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This thesis describes the occurrence and sources of selected persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and hexachlorocyclohexanes (HCHs) in the northern watershed of Lake Victoria. Sediments and fish were collected from three highly polluted embayments (i.e. Murchison Bay, Napoleon Gulf and Thurston Bay) of the lake. The analysis for PCDD/Fs, PCBs and PBDEs was done using a high resolution mass spectrometer coupled to a gas chromatograph (GC), and a GC equipped with an electron capture detector was used for HCHs. Total (Σ) PCDD/Fs, PCBs and PBDEs in sediments ranged from 3.19 to 478, 313 to 4325 and 60.8 to 179 pg g-1 dry weight (dw), respectively. The highest concentrations of pollutants were found at sites close to industrial areas and wastewater discharge points. The maximum concentrations of PCDD/Fs, PCBs, PBDEs and HCHs in fish muscle homogenates were 49, 779, 495 and 45,900 pg g-1 wet weight (ww), respectively. The concentrations of the pollutants in Nile perch (Lates niloticus) were significantly greater than those in Nile tilapia (Oreochromis niloticus), possibly due to differences in trophic level and dietary feeding habits among fish species. World Health Organization-toxic equivalency quotient (WHO2005-TEQ) values in the sediments were up to 4.24 pg g-1 dw for PCDD/Fs and 0.55 pg TEQ g-1 dw for the 12 dioxin-like PCBs (dl-PCBs). 23.1% of the samples from the Napoleon Gulf were above the interim sediment quality guideline value of 0.85 pg WHO-TEQ g-1 dw set by the Canadian Council for Ministers of the Environment. The WHO2005-TEQs in fish were 0.001-0.16 pg g-1 for PCDD/Fs and 0.001-0.31 pg g-1 ww for dl- PCBs. The TEQ values were within a permissible level of 3.5 pg g−1 ww recommended by the European Commission. Based on the Commission set TEQs and minimum risk level criteria formulated by the Agency for Toxic Substances and Disease Registry, the consumption of fish from Lake Victoria gives no indication of health risks associated to PCDD/Fs and PCBs. Principal component analysis (PCA) indicated that anthropogenic activities such as agricultural straw open burning, medical waste incinerators and municipal solid waste combustors were the major sources of PCDD/Fs in the watershed of Lake Victoria. The ratios of α-/γ-HCH varied from 0.89 to 1.68 suggesting that the highest HCH residues mainly came from earlier usage and fresh γ-HCH (lindane). In the present study, the concentration of POPs in fish were not significantly related to those in sediments, and the biota sediment accumulation factor (BSAF) concept was found to be a poor predictor of the bioavailability and bioaccumulation of environmental pollutants.

The aim of this thesis was to study how small logistics sector and fish sector companies in Kymenlaakso region have experienced the effects of Russia’s counter-sanctions. The main research questions in the study were “Have the Russia’s counter-sanctions affected companies’ businesses in Kymenlaakso region?”, “What kind of effect(s) have the companies identified and encountered?”, “What measures have companies taken regarding the situation?” and “Have the companies tried to find new markets for their products or services?”. The primary research method in this study was a semi-structured interview. The author of this thesis interviewed professionals and experts from different companies from the chosen sectors during spring 2015. The findings show that small companies in the logistics sector and fish sector have experienced either direct or indirect effects that have been caused by the counter-sanctions. Main challenges for the fish sector are decreases in producer prices and tightened competition in the European Union area. The logistics sector has experienced difficulties due to tightened liquidity conditions. There have also been bankruptcies in the logistics sector directly caused by the counter-sanctions. Companies in both sectors have been forced to look for alternative markets, postpone investments and lay-off or terminate personnel. Scepticism and uncertainty regarding trade with Russian customers and companies have emerged. On a national level, Finland’s container balance has been negatively affected partly due to the counter-sanctions. The scope of this study is limited to small fish sector and logistics sector companies in Kymenlaakso region. Also, due to the qualitative nature of the primary research method the findings of this study are not generalizable to the public. Tämän opinnäytetyön tarkoituksena oli tarkastella sitä miten pienet logistiikka –ja kalasektorin yritykset Kymenlaakson alueella ovat kokeneet Venäjän asettamien vastapakotteiden vaikutukset. Opinnäytetyön tutkimuskysymykset olivat ”Ovatko Venäjän vastapakotteet vaikuttaneet yritysten toimintaan Kymenlaakson alueella?”, ”Millaisia vaikutuksia yritykset ovat kohdanneet ja identifioineet?”, ”Mitä toimenpiteitä yritykset ovat tehneet tilanteeseen liittyen?” ja ”Ovatko yritykset pyrkineet löytämään tuotteilleen tai palveluilleen uusia markkinoita?”. Tämän opinnäytetyön ensisijainen tutkimusmenetelmä oli semistrukturoitu haastattelu. Opinnäytetyön tekijä haastatteli asiantuntijoita sekä ammattilaisia valituilta sektoreilta kevään 2015 aikana. Tulokset näyttävät, että pienet logistiikka –ja kalasektorin yritykset ovat kohdanneet joko suoria tai epäsuoria vastapakotteiden aiheuttamia vaikutuksia. Keskeisimmät haasteet kalasektorilla johtuvat tuottajahintojen laskusta sekä kiristyneestä kilpailuista Euroopan Union alueella. Logistiikkasektorilla on kohdannut vaikeuksia, jotka ovat johtuneet yritysten hankaloituneesta likviditeettitilanteesta. Myös vastapakotteiden suoraan aiheuttamia konkursseja on havaittu. Molempien sektorien yritykset ovat joutuneet etsimään tuotteilleen tai palveluilleen uusia markkinoita, viivästyttämään investointeja sekä lomauttamaan tai irtisanomaan henkilöstöä. Skeptisyys sekä epävarmuus kaupankäynnissä venäläisten asiakkaiden sekä yritysten kanssa on noussut esiin. Kansallisella tasolla vastapakotteilla on osaltaan ollut negatiivinen vaikutus Suomen konttitasapainoon. Tämän opinnäytetyö on rajoitettu tarkastelemaan pieniä logistiikka – ja kalasektorin yrityksiä Kymenlaakson alueella. Lisäksi, johtuen kvalitatiivisesta tutkimusmenetelmästä tämän opinnäytetyön tuloksia ei voida pitää yleistettävinä muihin yrityksiin.

Analyzing and improving marketing strategies of Thien Hong Joint Stock company - a newborn company in the field of sea freight forwarding service in Vietnam. This thesis focused on the 4Ps (product, price, placement, promotion) in marketing strategy, how to apply the theory of services marketing in a business to business company and a special industry effectively.

Arkona Basin (southwestern Baltic Sea) is a seasonally-hypoxic basin characterized by the presence of free methane gas in its youngest organic-rich muddy stratum. Through the use of reactive transport models, this study tracks the development of the methane geochemistry in Arkona Basin as this muddy sediment became deposited during the last 8 kyr. Four cores are modeled each pertaining to a unique geochemical scenario according to their respective contemporary geochemical profiles. Ultimately the thickness of the muddy sediment and the flux of particulate organic carbon are crucial in determining the advent of both methanogenesis and free methane gas, the timescales over which methanogenesis takes over as a dominant reaction pathway for organic matter degradation, and the timescales required for free methane gas to form.

Purpose: Identify impacts of Song Bung 4 Hydropower project to diversity and hydrology; Criticise on mitigation practice and impacts. Method: Screen of impacts from records of other projects and mitigations; Compare with identified impacts and mitigation practices. Findings: Direct lost of some species; environmental flow is not implemented regularly; higher fish yield in reservoir; threaten migratory fish

Enhanced release of alkalinity from the seafloor, principally driven by anaerobic degradation of organic matter under low-oxygen conditions and associated secondary redox reactions, can increase the carbon dioxide (CO2) buffering capacity of seawater and therefore oceanic CO2 uptake. The Baltic Sea has undergone severe changes in oxygenation state and total alkalinity (TA) over the past decades. The link between these concurrent changes has not yet been investigated in detail. A recent system-wide TA budget constructed for the past 50 years using BALTSEM, a coupled physical–biogeochemical model for the whole Baltic Sea area revealed an unknown TA source. Here we use BALTSEM in combination with observational data and one-dimensional reactive-transport modeling of sedimentary processes in the Fårö Deep, a deep Baltic Sea basin, to test whether sulfate (SO42-) reduction coupled to iron (Fe) sulfide burial can explain the missing TA source in the Baltic Proper. We calculated that this burial can account for up to 26 % of the missing source in this basin, with the remaining TA possibly originating from unknown river inputs or submarine groundwater discharge. We also show that temporal variability in the input of Fe to the sediments since the 1970s drives changes in sulfur (S) burial in the Fårö Deep, suggesting that Fe availability is the ultimate limiting factor for TA generation under anoxic conditions. The implementation of projected climate change and two nutrient load scenarios for the 21st century in BALTSEM shows that reducing nutrient loads will improve deep water oxygen conditions, but at the expense of lower surface water TA concentrations, CO2 buffering capacities and faster acidification. When these changes additionally lead to a decrease in Fe inputs to the sediment of the deep basins, anaerobic TA generation will be reduced even further, thus exacerbating acidification. This work highlights that Fe dynamics plays a key role in the release of TA from sediments where Fe sulfide formation is limited by Fe availability, as exemplified by the Baltic Sea. Moreover, it demonstrates that burial of Fe sulfides should be included in TA budgets of low-oxygen basins.

Variability and long-term climate change in the Baltic Sea region is investigated for the pre-industrial period of the last millennium. For the first time dynamical downscaling covering the complete millennium is conducted with a regional climate model in this area. As a result of changing external forcing conditions, the model simulation shows warm conditions in the first centuries followed by a gradual cooling until ca. 1700 before temperature increases in the last centuries. This long-term evolution, with a Medieval Climate Anomaly (MCA) and a Little Ice Age (LIA), is in broad agreement with proxy-based reconstructions. However, the timing of warm and cold events is not captured at all times. We show that the regional response to the global climate anomalies is to a strong degree modified by the large-scale circulation in the model. In particular, we find that a positive phase of the North Atlantic Oscillation (NAO) simulated during MCA contributes to enhancing winter temperatures and precipitation in the region while a negative NAO index in the LIA reduces them. In a second step, the regional ocean model (RCO-SCOBI) is used to investigate the impact of atmospheric changes onto the Baltic Sea for two 100 yr time slices representing the MCA and the LIA. Besides the warming of the Baltic Sea, the water becomes fresher at all levels during the MCA. This is induced by increased runoff and stronger westerly winds. Moreover, the oxygen concentrations in the deep layers are slightly reduced during the MCA. Additional sensitivity studies are conducted to investigate the impact of even higher temperatures and increased nutrient loads. The presented experiments suggest that changing nutrient loads may be more important determining oxygen depletion than changes in temperature or dynamic feedbacks.

The growing population requires a lot of food in order to sustain itself. Therefore, also, more fish need to be caught and farmed. Since a large amount of fish captured cannot be used commercially, it is usually thrown away, which in turn can be hazardous to the environment not to mention sea birds. By catch is also caught when fishing. A circular approach to this fish waste means seeing this waste as something that should be used instead of being thrown away. Usually fish waste if not discharged overboard, is converted into fish meal or fish oil. It is often costly and time-consuming. The heterogeneous nature of fish waste is an added challenge because finding solutions that work all the time with all types of fish waste is not possible. The lab-scale applications mentioned in this thesis include, but are not limited to, turning fish waste into fertilizer, feed, nutrients, peptides, enzymes, hydrolysates, biomaterials, wastewater treatment products, and biofuels. This thesis was a literature review, and no lab work was donewhen making it.Fertilizer and feed are relatively straight-forward to do, but they require more time to be aged than their commercial counterparts. Nutrients, peptides, hydrolysates, and enzymes can also be extracted from the fish waste; however, in the case of mincing the fish waste it can only replace part of the fish meat. Peptides showed interesting properties but required more research to be identified precisely. Hydroly-sates could be used for capturing moisture in the food industry, but their inner bitterness needs to be masked beforehand. Enzymes can be extracted, but their performance varies; an enzyme for dehairing leather works great, but an enzyme to make cheese creates a cheese that cannot hold moisture inside it. Fish waste can also be added into packaging materials, where the biodegradability increase, but this comes at the cost of weaker strength and an inability to hold moisture inside the package. Their properties can be improved by adding additional substances into the material. Fish waste can also be used to manufacture sorbents for treating wastewater and in the articles they could remove, for example, azodyes and lead. Fish waste can also be converted into biofuels. However, they increase some emissions, while simultaneously reducing others and they cannot be stored as long as conventionally made diesel. Fish waste has many potential applications, but their large-scale implementation requires massive investments in a circular economy.

Abstract Background Clupeid fisheries in Lake Tanganyika (East Africa) provide food for millions of people in one of the world’s poorest regions. Due to climate change and overfishing, the clupeid stocks of Lake Tanganyika are declining. We investigate the population structure of the Lake Tanganyika sprat Stolothrissa tanganicae, using for the first time a genomic approach on this species. This is an important step towards knowing if the species should be managed separately or as a single stock. Population structure is important for fisheries management, yet understudied for many African freshwater species. We hypothesize that distinct stocks of S. tanganicae could be present due to the large size of the lake (isolation by distance), limnological variation (adaptive evolution), or past separation of the lake (historical subdivision). On the other hand, high mobility of the species and lack of obvious migration barriers might have resulted in a homogenous population. Results We performed a population genetic study on wild-caught S. tanganicae through a combination of mitochondrial genotyping (96 individuals) and RAD sequencing (83 individuals). Samples were collected at five locations along a north-south axis of Lake Tanganyika. The mtDNA data had low global FST and, visualised in a haplotype network, did not show phylogeographic structure. RAD sequencing yielded a panel of 3504 SNPs, with low genetic differentiation (FST = 0.0054; 95% CI: 0.0046–0.0066). PCoA, fineRADstructure and global FST suggest a near-panmictic population. Two distinct groups are apparent in these analyses (FST = 0.1338 95% CI: 0.1239,0.1445), which do not correspond to sampling locations. Autocorrelation analysis showed a slight increase in genetic difference with increasing distance. No outlier loci were detected in the RADseq data. Conclusion Our results show at most very weak geographical structuring of the stock and do not provide evidence for genetic adaptation to historical or environmental differences over a north-south axis. Based on these results, we advise to manage the stock as one population, integrating one management strategy over the four riparian countries. These results are a first comprehensive study on the population structure of these important fisheries target species, and can guide fisheries management.

In this thesis, the creation of a Python based interactive map of the world’s wave energy resources is explained and presented. The application will be used by Wello Oy to generate values needed in wave energy production in various locations across the world, and to calculate the theoretical power of Wello’s Penguin wave energy converter. The application is planned to be used as an easy-to-use tool to quickly and effectively measure the power output of the Penguin wave energy converter at any given site in the world. The application allows tailored results that are calculated by using values obtained from each potential wave energy site. The results show the end user the wave energy at the site, and the optimal dimensions of the wave energy converter for maximal power production and maximal return of investment. The fundamentals of wave energy and wave energy converters are discussed, as well as the methodology for calculating the theoretical power output of waves and calculating the levelized cost of energy at each of these sites. All this is done in hope of making the process of finding potential wave energy projects more efficient and effective, and thus providing a clean, renewable and continuous energy source to the world.