Sök:

Sökresultat:

9211 Uppsatser om Soil analysis - Sida 14 av 615

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.

Var är brudarna? : En innehållsanalytisk studie om kvinnliga idrottsutövare i Sportbladet

The goal with our research has been to describe how often and in what way female athletes are represented in the sport section in Sweden?s biggest evening newspaper Aftonbladet. The material we?ve used are the newspapers that we collected during two weeks in 2008, the 3rd of November to the 9th of November and the 11th of November to the 17th of November. We?ve conduced two qualitative researches ? a text analysis and an image analysis ? and one quantitative analysis on our material.

Plan för multifunktionella buffertzoner längs Vramsån på Malörten AB: s jordbruksfastigheter

To create multifunctional buffer strips along a watercourse in an economically sustainable way requires consideration of many different factors. In this plan we have selected pollutant reduction as the main purpose of the buffer strip. We have also strived to achieve minimal income loss due to reduced production, increased biological diversity, good game preservation that leads to higher income from hunting, aesthetical satisfaction and possibility to profit from available subsidies. This is done mainly to make landowners/farmers more interested in creating buffer strips along water courses. As sand is the dominant type of soil in the area, the water course is less affected by surface runoff compared to if the soil would be clay or some other finer texture. Game preservation and subsidies have therefore been the main factors when establishing the width of the strip, because these require wider buffer strips in some cases.

Lodgepole pine - stability after thinning

SCA has today almost 300 000 hectares of their forest land planted with lodgepole pine(Pinus contorta var. latifolia). Due to initial extensive planting in the 1970ies the area oflodgepole pine forests in the thinning age has grown rapidly from the end of the 1990ies.During the years 1996-2005 first commercial thinning of lodgepole pine at SCA took place.The goal of the hereby presented study was to investigate the growth and stability in thosefirstly-thinned lodgepole pine stands a few years after thinning. Furthermore, the objectivewas to investigate the relationship between stand stability and different stand parameters.Additionally, lodgepole pine stem quality was estimated.The study is mainly based on the data collected during an inventory project carried out atSCA in 2008. Altogether 91 lodgepole pine stands in northern Sweden were measured afterthe first thinning.

Naturlig nedbrytning av klorerade lösningsmedel i grundvatten

Chlorinated solvents are common contaminants in soil and water. Under anaerobic conditions microbes are capable of transforming chlorinated solvents into ethylene which would result in a remediation of the contaminated area. In order to use natural attenuation as a remediation method evidence of continuous degradation is required. Furthermore, the degradation must occur at a sufficient rate and continuous monitoring of the site is needed until the demanded levels are achieved. A field study was performed on the basis of data from a dry-cleaning facility contaminated mainly by perchloroethylene.

Fodder to ruminants within agroforestry systems in Rwanda - species and management

Rwanda is one of the poorest countries in the world and about 70-80 % of the population lives in rural areas. The land is strongly affected by land erosion which makes it difficult for the agriculture and food production. Agroforestry is a system where tree plantation is combined with livestock- and crop production. The system provides soil fertilization and binds the soil together. Some of the trees used in agroforestry systems are also used as fodder.

Länkanalys: En undersökning av ett biblioteks- och informationsvetenskapligt delfält

The aim of this study is to analyse and investigate a rather new field of LIS studies, i.e. link analysis which is a part of webometrics. Webometrics has been described as the quantitative study of web based phenomena drawing on bibliometric or informetric methods. Link analysis has its counterpart in citation analysis within the field of bibliometrics. The questions the study investigates are if webometrics can provide LIS with new knowledge and if there is a place for webometric studies in LIS research.

Svamparnas roller i svenska barrskogsekosystem : hur ser kunskapsläget ut hos några olika grupper människor?

Fungi are everywhere around us and recently, there has been an increased interest in their role and importance in the forest. The fungi have several strategies to acquire energy and nutrition; one example is a mutual symbiosis with trees and plants - another being dissolving organic materials. Attempts have been made to better understand the circulation of nutrition in coniferous forests, and how fungi cooperate. Trees and plants have adapted with mycorrhizae and are now interdependent which is important to consider in forestry. A great number of fungi depend on dead wood and old trees to set fruiting bodies and spread further. These fungi also create environments for other species, such as birds and insects. The vegetation of a forest is determined by a series of factors; tree species, how old the forest is, soil type, as well as the ability of the fungal spores to spread and establish. Furthermore, in determining vegetation, the fungi?s ability to compete in the soil matters. These factors are nearly unexplored. Researching fungi knowledge and interest, a survey was distributed to five groups of people. The groups included forest owners, high school teachers, high school students, senior citizens, and a fifth group - ?o he ? - consisting of people of mixed ages and backgrounds.

Design av utomhusträdgård i Dubai :

To plan and build a garden in Dubai has other conditions and challenges than what you experience in Sweden. The heat, wind and lack of water makes the need for durable plants, a good design and landscaping important if you want to have the opportunity to use your garden during most of the year. The soil is poor of nutrients, alkaline and sometimes saline, witch makes supplying the soil with organic material and various fertilizers necessary if you want to be able to plant a bigger range of plant material in your garden. Another important part is to provide your garden with a good irrigation system that should be put into the ground before planting so that the plants are given a more even irrigation. It?s relatively green scenery you meet and to me it?s in a way surprising since the country with its climate is rather harsh for the purpose of supporting plant life.

Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project

The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations. The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.

Controlled traffic for grass silage production : an economic evaluation for dairy farmers

The farm management system controlled traffic farming (CTF) aims to reduce soil compaction by restricting the field traffic from agricultural machinery to permanent traffic lanes. Literature and empirical findings show that soil compaction and field traffic from heavy machinery may affect crop growth negatively, reducing crop yields. If grass-clover leys are subject to heavy field traffic the botanic composition might be altered, providing a lower clover content in the forage. Clover as a silage feed is rich in protein providing good conditions for high yielding dairy cows. Grass-clover silage production is generally associated with intensive field traffic.

Ökad kollagring i boreal skog : Kan blädningsbrukad skog lagra mer kol än trakthyggesbrukad skog?

This study was conducted to test the hypotheses that a forest managed by selective cutting can store more carbon than a forest managed by clearcutting. The study was carried out as a meta-analysis. The data that was found was analyzed by performing t-tests on the proportional effect that the two silvicultural methods had on the driving factors of CO2-efflux and carbon stores in coniferous boreal forest. In all areas tested, an effect in favor of selective cutting was found, but not all of them significant however. The soil respiration following selective cutting was significantly lower than that of clearcutting, and the primary production of a clearcut area cannot according to reason exceed that of an area post-selective cutting.

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.

Avfallsdirektivets påverkan på efterbehandling av förorenad mark

The purpose of this report is to increase the awareness about the problem that occur when the waste hierarchy is applied to management of contaminated land. The work with remediation of contaminated land in Sweden is part of the efforts towards reaching the national environmental objectives. Therefore a subsidiary aim is to analyze how this influences the prospects of reaching the objectives. The work consists of two parts; a case study and a comparative literature study that focus on England, the Netherlands and Sweden. The case study is intended to provide a practical perspective through a comparison of the climate impact from two methods.

Den ena boplatsvallen är den andra lik? : Miljöarkeologisk intra-site studie av boplatsvallar vid Lillsjön, Anundsjö sn., Ångermanland

Boplatsvallar, often translated as semi-subterranean settlements, is an ancient monument with a diffuse definition. Defined as ?embankments that partially or completely surround a often lowered/dug down surface- this category of ancient monuments is also made up of a former category which traditionally was interpreted as winter settlements from the late Stone age in Sweden. This view of the ancient monuments carried over, to a certain extent, to this new definition. Should this be the case, that this category of ancient monuments are remains of winter settlements,  used recurringly over an extended period of time, then they should exhibit similar signals in regards to the distribution of the anthropogenically altered soil chemical and soil physical properties at the sites.The area around Lillsjön, Anundsjö parish in Ångermanland, have four boplatsvallar located separately in the regional area.

<- Föregående sida 14 Nästa sida ->