5 resultados para no-take zones
em Helda - Digital Repository of University of Helsinki
Resumo:
The aim of this research is to study the boundary zone of home and work and the tensions people experience while reconciling home and work? How are the requirements of the family, the home and the work taken care of in everyday life? What kind of difficulties does the individual experience when reconciling home activities and job requirements together? What kind of activity policies have families created to ease the everyday life? What kind of goals and requirements do families feel behind the difficulties in adjusting home and work? What kind of changes would make the adjusting of home and work easier? The changing family life, everyday home activities and the changing Finnish working life are studied to describe the adjusting of home and work. In addition the boundary zone of home and work and its tensions are studied. 337 research persons who find reconciling home and work challenging were elected from different sectors of the working life. Research persons were gathered from the public, private and third sectors. The research material was gathered with a semi-structured qualitative questionnaire published in internet. Contents analysis was the analysis method of the research material. The tensions of adjusting home and work are various. Several activity systems meet on the boundary zone of home and work causing boundary zones to expand and tensions to increase and expand like a network. In the everyday life of an individual the boundary zone fades out and home and work overlap. Tensions can be examined as internal conflicts of the individual through the activity system of everyday life. Individuals balance between individualism and familism, feeling bad, suffering from lack of time and struggling with childcare organizing problems and inflexible employers. The solutions to reconciling home and work difficulties are situational. Often is the help of family and friends required without any solid solutions. The conflict of the goals, requirements and the reality is behind the problems as well as the tightening terms of the working life and its growing expectations. Change requests are proposed on the levels of individual, home, work and the society. Reconciling home and work is not only a challenge between the employee and the employer. It s a problem that needs multilateral solutions and changes on the levels of individual, home, work and society. The challenge remaining is to find out if it would be successful to take the everyday life as starting point to negotiate the reconciling of home and work and how the possible family, social and work political solutions appear in everyday life.
Resumo:
Phosphorus (P) retention properties of soils typical for boreal forest, i.e. podzolic soil and peat soils, vary significantly, but the range of this variation has not been sufficiently documented. To assess the usefulness of buffer zones used in forestry in removing P from the discharge by chemical sorption in soil, and to estimate the risk of P leaching after forestry operations, more data is needed on soil P retention properties. P retention properties of soils were studied at clear-cut areas, unharvested buffer zones adjoining the clear-cut and at peatland buffer zone areas. Desorption-sorption isotherms were determined for the humus layer, the mineral soil horizons E, B and C of the Podzol profile and for the surface layer peat (0-15 cm) and the subsurface layer peat (15-30 cm). The efficiency of buffer zones in retaining P was studied at six peatland buffer zone areas by adding P-containing solute in the inflow. A tracer study was conducted at one of the buffer zone areas to determine the allocation of the added P in soil and vegetation. Measured sorption or desorption rather than parameter values of fitted sorption equations described P desorption and sorption behaviour in soil. The highest P retention efficiency was in the B horizon and consequently, if contact occurred or was established between the soluble P in the water and the soil B horizon, the risk of P leaching was low. Humus layer was completely incapable of retaining P after clear-cutting. In the buffer zones, the decrease in P retention properties in the humus layer and the low amount of P sorbed by it indicated that the importance of the layer in the functioning of buffer zones is low. The peatland buffer zone areas were efficient in retaining soluble P from inflow. P sorption properties of the peat soil at the buffer zone areas varied largely but the contribution of P sorption in the peat was particularly important during high flow in spring, when the vegetation was not fully developed. Factors contributing to efficient P retention were large buffer size and low hydrological load whereas high hydrological load combined with the formation of preferential flow paths, especially during early spring or late autumn was disadvantageous. However, small buffer zone areas, too, may be efficient in reducing P load.
Resumo:
Buffer zones are vegetated strip-edges of agricultural fields along watercourses. As linear habitats in agricultural ecosystems, buffer strips dominate and play a leading ecological role in many areas. This thesis focuses on the plant species diversity of the buffer zones in a Finnish agricultural landscape. The main objective of the present study is to identify the determinants of floral species diversity in arable buffer zones from local to regional levels. This study was conducted in a watershed area of a farmland landscape of southern Finland. The study area, Lepsämänjoki, is situated in the Nurmijärvi commune 30 km to the north of Helsinki, Finland. The biotope mosaics were mapped in GIS. A total of 59 buffer zones were surveyed, of which 29 buffer strips surveyed were also sampled by plot. Firstly, two diversity components (species richness and evenness) were investigated to determine whether the relationship between the two is equal and predictable. I found no correlation between species richness and evenness. The relationship between richness and evenness is unpredictable in a small-scale human-shaped ecosystem. Ordination and correlation analyses show that richness and evenness may result from different ecological processes, and thus should be considered separately. Species richness correlated negatively with phosphorus content, and species evenness correlated negatively with the ratio of organic carbon to total nitrogen in soil. The lack of a consistent pattern in the relationship between these two components may be due to site-specific variation in resource utilization by plant species. Within-habitat configuration (width, length, and area) were investigated to determine which is more effective for predicting species richness. More species per unit area increment could be obtained from widening the buffer strip than from lengthening it. The width of the strips is an effective determinant of plant species richness. The increase in species diversity with an increase in the width of buffer strips may be due to cross-sectional habitat gradients within the linear patches. This result can serve as a reference for policy makers, and has application value in agricultural management. In the framework of metacommunity theory, I found that both mass effect(connectivity) and species sorting (resource heterogeneity) were likely to explain species composition and diversity on a local and regional scale. The local and regional processes were interactively dominated by the degree to which dispersal perturbs local communities. In the lowly and intermediately connected regions, species sorting was of primary importance to explain species diversity, while the mass effect surpassed species sorting in the highly connected region. Increasing connectivity in communities containing high habitat heterogeneity can lead to the homogenization of local communities, and consequently, to lower regional diversity, while local species richness was unrelated to the habitat connectivity. Of all species found, Anthriscus sylvestris, Phalaris arundinacea, and Phleum pretense significantly responded to connectivity, and showed high abundance in the highly connected region. We suggest that these species may play a role in switching the force from local resources to regional connectivity shaping the community structure. On the landscape context level, the different responses of local species richness and evenness to landscape context were investigated. Seven landscape structural parameters served to indicate landscape context on five scales. On all scales but the smallest scales, the Shannon-Wiener diversity of land covers (H') correlated positively with the local richness. The factor (H') showed the highest correlation coefficients in species richness on the second largest scale. The edge density of arable field was the only predictor that correlated with species evenness on all scales, which showed the highest predictive power on the second smallest scale. The different predictive power of the factors on different scales showed a scaledependent relationship between the landscape context and local plant species diversity, and indicated that different ecological processes determine species richness and evenness. The local richness of species depends on a regional process on large scales, which may relate to the regional species pool, while species evenness depends on a fine- or coarse-grained farming system, which may relate to the patch quality of the habitats of field edges near the buffer strips. My results suggested some guidelines of species diversity conservation in the agricultural ecosystem. To maintain a high level of species diversity in the strips, a high level of phosphorus in strip soil should be avoided. Widening the strips is the most effective mean to improve species richness. Habitat connectivity is not always favorable to species diversity because increasing connectivity in communities containing high habitat heterogeneity can lead to the homogenization of local communities (beta diversity) and, consequently, to lower regional diversity. Overall, a synthesis of local and regional factors emerged as the model that best explain variations in plant species diversity. The studies also suggest that the effects of determinants on species diversity have a complex relationship with scale.
Resumo:
The main objective of this study is to evaluate selected geophysical, structural and topographic methods on regional, local, and tunnel and borehole scales, as indicators of the properties of fracture zones or fractures relevant to groundwater flow. Such information serves, for example, groundwater exploration and prediction of the risk of groundwater inflow in underground construction. This study aims to address how the features detected by these methods link to groundwater flow in qualitative and semi-quantitative terms and how well the methods reveal properties of fracturing affecting groundwater flow in the studied sites. The investigated areas are: (1) the Päijänne Tunnel for water-conveyance whose study serves as a verification of structures identified on regional and local scales; (2) the Oitti fuel spill site, to telescope across scales and compare geometries of structural assessment; and (3) Leppävirta, where fracturing and hydrogeological environment have been studied on the scale of a drilled well. The methods applied in this study include: the interpretation of lineaments from topographic data and their comparison with aeromagnetic data; the analysis of geological structures mapped in the Päijänne Tunnel; borehole video surveying; groundwater inflow measurements; groundwater level observations; and information on the tunnel s deterioration as demonstrated by block falls. The study combined geological and geotechnical information on relevant factors governing groundwater inflow into a tunnel and indicators of fracturing, as well as environmental datasets as overlays for spatial analysis using GIS. Geophysical borehole logging and fluid logging were used in Leppävirta to compare the responses of different methods to fracturing and other geological features on the scale of a drilled well. Results from some of the geophysical measurements of boreholes were affected by the large diameter (gamma radiation) or uneven surface (caliper) of these structures. However, different anomalies indicating more fractured upper part of the bedrock traversed by well HN4 in Leppävirta suggest that several methods can be used for detecting fracturing. Fracture trends appear to align similarly on different scales in the zone of the Päijänne Tunnel. For example, similarities of patterns were found between the regional magnetic trends, correlating with orientations of topographic lineaments interpreted as expressions of fracture zones. The same structural orientations as those of the larger structures on local or regional scales were observed in the tunnel, even though a match could not be made in every case. The size and orientation of the observation space (patch of terrain at the surface, tunnel section, or borehole), the characterization method, with its typical sensitivity, and the characteristics of the location, influence the identification of the fracture pattern. Through due consideration of the influence of the sampling geometry and by utilizing complementary fracture characterization methods in tandem, some of the complexities of the relationship between fracturing and groundwater flow can be addressed. The flow connections demonstrated by the response of the groundwater level in monitoring wells to pressure decrease in the tunnel and the transport of MTBE through fractures in bedrock in Oitti, highlight the importance of protecting the tunnel water from a risk of contamination. In general, the largest values of drawdown occurred in monitoring wells closest to the tunnel and/or close to the topographically interpreted fracture zones. It seems that, to some degree, the rate of inflow shows a positive correlation with the level of reinforcement, as both are connected with the fracturing in the bedrock. The following geological features increased the vulnerability of tunnel sections to pollution, especially when several factors affected the same locations: (1) fractured bedrock, particularly with associated groundwater inflow; (2) thin or permeable overburden above fractured rock; (3) a hydraulically conductive layer underneath the surface soil; and (4) a relatively thin bedrock roof above the tunnel. The observed anisotropy of the geological media should ideally be taken into account in the assessment of vulnerability of tunnel sections and eventually for directing protective measures.
Resumo:
War children were sent away to shelter without their parents to other Nordic countries, mainly to Sweden. The phenomenon was remarkable. During the Second World War nearly 80,000 children were sent from their homes by trains or boats. These children travelled to foster homes where they were placed with new parents looking after them. After the conclusion of the peace, for some months or sometimes years later, orders were given to send the children back to their families in Finland. Returning back to Finland and to their biological parents and families was not always easy. Deep bonds between the children and their foster families were created and leaving caused grief to those small travellers once again. In some cases, distances were created in the relations between Mothers and their daughters. Many had forgotten their Finnish, and returning to school proved difficult. Some of the war children felt rootlessness, a result of being torn away from their family and culture. The aim of this study is to describe how former war children became mothers by themselves, and later on grandmothers. The study also explores how they describe the meaning of the war and their childhood in their own parenthood and what were their experiences of time in foster homes. Seven former war children and three daughters were interviewed for this study. Interviews were biographical. A narrative approach and thematic reading (by Riessman 2008) has guided the analysis of the texts. According to the results of this study, the importance of having your own home , family and security in childhood relationships is significant. Caring and having responsibility for disadvantaged others was important for former war children. What come from the detailed experiences of the 'war childhood' most of all were the difficulties they found on returning to Finland. Some of them had become very attached to their foster parents. There were varying degrees of language problems among the returnees. Some of the interviewees had completely forgotten their native language. Given that, starting the school at home was difficult. They also remembered continuous travelling.When asked on the outcome of their relationship with their biological mother, most interviewees were happy, with a few experiencing some distance in this relationship. Security and being available to protect their children were important in their own motherhood and grand motherhood. In difficult family situations like divorce, they wanted to give their time and support for helping with grandchildren. Another important aspect in family life is interaction between all its members. Talking things through in families and also in War Child Associations was highly valued. However, talking of war childhood had been silenced in some families. In conclusion, the experiences of former war children should take in consideration when difficult situations between parents and children or children s positions in war zones are resolved. War children also have a lot to give for further educational study.