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494 Uppsatser om Excavated soil - Sida 29 av 33

Konceptstudie av drivmodul till bandskotare med hybriddrift

BAE Systems Hägglunds has a long history of producing high performance terrain tracked vehicles (mostly for military applications), and they are now aiming at developing a tracked forwarder with similar techniques.The forwarder will be of series hybrid type where a diesel engine via a generator will power the motors (one for each drive wheel). Thanks to individually controlled motors and the gentle rubber tracks, this forwarder is calculated to have a considerably higher average speed in the terrain and to be more gentle to the soil. The forwarder with a weight of 11 metric tons and a load capacity of 15 metric tons is specified to have an average working speed of 7-10 km/h, a top speed in terrain of 15 km/h and a top speed on roads of 40 km/h.This master?s thesis aims at developing a conceptual design of the forwarder?s drive module which includes electric motor, gear unit, brake and drive wheel.To investigate if the requirements can be fulfilled a study of the dimensioning loading scenarios has been carried out. The resulting needs regarding the torque has been considered in order to determine the required gear ratios for different motor options.

Uptake of 137Cs by fungi and plants due to potassiumfertilization in Heby municipality in response to theChernobyl nuclear accident

The fallout from the Chernobyl nuclear accident resulted in large deposits of caesium, iodineand strontium as well as noble gases in various parts of Sweden. 137Cs has a radioactive halflifeof about 30 years and is therefore one of few radio-fission products remaining inmeasurable quantities in the Swedish soil. Radiocaesium behaves similarly to potassium insoil-plant systems and is easily absorbed by plants. It is important to understand how 137Csbehaves in different ecosystems in order to minimize the risk toward humans.The aim of this study was to determine how potassium fertilization influences radiocaesiumcontent in different forest plants and fungi. Potassium fertilizer was spread once in 1992 withapproximately 200 kg KCl per ha.

Vattenkvalitén i Fredstorpsbäcken - dikad bäck på fastigheten Rämningstorp i Skara kommun :

The estate of Rämningstorp in the region of Västergötland in southern Sweden is administered by the holding trust company Skogssällskapet i Skövde. In 1999 measures were taken by Skogssällskapet to drain the stream Fredstorpsbäcken as a means to increase the forest productivity of the surrounding lands, which are situated on the estate of Rämningstorp. Almost immediately after the drainage, the streamwater turned turbid and a landowner downstream reported the issue to the county administrative board of the region. The aim of this thesis was firstly to analyse the suspended matter that appeared during summer/autumn and secondly to explain why it came to be. Initial hypotheses for the explanation to the greyish turbid water were that it was either 1) a chemical/biochemical precipitate, or 2) an bacterial/algal blooming.

Träd och buskar i kantzoner : en undersökning av kanteffekter i några av östersjöregionens skogar

Around the world, forests are generally being fragmented and as plant populations decline in both sizeand number of individuals, the genetic variation will also decrease whitch in the end leads to totalextinction of the plant. In this paper, I wanted to investigate what specific species of trees and shrubsyou usually find in the edge and core habitats in some of the forests in the Baltic Sea region. I alsowanted to identify the edge effects and their sources and finally compare the results between thedifferent regions.The data sources used are derived from the ongoining research project Landscape structures, patterns ofbiodiversity and conservation strategies in the Baltic Sea region by Kari Lehtilä, Patrik Dinnétz ochTiina Vinter who have made a record of all herbaceous plant species in four randomly chosen forestregions situated around the Baltic Sea: Estonia, Skåne, Södermanland and Germany. I made statisticalanalyses, using the computer program R, concerning the distribution of species in the edge habitats ofthe forests as well as in the core habitats. I performed generalized linear models and then variationanalyses with the factors light and biomass in order to investigate wether edge effects might appear dueto these factors.

Årstidsdynamik för kvicksilver i ett sövattensediment :

The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment. The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake. Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.

Interactions between some plant-parasitic nematodes and Rhizoctonia solani in potato fields

The pathogenic fungus Rhizoctonia solani causes major economic losses for potato producers in Sweden. The producers, as well as advisors, have reported possible increases in severity of R. solani when free-living plant parasitic nematodes are present and active. There are several examples in the literature of interactions between pathogens where one, or both species, support or increase the damage made by the other organism. These complexes are important to investigate and to be able to forecast, since even low incidences of fungi or nematodes may result in an interaction of significance.

Design Program for Dessie Campus, Wollo University, Ethiopia

A geographical position and its social, cultural and political context as well as climate and specific physical characteristics define the scope for a landscape design project. This has become clearer for us in our master project where we have made a Design Program for the outdoor environment of Wollo University in Dessie, Ethiopia and analysed and reflected on the work and process. The aim for the project has been to design an attractive and functional outdoor environment for the Campus, based on the inventories and the needs and wishes of clients and users. But, the aim has also been for us as landscape architect students to gain a greater knowledge about landscape architecture and the design process by position ourselves outside our usual context. The method has been open and seeking where the site, literature studies, dialogues with people and our own experiences from the field study in Ethiopia has influenced the work. Wollo University is situated 400 kilometers north of Addis Ababa, in a mountainous landscape. It faces problems of heavy rainfall during the summer, soil erosion, a lack of essential facilities, and is still a construction site with empty spaces in-between buildings and infrastructure.

Viltanpassad röjning längs skogsbilvägar som en foderskapande åtgärd för älgen

The moose is a keystone species in the boreal forest ecosystem, but the dense Swedish population do cause some serious problems. From a forestry perspective, their browsing on young Scot pine (Pinus sylvestris) causes extensive losses of revenue. Adjusting the cleaning along roadsides of low trafficked forest roads can favour the production of plant species preferred by the moose. This is thought to redirect the moose´s browsing to the roadsides and thereby decrease the damages on commercial forest.The aim of this study has been to present a first evaluation of the vegetation in roadsides, one year after wildlife-adapted roadside clearing has been undertaken. In the wildlifeadapted clearing operation, the roadside was widened by removal of some trees in the forest edge whereupon a complementary clearing with a conventional chain flail was conducted.

Smart seed : fördröjd groning hos raps : försök med frö-coating samt litteraturgenomgång om frögroning, coating och praktisk tillämpning i reläodling

Oilseed rape constitutes a good break crop within a cereal dominated cropping system. The normal sowing time for winter rape in Sweden is August. It's a time in the cropping year characterized by a heavy work load, such as harvest and soil management. In addition, it is often a period with large precipitation. Thus, it is sometimes problematic for the farmer to do the sowing of winter rape at the optimal time.

Volume and taper equations for Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst.) and White spruce (Picea glauca (Moench) Voss) in Iceland

The aim of this study was to evaluate different types of volume and taper equations that can be used to predict single-tree stem volume and stem diameter at any given height along the tree stem for plantation grown Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst) and White spruce (Picea glauca (Mounch) Voss) in Iceland. A number of published tree volume equations were tested and modified to predict the total stem volumes over bark but three logarithmic equations were taken for more in-depth analysis. Three taper equations were tested. Two variable-exponent equations (Kozak 1997, Kozak 2004) and one exponential equation described by Biging (1984). Data from a total of 617 sample trees were used in this study, collected from stands in various parts of the country and present different types of stands growing in different soil types and cover most of the site conditions suitable for forestry in Iceland.

In search for sustainable alternatives to lawns : connecting research and landscape design

A large part of Sweden?s green, urban landscape is covered by lawns. Approximately 80 000 ha of maintained grass lawns are part of public courtyards, schoolyards, parks, golf courses, sport fields and traffic environments. Beyond this figure, the lawn is also an essential element in most private villa-gardens. Lawns have become a universal phenomenon through the dispersion of landscape aesthetics from the Western world.

Daily rests of wild boar Sus scrofa sows in southern Sweden

For a few decades, the wild boars are established over large areas in southern and centralSweden. Where they cause problems in terms of damage to crops in the agriculturelandscape, where rooting, browsing and trampling, but also damage to the crop when wildboars chosen daily rest in the cultivated fields. Along with the growing number of wildboars the rate of car accident with wild boars has also increased.Here I examined the daily rests of wild boar (Sus scrofa) sows in southern Sweden, todetermine the factors which the wild boars sows choose for daily rest. By determining whatfactors are important in this selection of daily rests, we may be able to make managementmeasures to reduce the damage wild boars make in the agriculture landscape by attractingthem to places where they do less economic damage and accidents on roads.In this study I have examined 123 daily rest positions from 14 different individual wildboar sows fitted with GPS collared in Southern Sweden, Skåne County in Christinehof,Högestad Kronovalls estate. Data was collared over the years 2004-2006 during the periodfrom June 1 to September 30.

En analys av SCA Skog AB's metod för egenuppföljning av gallringar :

A high quality is highly requested in today?s thinnings, since these are the base for continued value development of the forests. Thinning quality often means a minimization of damages on soil, stems and roots during the cutting. One way to reach a high quality is to set up goals that will be followed up after the cutting is made. Self-checking gives information of the machine drivers work and guarantees the customers a good quality of work.

Småskalig livsmedelsförsörjning av mjölk :

During the last year?s Swedish agriculture have had difficult times, with decreasing prices and at the same time increasing production costs, which has led to bad profitability and faith in the future. The dairies in Sweden have also had a rough time and there have been large rationalizations during the years. In the beginning of the 20th century there were almost 1700 diaries in the Swedish countryside. There has been a large technical development during the 20th century resulting in a decrease in diaries to only 46 in the whole country today. They are owned by 15 diary companies, of which 7 large and dominate on the market and the rest are small-scale companies. With this development the confidence and feeling for the diary companies also has decreased.

Gimo bruksområde - inventering och riskklassning enligt MIFO fas 1 :

This master thesis encompasses an inventory of the older industrial community of Gimo. Investigations of the contamination situation for each industrial area were done. A risk classification according to the Swedish Environmental Protection Agency?s ?Method of Surveying Contaminated Sites?, phase one, followed. The risk classification was done on areas of Iron Work, a rockwool industry and a landfill. Gimo have had iron manufacturing from 1615 until 1945. Gimo have had two blast-furnaces and two smithies periodically.

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