Browsing by discipline "Maantiede"

This paper studies discourses about suburbs that occur in newspaper writings about 1960s and 1970s infill development. The study aims to find out how writings about infill development are structured in the local newspaper Helsingin Sanomat between 2000 and 2016. The objective is to discover how a high-rise suburb appears as a site for infill development, and what kinds of discourses appear in newspaper writings about infill development. The paper uses discourse analysis to examine how high-rise suburbs built in 1960-1970 are discussed in Helsingin Sanomat between 2000 and 2016, using writings about infill development in Helsingin Sanomat in that period as research material. Due to the choice of newspaper, the addressed suburbs are found in the Helsinki metropolitan area. In recent years, Finnish urbanization has led to regional economic marginalization, which in the Helsinki metropolitan area is concentrated in the high-rise suburbs of the 1960s and 1970s. In addition to economic marginalization, these suburbs are seen to suffer from decreasing and aging population, and a need for renovations. The stated aims of infill development include urban unification and social diversification of the suburbs in order to prevent the cycle of economic marginalization. Combined with deterioration of apartments built in the 1960s and 1970s, structural and social problems in high-rise suburbs have led to a societally challenging situation. The writings contained four discourses about suburbs: potential of the suburbs, defense of the suburbs, the suburb as problematic, and the suburb as a conflict-prone site for infill development. The most powerful discourse was about potential. The defense discourse emphasized the uniqueness and meaningfulness of the suburb as the environment and home of its inhabitants. The conflict discourse refers to writings where the suburb is seen as an infill development site that causes conflict. While most of the newspaper writings mention the age and deterioration of the period’s suburbs, the problem discourse did not dominate the research material. Based on the research, the ways of talking about the suburb depend on the speaker, the speaker’s motives, and the subject. The discourses allowed a crucial observation that the suburb is an arena for wielding power where a contradictory and naïve attitude towards developing suburban social life is a major problem slowing down the prevention of economic marginalization. Because the suburbs of the Helsinki metropolitan area are very different, the research doesn’t reveal what suburbs are really like. Instead, the research shows how the suburbs of the metropolitan area appear in the context of writings about infill development, and reveals the persons featured in writings about infill development as well as the suburbs that are interesting to the media. The study also examines how different parties react to infill development, and seeks to shed light on the motives behind the remarks of different parties.

Plant-plant interactions, i.e. biotic interactions, shape plant communities and the vegetation's succession along abiotic environmental factors. Positive interactions (e.g. facilitation) may expand species niches and enhance growth and reproduction. Negative interactions (e.g. competition, allelopathy) can interfere with growth and reproduction, even out competing some species from their niches. Negative and positive interactions co-occur, but research has shown that positive interactions are generally more common and important than negative ones in harsh environments. The theory of change of net-interaction from negative to positive along an environmental gradient is called the stress gradient hypothesis (=SGH). This work examines nordic crowberry's (Empetrum nigrum ssp. hermaphroditum) effect on arctic-alpine species' sexual reproduction under different environmental stress levels. Crowberry is a dominant species in low-nutrient, acidic arctic-alpine ecosystems. Its competitive ability is based on allelopathic characteristics and a forming of dense mats. It is also unpalatable for herbivores. The species facilitative characteristics include providing shelter from the wind and maintaining an ericoidmycorrhiza community. In this research environmental stress is represented by geomorphological disturbance and soil moisture, with the interactions between crowberry and other species are examined as the relationship between crowberry cover and the fitness measures (e.g. abundance of flowers or fruits) of study species. Explanation for the variation in the effects of crowberry is tried to find from the traits of the study species. Data was collected in May 2011 from Kilpisjärvi, northernmost Finland. The study area comprised 960 1m2 cells. In each cell the cover of each species (including crowberry), the abundance of each species flowers or fruits, the cover of geomorfological disturbance and soil moisture were recorded. Generalized linear models (=GLM) were run for all species to identify the best model for predicting fitness (as selected by the AIC-criterion). Spatial autocorrelation was accounted for by repeating analyses using generalized estimation equation models (GEE), which explicitly account for the spatial structure of data. 17 species were included to the research based on the abundance of their flowers and berries in the research area. Crowberry is included in the best fit model for 14 out of 17 species. The effect of crowberry was positive for four species and negative for ten species based on the modeling results. Interactions of the crowberry and one of the environmental variables are included to the models 19 times. In ten of these cases the interactions agreed with the predictions of the SGH (i.e. effect of crowberry became less negative with increasing abiotic stress). No species traits were consistently related to the outcome of interaction between crowberry and environmental variable, although crowberry effects on dwarf shrub species appeared to be more commonly positive than on other growthforms. According to these results, crowberry has dominant role in arctic-alpine plant communities. The species effect on sexual reproduction of other plant species is commonly negative, but the effect can change to positive along environmental stress gradients, supporting the SGH. Dwarf shrubs may interact positively with crowberry because of sharing the same mycorrhiza type, while more generally species may benefit from crowberry due to its provisioning of shelter from the wind and increased soil moisture. The negative effect of crowberry might be related to its production of allelopathic compounds or its dense growth. The reason for crowberry having a facilitative affect under disturbed conditions might be an indirect effect of disturbance decreasing crowberry's allelopathic effects. These results show that the roles of crowberry and biotic interactions in arctic-alpine vegetation are important. Therefore understanding their effects and mechanisms is important in predicting how this vegetation will respond to changing climate.

Land use practices are changing at a fast pace in the tropics. In sub-Saharan Africa forests, woodlands and bushlands are being transformed for agricultural use to produce food for the rapidly growing population. Although food production is crucial for the survivability of the people the uncontrolled expansion of agricultural land at the expanse of natural habitats may in the longer term decrease food production due to disturbances in water balance, increased land erosion and eradication of natural habitats for pollinators. Before the impacts of land use/land cover changes on the ecosystem can be studied the study area needs to be mapped. The study area of this thesis is located in the Taita Hills, Kenya. In previous studies the land use/land cover was mapped on higher hierarchical level in classes such as agricultural land, forest and bushland. In this thesis high spatial and spectral resolution AisaEAGLE imaging spectroscopy data was used to map the common agricultural crops found in the study area. Ground reference data was collected from 5 study plots located in the study area. Over 50 plant species were mapped but only 7 of these were used in the classification. The AisaEAGLE data was acquired in January–February of 2012 and was radiometrically, geometrically and atmospherically corrected. Minimum noise fraction (MNF) transformation was applied to the data to reduce the noise and the dimensionality. Optimal number of MNF bands was defined based on analysis of the information content of the bands. The classification was done with support vector machine (SVM) algorithm using radial basis function (RBF) kernel. Gamma, penalty and probability threshold parameters for the classifier were defined based on analysis of different combinations of these values. The analysis showed that gamma and penalty values had only minor impacts on the classification result. Based on the analysis an optimal threshold level was defined where pixels that were not likely to belong to any of the classes were left unclassified while maximum number of the known targets were correctly classified. Study area was classified with the optimal threshold value 0.90. Classification with threshold value 0.00 was done for reference. The overall accuracies for the classified pixels were 91.52% and 99.70% for the classifications done with probability threshold values 0.00 and 0.90. As the threshold was increased to 0.90 61% of the pixels were left unclassified. At the optimal threshold level between classes misclassifications were almost completely removed whereas the total number of correctly classified testing samples decreased. Applying MNF transformation to the data before the classification increased the overall accuracy from 80.58% to 91.52% while other parameters stayed the same. Results of this thesis showed that SVM classifier used with MNF transformation yielded high overall accuracies for the crop classifications. Adjusting the probability threshold to an optimal level was important since the study area was heterogeneous and only fraction the species were classified. For further applications the possibilities of object-based classification should be considered. The results of this thesis will be shared with the Climate Change Impacts on Ecosystem Services and Food Security in Eastern Africa (CHIESA) –project.

Kawah Ijen is the picturesque crater of the Ijen volcano located in Eastern Java, Indonesia. However, it is not just any volcano crater, as it happens to be the locus of labour-intensive sulphur mining operation. Each day up to 15 tons of sulphur is extracted from the Ijen crater by the 350 men working as manual miners. These men carry even 100 kilogram loads of sulphur out from the crater with bare brawn and the work is with no doubt burdensome. Kawah Ijen's natural beauty has also caught the interest of tourists', and the crater has become commodified as a tourism destination, visited by hundreds of international tourists each day. Thus the storyline of this master's thesis is two-fold. The first research objective scrutinizes the Kawah Ijen sulphur mine from a commodity chain perspective, emphasizing the tough work the sulphur miners have to bear in order to satisfy the needs of the consumers at the end of the chain. The second, and the essential objective of this research in turn interrogates how the presence of the sulphur miners has become also an inevitable part of the Kawah Ijen tourism experience. In this the aspiration is to elucidate how the sulphur miners have become aestheticized as a Global South tourism attraction. In other words, this research aims to interrogate the peculiarity of this reality, by exploring how both trade and culture, and human and commodity mobilities are entangled and enshrouded within the crater of the Ijen volcano. In human geography, a research framework of 'Follow the thing' has been adopted by scholars in order to study the geographically far-flung production chains of consumer goods. As a framework it aims to make critical political-economic connections between the consumers and distant, and often also underprivileged, producers. In this Marxist-influenced undertaking emphasis is placed particularly on commodity fetishism. This notion has been mobilized to illuminate how consumers have become alienated from the means of production, in their symbolically-laden everyday consumption. As sulphur is a raw material needed in the production processes of many goods such as white sugar, fertilizers, medicines, and rubber, this research shows how these commodities were 'followed' into their origins to this particular sulphur mine. During a period of field work, a method of participant observation was utilized to get contextual understanding of this production site. The initial research objective is therefore to make connections and create awareness of the inequalities within commodity production networks. In the final research objective of this master's thesis, a postcolonial approach is mobilized to critically interrogate this initial setting, in which the miners are seen as poor and stagnant producers. Thus the Kawah Ijen tourists are taken under lens in order to gain understanding of this touristic encounter nuanced with cross-cultural and socio-economic differences between the tourists and the miners. Therefore the setting of Kawah Ijen will not only be observed as a place of production, but also as a site - and object - of consumption. By analysing blogged travel stories written by the tourists themselves, this research aims to illuminate what the tourism experience of the Kawah Ijen is about in the realm of consumption. Special attention is given to how the encounter with sulphur miners has become a constitutive part of the adventurous and authentic tourism experience of Kawah Ijen. The blog post analysis on the Kawah Ijen tourism narrative shows how the imaginaries of the sulphur miner as the 'Other' are adhered to, as the tourists construct their travel identities, make meaning of their experiences and finally represent their experience to the outside world. Finally this research aims to make ruptures to Global South fetishism by elucidating how the Kawah Ijen sulphur mine has become both commoditized and fetishized in its own right. In this fetishzation process the sulphur miners are depicted as poor and primitive, which as categories act as symbols for authentic tourism consumption in the social frameworks of the tourists. However, the aim is not to demonize the tourists, but to give recognition to the nuanced personal and social realities they are embedded in their consumption. Hence, the tourism experience of Kawah Ijen is constructed through a point of view more sensitive to the subjective negotiation of authenticity. It is argued that the Kawah Ijen tourism experience is a process in which the meaning of the experience is negotiated in a wider framework, which is vicariously embedded in postcolonial discourse. Finally, it is concluded that although there is some unequal power relations at presence in the tourism consumption of Kawah Ijen, the tourism can be the means to make more sustainable living for the miners. The leapfrog from the mining to tourism has to be only carried out in a deliberate way with respect to all of the stakeholders.

The purpose of this Master's thesis was to create a new model for screening possible optimal locations for utility-scale solar power plants (i.e. solar parks, solar power stations and solar farms) in larger city areas. The model can be used as a part of a decision making when examining site potentiality in a particular city of interest. The model includes forecasts for the year 2040. The main questions of the thesis are as follows: 1) What are the main criteria for a good location for a utility-scale solar power plant and 2) how to build a geographic information system (GIS) model for solar power plant location optimization? Solar power plants provide an alternative to producing renewable energy due to the enormous distribution potential of solar energy. A disadvantage of utility-scale solar energy production is the fact that it requires larger areas of land than the more traditional power plants. Converting land to solar farms might threaten both rich biodiversity and food production, which is why these factors are included in the model. In this study, methods from the field of geographic information science were applied to quantitative location optimization. Spatial analytics and geostatistics, which are effective tools to narrow down optimal geographical areas, were applied for finding optimal locations for solar power plants, especially in larger city regions. The model was developed by an iterative approach. The resulting model was tested in Harare (Zimbabwe), Denver (United States) and Helsinki (Finland). The optimization model is based on three raster datasets that are integrated through overlay analysis. The first one contains spatial solar radiation estimates for each month separately and is derived from a digital elevation model and monthly cloud cover estimates. The resulting radiation estimates are the core factor in estimating energy production. The second and the third dataset are two separate global datasets, which were used to deal with land use pressure issues. The first of these is a hierarchically classified land systems model based on land cover and intensiveness of agriculture and livestock, while the second is a nature conservation prioritization dataset, which shows the most important areas for conserving threatened vertebrate species. The integration of these datasets aims to facilitate smart and responsible land use planning and sustainability while providing information to support profitable investments. The model is based on tools implemented in the ArcGIS 10 software. The Area solar radiation tool was used for calculating the global and direct radiation for each month separately on clear sky conditions. An estimate of the monthly cloud coverage was calculated from 30 years' empirical cloud data using a probability mapping technique. To produce the actual radiation estimates, the clear sky radiation estimates were improved using the cloud coverage estimates. Reclassifying the values from land use datasets enabled the exclusion of unsuitable areas from the output maps. Eventually, the integration and visualization of the datasets result in output maps for each month within a year. The maps are the end product of the model and they can be used to focus decision making on the most suitable areas for utility-scale solar power plants. The model showed that the proportion of possible suitable areas was 40 % in Harare (original study area 40 000 km2), 55 % in Denver (90 000 km2) and 30 % in Helsinki (10 000 km2). This model did not exclude areas with low solar radiation potential. In Harare, the yearly variation in maximum radiation was low (100 kWh/m2/month), whereas in Denver it was 2.5-fold and in Helsinki 1.5-fold. The solar radiation variations within a single city were notable in Denver and Harare, but not in Helsinki. It is important to calculate radiation estimates using a digital elevation model and cloud coverage estimates rather than estimating the level of radiation in the atmosphere. This spatial information can be used for directing further investigations on potential sites for solar power plants. These further investigations could include land ownership, public policies and investment attractiveness.

Tässä tutkimuksessa perehdytään lukion maantieteen opetuksen sähköistämiseen niin yhteiskunnan digitaalisen murroskauden kuin myös ainetta opettavien opettajien kautta. Lukion maantieteen opettajien asema tutkimuksessa on keskeinen, koska heidän vastuullaan on opetussuunnitelman mukaisesti toteuttaa opetusta nykypäivän vaatimusten mukaan. Sähköistäminen on tapahtunut vauhdilla eivätkä opetusmenetelmät ole pysyneet mukana. Nuoret käyttävät usein sähköisiä välineitä paremmin kuin opettajansa. Ero kasvaa, kun opetetaan vanhoilla menetelmillä ja välineillä arjessaan uutta teknologiaa käyttäviä nuoria. Arjen ja tulevaisuuden vaatimukset tulisi saada kunnolla osaksi kouluopetusta. Viimeistään ylioppilaskirjoitusten sähköistäminen syksyllä 2016 herättää siihen, että sähköisiä opetusmenetelmiä ja -välineitä tulisi käyttää jo nyt. Mutta mikä tilanne on nyt ja miten opettajat asiaan suhtautuvat? Tässä tutkimuksessa selvitettiin sähköisen kyselytutkimuksen avulla eri puolella Suomea työskentelevien lukion maantieteen opettajien (n = 96) käyttämiä sähköisiä opetusmenetelmiä ja -välineitä sekä asenteita koko sähköistämistapahtumaan. Kolmantena tutkimuskysymyksenä toimi opetuksen sähköistymisen tulevaisuuden kehitys. Kyselyä täydensi kolmen asiantuntijan haastattelut aihepiiristä. Kyselyn tulokset analysoitiin ja esitettiin tilastokuvioina aina laitekäytettävyydestä oman tietoteknologiseen osaamisen arviointiin. Tulosten analysoinnin yleisenä linjana paljastui lukion maantieteen opettajien myönteinen asenne muutoksia kohtaan teoriassa, mutta uusien menetelmien ja välineiden ottaminen konkreettisesti mukaan opetukseen ei ollut ajan tasalla. Koulutuksen ja ajan puute, vähäiset resurssit ja osaamattomuus nousivat suurimmiksi kompastuskiviksi. Tutkimuksen mukaan opettajat kokivat, että ylioppilaskirjoitusten sähköistäminen tapahtuu liian nopeasti eikä koettu, että siitä olisi tiedotettu tarpeeksi. Perusohjelmat ja sähköiset opetusvälineet olivat käytössä yleisesti, mutta esimerkiksi tilastollisia menetelmiä ja paikkatieto-ohjelmia ei hyödynnetty vielä kaikkialla Suomessa. Tuloksista nousee esiin kysymys sähköisten ylioppilaskirjoitusten ajoituksesta ja siitä, miten maantieteen opetuksen käytännön puoli saataisiin mukaan päättäjätason edellyttämän kehityksen mukaiseksi.

Multiple factors determine diversity of diatoms in running waters. Diversity is a complex concept and made up by different components. Diversity can be divided into alpha, beta and gamma diversity. These different types of diversity are regulated by factors operating on a large geographic scale and by local environmental factors. Studies concentrating on diversity patterns of diatoms have become more common in the last 10 years. Especially beta diversity has gotten an increasing interest. Despite the increasing interest in the subject, the driving mechanisms are still not fully understood in aquatic ecosystems. The aim of this theses is to investigate which factors affect alfa and beta diversity in 10 streams in southern Finland. The influence of habitat heterogeneity on beta diversity is also investigated. In addition, the aim is to examine which local environmental factors structure the variation in species composition. The study area covers a 115 km wide area to minimize the effect of large scale factors on species composition. The material consists of environmental data and diatom data from 49 study sites. Land use data used in the study is derived from CORINE Land Cover 2012 data set. All samples were collected during a two-week period (30.7.2014–11.8.2014). Statistical methods used were linear models, generalized linear models (GLM), distance based redundancy analysis (db-RDA) and test for homogeneity of multivariate dispersions (PERMDISP). Water conductivity and light conditions at the study sites were strong environmental factors determining diatom alpha diversity. Habitat heterogeneity showed only a marginally significant positive relationship to beta diversity but a clear trend was visible in the data. The db-RDA results showed that different environmental factors accounted for the variation in species composition. Conductivity, light, water color, water temperature and stream width were important factors explaining variation in species composition. These results suggest that there is a possible connection between habitat heterogeneity and beta diversity. Further research in the subject should be done to determine if there is a significant relationship. The local environmental factors are important for structuring species composition. Possible anthropogenic stress factors influencing stream ecosystems can affect patterns of beta diversity and should be emphasizes in coming research.

The Tana fishing agreement was revised for the fishing season of 2017 amidst strong local opposition. The agreement deteriorates the survival prospects of the indigenous Sami culture. The aim of this study was to find out in what ways the legitimacy of the agreement was constructed and contested in the consultation process prior to the passing of the agreement. The results are examined in a broader temporal and geographical context of postcolonial power relations based on earlier research on the social construction of environmental conflicts, political participation of indigenous peoples, and environmental justice. Through a critical discourse analysis of written documents produced during the consultation process in May to October 2016, I identified five different discourses used by representatives of the state, the Sami, and other stakeholders. The passing of the agreement despite negative effects on the Sami was constructed as legitimate by making it appear as the only way to protect the salmon population, taking a short temporal perspective, depicting Tana as an abstract space devoid of culture, accepting existing power relations as given and presenting the Sami cultural rights as secondary to other concerns. The legitimacy was contested by emphasizing the historical legacy of colonial practices against the Sami culture, questioning the motives behind the agreement, proposing alternative ways to protect the salmon population, challenging the state to act according to its own rules and commitments and depicting Tana as a personal place full of cultural meaning. The discourses differ in what is considered as adequate or sufficient for the survival of the Sami culture and the realization of their indigenous rights in terms of cultural practice, participation, the knowledge base on which decisions are made, and owning up to the injustices committed in the past. The discourses used by representatives of the state bear a resemblance to the discriminatory politics of the last century and the othering of indigenous peoples elsewhere. The discursive context of the consultation process makes certain discourses appear more valid than others, which influences the choices of the Sami on how to phrase their opposition and concerns. In discourses used by many other stakeholders the cultural existence of the Sami is bypassed or ignored.

Global climate change is predicted to have a major impact on northern temperate and arctic zones climates. Rainfall and temperatures are likely to increase in the future decades. Increasing erosion is one of the major threats linked to these phenomena. In Finland specifically, winter months are expected to face the most radical change in climate. This master's thesis aims to answer the following questions: how much does erosion increase in changing climate, what are the factors that either increase or control erosion rates, and how well does the physically based SWAT- model behave in the settings of Southern Finland. Two gauging stations inside the study area were used to calibrate and validate the physical SWAT- model (Härkälänjoki and the lower-part of Lepsämänjoki). Total of 16 parameters controlling runoff were used. NS & R2 as well as P- & R-factors were chosen to quantify and measure model behavior. In the calibration period, the R2 & NS values for Härkälänjoki were 0,29 and -0,05, and for Lepsämänjoki 0,40 and 0,34. In the validation period, the R2 & NS values for Härkälänjoki were 0,30 and -0,57, and for Lepsämänjoki 0,54 and 0,21. In the calibration period, the P & R-values were 0,33 and 0,24 for Härkälänjoki and 0,32 and 0,29 for Lepsämänjoki. In the validation period, the P & R values were 0,42 and 0,57 for Härkälänjoki and 0,50 and 0,63 for Lepsämänjoki. The results of R2 and NS and the other criteria indicate that Lepsämänjoki responded better to model calibration and validation, being satisfactory. Values for Härkälänjoki were generally unsatisfactory. The RCP8.5 scenario used in this thesis increases erosion by approx. 94% compared to the validation period. However, spatial variability is considerable. Average annual erosion in the climate change scenario was 1,22 t/ha. Winter months contribute most to the total annual erosion. Areas covered by evergreen forests and located near the edges of the study area experience least erosion, while areas near the downstream of the river experience the most erosion. SWAT model behaved reasonably well, and worked well with high-quality GIS data. However, the model still needs some further adjustment and development in order to have more consistent and user-friendly interface.

African climate science is still underdeveloped; the related infrastructure is limited and climate observation network is sparse. The lack of observations is usually compensated with coarse macro-climate models (1 km2), of which only few concentrates on tropical Africa and on the spatial variability of rains. The need for fine-resolution data is growing, as more accurate information (5-100m) is utilized in different sciences. There has been a surge in micro-climate studies utilizing small dataloggers to observe climate variability, as loggers can be placed to different environments regardless of the complexity of a terrain. Accurate, fine-scale climate models are needed in ecological research, where species distributions are related to environmental gradients. Most of the studies describing species occurrences rely on macro-scale climate models that have been averaged over years, although the factors restricting species occurrences in an environment are developed even under one growth season, and are dependent on climate extremes. Accurate information of species and its occurrence environment is even more needed as climate is changing; species habitats are threatened through the warming of climate and its resulted effects. Fine-resolution data of micro-climate is needed especially in the studying of epiphytes living in tropical montane cloud forests, as epiphytes are dependent on the surrounding environments' specific atmospheric composition, namely relative humidity. The knowledge of epiphytic species distributions is poorly studied, although epiphytes are known to react fast to quick changes in environmental conditions. In this study small dataloggers were placed around the Taita Hills in a mountainous region of Kenya to record spatial and temporal micro-climate variability. Annual, monthly and extreme temperature and humidity parameters were studied through statistical spatial modelling, with generalized additive models (GAMs). The significance of each thriving factor of climate parameters were studied separately with bootstrapping. Of thousands of models created, temperature was best explained by elevation, and humidities by land cover (e.g. distance to forests), a proxy of canopy cover. Modelling extremes requires more research, as extreme models proved to be most difficult to model. More weight should be put on accurate environment gradients (e.g. canopy cover) when modelling spatial climate variability in a fine-scale. Created fine-resolution grids were tested in modelling the distributions of epiphytic species through Boosted Regression Trees (BRT). Models created gave an insight to the drivers of epiphytic species distributions and to the limitations of their occurrences in a limited environment. Different explanatory variable groups were tested (topographical, in situ, climate groups), of which climate explained most of the variations in epiphytic species occurrences when considered with AUC-values. Some epiphytes seemed to be specialized to certain habitat trees, highlighting the value of not only indigenous trees but exotic ones. Epiphytes were restricted to occur under certain temperatures and humidities ranges that is an indication of the vulnerability of epiphytes to changing climate.