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  • Jokelainen, Antti (2023)
    The Arctic region is experiencing an intensification in the hydrological cycle due to climate change. Lakes in the Arctic respond quickly to environmental changes and act as archives to past climates. Naturally occurring stable isotopes of water, specifically the isotopes of oxygen and hydrogen, provide a valuable tool for investigating local hydrological conditions and reconstructing past climates. In this study, stable isotopes of water in Värriö, Northeastern Finland, were analyzed to gain insights into the local hydrology and assess the use of palaeoclimatological methods for reconstructing past climates. Precipitation, groundwater, and lake water were analyzed to characterize the local isotope hydrology. To assess the reconstruction of past climate conditions, a set of modern chironomid head capsules were collected and analyzed for their isotopic composition. Chironomid head capsules are commonly used to reconstruct past climate conditions. The results indicated that precipitation in Värriö is sourced from the Barents Sea to a considerable extent, which has implications for the isotopic composition of surface waters. The isotopic composition of lake water in Kuutsjärvi was found to reflect the precipitation isotopic composition well due to a lack of evaporative enrichment. The study also noted the seasonal effects of spring thaw on the lake, and the contribution of groundwater as a controller of these effects. The analysis of chironomid head capsules in this study yielded values that differed from present-day conditions. The possible reason for the offset in values was explored, but not identified. This highlights the importance of accurate calibration of chironomid head capsule values and knowledge of chironomid ecology when using this method for palaeoclimatological research. Overall, this study demonstrates the utility of stable isotopes of water for characterizing local hydrological conditions and reconstructing past climates.
  • Stuart, Elliot (2013)
    The primary characteristic of urbanisation is the addition of hard surfaces to catchments, which affects water and habitat quality in urban streams and alters natural hydrological processes by reducing infiltration, evapotranpiration and efficiently conveying storm runoff to streams, gathering a variety of urban polluants along the way. This is typical of the 'urban stream syndrome'. Catchment imperviousness (especially Effective Impervious Area or percent connectivity) can be used as one of the primary indicators of the severity of this phenomenon. This research was initiated through a collaboration between the City of Helsinki and the University of Helsinki to determine the baseline water quality of Hakuninmaanoja, a small urban stream in Helsinki, Finland, and the imperviousness of its catchment, where a pilot ecological housing development 'Kuninkaantammi' (KUNTA) will be built beginning in 2013. The purpose of the project is to assess the current characteristics of the catchment prior to the development in the headwaters of the stream. An automatic water quality monitoring station was built on the lower part of the stream approximately 200m upstream of its junction with Mätäjoki, the second largest river of Helsinki. Water Sensitive Urban Design can be used as part of a holistic stormwater treatment train to limit newly created imperviousness, and minimise the connectivity of the necessary remainder, allowing stormwater runoff to be reused, infiltrated and treated through soil media, or slowed down enough to attenuate the urban hydrograph. Some of these features such as raingardens, green roofs and detention ponds will be included in the KUNTA development for this purpose. A detailed calculation of catchment imperviousness was completed via field survey and land use categorization methods. Total Impervious Area (TIA) was determined to be 22%, Effective Impervious Area 15% and catchment wide runoff coefficient given by land use categorisation method to be 0.32. TIA is expected to increase to 30% following development of KUNTA, however EIA is not expected to increase in proportion with TIA due to planned Water Sensitive Urban Design features. Yearly runoff volumes based on each method of calculating imperviousness were estimated, as well as for the future following KUNTA development. Water quality in the stream currently is quite satisfactory in relation to other streams in Helsinki, however the urban stream syndrome is already evident with particular concern regarding temperature, sediment and peak flow fluctuations. Effective Impervious Area should be used in urban planning of new and existing developments rather than TIA because it will give much greater accuracy of runoff volumes and infiltration rates by taking into account unconnected impervious surfaces. Strengthening local solutions to reduce connectivity should be a municipal priority. Water quality monitoring will continue at the site until after KUNTA has been built, and further research should focus on determining the technical performance of stormwater Best Management Practices (BMPs) at the site.
  • Silvennoinen, Emmi (2015)
    Infiltration rates in urban areas are low due to a high proportion of impervious structures. Impermeability results in increased rates of urban runoff, which often leads to degradation in receiving waters. Stormwater retention in urban areas can be increased, for instance, with green, vegetated roofs. While impervious, normal roofs produce the runoff immediately, studies with green roofs have shown that they cause delays in peak runoff and reduce the runoff rate and volume by water retention and attenuation. The water retaining capacity of green roofs vary due to local weather conditions and roof characteristics. Several studies and experiments considering stormwater management and other ecosystem services that green roofs provide have been performed worldwide, mainly in temperate regions, while more studies are needed in cold climates especially to quantify the performance of green roofs in winter. The purpose of this thesis was to evaluate the effects of various types of precipitation events on runoff rates, timing and water retention in locally built new green roofs from late summer to early winter in southern Finland. Data on precipitation and green roof runoff as well as soil temperature and humidity were monitored automatically. Green roofs included a) precultivated readymade vegetation mats and b) built on site novel substrate mixture with plug plants and seedlings. My principal aim was to study the capability of green roofs in retaining and attenuating water in relation to the intensity and duration of precipitation, the length of the antecedent dry weather period as well as to temperature and moisture of the green roof substrate. I hypothesised that green roofs retain low intensity events better than high intensity events and more effectively in dry and warm than in wet and cold weather, being negligible at temperatures below 0 °C. Furthermore, I studied whether retention capacity can be improved by the amendment of biochar. Finally, readymade green roofs with dense vegetation was hypothesised to have better retention capacity than the newly created roofs with very sparse vegetation but only in summer due to evaporation. Based on cumulative runoff, green roofs retained 52 % of rainfall, which is close to the retention capability found in previous studies. Retention was generally higher at warm temperatures and for biochar-amended roofs, in agreement with my hypothesis. Against expectations, roofs with readymade vegetation mats had lower retention than those built on site. In summer and autumn, before freezing temperatures occurred, results were generally according to the hypotheses and previous research: retention rates decreased as rain depth or rain peak intensity increased. When the amount of rain preceding the measurement event was low, and the substrate moisture content was low, retention was better. During wintertime, results were contrary to my hypotheses: Total retention rates increased with the amount of rain and rain intensity, or when substrate moisture content increased. However, a long antecedent dry weather period resulted in better retention, especially during winter. Mean peak flow attenuation for rain events in this study was 64 % and results are in accordance with my hypothesis and previous research. Furthermore, delay times from when the rain event started to when runoff started and from rain peak to runoff peak were detected in this study, mean values of more than 1 h being comparable to what has been reported in the literature. Results from my thesis can be used to improve hydrological models for local stormwater management purposes. Furthermore, results can be compared with those of other ecological stormwater treatment methods. Possible future research topics include the functioning of green roofs during different seasons and especially during freezing and melting periods with assumedly complex hydrological interactions.
  • Nuorivaara, Essi (2021)
    In recent years, the role of economic models in guiding government policy has provoked discussion as human wellbeing and the state of the environment are threatened by multiple sustainability challenges, most notably by the ecological sustainability crisis. The mainstream economic approach has received criticism since it has not been able to solve these challenges and thus, several alternative approaches in pursuit for a just and sustainable future have gained popularity both nationally and internationally. In this thesis I focus on the wellbeing economy concept in the Finnish welfare state in the early 2020s. Wellbeing economy was introduced in Finland by the Finnish Federation for Social Affairs and Wealth (SOSTE) in 2012 to highlight the interdependency of human wellbeing and economy. The concept has since been developed and realized by different actors of the society, but it is not yet that well-known among the public. To find out the potential role of this new economic approach in the transition towards sustainable welfare society, it is important to get a clear picture of how the concept is interpreted by its advocates. Therefore, in my case study, I examined the expert narratives of wellbeing economy. My main research question is: What does the concept of wellbeing economy mean in Finland in the early 2020s? This question is complemented by two sub-questions: 1) What are the shared contents and practices associated with wellbeing economy? and 2) What are the key differences between different conceptions of wellbeing economy? The underlying disagreements in theory and in practice of wellbeing economy might impact the integrity of the concept even if the concept formulation of wellbeing economy seems consistent. I conducted seven (7) semi-structured expert interviews from five (5) different organizations during the spring 2021. The interviews were thematically analysed with a focus on the memes of neoliberal narratives and the memes of alternative narratives as well as the conflicting memes in alternative narratives. In this study, a meme is defined as the structural component of a narrative. Finally, I identified similarities and differences in these building blocks of wellbeing economy narratives between different experts. I found that there were more shared memes than differences in the experts’ conceptions of wellbeing economy. Most of the interviewees mentioned memes of neoliberal narrative. All the interviewees mentioned the alternative narrative memes connected networks, sustainability, cooperation with others, and human dignity, prosperity, and wellbeing. Most of them also considered the Covid-19 pandemic as an opportunity in crisis. However, the meme a new economic system created the greatest division in the interpretations of wellbeing economy. In conclusion, some interviewees supported the neoliberalism more clearly while others opposed this narrative, and the rest were not clearly for or against the growth-agenda. The ambiguity of the concept especially in terms of economic growth should be further discussed in addition to specifying, for instance, what is meant by sustainability and wellbeing in wellbeing economy. Further research is also needed to find out how the discussion about wellbeing economy concept will develop in Finland and internationally.
  • Serra Dominguez, Lluis (2021)
    Beta diversity (total dissimilarity) can be partitioned into two components: dissimilarity attributed to turnover and nestedness-resultant dissimilarity. Turnover refers to the variation in species identities among sites and implies the replacement of some species by others. In contrast, nestedness occurs when species-poor sites have a subset of the biota present in species-richer sites. Although disentangling the relative contribution of these two antithetic components from beta diversity can characterize species assemblages, the dissimilarity indices do not provide information on the processes generating the patterns. Conversely, Hierarchical Modelling of Species Communities (HMSC), which unifies many of the recent advantages of Joint Species Distribution Models, has proved to be the one of the best performing frameworks for unravelling the underlying mechanisms structuring ecological communities. The aim of this research is to explore the relationship between the outputs of the HMSC model and the dissimilarity indices in different communities with a wide range of parameterizations. As the observed patterns measured by the beta-diversity indices result from the underlying processes which HMSC attempts to capture, I hypothesized that both frameworks are at least partially linked to each other. To achieve this aim, I simulated the community data by following the structure of the HMSC model. For simplicity, only one environmental covariate was considered, which was scaled to 0 mean. The intercept of the HMSC model accounted for the baseline occurrence probability of the species, while the slope modeled the species responses to the environmental covariate. The HMSC-intercept and the HMSC-slope, which represent the species multivariate niches, were summarized in terms of center and spread. Simultaneously, the beta diversity indices (total, turnover and nestedness dissimilarity) were calculated from the community data. Finally, the outputs of both frameworks were related in terms of linear modelling and variation partitioning. As hypothesized, the results of this study suggest that outputs of the HMSC model are able to explain most of the variation in the beta-diversity indices, indicating that both frameworks are strongly related. By plotting the species niches (intercept and slope coefficients of the HMSC model) it is possible to determine the main axes of niche variation producing the nestedness and turnover patterns. While nestedness is generated by a shared response of the species to the environmental covariate(s), turnover is produced by variation in the species responses. Finally, the total dissimilarity index is driven by species rarity. In conclusion, the most comprehensive evaluation of the structure of ecological communities and the processes determining the diversity patterns can be achieved by combining the outputs of beta-diversity indices and the HMSC model.
  • Carlson, Helmi (2021)
    Tiivistelmä Referat – Abstract One of the major fundamental ecological questions is the composition of a species diet. The diet of a species is crucially linked to finding out its environmental requirements, and information about the possible changes in the diet is needed when studying the impact of environmental changes such as climate change on species. Siberian flying squirrel (Pteromys volans), classified as endangered in Finland, is a species living in coniferous and mixed forests. More precise information about the dietary habits of the species is needed to support conservation. The aim of my thesis was to investigate the diet composition and diet diversity of adult flying squirrels using DNA barcoding of their excrement pellets, a technique that provides highly accurate information quickly and effectively. The main research questions were whether the diet varies between sexes and seasons, whether diet has an influence on body condition and breeding success of the females, and whether diet diversity is related to the amount of suitable forest habitat near the nests. We collected faecal samples from 51 different flying squirrel individuals from two different study areas near the cities of Vaasa and Pietarsaari in June of 2020. Another set of samples from 8 individuals was collected in November 2020 in Vaasa. The collected samples were sent to a laboratory in Turku, where the DNA barcoding was conducted. I then made further statistical analyses from the laboratory results using general linear models to test my study questions. Although the sample size was too small to obtain statistically significant results for all the research questions, my results indicated that the diet of the Siberian flying squirrel differs between males and females just like its other living habits. Male flying squirrels have more diverse diet than female flying squirrels which have more specific and narrow diet, as they also have smaller home ranges during the breeding season and are more linked to their nesting forest patch compared to males. The aspect that female flying squirrels are more specialists during breeding time is crucial for the species conservation planning. DNA barcoding studies with bigger sample sizes should be done to further investigate the relationship between diet diversity and individual’s body condition and to ascertain the statistical significance to the results of this study.
  • Rautjärvi, Sini (2022)
    Urbanization is a growing trend, with most people living in cities nowadays. Understanding the relationships between people and nature is crucial, as ecological conditions are heavily influenced by human-environment interactions. According to prior research, socioeconomy and biodiversity are generally related. Low biodiversity typically correlates with poorer socioeconomic status, and vice versa. In this study, I aimed to determine whether there is a correlation between Lahti's socioeconomy (income) and biodiversity (bird and plant species richness and the urban ecosystem integrity index, UEII). Lahti is a medium sized city with an urban continuum of 54 km2. I used existing biodiversity data collected in the summer of 2021 and combined it with the most up-to-date socioeconomic data at the time, retrieved from the publicly available city of Lahti statistical database TILDA. The results of the study were contradictory to previous research, i.e., there was no relationship between biodiversity and socioeconomy. This gives us novel information about the luxury effect and its presence and opens doors for further research on the topic.
  • Eriksson, Julia (2023)
    Inflammatory bowel disease (IBD) is a chronic autoimmune disease, with recurring inflammation in the gastrointestinal tract. Although the actual cause of the disease is still unknown, many molecular and underlying pathways have been discovered. Infliximab (IFX) is an effective and safe antibody medication that specifically targets the cytokine protein TNF-α. This medication is given to IBD patients who do not respond to other conventional drugs and who face the final step of surgery. However, around 30 % of IBD patients do not respond to this medication at all and another 50 % either lose the effect over time, or need to discontinue the medication due to severe side effects. Therefore, it would be important to find a biomarker that could predict the outcome of the medication. In this study, 73 IBD patients have given blood samples both before and three months after the start of IFX medication. From these blood samples the RNA was extracted and sequenced to get the transcriptome profiles. The aim of this study is to find novel biomarkers, that could be used as a predictive tool for the outcome of the medication. Seven significantly differentially expressed genes were found before IFX treatment initiation between responders and non-responders of the medication. Additionally, a clear effect from the IFX medication was seen in the transcriptome profiles.
  • Stolt, Miira (2024)
    While using fireworks is a common seasonal tradition in Finland, it is accompanied with serious risks, such as injuries and fires. Thus, in 2018 a citizens’ initiative Rajat räiskeelle aimed to prohibit most firework-types from consumers. Despite being rejected by the Parliament, the initiative sparked an official investigation on how to decrease firework-related harm in Finland. This thesis continues to focus on the public’s stance on fireworks by studying the current controversy of fireworks in Finland through (I) the issues that are perceived as the most prominent by those, who oppose fireworks in consumers’ use and (II) inspects different measures with which to address the raised concerns, with the goal of mitigating them. My first research question’s data comes from 11 Finnish online news articles’ comment sections, that I sourced with the search term “rajat räiskeelle”. With inductive thematic analysis on the comments against private firework use, emerging themes indicate the main issues associated with the practice of using fireworks. The second research question is answered with previous literature, research, and existing regulations. Pierce and Turner’s insights on environmental pollution control (1990) as well as Lascoumes and Le Galés’ research on policy instruments implementations effects in societies (2007) provide the theoretical framework that guides this research. I identified (1) community disruption, (2) health and safety concerns, (3) regulatory issues, (4) environmental concerns, and (5) negative effects on animals to be the most prominent themes for objecting to fireworks in consumer-use, with human-related issues in the centre of interest for Finns. From the studied mitigation measures of standards, taxes, prohibition, subsidies, education, and labels and symbols, the combination of standards and education in different forms appear to hold most potential in addressing harm from fireworks. This indicates that regulative instruments are not sufficient alone to prevent fireworks’ harm, but that non-regulative measures, like educational campaigns, are needed as well. My findings also indicate country-specific variations in the motivations for opposing fireworks among the public, as well as among the background reasons that prompt authorities to restrict citizens’ access to and use of fireworks. This suggests that a mix of characteristics, unique to Finland, should be considered when planning for a successful mitigation of harm from consumer-fireworks.
  • Niskanen, Ville-Pekka (2021)
    This Master’s thesis is two-part. The first part is the Methodological Introduction, which introduces the background of this research, the research process, methods and ethical considerations. The second part is a manuscript of a scientific article, sent for review in the scientific journal Sage Open, with the title Wicked problems in Africa – A systematic literature review. The article is a systematic literature review of the usage of Horst W. J. Rittel and Melvin M. Webber’s wicked problems concept in peer-reviewed scientific literature focusing on Africa. The reviewed 45 scientific articles were chosen using a systematic methdolology, basing on a set of inclusion criteria. Based on the reviewed literature, three research questions were answered by utilizing the tabulation of key information from the articles, and with content analysis. The research questions are: 1) What are the main themes and concrete manifestations of issues descri-bed as wicked in the African context? 2) What are the geographic foci of articles that use the concept of wicked problems in the African context? 3) Is the concept of wicked problems utilized and therefore seen as applicable by authors affiliated with African cultures? Based on the reviewed articles, a typology is formed. According to this typology, wicked problems in the African context can be interlinked, exacerbated, or contextual. Especially important is the contextuality, which the concept of dual wickedness reminds us of. In addition, the research states that the lack of usage of the wicked problems concept in scientific literature on Africa may be because of the English-language or Western background of the concept. Based on the results, we suggest, that future characterizations of the wicked problems concept should include context-sensitivity.
  • Lakso, Mea (2022)
    Knowledge co-production has become increasingly popular and even ‘buzzed’ notion in sustainability sciences. It is being applied in various contexts and for myriad of purposes under different, even partially contradicting rationales, yet it is often expected to contribute better to the sustainable transformation of society than normal science. One of the uniting elements in different understandings and applications of ‘knowledge co-production’ is the involvement of the extra-scientific actors in the research process. This implies changes in the conventional roles and relationship between science and society, that raise new questions about the autonomy and accountability of science. This master’s thesis studies knowledge co-production in higher education context and, more specifically, in the case of the HELSUS Co-Creation lab 2019-2020, and critically explores the notion of co-production in sustainability sciences. The dynamics, relationship, and roles between the scientific and extra-scientific actors within the Co-Creation lab are the specific interest in this qualitative case study that is primarily based on 12 semi-structured interviews of the lab participants analyzed by qualitative content analysis. The study shows how the dynamics between the master’s level students and the partners from the private and public sectors had features that resembled to some extent commissioned research type of roles, task coordination and interdependencies, however, it also contained significant characteristics that distinguished it from pure commission type of dynamics, as the autonomy of the student was greater, the control of the partner over the knowledge production process was lesser and the accountability of the students to the partners was more indirect and softer. The similarities between the application of knowledge co-production in the HELSUS Co-Creation lab and the co-production by the logic of accountability are highlighted and critical questions concerning instrumental forms of co-production, logic of accountability, usefulness of knowledge and scientific autonomy are discussed. More critically reflective approaches towards co-production are called for.
  • Rinne, Oula Aleksi Johannes (2022)
    Climate change and biodiversity loss are among the two most serious environmental issues humanity is currently facing. One way of mitigating climate change is to build more wind energy. In Finland, upcoming wind farms are going to increase the national wind energy capacity by almost tenfold. As more wind farms are built, helping in climate change mitigation, the negative biodiversity impacts caused by wind turbines are also increasing. Negative biodiversity effects caused by wind energy include habitat loss, avian mortalities, habitat fragmentation and avoidance behaviour in wildlife. This conflict where two desirable environmental goals have negative counter-effect on each other can be called green-green dilemma. This thesis looks at the biodiversity impacts on habitats caused by wind farms in Finland, and what would be the scale of a habitat tax paid for displacing natural habitat, that would help solve the green-green dilemma. This thesis utilizes geographical information system data of upcoming and in production wind farms and habitats to figure out which habitats are displaced by wind farms in Finland. Also, a wind farm level cost-benefit analysis was done for wind farms in production determine a scale of taxes, which would make 10 % or 25 % of wind farms with lowest net present value compared to habitat impact non-profitable. Two kinds of taxes were considered. Tax based on the quantity of habitat displaced, and a tax based on the quality of habitat displaced. For the determination of the quality of habitat, European red list of habitats was utilized in creation of a prioritization system for different habitats based on their endangerment category. With the prioritization system, each wind farm was given habitat points based on the habitats it was displacing. According to the results of the thesis, wind farms in Finland are mostly displacing woodland habitats. The second most common habitat displaced was marine habitats and the third most common were mires, bogs and fens. According to the prioritization system created for this thesis, most habitats displaced by wind farms are not considered threatened. Still, there should be some consideration about the habitats displaced by wind farms, as minority of habitats were considered threatened according to the prioritization system. Also, we cannot draw too many conclusions about the status of the habitats displaced as the prioritization system has flaws. The two different taxes looked in this thesis both ended up making mostly the same wind farms non-profitable, meaning there were outlier wind farms with low benefits with relatively high habitat impacts. Quantity of habitats-based tax which made 10 % of the wind farms non-profitable was 1.6 million euros per hectare of displaced habitat, and the higher tax rate making 25 % of the wind farms non-profitable was 2.5 million euros per hectare. The habitat quality-based tax was 510,000 € per habitat point for lower rate, and 750,000 € per habitat point for the higher rate. On average, quality tax in Finnish wind farms would be 1.75 million euros with the lower rate per hectare of habitat displaced, and 2.3 million euros per hectare with the higher rate according to the calculations in this thesis. Habitat tax can be one solution for solving the green-green dilemma. Taxes presented in this thesis are considerable higher than habitat restoration costs estimated for Finland, which are approximately between 8000 € and 15000 € per hectare, depending on the habitat restored. Still, a habitat tax needs to be high enough to have an impact on the economic decision making of wind farm developers. If a tax habitat tax would be implemented, it would be best to think about the desired effect of the tax, which will affect the scale of the tax. Also, all kinds of activities displacing natural habitat should be included in the tax, not just displacement caused by wind farms for the tax to be more comprehensive.
  • Tolvanen, Kristiina (2020)
    Ecophysiology and ecology in plants are strongly affected by the conditions surrounding them. Adaptation aids plants to survive and to succeed in the prevailing conditions. Winter is a challenge to plants, particularly in northern latitudes and higher altitudes, because it exposes plants to cold and drought, for example. Plants survive from winter on species level with the help of genetic adaptations and as individuals also with the help of acclimation. Woodland strawberry (Fragaria vesca) has been observed to grow separate winter leaves. This allows it to continue photosynthesis in mild conditions during winter, thus improving its energy balance, and to start growing earlier than other species in the spring, which is beneficial in interspecific competition. Fragaria vesca is a species that has wide distribution in the northern hemisphere, and its genotypes are found from very different locations and conditions. However, adaptive traits such as producing a new set of leaves for winter can turn out to be a disadvantage if environmental conditions change rapidly. Climate change brings about changes that are difficult to predict, and these changes are advancing at a fast pace when compared to the developmental history of plants. The aim of this thesis was to study the effect of temperature on summer and winter leaf development, stolon formation and summer and winter leaf chlorophyll, flavonol and anthocyanin content in different Fragaria vesca genotypes. Leaf chlorophyll and secondary compound content give information about leaf development and stress reactions in plants. Plants are known to produce anthocyanins in order to protect the photosynthetic apparatus during chlorophyll recovery in leaf senescence. Anthocyanins are also produced as a response to low temperatures. Research increases knowledge of the ecophysiological and winter ecology-related processes in Fragaria vesca and in the commercially valuable Rosacea-family as well as provides information about the possible responses of these organisms to climate change. Material for the study consisted of twelve European Fragaria vesca genotypes, which had originally been collected from five countries: Norway, Finland, Germany, Italy and Spain. The genotypes had been collected from different latitudes, and they also expressed altitudinal differences. In this study, these genotypes were kept in two temperature treatments, warm (+16°C) and cold (+11°C/six weeks, after which +6°C/four weeks) at a greenhouse. Leaf development was studied by measuring summer and winter leaf middle leaflet width and length, and petiole length. Stolons from each plant individual were counted on a weekly basis and observations about stolon production in relation to the timing of summer leaf senescence and winter leaf development were made at the same time. Leaf chlorophyll and secondary compound content was measured with a Dualex-meter, which provided values for chlorophyll, flavonol and anthocyanin content. The underlying assumption was that cold temperature would induce winter leaf development and summer leaf senescence. The results show that there were differences in summer leaf size between genotypes. Winter leaves had differences between genotypes, but also within genotypes at different temperature treatments. Stolon count was lower and stolon production ceased slightly earlier in the cold treatment. Moreover, summer leaf chlorophyll content decreased in both treatments, but the summer leaves senesced earlier in the warm room. Summer leaf flavonol and anthocyanin values were generally higher in the cooler temperature treatment. Anthocyanins were also produced by winter leaves in the cooler temperature treatment. Based on the results, Fragaria vesca genotypes had differences related to their origin, but temperature also had an effect on winter leaf development, stolon production and the production of secondary compounds. The effect of cold temperature on the size of developing winter leaves was clear. In the cooler temperature treatment, the winter leaves were smaller than in the warmer treatment. The anthocyanin content of summer leaves was higher than in the winter leaves, and the summer leaf anthocyanin content was higher in the colder temperature treatment, where the stress related to the photosynthetic apparatus and low temperatures was combined. Nevertheless, lower temperature did not explain all the responses observed in the genotypes of the study, and thus it is likely that acclimation and winter leaf development in Fragaria vesca are affected by some other factor in addition to temperature, e.g. light regime. A possible continuation for this work would be to study the effect of light conditions or milder winters on winter leaf development in Fragaria vesca genotypes and on the physiology of the species.
  • Sillantie, Lauri (2012)
    Almost one third of the electrical power manufactured in Finland is made with nuclear power. Running nuclear power plant generates always some radioactive emissions that should be monitored in the vicinities of power plants. This Master's Thesis' aims were to compare Finnish nuclear power plants', Loviisa and Olkiluoto, radiation surveillance programmes with other European programmes and find suggests considering the collected species, frequencies and sample network. Species and sample frequencies in current sampling programmes were evaluated also by the surveillance programmes data collected and analysed between years 2005 and 2010. In this Thesis was also reported could current surveillance programmes species be used as sample species with the new nuclear power plant nuclear monitoring at Pyhäjoki. Also community and ecosystem radiation protection were considered. Swiss, Swedish, German and French radiation surveillance programmes were examined for this work. New sample species were searched from these programmes and also from other sources. The suitability of the suggested species were considered mainly by literature. Species composition at Pyhäjoki was examined from literature. Finnish surveillance programmes are extensive and diverse comparing to programmes in the other countries. Improvement proposals to the sample species and frequencies were nonetheless found. Adequate new species would be at least earthworms, flounder and groundwater. Improvements to the sample frequencies were also suggested and at least mushroom and sediment sampling should be more frequent. Species composition at Pyhäjoki diverse slightly from the species found at Loviisa and Olkiluoto. Based on the literature at least bladder wrack and possibly Common mussel and Baltic tellin are absent from Pyhäjoki. Southern Finland surveillance programmes can still be used as a base for the Pyhäjoki surveillance program and species that are absence just has to be replaced with some similar abundant species. Using the best available knowledge and data collected between years 2005 and 2010 the local population is not exposed to significant amount of nuclear power plant origin radiation. Suggested changes to sample species and sample frequencies would make radiation surveillance programmes even more adequate for monitoring discharges from nuclear power plants. This Master's Thesis will give basic knowledge of the new sample species that would suite to Finnish nuclear power plant radiation surveillance programmes. New species selected from literature should be analysed for radionuclide concentrations before species are added to the sampling programmes. Species composition and quantities at Pyhäjoki should be examined before the final sampling programme is made.
  • Deb, Aruna Rani (2024)
    Since mercury (Hg) may biomagnify in food webs and bioaccumulate in living things, it is considered a dangerous element globally. The two most toxic forms of mercury are methyl mercury (MgHg) and dimethyl mercury (DMgHg). The dietary Hg consumed by fish is mostly removed through the intestine, but some of the MeHg bioaccumulates and is delivered to various organs, such as the liver, kidney, muscle, or gonad. The perch (Perca fluviatilis), the national fish of Finland serves as both a popular food fish and a monitoring species for assessing the chemical health of lakes. Fish tissue exhibits seasonal variations in mercury levels, which are thought to be produced by growth dilution in the summer, which is related to rapid somatic growth during the growing season, and hunger in the winter, which condenses mercury in the muscle as well as during spawning since gonad development requires significant energy expenditure. There has been a considerable study on Hg concentration in fish but currently lack knowledge regarding potential seasonal variation in patterns of Hg content and bioaccumulation to understand the dynamics of Hg content and bioaccumulation. This study investigates (Q1): Does mercury content change in muscle, liver and gonad tissues of males and females of perch over the four seasons? (Q2): How does mercury bioaccumulation change seasonally in different organs between male and female perch? (Q3): How does the mercury content relationship among different organs (muscle, liver, and gonads) vary seasonally and between sexes? Materials were collected monthly from Lake Pääjärvi from April 2020 to March 2021, and categorized into four seasons: winter (January -March), spring (April-Jun), summer (July-September), and autumn (October-December). Each fish was taken of its length, weight, sex, and other tissues too. Total mercury (Hg) concentrations were determined in three organs (muscle, liver and gonad) in male and female perch separately. Using analysis of variance, the annual length-corrected THg content variation and simple linear regression analysis were used to examine the annual THg bioaccumulation variation and to test the relationships in Hg concentrations among three tissues separately in males and females. Seasonal THg levels in female perch significantly varied in muscle and gonads, not in the liver. Females had consistently higher THg in muscle and liver, while males had higher levels in gonads throughout the season. THg bioaccumulation peaked in spring and winter for both sexes in muscle, but lowest in autumn. Liver THg slope was highest in early summer for females and lowest in autumn. Gonads showed the highest slopes in summer for both sexes. The highest slopes between muscle and liver THg for females were in summer and for males in spring. Similar patterns were seen in both muscle-gonad and liver-gonad THg relationships. Female perch showed significant differences only in summer, while in males, the highest slopes were in autumn and lowest in summer. Long-term monitoring is crucial to understanding THg variation in fish.
  • Pankkonen, Pietu (2015)
    Heterotrophic bacteria are essential for carbon cycling in water ecosystems as they bind dissolved organic carbon (DOC) to the biomass and return it to the classical food chain through microbial loop. The treated wastewater from Viikinmäki wastewater treatment plant is discharged to the Gulf of Finland where it increases the quantity of dissolved organic matter (DOM) in the water and furthermore can be an extra energy source for heterotrophic bacteria. There are not yet further studies how the heterotrophic bacteria exploit DOM in the treated wastewater or a monitoring programme for DOC concentrations in the wastewater treatment plants. DOC is the limiting factor for heterotrophic bacteria growth in the Gulf of Finland in the summer. As the bacteria exploit DOC, they consume oxygen and release carbon dioxide. DOM compounds may also diminish light penetration in water which can inhibit the growth and photosynthesis of phytoplankton and macrophytes. The aim of this thesis was to find out 1) the DOC concentrations in the treated wastewater and DOC load in the treated wastewater discharged to the the Gulf of Finland from Viikinmäki wastewater treatment plant, 2) the biodegradability of DOC and DOP in the treated wastewater and 3) how the disc filter about to be used in Viikinmäki wastewater treatment plant affects the quantity and quality of DOC and DOP in the treated wastewater. The DOC load entering the Gulf of Finland with the treated wastewater was quantified by measuring the DOC concentrations in the treated wastewater during the spring and summer 2014. The DOC concentrations correlated positively with chemical oxygen demand (COD) which is regularly measured in wastewater treatment plants. By dividing the COD with 3,66, the DOC concentrations were successfully estimated for a longer period. In order to evaluate the biological degradability of DOC and DOP in the wastewater effluent, treated wastewater was incubated (+15 °C) for two months with surface water heterotrophic bacteria from the Gulf of Finland and changes in DOC concentrations, the biological oxygen demand and nitrogen and phosphorus concentrations were measured. Furthermore the heterotrophic bacteria were incubated for one month in disc filtered wastewater effluent and also in regularly treated wastewater to find out the effect of the new filter on DOM quantity and quality. The yearly DOC load from Viikinmäki wastewater treatment plant to the Gulf of Finland was estimated to be about 1460 tons which is approximately one fifth of the annual DOC load from River Vantaanjoki. The ratio between DOC and COD concentrations calculated here can only be used to quantify the amount of DOC load from Viikinmäki wastewater treatment plant and similar ratio must be calculated individually for every point source. The biodegradability of DOC in the treated wastewater was equally low to the biodegradability of DOC in River Vantaanjoki. The quantity of DOC bound to the bacterial biomass was rather low and the amount of DOC lost via respiration was relatively high. Accordingly the DOC in Viikinmäki wastewater effluent does not become efficiently available to higher trophic levels. The disc filter has the potential to remove DOC and DOP from treated wastewater which would decrease the DOC and DOP load significantly in the Gulf of Finland. The disc filter decreased DOC concentrations 14 % in comparison to regularly treated wastewater. The disc filter didn't affect the quality of DOC, i.e. there was no difference in the biological degradability of DOC between the two wastewater treatment processes. However the disc filter was possibly able to remove the biologically available part of DOP from treated wastewater but the issue still needs further investigation.
  • Koskela, Lotta (2004)
    This research examines the environmental attitudes of the employees in the City of Tampere. This research is one of the goals in the city’s environmental strategy in 2003 and it is made for the environmental protection department of City of Tampere. The purpose of this study was to find out the environmental attitudes of the employees in the City of Tampere, the behaviour related to the attitudes and the relationship between the attitudes and the behaviour. The results will be utilized when planning the environmental work of the city. The theoretical frame structure in this study is based on the Theory of Planned Behaviour and it is applied to fit for the research. The Theory of Planned Behaviour is used a lot in the attitude-behaviour studies. There is a one-component model of the attitudes in the background of this theory. In this study the examination of the environmental attitudes is based on the one-component model. In the examination of the relationship between attitudes and behaviour the whole Theory of Planned Behaviour is used instead. A term ‘free rider behaviour’ is also included in the theoretical frame structure although it will not be studied with any special questions. Quantitative methods were used in this research. The research was conducted through a mail survey study to 1000 employees in the beginning of June 2003. 462 people out of 1000 returned the questionnaire. The results showed that the employees consider concern about the environment in Tampere well-founded. Trashing and littering in a public place or in the nature worries the employees by far the most. The second most worrying thing is the pollution of the air and water. They are also worried about the destruction of the constructed environment for example culturally valuable buildings and places. Concern is clearly higher among women than among men. The employees in the City of Tampere believe in their own possibilities to influence the state of the environment. Environmentally friendly behaviour is seen important although other people would not behave at the same way. Majority of the employees support the intervention of the society with limitations and by far more than half of the employees support different kinds of payments and taxes that advance the sale of environmentally friendly products. These results also show some kind of readiness to lower the standard of living. The employees think that conservation of the environment is important and its position in the society’s decision-making should be strengthened. Despite of the employees’ environmentally friendly opinions, even two out of three employees admit that they are able to behave more environmentally friendly than they do now if they just want to. The employees for example sort and recycle their waste well, but the behaviour in regard to consumption and commuting has a lot to improve.
  • Huovelin, Suvi (2019)
    Citizen science is a research method in which data collection, analysis or other stages of research is distributed to a large number of volunteers. Citizen science enables collection of large-scale data. In addition, in few cases Citizen science has been integrated into formal school education. It has been found to attract students' interest in the subject and research and to teach students about scientific research. However, the real benefits of citizen science for schools have been just scarcely studied. This study explored the experiences of middle school and high school students on the Helsinki Urban Rat Project (Kaupunkirottatutkimus). The research questions were: (1) How do the middle school and high school students who participated in the Urban Rat Project experience citizen science as part of biology teaching? (2.) How do the students who participated in the Urban Rat Project feel about urban rats and how does the Project affect students’ perception of rats? The data was collected by group theme interviews from middle school and high school students who participated in the City Rat Project. The data consisted of nine recorded interviews with a total of 29 interviewees. The interviews were transcribed and analyzed by content analysis. The Urban Rat Project aroused situational interest towards urban rats and research project. Main factors for aroused interest were novelty and specialty of the project, the involvement created by hands-on activities and the meaningfulness created by contextualism of an authentic research. Learning experiences were categorized by Bloom’s revised taxonomy and the results revealed a number of knowledge types and cognitive process categories, suggesting that the project developed a diverse range of students' thinking. Students were able to develop deeper research skills, critically explore research and its outcomes, and learn about practical challenges and constraints of scientific research. Urban rats gave rise to both negative, positive and neutral feelings among students. The negative emotions were caused by a variety of causes, such as the appearance and behavior of rats, culture created attitudes and students own experiences. Positive feelings were caused by interest toward rats and good experiences with pets. The knowledge learned in the study about urban rats generally reduced negative feelings and in one case aroused them, but many interviewees also felt that the study had no effect on their attitude towards rats, because interaction with rats was not concrete enough during the project and the students were disappointed that they did not see rats or rat footprints. The authentic research context of citizen science such as Urban Rat Project can increase meaningfulness to studying biology, which is not necessarily achieved by other teaching methods and may teach the realities of scientific research better than traditional practical work. In addition, citizen science can provide knowledge and nature experiences that allow learners to reflect on their relationship with nature. In order to achieve nature-related learning goals of the school education, citizen science projects should pay particular attention to the concreteness of the interaction between learners and nature and to the students' experiences in nature during citizen science.
  • Kettunen, Paavo (2023)
    Education for sustainability has come to be seen as an important part of achieving the sustainability goals, also in universities. However, the challenge for sustainability education is that sustainability is an ever-changing and highly complex concept. One theoretical approach for studying the learning of such complex concepts and phenomena is the conceptual change research tradition. The theory of conceptual change stems from the constructivist approach to learning, according to which learning takes place by modifying and completing existing knowledge structures. Sometimes these prior knowledge structures of the learner conflict with scientific knowledge, and in order to reach a new understanding, the learner has to change and reorganize their existing conceptions. With a new conception comes a whole new way of understanding a phenomenon, as related concepts take on new meanings. The process described above is called conceptual change. This thesis studied what kind of conceptions university students had about sustainability before the University of Helsinki's Sustainability Course (SUST-001, 3 cr) in autumn 2021, and how these conceptions had changed after the course. In addition, we investigated whether there were differences between students in human and natural science-oriented disciplines in the above-mentioned aspects. Conceptions were investigated using a baseline and endline measurement design. The study sample was students enrolled in a sustainability course at the University of Helsinki (N = 109). The data was analyzed both qualitatively and quantitatively. Based on the results, the students' perceptions were quite narrow at the beginning of the course, although the responses showed that most students came to the course with some prior knowledge of sustainability. In addition, three narrow conceptions similar to misconceptions of the conceptual change were identified from the initial survey: ecology-limited, anthropocentric and weak sustainability conceptions. In the final measurement, students' perceptions of sustainability improved and, in particular, students' understanding of the different dimensions of sustainability, the interlinkages between them and the complex nature of sustainability in general increased. About half of the narrow conceptions also changed, although the anthropocentric conception was slightly more persistent. In the cross-disciplinary analysis, attention was drawn to the tendency of students in natural science-oriented disciplines to change their narrow view in comparison to students in human science-oriented disciplines. Based on the results, the Sustainability course can be seen as successful in teaching many of the key contents of the concept of sustainability. There were also indications of conceptual change. However, there is a need to further develop the course and to integrate sustainability more broadly into the different educational programs. Furthermore, it is very important to continue to study the success of this integration and of sustainability education also in the future.