attain certain late-successional stages with specific structural and habitat attributes, such as large-diameter deciduous trees and a variety of deadwood. The results from old Pinus sylvestris-dominated forests showed that human impact in the form of forest utilization and fire exclusion has strongly modified and reduced the structural complexity of stands. Consequently, small protected forest fragments in Finland may not serve as valid natural reference areas for forest restoration. However, results from the restoration experiment showed that early-successional natural stand characteristics can be restored to structurally impoverished managed Picea abies stands, despite a significant portion of wood volume being harvested. A variety of restoration methods is needed, due to differences in the condition of the forest when restoration is initiated and the variety of successional stages of forest structures after anthropogenic and natural disturbances. Keywords: dead wood, disturbance dynamic, fire, near-natural stand, rehabilitation, succession
  • Laaka-Lindberg, Sanna (Helsingin yliopisto, 2000)
  • Kolehmainen, Johanna (Helsingin yliopisto, 2008)
    The ongoing rapid fragmentation of tropical forests is a major threat to global biodiversity. This is because many of the tropical forests are so-called biodiversity 'hotspots', areas that host exceptional species richness and concentrations of endemic species. Forest fragmentation has negative ecological and genetic consequences for plant survival. Proposed reasons for plant species' loss in forest fragments are, e.g., abiotic edge effects, altered species interactions, increased genetic drift, and inbreeding depression. To be able to conserve plants in forest fragments, the ecological and genetic processes that threaten the species have to be understood. That is possible only after obtaining adequate information on their biology, including taxonomy, life history, reproduction, and spatial and genetic structure of the populations. In this research, I focused on the African violet (genus Saintpaulia), a little-studied conservation flagship from the Eastern Arc Mountains and Coastal Forests hotspot of Tanzania and Kenya. The main objective of the research was to increase understanding of the life history, ecology and population genetics of Saintpaulia that is needed for the design of appropriate conservation measures. A further aim was to provide population-level insights into the difficult taxonomy of Saintpaulia. Ecological field work was conducted in a relatively little fragmented protected forest in the Amani Nature Reserve in the East Usambara Mountains, in northeastern Tanzania, complemented by population genetic laboratory work and ecological experiments in Helsinki, Finland. All components of the research were conducted with Saintpaulia ionantha ssp. grotei, which forms a taxonomically controversial population complex in the study area. My results suggest that Saintpaulia has good reproductive performance in forests with low disturbance levels in the East Usambara Mountains. Another important finding was that seed production depends on sufficient pollinator service. The availability of pollinators should thus be considered in the in situ management of threatened populations. Dynamic population stage structures were observed suggesting that the studied populations are demographically viable. High mortality of seedlings and juveniles was observed during the dry season but this was compensated by ample recruitment of new seedlings after the rainy season. Reduced tree canopy closure and substrate quality are likely to exacerbate seedling and juvenile mortality, and, therefore, forest fragmentation and disturbance are serious threats to the regeneration of Saintpaulia. Restoration of sufficient shade to enhance seedling establishment is an important conservation measure in populations located in disturbed habitats. Long-term demographic monitoring, which enables the forecasting of a population s future, is also recommended in disturbed habitats. High genetic diversities were observed in the populations, which suggest that they possess the variation that is needed for evolutionary responses in a changing environment. Thus, genetic management of the studied populations does not seem necessary as long as the habitats remain favourable for Saintpaulia. The observed high levels of inbreeding in some of the populations, and the reduced fitness of the inbred progeny compared to the outbred progeny, as revealed by the hand-pollination experiment, indicate that inbreeding and inbreeding depression are potential mechanisms contributing to the extinction of Saintpaulia populations. The relatively weak genetic divergence of the three different morphotypes of Saintpaulia ionantha ssp. grotei lend support to the hypothesis that the populations in the Usambara/lowlands region represent a segregating metapopulation (or metapopulations), where subpopulations are adapting to their particular environments. The partial genetic and phenological integrity, and the distinct trailing habit of the morphotype 'grotei' would, however, justify its placement in a taxonomic rank of its own, perhaps in a subspecific rank.
  • Saarinen, Juha (Helsingin yliopisto, 2014)
    The climatic cooling during the Cenozoic (65 Ma present) culminated in the Pleistocene Ice Ages (ca. 2.6 Ma 10 000 BP) during which the global climate oscillated between relatively warm climatic phases and very cold and dry glacial phases when extensive continental glaciers formed in the Northern hemisphere. The oscillation between the cold and warm climatic stages caused dramatic cyclic changes in the structure of vegetation varying at its extreme between relatively humid forests and very dry and cold mammoth steppes in Europe. These constantly changing and harsh climatic and environmental conditions caused strong extinction and evolution pressures on mammal species. In this thesis I will discuss how two major ecometric variables, body size and diet, of large herbivorous land mammals have varied during the Pleistocene and how these patterns are connected with climate, environmental conditions and competing mammal species. Mammals diversified and started to occupy the niches of large vertebrates after the Late Cretaceous mass extinction which caused the extinction of large non-avian dinosaurs. The frequency of maximum body size in archaic mammal orders shows a significant global peak in the Middle Eocene (ca. 40 Ma) as a result of the diversification and niche filling after the Late Cretaceous mass extinction, but after that maximum size frequency in mammal orders was low until it peaked significantly again the Pleistocene Ice Ages. This indicates that the Pleistocene climatic and environmental conditions favoured particularly large body sizes in mammals. The overall harshness of the Ice Age climate (seasonal, mostly cold and dry conditions and often rapid climatic changes) could have favoured large body sizes in large terrestrial mammals through mechanisms which are more complicated than the often cited benefit of large size for heat conservation (Bergmann s rule). Large size increases the ability to survive over seasonal shortages of resources such as food and water and enables long-distance migrations to areas of better resource availability. On the other hand, strong erosional processes caused by glaciers produced fertile soils and harsh climates reduced the chemical defences of plants, which resulted in seasonally high primary production and plant quality, which would have enabled herbivorous mammals to grow into large sizes during seasons of high productivity. The main factor driving fine-scale body size variations in ungulate populations has been shown by several studies to be resource availability, which is regulated by primary productivity, plant quality, population densities of the ungulate species (intraspecific resource competition) and interspecific resource competition. The comparisons of ungulate body sizes from Middle and Late Pleistocene of Britain and Germany with vegetation openness (percentages of non-arboreal pollen from associated pollen records) show that species with different ecological strategies have different body size patterns in relation to the vegetation structure. The connection between body size patterns and ecological strategies could explain the different responses of body size to vegetation openness. Species which tend to have relatively small group sizes (e.g. deer) show on average larger body sizes in environments where the vegetation structure is open, whereas gregarious, open adapted species (e.g. horses) tend to have smaller average body sizes in open habitats. I suggest this is because open habitats favour large body size in ecologically flexible species with small group sizes due to high resource availability and quality per an individual (relatively low population densities), less size-restricted manoeuvrability and enhanced capability to escape predators, whereas resource limitations for each individual caused by high population densities can become a limiting factor for individual body size in open-adapted, gregarious species which are efficient open-vegetation feeders and form large groups in open habitats. In closed environments, the body size of the open-adapted, gregarious species is not limited by high population density which enables them to attain larger individual sizes. Dietary signals of the key ungulate species in Middle and Late Pleistocene Europe based on mesowear analyses are on average significantly positively correlated with vegetation openness (non-arboreal pollen percentages) at locality-level. However, there are significant interspecific differences. While most of the species show positive correlations between their mesowear signal and non-arboreal vegetation, others, especially the red deer (Cervus elaphus), do not show any correlation. Instead, the mesowear signal of the red deer is significantly more abrasive dominated when other browse-dominated feeders, especially the roe deer (Capreolus capreolus) are present. This indicates that interspecific competition can obscure the effect of available plant material in the diet of ecologically flexible species. This should be taken into account when interpreting the feeding ecology of the key species in palaeocommunities, and especially when attempting to reconstruct palaeoenvironmental conditions from dietary proxies of mammals. Such attempts should ideally be based on as complete dietary analyses of fossil herbivore faunas as possible. In order to extend the palaeodietary and palaeoecological analyses based on mesowear signals of herbivorous mammas, a new tooth wear -based dietary analysis method was developed for elephants and other lamellar toothed proboscideans, based on measuring occlusal relief of their molar teeth as angles. The benefits of that approach compared with other available methods are that it is easy-to-do, fast and robust, and it gives consistent and comparable results for species with different dental morphologies. The preliminary results from that study indicate that the angle measurement method is a powerful tool for reconstructing proboscidean diets from the fossil record.
  • Yrttiaho, Pihla (2013)
    The subject of the research was the expectations of Finnish consumers in electronic commerce, especially concentrating on electronic products. The goal was to find out which underlying characteristics arise when the valuations of online shopping are surveyed. These dimensions were also compared to the background variables. In addition the point of interest was on expectations on delivery, payment and customer service. The research was conducted with a questionnaire form using a convenience sample. The survey was conducted in the areas of Helsinki, Espoo, Vantaa, Kotka and Turku. The aim was to reach different aged Finnish respondents, who were on the moment of the survey 16 years or older. The final sample consisted of 103 respondents. The data was analysed mainly with a Principle Component Analysis and further tests were made using the Analysis of Variance and t-tests. According to the Principle Component Analysis the characteristics of e-commerce in Finland were: privacy control, delivery, mobile-shopping, complete price, Finnish service language and design & navigation. These components followed mostly the original dimensions that were based on earlier research. However a new component of Finnish service language was found. Based on t-tests women valued privacy, mobile-shopping and design more than men. Differences according to the place of residence were examined in the same way. According to this research respondents living outside the capital area value Finnish service language in ecommerce more the residents of capital area. Approximately half of the respondents preferred to pay their purchases using online banking. The second most popular method was a credit card. Most of the respondents expect the package to arrive in 4 to 5 days from the ordering. Over half would pick up the parcel from the post office and approximately one fifth chose the home delivery. The traditional customer service mediums were the most preferred. Together over 90 percent of the respondents would contact the customer service by phone and by e-mail.
  • Favada, Ibrahim (2007)
    This dissertation examines the short- and long-run impacts of timber prices and other factors affecting NIPF owners' timber harvesting and timber stocking decisions. The utility-based Faustmann model provides testable hypotheses of the exogenous variables retained in the timber supply analysis. The timber stock function, derived from a two-period biomass harvesting model, is estimated using a two-step GMM estimator based on balanced panel data from 1983 to 1991. Timber supply functions are estimated using a Tobit model adjusted for heteroscedasticity and nonnormality of errors based on panel data from 1994 to 1998. Results show that if specification analysis of the Tobit model is ignored, inconsistency and biasedness can have a marked effect on parameter estimates. The empirical results show that owner's age is the single most important factor determining timber stock; timber price is the single most important factor in harvesting decision. The results of the timber supply estimations can be interpreted using utility-based Faustmann model of a forest owner who values a growing timber in situ.
  • Salenius, Fredrik (2014)
    Fishing vessels run on fossil fuels that produce greenhouse gases, which are harmful to the environment and costly to society. Since fuel use in fisheries is often subsidized through tax concessions, private fuel consumption will be higher than what is socially optimal. Furthermore,fuel tax concessions will lead to greater fishing effort, with overfishing as a possible consequence. This thesis deals with these negative externalities associated with fisheries. The aim of the study is to elicit the economic and environmental effects fromremoving fuel tax concessions, and to view these effects in relation to the results of current and optimal fisheries management.To this end, four different fuel costscenarios are introducedas basis for the analysis.The current situation of the fishery is compared to an optimized fishery with fuel tax concessions maintained andremoved, i.e. with fuel costs implemented. The target of the studyis thecommercial Baltic salmon fishery, which is a small-scale coastal fishery carried out with trapnets. The analysis employs a bioeconomic model, which accounts for the economic and biological features of this specific fishery. Results from the analysis conveyed that the fishery is currently unprofitable, and therefore not capable of coping withadditional costsimposed on it. However, results from the optimization suggest that economic performance can be improvedby managing the fishery in an optimal way, i.e. by adjustingthe fishing effort to an efficient level. Furthermore, amovement to optimal management is suggested to be an efficient way of gaining both economic and environmental benefits. An optimally managed fishery is thus better equipped to pay for the external costs fromtheCO2 emissions arising from its fishing operations.
  • Natunen, Anu (2002)
    The Asian crisis in 1997-98 was different to prior crises experienced in Europe (1992-93) and Mexico (1994-95). In the Asian crisis shock sensitivity seemed to be liked to financial weaknesses and other structural fragilities rather than weak macroeconomic fundamentals. Banks extended credits, enterprises were indebted with greater leverage and money was invested in the real estate even though investments’ output was not always productive. Credit availability increased as banks competed for customers, cutting back ex ante screening of projects and customer monitoring. Several researches have identified moral hazard caused by government bailout guarantees as the origin of the financial vulnerability in Asia at the time of crisis, explaining the irresponsible behavior of the corporate sector, banking sector, and investors. Due to the crisis’s microeconomic nature the traditional first- and second-generation currency crises models were not able to explain the Asian currency crisis and as a result third-generation models have emerged. This thesis aims to find answers to the following questions: (1) what was relevant in the Asian currency crisis, (2) when governments use exchange rates policies to bailout troubled companies, how can these bailout policies be explained theoretically, and (3) what other factors can affect the functionality of these exchange rate policies as bailout, when are they not a solution. In other words this paper presents an empirical and a theoretical approach to the Asian currency crisis and analyzes to what extent theoretical explanations are supported by empirical evidence. As a theoretical explanation to the Asian currency crisis this thesis presents a third-generation currency crises model by Bris and Koskinen (2002), based on an argument that bailing out financially distressed export companies through currency devaluation is optimal ex post for an economy. As a competing point of view to the model of Bris and Koskinen on the affect of devaluation on corporate sector, the paper presents a review of the theoretical work of Aghion et al. (2000) on currency crises, who argue that currency devaluation leads to further corporate balance-sheet deteriorating. Empirical evidence on the Asian currency crisis supports the implications of the model of Bris and Koskinen.
  • Leivo, Tiina (Helsingin yliopisto, 2001)
  • Saleh, Raya (2000)
    The conflict between economic growth and environmental quality is very complex. Many believe that environmental concerns depend on the GNP levels of countries. It is against this background that we formulated the problem of the study, to examine the complex relationship between externalities and income level using the overlapping generations model of economic growth and environmental externalities. According to the overlapping generations model the solution to externality problem is a function of individual choices and planner's policies. The model shows us that economies can have both economic growth and clean environment if the following conditions are fulfilled: First individuals have to give up a large amount of consumption in return for improvement in the environmental quality therefore and according to the overlapping generations model the individual decisions has long lasting effects on both factors productivity and environment. Second, the planner has to set policies to control population growth since population growth leads to low capital and poor environment. Third, the planner has to implement a tax transfer scheme which will be optimal to solve the externalities problem not for only the current generations but also for future generations as well. The overlapping generations model of economic growth and environmental quality provides theoretical explanations in analysing the competitive equilibrium in the steady-state. And obtain also the golden rule and achieve the optimal level of allocation. The model concludes that the optimal path towards pollution reduction is to keep a low population growth and low consumption in order to have a clean environment regardless the GNP level or the individuals income level since high consumption cause degradation of the environment.