20 resultados para Receiving waters


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Reverse osmosis and nanofiltration are among the most effective and widely used desalination and water softening technologies. They can also be used to treat mining wastewaters and are capable of producing water of extremely high purity, regardless of the high concentrations of toxic heavy metals and extreme pH and salinity. However, challenges with recovering the salts and metals from mining wastewaters in exploitable form, as well as problems with scaling still limit the process efficiency and the ratio of purified water recoverable from process waters. To address the problem of membrane scaling caused by calcium sulfate, batch filtration experiments with the Desal-5 DL nanofiltration membrane, three commercial antiscalants and actual mine process water from a copper mine were performed. The aim of these experiments was to find process conditions where maximum water recovery would be achieved before significant scaling or irreversible membrane fouling would occur and to further improve water recovery by addition of antiscalants. Water recovery of 70 % was reached with the experimental setups by optimizing process conditions. PC-504T antiscaling agent was determined to be the most effective of the three antiscalants used and the addition of 5 ppm of PC-504T allowed the water recovery to be further increased from 70 % to 85 % before major scaling was observed. In these conditions 92 % calcium rejection was achieved.

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The distribution and traits of fish are of interest both ecologically and socio-economically. In this thesis, phenotypic and structural variation in fish populations and assemblages was studied on multiple spatial and temporal scales in shallow coastal areas in the archipelago of the northern Baltic Proper. In Lumparn basin in Åland Islands, the fish assemblage displayed significant seasonal variation in depth zone distribution. The results indicate that investigating both spatial and temporal variation in small scale is crucial for understanding patterns in fish distribution and community structure in large scale. The local population of Eurasian perch Perca fluviatilis L displayed habitat-specific morphological and dietary variation. Perch in the pelagic zone were on average deeper in their body shape than the littoral ones and fed on fish and benthic invertebrates. The results differ from previous studies conducted in freshwater habitats, where the pelagic perch typically are streamlined in body shape and zooplanktivorous. Stable isotopes of carbon and nitrogen differed between perch with different stomach contents, suggesting differentiation of individual diet preferences. In the study areas Lumparn and Ivarskärsfjärden in Åland Islands and Galtfjärden in Swedish east coast, the development in fish assemblages during the 2000’s indicated a general shift towards higher abundances of small-bodied lower-order consumers, especially cyprinids. For European pikeperch Sander lucioperca L., recent declines in adult fish abundances and high mortalities (Z = 1.06–1.16) were observed, which suggests unsustainably high fishing pressure on pikeperch. Based on the results it can be hypothesized that fishing has reduced the abundances of large predatory fish, which together with bottom-up forcing by eutrophication has allowed the lower-order consumer species to increase in abundances. This thesis contributes to the scientific understanding of aquatic ecosystems with new descriptions on morphological and dietary adaptations in perch in brackish water, and on the seasonal variation in small-scale spatial fish distribution. The results also demonstrate anthropogenic effects on coastal fish communities and underline the urgency of further reducing nutrient inputs and regulating fisheries in the Baltic Sea region.

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In coastal waters, physico-chemical and biological properties and constituents vary at different time scales. In the study area of this thesis, within the Archipelago Sea in the northern Baltic Sea, seasonal cycles of light and temperature set preconditions for intra-annual variations, but developments at other temporal scales occur as well. Weather-induced runoffs and currents may alter water properties over the short term, and the consequences over time of eutrophication and global changes are to a degree unpredictable. The dynamic characteristics of northern Baltic Sea waters are further diversified at the archipelago coasts. Water properties may differ in adjacent basins, which are separated by island and underwater thresholds limiting water exchange, making the area not only a mosaic of islands but also one of water masses. Long-term monitoring and in situ observations provide an essential data reserve for coastal management and research. Since the seasonal amplitudes of water properties are so high, inter-annual comparisons of water-quality variables have to be based on observations sampled at the same time each year. In this thesis I compare areas by their temporal characteristics, using both inter-annual and seasonal data. After comparing spatial differences in seasonal cycles, I conclude that spatial comparisons and temporal generalizations have to be made with caution. In classifying areas by the state of their waters, the results may be biased even if the sampling is annually simultaneous, since the dynamics of water properties may vary according to the area. The most comprehensive view of the spatiotemporal dynamics of water properties would be achieved by means of comparisons with data consisting of multiple annual samples. For practical reasons, this cannot be achieved with conventional in situ sampling. A holistic understanding of the spatiotemporal features of the water properties of the Archipelago Sea will have to be based on the application of multiple methods, complementing each other’s spatial and temporal coverage. The integration of multi-source observational data and time-series analysis may be methodologically challenging, but it will yield new information as to the spatiotemporal regime of the Archipelago Sea.

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Kanadalaisen kirjailijan L. M. Montgomeryn tunnetun ja rakastetun Anna-sarjan ensimmäinen osa Anne of Green Gables -teos (1908) kertoo orvosta tytöstä, joka pääsee Prinssi Edwardin saaren Avonlean kylään asumaan naimattoman sisarusparin Marilla ja Matthew`n kasvattilapseksi. Luonto on keskeisellä sijalla teoksessa: Anna on luontoa rakastava ja luonnon keskellä viihtyvä tyttö ja myös teoksen kertoja kuvaa paljon luontoa. Tutkimukseni käsittelee luontoa Anne of Green Gables -teoksessa. Tutkin luontoteemaa teoksessa seuraavista näkökulmista: Analysoin, kuinka luonto kuvataan teoksessa ja millainen on teoksen luontokuva. Luontokuvaa käsittelen pastoraalin käsitteen kautta, ja kysyn teokselta, voidaanko se tulkita pastoraaliksi ja kuinka teos asettuu pastoraalin traditioon. Lisäksi erittelen, millainen on päähenkilön Annan luontosuhde. Millaisen arvon hän antaa luonnolle ja mitä merkityksiä hän liittää luontoon? Tutkimus asettuu ekokriittiseen viitekehykseen, ja pohdin myös sitä, minkälainen on teoksen representaatio luonnosta ekokriittisesti tarkastellen. Amerikkalaisen transsendentalistin Ralph Waldo Emersonin luontofilosofia kulkee myös taustajuonteena tutkielmassa ja erittelen, mitä yhtymäkohtia hänen luontofilosofiassaan on Anne of Green Gables -teokseen. Anne of Green Gables -teoksen luontokuvaa voidaan luonnehtia romantisoiduksi ja idealisoivaksi. Luonto kuvataan kauniiksi, ja sen kauneutta ylistää niin Anna kuin teoksen kaikkitietävä kertojakin. Teoksen luontokuva on pastoraalinen, sillä siinä esiintyy vahvasti pastoraaliin liittyvä diskurssi maaseudun ja kaupungin vastakkainasettelusta siten, että maaseutu assosioituu positiivisesti, kun taas kaupunki nähdään negatiivisessa valossa. Luonnonläheinen Avonlean kylä näyttäytyy teoksessa niin idealisoidussa valossa, että se muistuttaa jo jonkinlaista myyttistä paratiisia. Näin ollen teoksen pastoraalisuus saa pejoratiivisiakin piirteitä. Annan luontosuhdetta värittää voimakas kunnioitus ja arvostus luontoa kohtaan. Hänen luontoon liittämistä arvoista keskeiselle sijalle nousee luonnon kauneus. Luonnon kauneuden arvostaminen toimii kuitenkin porttina luonnon toiseuttamiseen, mistä syntyy pieni arvoristiriita. Toisaalta kuitenkin Anna samaistuu luontoon tavalla, joka hämärtää perinteistä subjekti–objekti-dikotomiaa. Anna näyttäytyy vihreän maailman arkkityyppinä, lapsena, joka sulautuu luontoon ja kokee sen kodikseen. Luonto edustaa Annalle vapautta ja herättää myös hänen mielikuvituksena ja taiteellisen inspiraation. Lisäksi luonto on Annalle paikka, jossa voi saavuttaa autenttisen yhteyden Jumalaan.

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This thesis discusses the unexplored opportunities of open innovation, with a special focus on outbound open innovation. The extant literature indicates that the field of outbound open innovation still lacks of research, and especially the managerial issues lack of practicality. Also, the applicability to SME’s and traditional fields has been argued. The purpose of this study is to investigate how the outbound open innovation activities can be managed in maritime industry. By combining existing literature from the field of open innovation and innovation management, this study suggests first a theoretical management model, and contributes how it can be applied to industry- and company specifics; and then develops a practical model by constructing from the case company’s current management processes. As a result, the study synthesises a theoretical model of how the outbound open innovation activities can be managed. This model positions the outbound open innovation activities, the theoretical concepts found from the literature review, R&D processes, and the outbound open innovation implementation stages identified by previous research; and thus responses the need for practical steps for any company planning outbound open innovation activities. Practical tool for managers is also provided by identifying issues that are applied to industry- and company specifics. Then, open-ended case study questions are formulated accordingly and expert interviews selected by chain referral sampling, are conducted. Interviews provide information for the current management processes. By identifying the best practices and main challenges it is possible to outline and evaluate current outbound open innovation management processes and strategic choices in it. The researcher considers also the networks and their spheres of influences for the actors, activities and resources in the processes. Thus, the study provides a novel approach, and practical tools for the researchers and practioners in the field of open innovation. All in all, the study has come up that outbound open innovation is applicable to maritime industry; and the case company indeed has perfected its processes as cost-effective as possible, and so found its balance between the costs and benefits. However, several issues for future development are pointed out, and the study offers proposals for theory building. Findings are piloting in kind, but provide several theoretical and managerial implications, and reveal new research needs for the field.