2 resultados para Environmental factor

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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The environmental impacts of a single mine often remain local, but acidic and metal-rich acid mine drainage (AMD) from the waste materials may pose a serious threat to adjacent surface waters and their ecosystems. Testate amoebae (thecamoebian) analysis was used together with lake sediment geochemistry to study and evaluate the ecological effects of sulphidic metal mines on aquatic environments. Three different mines were included in the study: Luikonlahti Cu-mine in Kaavi, eastern Finland, Haveri Cu-Au mine in Ylöjärvi, southern Finland and Pyhäsalmi Zn-Cu-S mine in Pyhäjärvi, central Finland. Luikonlahti and Haveri are closed mines, but Pyhäsalmi is still operating. The sampling strategy was case specific, and planned to provide a representative sediment sample series to define natural background conditions, to detect spatial and temporal variations in mine impacts, to evaluate the possible recovery after the peak contamination, and to distinguish the effects of other environmental factors from the mining impacts. In the Haveri case, diatom analyses were performed alongside thecamoebian analysis to evaluate the similarities and differences between the two proxies. The results of the analyses were investigated with multivariate methods (direct and indirect ordinations, diversity and distance measure indices). Finally, the results of each case study were harmonized, pooled, and jointly analyzed to summarize the results for this dissertation. Geochemical results showed broadly similar temporal patterns in each case. Concentrations of ions in the pre-disturbance samples defined the natural baseline against which other results were compared. The beginning of the mining activities had only minor impacts on sediment geochemistry, mainly appearing as an increased clastic input into the lakes at Haveri and Pyhäsalmi. The active mining phase was followed by the metallic contamination and, subsequently, by the most recent change towards decreased but still elevated metal concentrations in the sediments. Because of the delay in the oxidation of waste material and formation of AMD, the most intense, but transient metal contamination phase occurred in the post-mining period at Luikonlahti and Haveri. At Pyhäsalmi, the highest metal contamination preceded effluent mitigation actions. Spatial gradients were observed besides the temporal evolution in both the pre-disturbance and mine-impacted samples from Luikonlahti and Pyhäsalmi. The geochemical gradients varied with distance from the main source of contaminants (dispersion and dilution) and with water depth (redox and pH). The spatial extent of the highest metal contamination associated with these mines remained rather limited. At Haveri, the metallic impact was widespread, with the upstream site in another lake basin found to be contaminated. Changes in thecamoebian assemblages corresponded well with the geochemical results. Despite some differences, the general features and ecological responses of the faunal assemblages were rather similar in each lake. Constantly abundant strains of Difflugia oblonga, Difflugia protaeiformis and centropyxids formed the core of these assemblages. Increasing proportions of Cucurbitella tricuspis towards the surface samples were found in all of the cases. The results affirmed the indicator value of some already known indicator forms, but such as C. tricuspis and higher nutrient levels, but also elicited possible new ones such as D. oblonga ‘spinosa’ and clayey substrate, high conductivity and/or alkalinity, D. protaeiformis ‘multicornis’ and pH, water hardness and the amount of clastic material and Centropyxis constricta ‘aerophila’ and high metal and S concentrations. In each case, eutrophication appeared to be the most important environmental factor, masking the effects of other variables. Faunal responses to high metal inputs in sediments remained minor, but were nevertheless detectable. Besides the trophic state of the lake, numerical methods suggested overall geochemical conditions (pH, redox) to be the most important factor at Luikonlahti, whereas the Haveri results showed the clearest connection between metals and amoebae. At Pyhäsalmi, the strongest relationships were found between Ca- and S-rich present loading, redox conditions and substrate composition. Sediment geochemistry and testate amoeba analysis proved to be a suitable combination of methods to detect and describe the aquatic mine impacts in each specific case, to evaluate recovery and to differentiate between the effects of different anthropogenic and natural environmental factors. It was also suggested that aquatic mine impacts can be significantly mitigated by careful design and after-care of the waste facilities, especially by reducing and preventing AMD. The case-specific approach is nevertheless necessary because of the unique characteristics of each mine and variations in the environmental background conditions.

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The structural change of society from product-based business to service- and further to need-based business has caused the fact that work for environmental issues has spread from conventional factories and environmentally harmful production to concern services and offices as well. Almost every company has an office, so a relatively small environmental burden caused by an individual office grows remarkable already at the state level and globally even more. Motivation to work for environmental issues in an individual office could be challenging even without the fact that wasted environmental impacts bound also wasted costs. Besides cost savings, a concretely greener image of a company has its value in the B2Cas well as in the B2B-field. Consumers and clients are more and more conscious of environmental issues and demand concrete actions instead of speeches, good thoughts and meaningless certifications. Internal work for environmental issues at a strategy level is not sufficient, so operational environmental management is needed for changing old practices. This research is about the effects of operative environmental management on the greening process of an office-based business. The research is outlined to concern the operative work in the office including field sales. Target was to concretely lower the environmental impacts of Lyreco Finland and to find cost savings directly by changing the operative practices in the office and also indirectly by affecting the level of environmental knowledge of the personnel. During the greening process, the aim was also to create concrete arguments for marketing as well. The circle of greening process, which was especially created for this diploma work, was used as a method. The circle divides a year to themes and sections separated by factors of environmental impacts. Separation is based on Brett Wills’ thoughts of seven green wastes (Wills, Brett. The Green Intensions. 2009) and follows it uneasily. The circle aimed at ensuring evolutionary growth of knowledge instead of being revolutionary in the changing process. Committing personnel to the process from its start by asking ideas from them and giving them clear directions was an important part of the research of operative management. Because of working from distance, communication with personnel was operated by frequent training days and weekly greening notes via emails and intranet. Also availability for communication was an important task because of the telecommuting. Research results of this work show that operative environmental management in an officebased business today is mostly management of change. When the strategic environmental friendliness is taken into a concrete level, the most important individual factor is motivating the operating personnel. Research shows that evolutionary change is found being an efficient way to make a change. Also understanding one´s own impact on the environmental burden and on the whole greening process clearly motivates the personnel. Results show that in the operative realization of the greening process, clear directions of new working practices, being as concrete as possible, and committing personnel to follow them make the process more effective. The operative environmental management and the cycle of the greening process decrease the environmental burden and save costs. The concrete results could be used as believable arguments in marketing and therefore exploited in communication with interest groups. Commitment of the management is also one of the key factors of success in the greening process. In this research, changes in the business field by a company trade took the focus of the management away from the greening process and made the process more inefficient by decreasing the amount of training days. The circle of greening process will be used as a tool in the future, as well, and therefore it will help observe environmental impacts of a company and increase sustainable development. Commitment of management to the evolutionary environmental work helps the operating personnel lower environmental impacts, decrease costs and build a concretely greener image.