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260 Uppsatser om Stocking density - Sida 11 av 18

Kunskapsläge och attityder till vildsvin (Sus scrofa) och dess förvaltning i Sverige

The wild boar (Sus scrofa) is since its recent establishment and increasing density a controversial species in Sweden. But the attitudes towards the wild boar are poorly documented so far. To improve this knowledge, a questionnaire was sent out to chosen people (n=400) connected to the management and/or land use activities. The study got 162 replies (reply frequency 40,5%) and the results show varying attitude trends among organizations and individuals, with some aspects coherent within groups and some not. Farmers and their organization showed the most negative attitudes towards wild boars, which was expected due to the practical and economic problems they suffer from this species. People involved with forestry were more positive to wild boars, probably because the species does not affect forest growth etc severely, and may even promote plant establishment by the rooting.

Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna

The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.

Vegetationens roll i erosiva vattendrag : en review och fältstudie av två nyckelområden i Rönne å

The vegetation?s impact on erosion control is widely explored, even though research? results are scattered where it suggests a both positive and negative relationship between roots and erosion tendency. Research has measured the roots? impact on erosion by many different methods, hence the aim of this study is to offer a clearance of what factors play an important role in the choice of appropriate species controlling river bank erosion. I have therefore studied 17 articles concerning vegetation and erosion control, which were found in different databases such as: Web of Knowledge, Biological Sciences, Academic Search Elite and Google Scholar.

Marktillstånd och borbrist på åkermark planterad med gran i Västerbottens län :

This study was made on former agricultural areas that had been planted with spruce or pine, in the county of Västerbotten. The goal of the project was to investigate suspected deficiency of boron in these areas. Several objects have been reported for possible deficiency and some of these have the characteristic symptoms of boron-deficiency. The hypotheses are that 1) Boron deficiency is present at several of the investigated objects. 2) Planting of forest on cultivated postglacial sediments leads to a successive podzolisation with a decreasing content of organic matter in the mineral soil, due to decomposition, and a decreasing pH in the soil, even on locations that have been added lime. To be able to confirm or reject the hypotheses a number of tests were performed.

En undersökning om fallolyckor med gångtrafikanter

The purpose of this study was to investigate different relations between the damages of falls and background variables as well as the relation between the falls and the weather condition to later be able to use this report to expand the knowledge among workers at VTI about the pedestrian fall injuries. All of the fall injuries in the data that this study is based on have occurred in Sweden during the time period between January 2003 and December 2011.To be able to answer the questions that this report is based on several statistical methods are used. The statistical methods that have been used during the making of this report are multiple linear regression, binary logistic regression, correlation analysis, association analysis and descriptive statistics as well as visual analysis.The results of the study show that women around menopause age have a tendency to get a big increase in the amount of injuries compared to men of the same age. The study also suggests that men on average tend to have a lower level of injury compared to women.Age also seems to affect both the amount of injuries and the level of injury negatively. The study suggests that the most likely reason for this is both that the intake of ?Fall Risk Increasing Medicine?, which is medicine that increases the drowsiness, is higher among older individuals as well as lower estrogen levels among older women and lower amount of testosterone among older men, which causes a loss of bone density in both sexes.The weather seems to have a strong effect on how many injuries occur but also a noticeable effect on the scale of the injury.

Preventiva åtgärder mot osteoporos och osteoporosrelaterade frakturer

Osteoporos är en sjukdom som under de senaste decennierna ökat. I Sverige inträffar det cirka 70 000 osteoporosrelaterade benbrott varje år. Den största gruppen som drabbas är kvinnor efter menopaus. Syftet var att belysa faktorer som är av betydelse för prevention av osteoporos och osteoporosrelaterade frakturer hos postmenopausala kvinnor. Metoden var en systematisk litteraturstudie bestående av 10 vetenskapliga artiklar varav 9 baserade på kvantitativ och en på kvalitativ forskning.

Biologiska behandlingsmetoder för rening av rejektvatten från biogasproduktion

In this literature review the characteristics of two free-floating macrophytes, water hyacinth   (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.

DEN EKONOMISKA EFFEKTEN AV ÖVERKLAGANDEN I GÖTEBORG - Kan överklaganden mot bostadsbyggnadsprojekt härledas till demografiska faktorer och vilka ekonomiska effekter kan de ge för byggföretagen?

This bachelor thesis addresses the problem of appeals against house building in Gothenburg. The thesis investigates whether there is a statistically significant relationship between demographic factors and the occurrence of approved, appealed and revoked permits for new construction of residential buildings in the ten districts of Gothenburg. This is done with a correlation analysis. The report also investigates whether there is a statistically significant regression in the same demographic factors and how these individually affect the average processing time for appeals in the districts. This study is done with a multiple regression analysis.

En jämförelse avseende beståndsgående-och stickvägsgående gallringsmaskiner

The purpose of this report is to investigate and compare the difference between stand-thinning machines and strip-road thinning machines, and how they affect the stand on behalf of future growth, theoretical economic result, wind impact, snow pressure and density of stand. The investigation is regarding the first commercial thinning of pine stands, after pre-commercial thinning that was well conducted. The investigation area was located near Katrineholm, Sweden. The measurements that were measured were strength of thinning and amounts of wind throws, snow-breaks and hauling damages. The results that emerged, was that thinning with strip-road machines had a significantly higher strength of thinning over all, as compared with the stand- thinning machines (45 percent versus 30 percent). Comparisons between wind-throws, snow-breaks and hauling damages of the stand could not establish any significant differences between the two methods that were investigated. Conclusions, over all, were that if forest owners want to have more timber volume left for second thinning and final cut of the stand, the forest owners should choose the method with stand-thinning machines. From the point of view of gentle treatment of the stand and ground damages the choice should be the same. However, the method with strip-road thinning machines is the most common and accessible method in Sweden. Most likely it is the most economical way to manage the stand for forest owners in present time. If the method with stand-thinning machines is becoming more common in Sweden, it is suggested for forest owners to consider the stand-thinning method as a candidate for treatment due to economic aspects..

Hunter demography, trends and correlates of hunting participation in Sweden

The concerning issue of declining number of hunters in North America is also apparent in Europe and Sweden. When the bulk of research found on human dimensions and hunting participation has almost exclusively been done in the United States, this report seeks to add to the needed knowledge on a national level focusing on the causes of hunter declines related to social factors within Sweden. Using hunter data reaching from commune, county to National level, this report describes the correlation between a number of variables and the hunting participation in Sweden.The typical Swedish hunter lives in an area with low population density, the person usually has higher education, the living situation is stable with no recent moving and there is relatively good access to forest land. Persons with weaker connection to the Swedish culture such as foreign citizens, people with foreign background and people born outside ?the Nordic countries? are less likely to start hunt or participate in hunting.A strong relationship was found between the favorite game, moose (Alces alces), and the amount of hunters participating in the hunting.

Påverkas mosippa (Pulsatilla vernalis) negativt av igenväxning?

Pulsatilla vernalis is one of several endangered plant species that benefit from wildfires and small scale disturbance events that repel competing vegetation and create open patches in the vegetation cover. Previous studies argue that Pulsatilla vernalis is decreasing in numbers due to vegetation changes associated with the decrease in wildfires, forest grazing and changes in forest management. In this study, 17 populations of P. vernalis were inventoried in order to examine if soil and/or vegetation structures affect the population structure of P. vernalis (i.e.

Beräkning av direktljud genom homogena betongväggar : Densitetens och tjocklekens påverkan på reduktionstalet

Today's urban centers become denser, which contributes to higher demands on sound and noise. It is therefore highly relevant to build homes with good sound environment while maintaining living space. This thesis aimed to reduce the current concrete walls and see how the mass law affects the reduction index value and flanking transmissions. Handmade calculations were calculated according to the Swedish standard SS-EN 21354-1, where only air sound was calculated.Calculations we­­­re performed on wall elements with different weights and thicknesses, and compared with results from Bastian.In Bastian calculations of flanking transmissions were also made, this was made to see the impact of the flanking transmission when changing the mass per unit area. Mass law's impact was examined by flanking transmission and the result shows that they are not affected as long as the ratio between the thickness and the density remains the same.A questionnaire survey was conducted to determine the actual sound experience; this questionnaire was conducted on three concrete buildings in Växjö.

Stockholms förtätningsideal i strävan mot hållbar stadsutveckling : En studie om sambanden mellan den täta staden och Stockholms parker och offentliga grönområden

Syftet med denna studie är att undersöka sambandet mellan Stockholms parker och offentliga grönområdena i relation till den rådande förtätning staden genomför. Stockholm har en tydlig strategi på att skapa en tät stad vilket medför effekter på stadens parker och offentliga grönområden. Studien diskuterar de värden som tillkommer och går förlorade när exploateringen av staden ökar samtidigt som den totala arealen grönområden minskar. Vidare diskuteras det offentliga grönområdenas funktion i den täta staden. De metoder som använts i studien består av semistrukturerade informantintervjuer i kombination med telefon- och e-postintervjuer följt av en bred litteraturundersökning.

The distribution of Moose (Alces alces) during winter in southern Sweden : a response to food sources?

The traditional Swedish way of dealing with browsing damages made by moose, is to reduce the moose population. However, a growing way of dealing with damages made by several ungulate species, including wild boars in particular is to redistribute them with supplementary food sources. Attracting them to settle in habitats less vulnerable to damages made during foraging. This study we tracked collared moose in southern Sweden from January throughout April in the year of 2009. From the tracking data their ?favourite? positions was selected and visited in order to study the features that attracts moose during winter.

A risk analysis of moose close to roads

For many decades the increase in traffic volume, expansion of highways and infrastructure has lead to an increase of wildlife vehicle collisions which are unfortunately very common in many countries today. They cause great deal of material damage and even kill humans or wildlife. Measures in the form of warning signs, under- and overpasses and fencing have been implemented for a long time with the help of observation by hunters and collisions sites. However this study focuses on the moose?s perspective and the variables that, both spatially and temporally, could have an effect on why and when moose are close to certain types of roads.

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