Browsing by study line "Miljöförändring"

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.

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.

Phosphorus loading through agricultural runoff and erosion induce eutrophication in waterbodies. Weather conditions outside the growing season are major drivers for phosphorus loss from agricultural fields. Overwinter cover crops are utilized to prevent phosphorus and nitrogen nutrient loading and to gain other benefits, such as increased soil organic carbon content and microbial diversity and improved soil structure. However, vegetation can release easily soluble phosphorus after exposure to freeze-thaw cycles (FTC) and, therefore, increase the amount of phosphorus entering waterways. Different species respond to FTC with varying intensity, making some species more preferable for overwinter vegetation cover. The objective of this study was to determine FTC effect on twelve different cover crop species’ shoot-induced phosphorus runoff risk and cover crops’ effect on soil phosphorus runoff risk after FTC with and without P-fertilization. Cover crop species, field mustard (Brassica rapa), oil radish (Raphanus sativus), Italian ryegrass (Lolium multiflorum), rye (Secale cereale), tall fescue (Festuca arundinacea), timothy (Phleum pratense), hairy vetch (Vicia villosa), honey clover (Melilotus albus), red clover (Trifolium pratense), white clover (Trifolium repens), buckwheat (Fagopyrum esculentum) and lacy phacelia (Phacelia tanacetifolia), were grown in a greenhouse after which half of the replicate pots were exposed to FTC consisting of 6 cycles (-2°C for 24 h, 4°C for 24 h). One extreme freeze-thaw event was added by freezing the shoot and soil samples (-20°C) after sampling. Compared to bare soil, presence of cover crops and different cover crop species did not affect freezing-induced phosphorus runoff risk in soil indicated by soil easily soluble phosphorus concentration. FTC increased shoot-induced phosphorus runoff risk, indicated by shoot water-extractable phosphorus concentration, in all cover crops, except for P-fertilized lacy phacelia. Based on estimated field scale shoot water-extractable phosphorus pools, buckwheat had greatest risk for shoot-induced phosphorus runoff after FTC. The cover crop species with lowest shoot-induced phosphorus runoff risk following FTC were tall fescue and honey clover. P-fertilization had only minor effect on CC shoot- and soil-induced overwinter phosphorus runoff risk. The results of this study can be used for planning cover crop cultivation for overwinter vegetation cover in agricultural fields located near waterways where loss of dissolved phosphorus is significant concern.

Achieving the global 1,5 degrees Celsius climate target requires the contributions of several societal actors to reduce emissions. Several actors have started to work to untangle the emissions of their operations and abate them. The Turku and Kaarina parish union, which operates in Southwest Finland, has also set a personal goal to reduce its emissions, aiming to be a carbon-neutral organization by 2029. The purpose of this thesis is to find out the carbon footprint and the forests’ carbon sinks of Turku and Kaarina parish union and make the carbon neutrality roadmap with some examples of how to achieve the parish union’s carbon neutrality goal of 2029. In addition, the thesis examines through the selected case study the organization’s methodology of the carbon footprint and the realization of the carbon neutrality goals. Both the parish union’s carbon footprint and the forests’ carbon sinks are calculated for the year 2022. The materials of carbon footprint consist of the activity data of the parish union and the emission factors. The calculation of the carbon footprint is carried out based on the international standards, Greenhouse Gas Protocol, and ISO 14046. The forests’ carbon sinks are calculated based on the parish union’s information on its forestry management of 2022 and the research of Natural Resources Institute Finland about the carbon sinks and stocks of local parishes of the Evangelical Lutheran Church of Finland of 2021. The estimate of gross emissions of Turku and Kaarina parish union for 2022 is approximately 4985 tCO2e. The biggest emission groups are procurements, real estate, and travel. The size of the forests’ carbon sinks is approximately 1176 tCO2e, offsetting about 24–29 % of the gross emissions depending on the parish union’s carbon neutrality targets. Based on the union’s carbon neutrality goal, the net emissions should still be reduced by about 2261 tCO2e and offset by about 551 tCO2e. The realization of Turku and Kaarina parish union’s carbon neutrality goal would require significant emission reductions, especially from the biggest emission groups. Because the union has already executed a major portion of the easiest emission reductions of the union’s operations, the realization of new and large emission reductions is challenging to implement only in six or seven years. In addition, the realization of the carbon neutrality goal is hampered for instance the different limitations and uncertainties related to the carbon footprint calculation, stability of forests’ carbon sinks, and the practical implementation of the roadmap. However, the carbon neutrality goal of the Turku and Kaarina parish union will be progressing particularly with the successfully implemented sustainability transformation and transition and the Church’s environment diploma, supporting the Church’s environmental education, and promoting wide-scale societal transformation towards the climate-neutral life.

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.

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.

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.

Peatlands are a significant carbon and nitrogen reservoirs, making them potential sources of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions. Variations in water table level change the oxygen content of peat, affecting the oxidation-reduction or redox state of the peat, which is known to influence the biochemical processes and thus greenhouse gas (GHG) emissions. The aim of this study was to assess the effect of controlled anoxic redox conditions and inorganic electron acceptors (TEAs) on redox potential (Eh), and N2O, CH4, and CO2 emissions. In this study during an anaerobic incubation experiment, the rates of formation of these GHGs and Eh values as a function of time were measured from drained (D) and undrained (UD) peat of three nutrient levels: mesotrophic (ME), oligotrophic (OL), and ombrotrophic (OM). Redox conditions were controlled to three levels by nitrate (NO3-), ferric iron (Fe3+), and sulphate (SO42-). In addition, measurements were performed on untreated (Ctrl) peat. The peat was in an anoxic state throughout the incubation (Eh < 300 mV) and the values were in the order of TEA reduction, even though they were mainly in the iron and manganese reduction zones, probably due to the naturally high iron content of the peat. As expected, N2O formation was highest in flasks with added NO3-, and N2O formation was weak and ceased without addition. CH4 formation was reduced in flasks with added NO3- or SO42-, and SO42- addition also inhibited CO2 formation on which NO3- addition had no effect. In contrast, the addition of Fe3+ increased both CO2 and CH4 formation compared to Ctrl treatment, and it is possible that methanogens were involved in the reduction of Fe3+. In Ctrl flask, the redox state did not decrease to the lowest level compared to the other treatments as expected, but the Ctrl treated UD ME peat had the highest CH4 formation at the end of incubation. For all treatments, GHG emissions were higher from nutrient-rich peat in the descending order ME > OL > OM. In general, UD peat also had higher gas formation than D peat. All GHGs were formed the most while Eh values were around 0 mV and the value was especially high for CH4 formation, probably due to the linkage between methanogens and iron. The poor ability of the Pt electrode to detect NO3- or oxygen was the most likely reason for the variable and low Eh values of the flasks with NO3- addition. For the same reason, oxygen leakage of the anaerobic chamber was most likely responsible for the varying Eh values measured from Ctrl treated OM peat. This study suggests that Eh measurement is a useful predictor of the redox state and reactions, but it must be considered together with other measurements and analyses such as microbial analysis, nutrient analysis, and GHG measurements to predict redox processes and GHG emissions in anaerobic peatland. In particular, the role of iron on CH4 emissions requires further research.

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.

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.