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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.

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.

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.

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.

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.

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.

The present climate crisis demands an energy transition, where development in renewable energy is significant. The shift has brought about a surge is wind power schemes underpinned by considerable political conditions. More and more wind power takes place on Sámi homeland, Sápmi. The thesis studies the argumentative performance of the Sámi participating in an operational licensing process of a wind power scheme, Davvi vindkraftverk. The objective of the research has been to demonstrate what an empirical case discloses about argumentation of the Sámi regarding wind power resistance. Few research has addressed political opposition and resistance of wind power in Sápmi. Moreover, the thesis politicises and complexifies the ecological approach to wind power in applying a critical political ecology framework, serving for the exploration of the argumentative performance of the Sámi with an explicit consideration to power within the licensing process. Public hearing statements are a requisite measure of an operational licensing process as well as the most important avenue for discussing viewpoints of stakeholders. A data corpus of 35 hearing statements representative of the Sámi has been systematically treated with an inductive open coding following a robust and rigorous thematic analysis. The analysis has proposed a set of five thematic categories of basis of argumentation: statutory basis, complex harm, advice, asymmetries, and land conceptualisations. The findings suggest that argumentative performance of the Sámi is limited to acting in structures and procedures designed, constructed, and executed by the regnant society. A concept of “rules of the game” is introduced referring to the type of language, rhetoric, and comprehensively, argumentation that ought to be used in hearing statements by the Sámi. The thesis argues that Sámi seek to employ pragmatic adjustments to argumentation on a basis that is apt for discourses of rational, capitalist land-use and land allocation to better navigate participation in the wind power licensing process and to legitimise agency for decision-making. Yet, argumentation is performed strategically without giving away the positionality of being in resistance. The thesis contributes to critical political ecology research suggesting that climate change mitigation and energy transition measures are influenced by relations of power. Additionally, the findings could guide licensing processes into less destructive and dichotomous character, orienting future measures of climate change mitigation and energy transition towards more inclusive decision-making, giving ground for a more holistic understanding of land-use conflicts regarding wind power on Indigenous territory and adding to overcoming contrasting onto-epistemologies. To conclude, the findings of the thesis point to a pressing need for more detailed research on trajectories of green infrastructure on Indigenous territory. What is more, future research could re-disclose Davvi vindkraftverk, when a final verdict of the operational licensing process is known.

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.

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.

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.