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Browsing by study line "Ympäristömuutos"

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  • Tuomaala, Emilia (2022)
    Permafrost peatlands have a significant role in the global carbon cycle, as they store ca. 185 Pg of carbon. Because of the slow decomposition of organic matter, they have sequestered carbon dioxide from the atmosphere and cooled the climate for thousands of years. However, in anaerobic decomposition also methane – a strong greenhouse gas – is produced. Climate change results in changes in permafrost peatland habitats; distribution and proportional share and these changes also affect the CO2 and CH4 fluxes. In this master’s thesis I compare the net ecosystem exchange and pore water methane concentrations in different microhabitats in the Stordalen palsa mire in Abisko, Sweden. In addition, I review the reported climate change-driven habitat changes in the area and its effects on the CO2 and CH4 fluxes. My results suggest that Sphagnum sp. and Sphagnum fuscum -microhabitats were net sinks of CO2 whereas lichen-, shrub- and Eriophorum-microhabitats were net sources. These results were best explained by the proportional coverage of green vegetation, which was highest in both Sphagnum-microhabitats. No discernible differences were found between pore water methane concentrations in different habitats. Permafrost thawing has increased the occurrence of wet habitats in Stordalen. These habitat changes have increased carbon sequestration in the area but at the same time methane emissions have also increased. Because of this, the radiative forcing of the peatland has changed from negative to positive and the on-going habitat changes will likely continue in future. On a longer timespan though, the radiative forcing will likely switch back to negative as carbon sequestration increases and the effects of the methane emissions decrease.
  • Norontaus, Maija (2022)
    Mercury is a toxic heavy metal that ends up in aquatic ecosystems both as atmospheric deposition as well as from the catchment area surrounding the water body. Under the right circumstances, inorganic mercury can be methylated into methylmercury, which accumulates in organisms and food webs and is harmful to humans and animals. Humans are exposed to methylmercury mainly through consumed fish as almost all the total mercury content in fish muscle consist of methylmercury. Mercury content of fish is affected by numerous different factors, such as the food consumed by the fish, the characteristics of the fish species and fish individual, level of lake eutrophication, mercury concentration in water and catchment area. Thesis studies total mercury content and mercury bioaccumulation in cyprinid fish. The species included in the study are roach (Rutilus rutilus), bream (Abramis brama), bleak (Alburnus alburnus), white bream (Blicca bjoerkna), blue bream (Ballerus ballerus), ide (Leuciscus idus), tench (Tinca tinca), rudd (Scardinius erythrophthalmus) and crucian carp (Carassius carassius). Three main research questions were: (1) Can diet of different cyprinid fish explain the mercury content? (2) Is mercury content consistent between fish species in different lake types, or does lake type affect mercury content? (3) Is mercury bioaccumulation consistently similar between fish species between lake types? The fish samples for this study were gathered prior to MSc during July-August in 2020 and 2021 from Kukkia, Hauhonselkä and Pääjärvi, which are classified as mesotrophic lakes, and from eutrophic Vesijärvi, Tuusulanjärvi and Hulausjärvi. Total length, weight, sex, sexual maturity, condition factor (K), fish diet and muscle total mercury content were determined from each fish. The diet of the fish and the differences in the total mercury content were tested with analysis of variance. Mercury bioaccumulation was tested with using linear regression analysis and the slope coefficient obtained from the regression equation was tested for bleak and roach with t-test. From the abundant species of the study the highest length corrected (to length 16.6 cm) mercury contents were measured in bleak and roach, while the contents were lower in white bream and bream. The mercury content differed most clearly in species whose feeding behaviour was very specialized. For example, the differences in mercury contents between bleak, which mainly consumes surface insects and zooplankton, and bream, which prefers benthic food, were clear in every lake studied. Mercury contents were mainly higher in mesotrophic lakes compared to eutrophic lakes, but results varied by species. In addition to fish diet and lake type, fish’s metabolism, growth rate and life cycle length probably influenced the species-specific mercury contents. When comparing the abundant species, the bioaccumulation of mercury was steepest in bleak and roach. Compared to these species’ bioaccumulation was slower in white bream and bream. When comparing mercury bioaccumulation within species between different lake types, the differences were species-specific. For example, the bioaccumulation of bleak was consistently steeper in mesotrophic lakes compared to eutrophic lakes, but the bioaccumulation of white bream was steeper in eutrophic lakes. Based on this study, it can be concluded that mercury content and bioaccumulation in cyprinid fish were influenced by e.g., species-specific characteristics, fish diet and level of the lake productivity. In addition to these factors, mercury content and bioaccumulation of fish may have been affected by the land use of the lake catchment area, as well as the anoxic areas of the lakes, which are propitious places for methylation. This study provided valid information on which factors may be relevant for cyprinid fish when observing their mercury content and bioaccumulation.
  • Kivisaari, Kiira (2022)
    Environmental sustainability and environmentally responsible management have found their way as discussion topics in the Finnish contemporary art field. The contemporary art event Helsinki Biennial chose to make environmental sustainability as one of their corner stones of producing the event (Taskinen et al 2021). In this master’s thesis I assess the environmental responsibility of Helsinki Biennial and how its environmental actions reflect on the expectations of the contemporary art field in Finland from a managerial perspective. The research was conducted through autoethnographic and content analysis methods. This research will try to answer three questions 1. What environmental actions were taken and how were they selected? (R1) 2. How do the environmental action taken compare to the current expectations of environmentally responsible management in the Finnish contemporary art field? (R2) I am also interested in finding out 3. What types of hopes and concerns about future work are identified by Helsinki Biennial organizers and other experts in the Finnish contemporary art field? (R3) The results show that Helsinki Biennial compared well on the expectations of the field. Based on the answers of the interviewees, there is a lot of potential and moti-vation within the field which waits to be unleashed, for example through new financ-ing and travel policies and by increasing the knowledge and time resource of em-ployees. This study also found out about the future visions regarding environmental matters within the contemporary art field.
  • Kuru, Saarajohanna (2023)
    Lichens are sensitive organisms widely used for environmental biomonitoring. Urban environments have been under heavy pollution, especially sulphur dioxide and nitrogen oxides, due to human activity which has led to the disappearance of lichens in city centres. Regulations and technological changes have led to cleaner air and less deposition of pollutants, especially sulphur dioxide on the vegetation in both rural and urban areas. This in turn has led to recolonization of lichens in former lichen deserted areas. In this study epiphytic macrolichens on park maples were surveyed using simple tree-based random sampling in three parks in Helsinki, and in one park in Loviisa, Siuntio and Raasepori each. The sampling and surveying methods were selected based on the SFS standard “Ambient air. Biomonitoring with lichens. Assessing epiphytic lichen diversity”. Species identification took place on site and in Botanical museum (Finnish Museum of Natural History). The results from parks in Helsinki were used to estimate if lichens have recolonized the trees. In addition, the results from the other Uusimaa municipalities were used to assess how different is the lichen species assemblage when comparing the relatively more polluted region of Helsinki to the less polluted regions in Uusimaa. The study found that pollution levels in Helsinki have declined enough to enable recolonization, of which there have been signs already in 1990s and 2000. The study used lichen diversity value of defined functional groups as one of the statistical methods which gave new information about how the species tolerance or sensitivity to pollutants shapes the recolonization. Comparison between the study areas in Uusimaa region revealed that concentrations of nitrogen oxides steer lichen species assemblage in Helsinki. Lichen surveys in Helsinki are scarce. This study brings topical information about the lichen situation in Helsinki, and it uses an as yet relatively unknown method to extract information from lichen assemblage. Regular, comparable lichen surveys are needed to further research the pressure that human activities cause on urban nature. Such time series would help to monitor both the urban nature loss and the impact of climate change on the urban nature.
  • Järvinen, Riikka (2022)
    Urban greenspaces are valuable resources for humans and are an integral part of the urban landscape. They are also popular sites for various social and cultural activities, such as dog walking. Dog ownership rates are increasing globally at a rapid rate, hence increasing the dog populations within urban cities. The increasing number of dogs could potentially have negative consequences to the quality of urban parks. Furthermore, there is a lack of research on the impacts of dogs on urban environments. The aim of this study is to gain a better understanding of the impacts of dogs on path-side soils in urban greenspaces. Soil samples were collected from both Helsinki and Lahti. The impact of dog urine was studied by comparing path-side soil samples between areas with high dog activity (i.e., parks) and similar areas with low to no dog activity (i.e., cemeteries). Soil samples were collected three times during the growing season in 2021 at three different treatments: close by 1) an evergreen tree, 2) a lamppost, and 3) a lawn area. The samples were analyzed for soil pH, electrical conductivity, organic matter, soil moisture, NO3--N, and NH4+-N. Net N mineralization and net nitrification rates were also calculated. The results indicated that dog urine is a significant contributor to the input of nitrogen in urban parks. Soil NO3-N and NH4+-N concentrations were significantly higher in parks than in cemeteries and exhibited clear seasonal trends. Soil pH was generally lower and electrical conductivity higher in parks than in cemeteries. Poles and trees exhibited the greatest concentrations, suggesting that the impact of dog urine is highly localized around path-side objects. None of the treatments in cemeteries showed little to no changes throughout the growing season. Lastly, the net nitrification rates were significantly higher in parks during spring and summer. In contrast, net mineralization rates were generally higher in cemeteries than parks. These results confirm that urban planners need to take into consideration the impact of dogs to mitigate any potential negative consequences to the quality of urban parks.
  • Berglund, Nora (2022)
    In Finland and in many other European countries, indoor housing of dairy cattle has been increasing at the expense of grazing. According to Finnish legislation, only dairy cows housed in tie-stalls are obligated to graze for 60 days per year between May and September. Pressure to intensify production leads to increase in herd sizes, regional concentration, lack of suitable pastureland near large barns, and automation of milking. Conversely, grazing is regarded as important for animal welfare, maintenance of biodiversity and cultural landscapes. Farmer perceptions towards grazing have not been studied in Finland comprehensively, which need to be understood better in order to provide adequate support for sustainable management of grazing. The research aims at gaining understanding of the external and internal factors driv- ing the farm-level decision making related to grazing regimes. Concept of good farming ideal is used to examine farmers’ decision-making. The data was collected from 26 cattle farms with a gradient of grazing from zero to maximum. Firstly, an online questionnaire was sent out to farmers and secondly, semi-structured inter- views were conducted with 7 dairy producers, to further explore farmer views about grazing, biodiversity, and animal welfare. The results show farmers who practice grazing to perceive it more positively than the farmers who do not graze. Some of the farmers who grazed seemed to consider it almost as an intrinsic value, whereas farmers with no grazing saw it as an inef- ficient production method, which they were afraid would become an obligation. The most im- portant internal factors driving decision-making about grazing based on the questionnaire and interviews, were animal welfare, decreased workload because of grazing, infrastructure of the farm, economic aspects, and benefits of grazing to biodiversity and landscape values. Exter- nal factors found to affect the decision of grazing were incentives, regulations, and consumer expectations. Animal welfare was found to be a basis for production for many and the most important feature valued for good farming, to which grazing was seen to contribute. The re- sults imply subsidies regarding grazing should be higher for grazing to be considered profita- ble and more enjoyable by farmers.
  • Tikka, Suvi (2022)
    Biohiilet ovat biomassasta pyrolysoitua hiilirikasta materiaalia. Biohiiliä voidaan käyttää maanparannukseen sekä maan hiilivarastojen kasvattamiseen ilmastonmuutoksen hillitsemiseksi. Biohiilet ovat rakenteeltaan erittäin pysyviä ja voivat pysyä maassa satoja tai jopa tuhansia vuosia. Tietoa biohiilen pitkäaikaisvaikutuksista boreaalisessa ilmastossa on kuitenkin vielä hyvin vähän. Tässä peltotutkimuksessa tarkasteltiin havupuubiohiilen vaikutuksia hiilirikkaassa peltomaassa yhdeksän vuotta biohiilen lisäyksen jälkeen. Biohiilen lisäystasoja 5 tai 10 t/ha vertailtiin yhdessä mineraalilannoituksen tasojen kanssa. Biohiilen lisäys nosti maan hiili/typpi-suhdetta sekä maan magnesium- ja natriumpitoisuuksia. Biohiili ei vaikuttanut maamurujen kestävyyteen, maaperän kosteuspitoisuuteen, maan hiilipitoisuuteen tai ohran satobiomassaan. Biohiilellä ja lannoituksella ei havaittu merkitseviä yhteisvaikutuksia, lukuun ottamatta kahta mittausviikkoa, jolloin biohiili tasasi lannoitustasojen välillä olevia eroja maan kosteudessa. Biohiilen vähäiset vaikutukset maassa johtuivat todennäköisesti sen kulkeutumisesta syvemmälle maahan. Tutkimusruutujen maa oli lisäksi hyvärakenteista, multavaa ja ravinteikasta peltomaata, jossa biohiilien vaikutukset eivät tule helposti näkyviin. Puubiohiilellä ei havaittu olevan negatiivisia vaikutuksia maahan, joten se on turvallinen tapa nostaa maan hiilivarastoja pohjoisissa olosuhteissa. Biohiilten pitkäaikaisvaikutuksista boreaalisella peltomaalla tarvitaan lisää tietoa.
  • Ahonen, Veronica (2019)
    Permafrost peatlands have the capacity to store significant amounts of carbon, and thus they act as important controllers of the climate. Approximately 14% of the world’s soil organic carbon pool is stored in permafrost peatlands, which are sensitive to climatic fluctuations due to their location in the high latitudes of the subarctic zone. Permafrost peatlands also act as a habitat for a large number of moisture-sensitive organisms, such as bryophytes and testate amoebae, which can be used to study how the hydrology of peatlands has changed and will continue to change throughout time, giving us an opportunity to predict the future of peatlands under a changing climate. In this Master’s Thesis I examined the testate amoebae composition and used these species as indicators to study hydrological fluctuations from three subarctic permafrost peatland cores extracted from Taavavuoma and Abisko in northern Sweden. The species compositions were combined with radiocarbon (14C) and lead (210Pb) dates to reconstruct the past water table levels for the late Holocene, spanning four climatic periods. The reconstructions were then compared to past studies on testate amoebae to understand how permafrost peatlands and their species assemblages respond to changes in the hydrology of the active layer of the peat. Out of the study sites only the Taavavuoma cores spanned the Dark Age Cold Period (DACP) and Medieval Climate Anomaly (MCA). Species compositions in both cores indicated fluctuating water tables during the DACP, but during the MCA the results began to contradict with one site showing a wetter, and the other a drier MCA. Two out of three study sites indicated a wetter Little Ice Age and a drier Post-Industrial Warming, supporting past studies indicating similar results, whereas one study site gave opposite results. The results indicated large variability in testate amoebae assemblages throughout time, indicating that the hydrology of peatlands can change very abruptly and vary considerably even on a local scale. Modelling is however complicated by the poorly known ecology of testate amoebae, which is why a multi-proxy approach is essential to reliably predict the future fate of permafrost peatlands.
  • Boxström, Agneta (2021)
    Abstract: Northern boreal peatlands form one of the biggest carbon pools in the biosphere, thus having great potential to cause major changes to the global carbon cycle. The ongoing recent warming may affect the carbon dynamics though factors, such as, vegetation, hydrology and permafrost balance. As the future is still uncertain there are no definitive answers on how the peatlands will react in the future. Fortunately, moisture sensitive organisms such as, bryophytes and testate amoeba is preserved in the peat and can therefore be used to reconstruct past climatic shifts. In this thesis I studied palaeohydrology and peat accumulation over the last two millennia, from three peat cores originating in a permafrost peatland in Rogovaya, Russia. I used testate amoeba as a proxy of past moisture conditions and plotted the taxa composition of each core against 14C and 210Pb dated samples, to reconstruct past moisture shifts. The results were also supplemented by plant macrofossil and carbon accumulation data for more robust results. Of the three cores, Rog11 provided the oldest testate amoeba dataset by reaching the Dark Ages Cold Period. During this period there were indications of dry moisture conditions followed by a wet Medieval Warm Period. The Little Ice Age gave indications of a drying trend, while toward the end of the LIA Rog8 indicated opposite moisture conditions. From the end of the LIA onwards a general trend of drying and increased carbon accumulated is noted. Yet, during the last decade the trend has turned. The wet shift might indicate that the threshold for the peatland has been reached and the amount of melting permafrost has exceeded the evapotranspiration rate. As a conclusion my result indicates that the dynamics of both hydrology and carbon are complicated processes affected by both autogenic and allogenic factors, therefore causing large variability even on a local scale. The absence of widely spread observations of the most recent wet shift also indicates that the response of the peatland to the recent warming might be unequal. To rectify this situation, continued research is crucial, so that we can increase our understanding of climate-peatland interactions.
  • Keränen, Fanny (2021)
    This study aimed to identify conservation landscapes with potential to be mutually beneficial for people and African savanna elephants (Loxodonta africana) in South Africa through spatial conservation planning analyses that integrate ecological and socioeconomic data. The research questions were: (i) what are the most ecologically suitable areas for the reintroduction of elephants, and (ii) which of these areas provide the best opportunities for also sustaining socioeconomic development of local people. The first question was answered with an ecological model that predicts habitat suitability for elephants, developed by a combination of literature review, expert opinion, and GIS-based methods. The second question was answered by combining the ecological model with socioeconomic criteria in Zonation spatial conservation planning software. The results show that the central part of South Africa holds most potential for elephant conservation as it has the largest uniform area of high-quality habitat, while the area also meets the socioeconomic criteria. The priority areas for the conservation of elephants were classified into top priority classes of 1%, 2%, 5%, 10% and 20%. The identified areas hold an unrealized opportunity in the wildlife and ecotourism sectors, and the reintroduction of elephants to those areas could provide the foundation for long-term economic activity of local communities e.g. in the form of elephant-based ecotourism, while contributing to the conservation of elephants. Conserving just the top 5% priority areas would grow South African protected area estate by approximately three million hectares and increase the current elephant range by approximately 75%. Ideally, the results of this study could be used to inform the on-going decision-making process on where to allocate resources for elephant conservation in South Africa.
  • Kavanagh, Kayleigh C (2022)
    Urban densification is resulting in the rapid loss of urban green spaces and their associated values. Moreover, the remaining urban green spaces are under increasing pressure to meet diverse resident needs and preferences. While past studies have investigated the intrinsic, instrumental, and relational values associated with such spaces, little attention has been paid to the sub-sets of relational values referred to a fundamental-relational (i.e., contributions toward enhanced social resilience) and eudemonic-relational values (i.e., actions, experiences, and habits linked to a “good life”). This study used public participation geographic information systems (PPGIS) surveys in a residential neighborhood of Helsinki, Finland to spatially explore and examine the differences between intrinsic, instrumental, fundamental-relational, and eudemonic-relational values in urban green spaces. I analyzed responses from residents and stakeholders (n = 1089) using Chi-square tests for significant associations and density-based clustering. Mapped values indicated that green spaces were primarily valued for their relational value, with an emphasis on eudemonic-relational values. Moreover, there were differences in the spatial distribution of instrumental, intrinsic, and relational values between green space types and values were spatially clustered by land use. Notably, there were few differences in how these values were assigned by different sociodemographic groups. I discuss the implications of these findings for local- and city-scale planning and the use of value typologies in PPGIS surveys. Further research in this field will benefit from the use of further value subcategories, increased geographic scale, and additional study of the influence of sociodemographic factors.
  • Oikarinen, Kaisa (2022)
    Tässä tutkimuksessa selvitettiin, millaisia kehyksiä ilmastoahdistus saa kahdeksassa, vuonna 2021 julkaistussa suomalaisessa podcast-jaksossa. Näin pyritään lisäämään ymmärrystä ilmastoahdistuksen ilmiöstä, sekä siitä, millaisia kehystyksiä aihe mediassa saa. Tutkimus on tehty laadullisella kehysanalyysilla, joka perustuu Erwin Goffmanin (1974) kehittämään kehysteoriaan ja sen myöhempiin sovellutuksiin. Lyhyesti sanottuna, tutkimus pohjaa siihen olettamukseen, jossa median tavat kehystää ja esittää jokin aihe tai asia ohjaavat sitä, millä tavalla asiat meille esitetään ja millaisina me asiat näemme. Tutkimuksen aineisto kerättiin suoratoistopalvelu Spotifysta, Yle Areenasta ja Suplasta. Kehyksien muodostamisessa hyödynnettiin Robert Entmanin (1993) median kehysanalyysin periaatetta, jossa kehyksillä on neljä tarkoitusta: Ongelmien määritteleminen, ongelman aiheuttavien tekijöiden tunnistaminen, moraalisten arvioiden tekeminen sekä ratkaisujen ehdottaminen. Tutkimuksen tuloksena syntyi kolme kehystä, jotka nimettiin luonnollisen ilmastoahdistuksen, ilmastoahdistus sukupolvikysymyksenä sekä ilmastoahdistus tarvitsee vertaistukea, käsittelyä ja toimintaa kehyksiksi. Jokainen kehys kuvaa omalla tavallaan sitä, millaisena ilmastoahdistus nähdään viime aikaisissa podcast-keskusteluissa. Luonnollisen ilmastoahdistuksen kehyksessä korostuvat näkemykset siitä, kuinka ilmastoahdistus voidaan nähdä luonnollisena ja normaalina, sekä hyvänä reaktiona motivoivan vaikutuksensa kautta. Kaiken kaikkiaan kehys kuvaa ilmasto- ja ympäristöahdistuksen ilmiön monitahoisuutta ja yksilöllisyyttä, sekä pyrkii vahvistamaan näkemyksiä siitä, mitä ilmastoahdistus on ja mitä se ei ole. Lisäksi ilmastoahdistuksen sisältämä ahdistus sana kyseenalaistetaan. Ilmastoahdistus sukupolvikysymyksenä - kehys avaa puolestaan näkemyksiä nuorten ilmastoahdistuksen syihin ja korostumiseen, sekä ottaa kantaa aikaisempaan ilmastoahdistuskeskusteluun, joka joidenkin keskustelijoiden mielestä näyttäytyi ilmiötä vähättelevänä. Kokonaisuudessaan kehyksessä kuitenkin korostuu näkemys siitä, että ilmastoahdistus ei ole vain nuoria koskettava asia, vaikka se tällä hetkellä korostuu ja ilmenee eniten nuoremmissa sukupolvissa. Kehys ilmastoahdistus tarvitsee vertaistukea, käsittelyä ja toimintaa, tuo esiin keskustelijoiden näkemyksiä ja kokemuksia liittyen ilmastoahdistuksen käsittelyyn ja lievittämiseen, sekä osallistuu keskusteluun koskien ilmastotekojen merkityksellisyyttä. Tutkimuksen tulosten perusteella voidaan sanoa, että ilmastoahdistus saa vuonna 2021 julkaistuissa, suomalaisissa podcastkeskusteluissa monia eri sävyjä ja ilmastoahdistusta käsitellään niissä laajasti. Ja vaikka keskustelijoiden näkemykset ovat pitkälti linjassa ilmastoahdistusta käsittelevien julkaisujen kanssa, muutamia kiinnostavia ja tutkimattomiakin näkökulmia ja kehystyksiä ilmenee. Osaltaan tutkimuksen tulokset täydentävät kuvaa siitä, miten valtavirtamediaa hitaammat lajityypit – kuten podcastit – mukautuvat muualla esitettyihin määritelmiin ja kehystyksiin, mutta myös täydentävät niitä. Tällöin podcast-keskustelujen voidaan nähdä tarjoavan vaihtoehtoisia kehyksiä, jotka osittain haastavat ja täydentävät julkisuudessa hallitsevia kehyksiä.
  • Kangas, Jonna (2022)
    Climate change is expected to cause salinity change in the Baltic Sea and therefore may affect organisms living in the Baltic such as plankton. The microbial loop is an important part of the plankton food web. It consists of heterotrophic bacteria, nanoflagellates and ciliates and is connected with the classic plankton food chain through interactions with primary producers and mesozooplankton. Therefore, salinity affects the functioning of the microbial food web not only directly, but also through salinity induced changes on primary producers and mesozooplankton. In this master’s thesis I studied the effects of salinity change on microbial loop components bacteria, nanoflagellates and ciliates in an outdoor mesocosm experiment containing four salinity treatments with salinities of 3.5, 5.5, 7.5 and 9.5, three replicas each. The experiment took place offshore at the Tvärminne Zoological Station. Bacteria were sampled from the mesocosms every other day and nanoflagellates and ciliates every 6th day. Bacteria were analysed with the flow cytometer, nanoflagellates with epifluorescent microscopy and ciliates using an inverted microscope. The effects of salinity on microbial loop components were statistically tested using linear mixed effects models. Results of the experiment show that salinity had an indirect effect on microbial loop components through changes in mesozooplankton composition. There were significant differences between high and low salinity treatments in bacteria abundance and composition, the interaction strength between HNFs and bacteria and in the mean cell size of ciliate communities. These were mainly caused by differences in mesozooplankton community structure between salinity treatments, which had cascading effects on the strength of top-down and bottom-up control on the trophic levels of the microbial loop, leading to changes in bacteria abundances and composition. Based on the results of this thesis, more studies are needed to detect the effects that changes in the composition and functioning of the microbial loop might have on the ecosystem. Further research should also focus on the significance of the structure and diversity of the communities within the microbial loop as well as the functional roles of different species in the microbial food web.
  • Keinänen, Milka (2020)
    High Nature Value (HNV) farming systems hold significant natural values but have decreased drastically during the process of agricultural modernization. Biodiversity in Europe is dependent on these extensively farmed areas because they maintain habitats for many endangered species; e.g. 30% of Europe's butterfly species have declining populations and most live in natural and semi-natural habitats. European common agricultural policy (CAP) favour conventional agriculture, leading HNV agriculture in a foul position. HNV areas are often abandoned or replaced with intensive farming practices. Participatory agricultural innovation processes offer solutions to the distress of HNV farmlands. In these processes different actors – such as farmers, entrepreneurs, advisors, NGO and municipality representatives – are brought together to find localized solutions to the challenges of the area. HNV-Link project was active during years 2016-2019 identifying, developing and improving innovations in ten European HNV farming areas. In this thesis I examine the success of innovations in seven Learning Areas (LA) in terms of socio-economic viability, environmental conservation and cultural region. The data in this thesis is both quantitative and qualitative. I use mixed methods- approach where the statistical analysis and qualitative content analysis support each other. I carried out a survey for the LA coordinators where they responded how was the impact of the innovations to social, economic and environmental wellbeing. I complement the survey with data gathered by the project in 2016-2017. I conduct a qualitative content analysis to innovation fiches using Atlas.ti programme and a statistical analysis with IMB SPSS statistics programme with non-parametric tests. I compare the relation of socio-economic and environmental impact of the innovations, explicit aim of HNV conservation, recognition of environmental topics in the fiches and cultural region. Innovations were successful both socio-economically and environmentally. There was a possible synergy between economic and environmental impacts, which indicates economic viability of the LA’s improving HNV conservation. Innovations with explicit HNV conservation objective had more positive environmental impact than the ones without. Innovations with high recognition of environmental themes in fiches had slightly more positive environmental impact, but the difference was so weak that they fail to express the environmental outcomes reported in the survey. Congruent patterns didn’t occur inside cultural regions which might be due to the similarities of the areas or small sample size. The results display the inherent unpredictability of innovation processes, and the importance of holistic understanding and long-term monitoring of them.
  • Winquist, Emelie (2021)
    The heath vegetation in the Jauristunturit study area is highly affected by the reindeer fence that was built in the mid-1950s between Finland and Norway, to prevent summer grazing in the Norwegian side. In the study area, the Finnish and Norwegian pastures are used during different seasons, causing differences in reindeer grazing history, and with time differences in vegetation. Additionally, local topography also impacts the vegetation composition and structure creating variation in local vegetation patterns. My research questions are: How vegetation patterns differ between summer- and winter- grazed areas, and which plant functional groups have the most significant difference? How local topography affects vegetation patterns, and does the effect of topography differ between summer and winter pastures? The data was collected from five 400 m long transects that crossed the fence and had vegetation plots with 10-m intervals. The %-cover and height of each vascular plant, bryophyte, and lichen species were estimated from 0.25 m2 plots. Later, species data was grouped into functional groups and general linear models were used to analyze differences in cover, height, species number, biomass, and leaf-area indices between countries. Topography indices were calculated in GIS for each plot and analyzed with random forest models to find out the most important topography indices explaining vegetation patterns. The vegetation data was collected by four teams, and therefore, the comparability in the collected data between teams was analyzed. Significant vegetation differences were found in the ground layer, with higher cover and biomass of bryophytes on the Finnish side (mean biomass 168.2 vs. 65.2 g m-2). Reindeer lichens were more abundant on the Norwegian side (mean biomass 197.0 vs. 2.9 g m-2) which is visible in aerial and satellite images and in the field. Among vascular plants, evergreen dwarf shrubs had higher biomass and leaf area index on the Finnish side and dwarf birch had higher cover and height on the Norwegian side. Topography indices had a higher level of variance explained on the Norwegian side, and higher at the ground layer compared to vascular plants. Elevation had the greatest impact on vegetation, and after that, topography protection index for 50 m and depth to water stream network for 2 and 10 ha. The differences between data collectors were not considered to have a major impact on the results. The results indicate that there are significant differences in vegetation between summer- and winter-grazed areas, mainly in the ground layer, and most differences are caused by differences in reindeer grazing history, but also local topography has an impact.
  • Escanciano Gomez, Alfredo (2022)
    The Baltic Sea is undergoing changes due to climate change, including an increase in its temperature. This may in turn lead to changes in the traits of the species that inhabit it, including non-endemic, invasive species. Palaemon elegans is a species native to the Atlantic Ocean that has been present in the Baltic Sea since the beginning of this century. Abilities such as high thermal tolerance make it successful in colonising new ecosystems like the brackish waters of this sea. However, less is known about the behavioural traits’ adaptions to these changes. This study aims then to find out how climate change may affect the behaviour of this species. To do so, five behaviours expressed by this species were observed and analysed to see how temperature change, seabed composition and body size influence their expression. The behaviours analysed were aggressiveness, movement frequency, reaction to food stimulus, number of feeding interactions and shelter-seeking. Analyses were conducted using ten-minute videos with ten specimens of P. elegans placed in water tanks and interacting in ecosystems representations with elements typical of the seabed where this species lives, both vegetation and rocks. Student's t-tests in R were then performed to test the significance of possible differences between the behaviours studied and the three parameters that may influence their expression. The results obtained show that the increase in water temperature might indeed lead to an increase in the frequency of the five behaviours studied except in aggressiveness. On the other hand, it was found that the composition of the ecosystem does not have a significant influence overall, while body size has a major influence on feeding related behaviours. Therefore,knowing more about changes in the behavior of species susceptible to climate change can be helpful to understand how biodiversity and its distribution will vary in the not so distant and changing future and what consequences it may generate at the ecosystem level.
  • Eerola, Emmi (2021)
    Kaikkien lauhkealla vyöhykkeellä elävien eliöiden täytyy sopeutua ympäristöolosuhteiden suureen vaihteluun vuodenaikojen mukaan. Vuodenaikaan liittyviin muutoksiin kuuluvat muun muassa lämpötilan ja valoisuuden vaihtelut, jotka ovat selkeitä myös järvissä veden alla. Lämpötilan, ravinteiden ja valon määrät vaikuttavat järven tuottavuuteen ja siten moniin muihin tekijöihin, myös kalojen ravinnon määrään. Eri kalalajit ovat sopeutuneet erilaisiin olosuhteisiin, joissa ne pärjäävät parhaiten, ja jokaisella lajilla on oma optimilämpötilansa. Kalat ovat aktiivisimmillaan niille sopivien olosuhteiden aikaan, mikä useimmilla lajeilla on kesä, jolloin ravintoakin on saatavilla enemmän. Suurin osa kalatutkimuksista tehdään yleensä kesällä avoveden aikaan, koska se on helpompaa ja talvella kalojen ei ajatella olevan tutkimuksen arvoisia. Suuri osa maailman järvistä kuitenkin on jääpeitteen alla osan vuodesta ja talvi on iso osa kalojen elämää, minkä vuoksi niiden tutkiminen vuoden ympäri on tärkeää. Tämän tutkimuksen neljä pääkysymystä olivat: 1. Millä tavalla eri kalalajien, lahkojen, sekä lämpötila- ja ravintokiltojen osuudet saaliista muuttuvat eri vuodenaikoina? 2. Kuinka paljon yksikkösaalis muuttuu vuoden aikana? 3. Miten kalojen koko ja kuntokerroin muuttuvat vuoden aikana? 4. Mitkä eri ympäristö- ja biologiset tekijät selittävät yksikkösaaliin muutoksia? Koekalastusta tehtiin vuosina 2020-2021 vuoden ajan koekalastusverkkosarjalla kolmessa habitaatissa: litoraalissa, profundaalissa ja pelagiaalissa. Joka kuukausi kalastettiin vähintään kolmen päivän ajan. Jokaiselle saadulle kalalle määritettiin laji, pituus, paino ja kuntokerroin ja jokaiselle yksittäiselle pyyntikerralle laskettiin yksikkösaalis. Kalastuksen lisäksi Pääjärvestä otettiin joka kuukausi fysikaaliskemiallisia mittauksia. Koekalastuksen tulosten mukaan selvästi runsain kala Pääjärvessä oli särki, toiseksi runsain kala oli kappalemääränä ahven ja biomassana kuha. Talvea kohti särjen ja ahvenen määrät laskivat, kun taas kuhan, kiisken ja mateen osuudet saaliista nousivat. Selvästi runsain kalalahko vuoden kokonaissaaliissa oli karppikalat, vaikka ahvenkalat olikin runsain lahko loppukesällä ja lopputalvella. Lämpimänveden kaloja oli muita lämpötilakiltoja enemmän koko vuoden saaliissa, vain helmikuussa viileänveden kaloja oli enemmän, kun kiiski oli kuukauden runsain kala. Petokalojen kappalemääräosuus saaliista oli jokaisena kuukautena muita ravintokiltoja pienempi, mutta talvella petokalojen biomassaosuus saaliista oli suurin. Yksikkösaalis oli alhaisimmillaan jääpeitteisinä kuukausina ja suurimmillaan kesällä. Kalojen keskikoko oli talvella kesää suurempi ja kuntokerroin alhaisempi. Kappaleyksikkösaaliin muutoksia eniten selittivät kuntokerroin, lämpötila, typpipitoisuus ja pH, kun taas biomassayksikkösaaliin muutoksia eniten selittivät kuntokerroin, lumensyvyys, lämpötila ja kokonaishiili. Pääjärven kalayhteisön rakenteessa tapahtui muutoksia vuodenaikojen välillä. Selkein muutos oli yksikkösaaliin muutos kesän ja talven välillä. Pääjärven lisäksi ympärivuotista kalatutkimusta pitäisi tehdä morfologisilta ja fysikaaliskemiallisilta piirteiltään erilaisissa järvissä, jotta saataisiin tietoa, miten kalayhteisö reagoi eri vuodenaikoihin eri olosuhteissa.
  • Sarajärvi, Aija (2021)
    Climate change is one of the biggest global threats. Food production is one of the most significant sources of greenhouse gas emissions. It has been estimated that food systems account for 19 – 29 % of anthropogenic greenhouse gas emissions. Many studies have shown that products of animal origin cause more environmentally harmful emissions than plant-based products. In order to reach the 1,5 degree target, diets need to become more sustainable and more plant-based. The life cycle of food is being studied more today to identify their climate and environmental impact. The purpose of this study was to determine life cycle assessment of a plant-based protein product. The life cycle assessment started with the initial production and ended with the finished product in the factory. The study did not take into account the transport of products to stores and consumer activities. The study examined six different scenarios, which were e.g. dealing with the conversion of mixed electricity to wind power and the impact of the new alternative packaging on the results. The study was made by openLCA and the databases used Ecoinvent 3 and AGRIBYLASE 3.0. Life cycle assessment was examined using the ReCiPe 2016 Midpoint (H). The impact categories were global warming, land use, water consumption and freshwater eutrophication. According to this study, converting mixed electricity to wind power can reduce greenhouse gas emissions by 49 – 50 %. Converting electricity to wind also significantly reduces land use, water consumption and freshwater eutrophication. Greenhouse gas emissions and phosphorous emissions of plant-based protein are lower than animal origin products. Packaging materials accounted for 7 to 13 % of greenhouse gas emissions. Based on this study, it is recommended to change the primary electric source to wind power.
  • Tuomimaa, Julia (2020)
    Climate change has exacerbated extreme weather events. According to climate scenarios, temperatures will rise and heat periods will become more common also in Finland. These heat periods worsen the urban heat island phenomenon which is known to have negative impacts on human well-being. The impacts of the urban heat island phenomenon can be reduced through careful urban planning, adaptation policies and economic investments. Adaptation to climate change can be monitored through indicators but research and development on adaptation indicators has been largely absent. The development of adaptation monitoring indicators is particularly important in order to ensure the long-term success of the city's adaptation efforts and whether adaptation is moving towards the desired goals. This thesis asks the following research question with the help of a literature review, a focus group discussion and a questionnaire: what kind of indicators can be used to monitor and evaluate adaptation to the urban heat island phenomenon in Helsinki? With the help of the literature review and New York Climate Change Panels framework “the seven steps to indicator selection”, 17 preliminary indicators were developed which were divided into six themes accounting the diverse nature of the urban heat island and its impacts. The indicators were specified in a focus group discussion which had six attendees from environment-, the technical-, social- and health sectors. After the group discussion, the indicators were further modified with the help of a questionnaire answered by ten municipal employees, mainly from the environmental, technical and social and health sectors. On average, respondents found each indicator useful, five indicators were found to be really useful on average, and three indicators were found to be useless among a couple of respondents. After the survey, 11 indicators were modified and one indicator was removed. The end result was 16 indicators for monitoring adaptation to the urban heat island phenomenon divided into the following themes: social vulnerability, state of environment, infrastructure, green-blue infrastructure, policy actions and communication. The development of indicators does not as such contribute to the development of urban adaptation to a desired level, but it is nevertheless an important step in the process of developing adaptation monitoring in the city of Helsinki. This work provides tools for the city to develop their adaptation monitoring strategy which should be systematic and comparable. If the city wants to develop its adaptation monitoring, it is essential to document decisions and programs to explore sufficient coverage. Decisions and programs should be compared against identified adaptation commitments, targets and needs. As a conclusion, this thesis is important step towards more diverse and effective adaptation monitoring. This thesis takes adaptation monitoring forward, developing ways to put adaptation monitoring into practice.
  • Nikkola, Henna (2021)
    Ilmastonmuutos lisää sään ääri-ilmiöitä kuten mittavia rankkasateita, jolloin myös hulevedet, eli rakennettujen alueiden pinnoille kertyvät sade- ja sulamisvedet, muuttuvat yhä akuutimmaksi ongelmaksi. Yksi tiivistyvien kaupunkien haasteista on hulevesien hallinta. Hulevesiä hallitaan pääasiassa niin kutsutuin perinteisin menetelmin, eli pääasiassa viemäröiden, mutta sen rinnalle on nousemassa niin kutsuttu luonnonmukainen hulevesien hallinta. Luonnonmukaiset menetelmät hyödyntävät luonnon omia prosesseja, ja ne voivat parantaa hulevesien laatua, pienentää virtaamahuippuja, edistää luonnon monimuotoisuutta ja tarjota virkistyshyötyjä. Hulevesien hallinnan ja luontoarvojen huomioiminen kaupunkisuunnittelussa ei ole yksinkertaista - suunnittelussa on huomioitava monenlaisia tavoitteita, joiden yhteensovittamisessa kohdataan ristiriitoja. Ristiriidat voivat paljastaa tavoitteiden taustalla olevia arvoja, ja siten kertoa, minkälaista kaupunkia todellisuudessa toteutamme. Tutkielma toteutettiin osana HELSUS Co-Creation Labia ja yhteistyökumppanina toimi Helsingin kaupunki. Tutkielman tavoitteena oli luontoarvojen ja hulevesien hallinnan huomioimisen selvittäminen ja kaupunkisuunnittelijoiden agentuurin kartoittaminen Helsingin maankäytön suunnittelussa. Tutkielmassa pyrittiin vastaamaan seuraaviin tutkimuskysymyksiin: 1) Millaisia asioita asemakaavoitusvaiheessa mukana olleet Helsingin kaupungin työntekijät mielsivät kuuluvan luontoarvojen pariin? 2) Miten luontoarvot ja hulevesien hallinta huomioitiin projekteissa? 3) Mitä asioita suunnittelijat kokivat keskeisinä luontoarvojen ja luonnonmukaisen hallinnan huomioimiseksi suunnitteluprosessissa yksilön osalta? 4) Mitkä asiat vaikeuttivat luontoarvojen huomioimista tai suojelua ja luonnonmukaisen hallinnan toteuttamista? Tutkielma tehtiin käyttäen eksploratiivisen ja välineellisen tapaustutkimuksen menetelmiä. Aineistona toimi pääasiassa seitsemän Helsingin kaupunkisuunnittelijan haastattelut, joille tehtiin temaattinen analyysi. Tutkielman kohteena oli Helsingin kaupungin hulevesien hallintaa koskeva suunnittelu/päätöksenteko asemakaavoitusprosessissa. Yksittäiset tapaukset olivat asemakaavaprojekteja Helsingin Kaarelan, Laajasalon ja Lauttasaaren kaupunginosista. Teoreettisena viitekehyksenä tutkielmassa hyödynnettiin pääasiassa arvojen, sääntöjen ja tiedon muodostamaa viitekehystä päätöksentekokontekstissa. Aineiston perusteella luontoarvojen ja luonnonmukaisen hulevesien hallinnan huomioimisen kanssa kilpailevia arvoja ja intressejä olivat tekninen toimivuus ja käytännöllisyys, ihmisten turvallisuus, esteettisyys, taloudellinen kestävyys, asuntotuotanto, rakentamisen tehokkuus, tietämättömyys/osaamattomuus, harrastusmahdollisuudet sekä liikenneratkaisut. Yleisesti kaiken kiteyttävänä haasteena oli tilan puute. Vaikka päätavoitteet ja lopulliset päätökset arvoineen tulevat poliittisilta toimijoilta, niin voidaan kuitenkin sanoa, että suunnittelijoilla on mahdollisuuksia toteuttaa omia arvojaan työssään ja säännöissä on jonkin verran niin sanotusti pelivaraa. Suunnittelussa on suunnittelijakohtaisia eroja esimerkiksi siinä, kuinka aktiivisesti ja minkälaisella asenteella kukin huomioi ja edistää luontoarvoja ja hulevesien hallintaa suunnitteluprosessissa. Hulevesien hallinta vaikuttaa Helsingissä olevan murrosvaiheessa kohti vihreämpään infrastruktuuriin nojaavaa suunnittelua. Sitä vauhdittaakseen kaupungin kannattanee lisätä pilottiprojekteja, suunnitella pilottikirjastoa, lisätä työvoimaa ja kuntien välistä yhteistyötä sekä varmistaa, että suunnittelijoilla on tarpeelliset tiedot ja työkalut, joita myös osataan hyödyntää. Tarve jatkotutkimusten tekemiselle löytyy kaupunkisuunnittelussa kilpailevien arvojen ja intressien selvittämisestä ja niiden tunnistamisesta suunnitteluprosessissa ja päätöksenteossa.