847 resultados para commitment towards the supervisor


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The dissertation focuses on the development of music education in Estonian kindergartens and the factors influencing it, analysed in the historical perspective relying on post-positivist paradigm. The study is based on the factors and subjects’ views on kindergarten music education from 1905 to 2008, recorded in written sources or ascertained by means of questionnaire and interview. The dissertation deals with music’s functions, music education in retrospective, factors influencing child’s musical aptitude and development and teacher’s role in it through the prism of history. The formation of Estonian kindergarten music education and the phenomenon of its development have been researched by stages: the first manifestations of music in kindergarten in 1905 - 1940; the formation of the concept of music education in 1941 - 1967 and the application of a unified system in 1968 - 1990. The work also outlines innovative trends in music education at the end of the last millennium and the beginning of this century, in 1991 - 2008. The study relies on a combined design and an analysis of historical archival material and empirical data. The empirical part of the study is based on the questionnaire (n=183) and interviews (n=18) carried out with kindergarten music teachers. The data has been analysed using both qualitative and quantitative methods. The subject of the research is the content and activity types of kindergarten music education and the role of music teacher in their implementation. The study confirmed that fundamental changes took place in Estonian kindergarten music education due to the change in political power in the 1940s. Following the example of the Soviet system of education, music in kindergarten became an independent music educational orientation and the position of a professionally trained music teacher was established (1947). It was also confirmed that in the newly independent Estonian Republic under the influence of innovative trends a new paradigm of music education arose from the traditional singing-centred education towards the more balanced use of music activity types (attaching importance to the child-centred approach, an increase in the number and variety of activity types). The most important conclusions made in the dissertation are that there has been improvement and development deriving from contemporary trends in the clear concept that has evolved in Estonian kindergarten music education over a century; professionally trained music teachers have had a crucial role in shaping it; and kindergarten music education is firmly positioned as a part of preschool education in Estonian system of education. Key words: early childhood music education, history of music education, kindergarten music education, early childhood music teachers

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The aim of this qualitative study is to chart the operational context of the upper-secondary school principals and the historical, cultural and structural factors that steer their day-to-day work. The concepts regarding the study environment and operational culture are defined and analysed in terms of how they are interrelated. Furthermore it is explained why the upper-secondary schools must describe their operational culture within the curriculum. The study also aims to connect the description of the operational culture with the operational system of the upper-secondary school and to analyse the descriptions of the five upper-secondary schools in relation to the commitment to developing a study environment conducive to learning and participation, as well as conducive to supporting interaction. Interview data is used to provide the background for the description of the operational culture and to particularise the results of the analysis. According to the theory used in this study, the steering sources of the day-to-day work of the upper-secondary school are the rules system of the state, the municipality, the curriculum, and on the level of the upper-secondary school administration. The research data consist of the literature concerning the steering, steering forms and the principals professional picture in general terms, from 1950 to the present, and the steering texts concerning the educational environment and operational culture. Furthermore the research data include five descriptions of the operational culture concerning the upper-secondary school, the action reports and student guides. The methods of analysis include the level model and content analysis. The first is a part of the theory used in this study. For the purpose of content analysis, moreover, classifying grounds are established on the basis of theoretical and empirical research data. A result of this study is that, from the perspective of steering, the function of describing the operational culture is clearly linked to the evaluation supporting the goals and the vision of a learning organization. From an administrative point of view, a description is a problem-solving strategy and an instrument of evaluation. The study environment is a structural context in and through which the actors of the school create, change and renew the elements of the structure rooted in the context; this structure is their historically and culturally mediated way of thinking and acting. The initial situation and orientation of the students affect the emphasis of the operational culture descriptions; principals also have their own personal style of leadership. Key words: source of steering, educational environment, operational culture, self-evaluation, learning organisation

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Liquid chromatography/mass spectrometry (MS)/MS was used to analyse toxins in P. trichostachia, P. simplex subsp. continua, P. simplex subsp. continua and P. elongata samples (flowers, seeds, branches, main stem, leaves and roots) collected from various locations in Queensland, Saskatchewan and New South Wales, Australia. Simplexin was the major analyte in all taxa, with varying minor levels of huratoxin. Simplexin levels in P. trichostachia and P. elongata were higher (580 and 540 mg/kg in flowering foliage, respectively) than in P. simplex (255 mg/kg). Levels of huratoxin were higher in P. simplex (relative to simplexin) than in P. trichostachia or P. elongata. P. simplex flower heads and roots contained similar simplexin levels, with very small amounts of toxins detected in branches, stems and leaves. In P. trichostachia, simplexin levels were high in flower heads but low in the the other plant parts. The simplexin levels in aerial parts were generally higher from the pre-flowering to the flowering stage, decreasing towards the post-flowering stage; similar trends were recorded for P.elongata samples collected from a site near Bollon and P. trichostachia samples collected from a site near Jericho (both sites in Queensland). The simplexin concentration in roots was much less variable. Flowers and seeds had much higher simplexin levels than the foliage. The breakdown of the toxin in litter was more rapid compared to seeds under the same weathering conditions. Unlike the results from the litter samples, no significant decrease occurred in seed samples after 18 months of exposure.

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The role of the immune system is to protect an organism against pathogens while maintaining tolerance against self. T cells are an essential component of the immune system and they develop in the thymus. The AIRE (autoimmune regulator) gene product plays an important role in T cell development, as it promotes expression of peripheral tissue antigens in the thymus. Developing T cells, thymocytes, which recognize self-antigens with high affinity are deleted. However, this deletion process is not perfect and not all autoreactive T cells are destroyed. When the distinction between self and non-self fails, tolerance breaks and the immune system attacks the host s own tissues. This results in autoimmunity. Regulatory T cells contribute to the maintenance of self-tolerance. They can actively suppress the function of autoreactive cells. Several populations of cells with regulatory properties have been described, but the best characterized population is the natural regulatory T cells (Treg cells), which develop in the thymus and express the transcription factor FOXP3. The thymic development of Treg cells in humans is the subject of this thesis. Thymocytes at different developmental stages were analyzed using flow cytometry. The CD4-CD8- double-negative (DN) thymocytes are the earliest T cell precursors in the T cell lineage. My results show that the Treg cell marker FOXP3 is up-regulated already in a subset of these DN thymocytes. FOXP3+ cells were also found among the more mature CD4+CD8+ double-positive (DP) cells and among the CD4+ and CD8+ single-positive (SP) thymocytes. The different developmental stages of the FOXP3+ thymocytes were isolated and their gene expression examined by quantitative PCR. T cell receptor (TCR) repertoire analysis was used to compare these different thymocyte populations. My data show that in humans commitment to the Treg cell lineage is an early event and suggest that the development of Treg cells follows a linear developmental pathway, FOXP3+ DN precursors evolving through the DP stage to become mature CD4+ Treg cells. Most T cells have only one kind of TCR on their cell surface, but a small fraction of cells expresses two different TCRs. My results show that the expression of two different TCRs is enriched among Treg cells. Furthermore, both receptors were capable of transmitting signals when bound by a ligand. By extrapolating flow cytometric data, it was estimated that the majority of peripheral blood Treg cells are indeed dual-specific. The high frequency of dual-specific cells among human Treg cells suggests that dual-specificity has a role in directing these cells to the Treg cell lineage. It is known that both genetic predisposition and environmental factors influence the development of autoimmunity. It is also known that the dysfunction or absence of Treg cells leads to the development of autoimmune manifestations. APECED (autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy) is a rare monogenic autoimmune disease, caused by mutations in the AIRE gene. In the absence of AIRE gene product, deletion of self-specific T cells is presumably disturbed and autoreactive T cells escape to the periphery. I examined whether Treg cells are also affected in APECED. I found that the frequency of FOXP3+ Treg cells and the level of FOXP3 expression were significantly lower in APECED patients than in controls. Additionally, when studied in cell cultures, the suppressive capacity of the patients' Treg cells was impaired. Additionally, repertoire analysis showed that the TCR repertoire of Treg cells was altered. These results suggest that AIRE contributes to the development of Treg cells in humans and the selection of Treg cells is impaired in APECED patients. In conclusion, my thesis elucidates the developmental pathway of Treg cells in humans. The differentiation of Tregs begins early during thymic development and both the cells dual-specificity and AIRE probably affect the final commitment of Treg cells.

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Two prerequisites for realistically embarking upon an eradication programme are that cost-benefit analysis favours this strategy over other management options and that sufficient resources are available to carry the programme through to completion. These are not independent criteria, but it is our view that too little attention has been paid to estimating the investment required to complete weed eradication programmes. We deal with this problem by using a two-pronged approach: 1) developing a stochastic dynamic model that provides an estimation of programme duration; and 2) estimating the inputs required to delimit a weed incursion and to prevent weed reproduction over a sufficiently long period to allow extirpation of all infestations. The model is built upon relationships that capture the time-related detection of new infested areas, rates of progression of infestations from the active to the monitoring stage, rates of reversion of infestations from the monitoring to active stage, and the frequency distribution of time since last detection for all infestations. This approach is applied to the branched broomrape (Orobanche ramosa) eradication programme currently underway in South Australia. This programme commenced in 1999 and currently 7450 ha are known to be infested with the weed. To date none of the infestations have been eradicated. Given recent (2008) levels of investment and current eradication methods, model predictions are that it would take, on average, an additional 73 years to eradicate this weed at an average additional cost (NPV) of $AU67.9m. When the model was run for circumstances in 2003 and 2006, the average programme duration and total cost (NPV) were predicted to be 159 and 94 years, and $AU91.3m and $AU72.3m, respectively. The reduction in estimated programme length and cost may represent progress towards the eradication objective, although eradication of this species still remains a long term prospect.

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Ozone (O3) is a reactive gas present in the troposphere in the range of parts per billion (ppb), i.e. molecules of O3 in 109 molecules of air. Its strong oxidative capacity makes it a key element in tropospheric chemistry and a threat to the integrity of materials, including living organisms. Knowledge and control of O3 levels are an issue in relation to indoor air quality, building material endurance, respiratory human disorders, and plant performance. Ozone is also a greenhouse gas and its abundance is relevant to global warming. The interaction of the lower troposphere with vegetated landscapes results in O3 being removed from the atmosphere by reactions that lead to the oxidation of plant-related components. Details on the rate and pattern of removal on different landscapes as well as the ultimate mechanisms by which this occurs are not fully resolved. This thesis analysed the controlling processes of the transfer of ozone at the air-plant interface. Improvement in the knowledge of these processes benefits the prediction of both atmospheric removal of O3 and its impact on vegetation. This study was based on the measurement and analysis of multi-year field measurements of O3 flux to Scots pine (Pinus sylvestris L.) foliage with a shoot-scale gas-exchange enclosure system. In addition, the analyses made use of simultaneous CO2 and H2O exchange, canopy-scale O3, CO2 and H2O exchange, foliage surface wetness, and environmental variables. All data was gathered at the SMEAR measuring station (southern Finland). Enclosure gas-exchange techniques such as those commonly used for the measure of CO2 and water vapour can be applied to the measure of ozone gas-exchange in the field. Through analysis of the system dynamics the occurring disturbances and noise can be identified. In the system used in this study, the possible artefacts arising from the ozone reactivity towards the system materials in combination with low background concentrations need to be taken into account. The main artefact was the loss of ozone towards the chamber walls, which was found to be very variable. The level of wall-loss was obtained from simultaneous and continuous measurements, and was included in the formulation of the mass balance of O3 concentration inside the chamber. The analysis of the field measurements in this study show that the flux of ozone to the Scots pine foliage is generated in about equal proportions by stomatal and non-stomatal controlled processes. Deposition towards foliage and forest is sustained also during night and winter when stomatal gas-exchange is low or absent. The non-stomatal portion of the flux was analysed further. The pattern of flux in time was found to be an overlap of the patterns of biological activity and presence of wetness in the environment. This was seen to occur both at the shoot and canopy scale. The presence of wetness enhanced the flux not only in the presence of liquid droplets but also during existence of a moisture film on the plant surfaces. The existence of these films and their relation to the ozone sinks was determined by simultaneous measurements of leaf surface wetness and ozone flux. The results seem to suggest ozone would be reacting at the foliage surface and the reaction rate would be mediated by the presence of surface wetness. Alternative mechanisms were discussed, including nocturnal stomatal aperture and emission of reactive volatile compounds. The prediction of the total flux could thus be based on a combination of a model of stomatal behaviour and a model of water absorption on the foliage surfaces. The concepts behind the division of stomatal and non-stomatal sinks were reconsidered. This study showed that it is theoretically possible that a sink located before or near the stomatal aperture prevents or diminishes the diffusion of ozone towards the intercellular air space of the mesophyll. This obstacle to stomatal diffusion happens only under certain conditions, which include a very low presence of reaction sites in the mesophyll, an extremely strong sink located on the outer surfaces or stomatal pore. The relevance, or existence, of this process in natural conditions would need to be assessed further. Potentially strong reactions were considered, including dissolved sulphate, volatile organic compounds, and apoplastic ascorbic acid. Information on the location and the relative abundance of these compounds would be valuable. The highest total flux towards the foliage and forest happens when both the plant activity and ambient moisture are high. The highest uptake into the interior of the foliage happens at large stomatal apertures, provided that scavenging reactions located near the stomatal pore are weak or non-existent. The discussion covers the methodological developments of this study, the relevance of the different controlling factors of ozone flux, the partition amongst its component, and the possible mechanisms of non-stomatal uptake.

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The aim of this thesis was to study the basic relationships between thinning and fertilisation, tree growth rate and wood properties of Norway spruce (Picea abies (L.) Karst.) throughout a stand rotation. The material consisted of a total of 109 trees from both long-term thinning (Heinola, 61°10'N, 26°01'E; Punkaharju, 61°49'N, 29°19'E) and fertilisation-thinning experiments (Parikkala, 61°36'N, 29°22'E; Suonenjoki, 62°45'N, 27°00'E) in Finland. Wood properties, i.e., radial increment, wood density, latewood proportion, tracheid length, cell wall thickness and lumen diameter, as well as relative lignin content, were measured in detail from the pith to the bark, as well as from the stem base towards the stem apex. Intensive thinning and fertilisation treatments of Norway spruce stands increased (8% 64%) the radial increment of studied trees at breast height (1.3 m). At the same time, a faster growth rate slightly decreased average wood density (2% 7%), tracheid length (0% 9%) and cell wall thickness (1% 17%). The faster growth resulted in only small changes (0% 9%) in lumen diameter and relative lignin content (1% 2%; lignin content was 25.4% 26%). However, the random variation in wood properties was large both between and within trees and annual rings. The results of this thesis indicate that the prevailing thinning and fertilisation treatments of Norway spruce stands in Fennoscandia may significantly enhance the radial increment of individual trees, and cause only small or no detrimental changes in wood and tracheid properties.

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Old trees growing in urban environments are often felled due to symptoms of mechanical defects that could be hazardous to people and property. The decisions concerning these removals are justified by risk assessments carried out by tree care professionals. The major motivation for this study was to determine the most common profiles of potential hazard characteristics for the three most common urban tree genera in Helsinki City: Tilia, Betula and Acer, and in this way improve management practices and protection of old amenity trees. For this research, material from approximately 250 urban trees was collected in cooperation with the City of Helsinki Public Works Department during 2001 - 2004. From the total number of trees sampled, approximately 70% were defined as hazardous. The tree species had characteristic features as potential hazard profiles. For Tilia trees, hollowed heartwood with low fungal activity and advanced decay caused by Ganoderma lipsiense were the two most common profiles. In Betula spp., the primary reason for tree removal was usually lowered amenity value in terms of decline of the crown. Internal cracks, most often due to weak fork formation, were common causes of potential failure in Acer spp. Decay caused by Rigidoporus populinus often increased the risk of stem breakage in these Acer trees. Of the decay fungi observed, G. lipsiense was most often the reason for the increased risk of stem collapse. Other fungi that also caused extensive decay were R. populinus, Inonotus obliquus, Kretzschmaria deusta and Phellinus igniarius. The most common decay fungi in terms of incidence were Pholiota spp., but decay caused by these species did not have a high potential for causing stem breakage, because it rarely extended to the cambium. The various evaluations used in the study suggested contradictions in felling decisions based on trees displaying different stages of decay. For protection of old urban trees, it is crucial to develop monitoring methods so that tree care professionals could better analyse the rate of decay progression towards the sapwood and separate those trees with decreasing amounts of sound wood from those with decay that is restricted to the heartwood area.

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1. The low density lipoprotein receptor is an important regulator of serum cholesterol which may have implications for the development of both hypertension and obesity. In this study, genotypes for a low density lipoprotein receptor gene (LDLR) dinucleotide polymorphism were determined in both lean and obese normotensive populations. 2. In previous cross-sectional association studies an ApaLI and a HincII polymorphism for LDLR were shown to be associated with obesity in essential hypertensives. However, these polymorphisms did not show an association with obesity in normotensives. 3. In contrast, this study reports that preliminary results for an LDLR microsatellite marker, located more towards the 3' end of the gene, show a significant association with obesity in the normotensive population studied. These results indicate that LDLR could play an important role in the development of obesity, which might be independent of hypertension.

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Preputial prolapse is an obvious condition affecting bulls from many breeds. Unfortunately, the losses in production and welfare concerns associated with preputial prolapse can remain undetected for long periods of time in the extensive beef areas of northern Australia where the bulls are not inspected regularly. Thus, there is a critical need to identify the structural factors predisposing to preputial prolapse in young bulls so that they can be culled early. Despite there being no firm scientific evidence of an association between preputial eversion and preputial prolapse, it seems logical that the increased exposure of the sensitive prepuce as a consequence of preputial eversion may increase the risk of bulls developing preputial pathology, in particular preputial prolapse. This may be particularly relevant in Bos indicus bulls as they have a more pendulous sheath and thus eversion of the prepuce may be associated with a greater risk of injury to the prepuce compared to that in Bos taurus bulls. Further, studies of preputial eversion in Bos taurus bulls have concluded that there is an association between polledness and increased prevalence and severity (length of everted prepuce and duration of eversion) of preputial eversion due primarily to the absence or poor development of the caudal preputial muscles. No similar definitive work in Bos indicus bulls has been conducted and thus anatomical studies reported in this thesis were conducted to determine if a similar association occurred in Bos indicus bulls. A survey of a sample of large beef breeding herds in northern Australia found that preputial prolapse is a significant problem in Bos indicus and Bos indicus derived bulls and affected both young and older bulls. The importance of preputial prolapse confirmed the value of further research into the causes of this problem. A series of anatomical studies confirmed that preputial eversion in Bos indicus derived bulls was not more prevalent in polled bulls than horned bulls and was not associated with deficiency of the caudal preputial muscles as was established in Bos taurus bulls. An anatomical study of Bos indicus derived bulls with preputial prolapse found that preputial prolapse occurred in horned bulls of varying ages and these bulls did not have any evidence of deficiency in the caudal preputial muscles. However, preputial prolapse was observed in young polled bulls that had poorly developed or absent caudal preputial muscles. It was concluded that deficiency of the caudal preputial muscles in polled Bos indicus derived bulls may predispose to preputial prolapse at an early age, but no predisposing anatomical factors were found for horned Bos indicus derived bulls. In these studies, preputial eversion and preputial prolapse were found in horned Bos indicus derived bulls that did not have any preputial muscle deficiency and it was noted that preputial eversion was not related to the length of the prepuce. Further studies confirmed that preputial eversion was linearly and consistently associated with position of the glans penis within the sheath in Bos indicus derived bulls, and movement of the glans penis towards the preputial orifice consistently resulted in preputial eversion in these bulls. A method to objectively measure the relationship between movement of the glans penis within the sheath and preputial eversion was developed. Studies in humans have linked function of some abdominal muscles to function of the pelvic organs. This relationship was investigated in Bos indicus derived bulls to determine whether the function of specific abdominal muscles affected position of the penis in the sheath. Using the method developed to objectively measure the relationship between penis movement and preputial eversion, the abdominal muscles that potentially were associated with movement of the glans penis or preputial eversion were examined but no significant relationships were observed. In the anatomical study of Bos indicus derived bulls not affected with preputial prolapse a more pendulous sheath was associated with increased prevalence of preputial eversion. This relationship was confirmed for horned and polled bulls in the penis movement studies. Bos indicus derived bulls with more pendulous sheaths evert their prepuces more than bulls with less pendulous sheaths thus increasing the risk of damage to the prepuce either from the environment, other bulls, or from them inadvertently stepping on the everted prepuce when they get to their feet. Culling Bos indicus derived bulls with more pendulous sheaths should reduce the incidence of preputial eversion and possibly preputial prolapse. The anatomical study of Bos indicus derived bulls that did not have preputial prolapse demonstrates that there are herds of bulls where the polled bulls do not have any evidence of deficiency of the caudal preputial iv muscles. There is a need to develop a practical and cost effective test to identify polled Bos indicus bulls that have a deficiency in their caudal preputial muscles.

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Targets for improvements in water quality entering the Great Barrier Reef (GBR) have been set through the Reef Water Quality Protection Plan (Reef Plan). To measure and report on progress towards the targets set a program has been established that combines monitoring and modelling at paddock through to catchment and reef scales; the Paddock to Reef Integrated Monitoring, Modelling and Reporting Program (Paddock to Reef Program). This program aims to provide evidence of links between land management activities, water quality and reef health. Five lines of evidence are used: the effectiveness of management practices to improve water quality; the prevalence of management practice adoption and change in catchment indicators; long-term monitoring of catchment water quality; paddock & catchment modelling to provide a relative assessment of progress towards meeting targets; and finally marine monitoring of GBR water quality and reef ecosystem health. This paper outlines the first four lines of evidence. (C) 2011 Elsevier Ltd. All rights reserved.

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Experiments were conducted over 5 years to understand the seasonal phenology of bare-rooted ?Festival? strawberry plants (Fragaria ?ananassa) growing at Nambour in southeastern Queensland, Australia. Yields ranged from 661 to 966 g/plant, and average seasonal fruit fresh weight ranged from 15 to 18 g. The growth of the leaves, crowns, roots, flowers and fruit over time followed a linear or sigmoid pattern. Maximum values of leaf, crown and root dry weight towards the end of the growing season about 190 days after planting were 30, 15 and 7 g/plant, respectively. The rates of leaf and crown growth were lower than those achieved in California under a Mediterranean climate. There were strong relationships between the allocation of dry matter to the leaves, crowns and roots and plant dry weight. Allocation to the leaves, and especially to the crowns and roots, declined as the plants grew. The number of fruit/plant increased initially over time with a decline later in the season. Average fruit fresh weight was generally higher early in the season and then declined as fruit production increased. There were strong relationships between the growth of the whole plant and the growth of the flowers and immature fruit, and leaf expansion, across the growing season and across the 5 different years. These results indicate that seasonal growth and potential productivity were strongly linked to the expansion of the leaves in this environment.

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Signed and titled lower center, with a dedication to the LeoBaeck Institute, dated 1961.

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Historical sediment nutrient concentrations and heavy-metal distributions were studied in five embayments in the Gulf of Finland and an adjacent lake. The main objective of the study was to examine the response of these water bodies to temporal changes in human activities. Sediment cores were collected from the sites and dated using 210Pb and 137Cs. The cores were analyzed for total carbon (TC), total nitrogen (TN), total phosphorus (TP), organic phosphorus (OP), inorganic phosphorus (IP), biogenic silica (BSi), loss on ignition (LOI), grain size, Cu, Zn, Al, Fe, Mn, K, Ca, Mg and Na. Principal component analysis (PCA) was used to summarize the trends in the geochemical variables and to compare trends between the different sites. The links between the catchment land use and sediment geochemical data were studied using a multivariate technique of redundancy analysis (RDA). Human activities produce marked geochemical variations in coastal sediments. These variations and signals are often challenging to interpret due to various sedimentological and post-depositional factors affecting the sediment profiles. In general, the sites studied here show significant upcore increases in sedimentation rates, TP and TN concentrations. Also Cu, which is considered to be a good indicator of anthropogenic influence, showed clear increases from 1850 towards the top part of the cores. Based on the RDA-analysis, in the least disturbed embayments with high forest cover, the sediments are dominated by lithogenic indicators Fe, K, Al and Mg. In embayments close to urban settlement, the sediments have high Cu concentrations and a high sediment Fe/Mn ratio. This study suggests that sediment accumulation rates vary significantly from site to site and that the overall sedimentation can be linked to the geomorphology and basin bathymetry, which appear to be the major factors governing sedimentation rates; i.e. a high sediment accumulation rate is not characteristic either to urban or to rural sites. The geochemical trends are strongly site specific and depend on the local geochemical background, basin characteristics and anthropogenic metal and nutrient loading. Of the studied geochemical indicators, OP shows the least monotonic trends in all studied sites. When compared to other available data, OP seems to be the most reliable geochemical indicator describing the trophic development of the study sites, whereas Cu and Zn appear to be good indicators for anthropogenic influence. As sedimentation environments, estuarine and marine sites are more complex than lacustrine basins with multiple sources of sediment input and more energetic conditions in the former. The crucial differences between lacustrine and estuarine/coastal sedimentation environments are mostly related to Fe. P sedimentation is largely governed by Fe redox-reactions in estuarine environments. In freshwaters, presence of Fe is clearly linked to the sedimentation of other lithogenic metals, and therefore P sedimentation and preservation has a more direct linkage to organic matter sedimentation.

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In Finland, peat harvesting sites are utilized down almost to the mineral soil. In this situation the properties of mineral subsoil are likely to have considerable influence on the suitability for the various after-use forms. The aims of this study were to recognize the chemical and physical properties of mineral subsoils possibly limiting the after-use of cut-over peatlands, to define a minimum practice for mineral subsoil studies and to describe the role of different geological areas. The future percentages of the different after-use forms were predicted, which made it possible to predict also carbon accumulation in this future situation. Mineral subsoils of 54 different peat production areas were studied. Their general features and grain size distribution was analysed. Other general items studied were pH, electrical conductivity, organic matter, water soluble nutrients (P, NO3-N, NH4-N, S and Fe) and exchangeable nutrients (Ca, Mg and K). In some cases also other elements were analysed. In an additional case study carbon accumulation effectiveness before the intervention was evaluated on three sites in Oulu area (representing sites typically considered for peat production). Areas with relatively sulphur rich mineral subsoil and pool-forming areas with very fine and compact mineral subsoil together covered approximately 1/5 of all areas. These areas were unsuitable for commercial use. They were recommended for example for mire regeneration. Another approximate 1/5 of the areas included very coarse or very fine sediments. Commercial use of these areas would demand special techniques - like using the remaining peat layer for compensating properties missing from the mineral subsoil. One after-use form was seldom suitable for one whole released peat production area. Three typical distribution patterns (models) of different mineral subsoils within individual peatlands were found. 57 % of studied cut-over peatlands were well suited for forestry. In a conservative calculation 26% of the areas were clearly suitable for agriculture, horticulture or energy crop production. If till without large boulders was included, the percentage of areas suitable to field crop production would be 42 %. 9-14 % of all areas were well suitable for mire regeneration or bird sanctuaries, but all areas were considered possible for mire regeneration with correct techniques. Also another 11 % was recommended for mire regeneration to avoid disturbing the mineral subsoil, so total 20-25 % of the areas would be used for rewetting. High sulphur concentrations and acidity were typical to the areas below the highest shoreline of the ancient Litorina sea and Lake Ladoga Bothnian Bay zone. Also differences related to nutrition were detected. In coarse sediments natural nutrient concentration was clearly higher in Lake Ladoga Bothnian Bay zone and in the areas of Svecokarelian schists and gneisses, than in Granitoid area of central Finland and in Archaean gneiss areas. Based on this study the recommended minimum analysis for after-use planning was for pH, sulphur content and fine material (<0.06 mm) percentage. Nutrition capacity could be analysed using the natural concentrations of calcium, magnesium and potassium. Carbon accumulation scenarios were developed based on the land-use predictions. These scenarios were calculated for areas in peat production and the areas released from peat production (59300 ha + 15 671 ha). Carbon accumulation of the scenarios varied between 0.074 and 0.152 million t C a-1. In the three peatlands considered for peat production the long term carbon accumulation rates varied between 13 and 24 g C m-2 a-1. The natural annual carbon accumulation had been decreasing towards the time of possible intervention.