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487 Uppsatser om Soil masses - Sida 24 av 33

Raä 977 - En lokal och tre aktivitetsytor. : En tvärvetenskaplig undersökning av Raä 977 vid Vojmsjön i Vilhelmina socken

This candidate thesis concerns the ?all but forgotten? material from the bronze age site named ?Raä 977, Hansbo 1:3, Vojmsjön, Vilhelmina?. During 1975-76, an archaeological dig was carried out by Västerbottens museum led by Ulla Walukiewich in an attempt to preserve the information the site held, before it was destroyed by the erosion brought on by the recently regulated sea ?Vojm? (Vojmsjön). The archaeological dig yielded a stunning amount of finds, samples and information previously unknown.

Realisering av en modulär skogsmaskin - En skalmodell

Wood for commercial use is harvested from forests using forest machines like harvesters which folds, branches and cuts trees and forwarders which transports logs to a landing area for further transport to a processing facility. Future forest machines have to be much gentler to the machine operators and forest soil than today's machines. Hence new machine solutions must be developed and tested. A practical way is to develop a physical scale model which can be used as a test-bed to incorporate different types of solutions for suspensions, cabin damping, tires and tracks, crane and overall architecture. The aim of this project was to develop such a 1:5 scale model of a forest machine, named as ?Skogbil.A scaling strategy was employed to arrive at important scale dimensions and specifications ofSkogbil which would be comparable to the full scale model.

Vattenkemin i Fyrisån under snösmältningen

Chemical substances are spread diffusely and uncontrollably as a result of the increased consumption of goods. REVAQ is a certification system that works to reduce the flow of hazardous substances to Swedish treatment plants and to create a sustainable nutrient recycling. According to REVAQ, the yearly accumulating rate of metals should not exceed 0.2% in soil per year. Silver and bismuth are two metals that do not fulfill this requirement. The silver concentration in sludge decreased during the last decade, however the last few years, it has leveled off.

Årlig gödsling med NPK bäst för gröda, miljö och ekonomi

Yesterdays common fertilizing strategy was to apply phosphor (P) and potassium (K) in thefall a few times in the crop rotation. In the spring only nitrogen (N) was applied. Recent trialsand studies has shown that this strategy, N+P/PK, is ineffective compared with the systemwhere NPK is spread every year in the spring. The strategy with annual NPK-fertilizer in thespring has proven to be better for the crop, the environment and the farmers economy.In the NPK-system the crop responds with higher yields and better quality, especially in thespring cereals. This is mainly because of an interaction between the different nutrients in thefertilizer.

Risk för exponering av växtskyddsmedel i växthusmiljö

Plant Protection Products (PPP) used in the horticulture industry can be both chemical and biological. They are used for weeds (herbicides), insects (insecticides), and fungi (fungicides) and as growth retarders.Many horticulture workers get in touch with plants, treated with PPPs and many of these don?t use any protective equipment.The aim of this project is to illustrate the work environment hazards for staff working with greenhouse pot plants, after they have been sprayed.The method used was observations of the operations for packing plants. I studied the operations and took notes of how operations were performed and what protective equipment they used. I also took photos and asked questions.A literature study completed the observations.

Allt utom byn Sökandet efter en vikingatida by i sydöstra Blekinge, med områdena runt Järrestad på Österlen och Sorte Muld på Bornholm som jämförelsematerial.

The purpose of this essay is to see if villages or bigger settlement locations can be found in south-eastern Blekinge during the viking age. There have been many archaeological findings from this period in Blekinge, for example grave findings, ring-forts , old roads and ancient harbors. But no evidence of a village has been found yet. If south-eastern Blekinge is compared with the area surrounding Järrestad on Österlen in south-eastern Skåne and the area surrounding Sorte Muld on Bornholm, many likenesses can be seen. In this essay, the findings in Blekinge will be used as different components when the three areas are compared with each other.

Vinterförvaring av Pelargonium x hortorum :

There are many different recommendations on how to keep pelargoniums over winter, but most of the recommendations suggest ?the higher the temperature, the more light and water the pelargonium needs?. The purpose with this paper is to try to explain the best and the worst results that are achieved with different storage alternatives of zonal pelargoniums. The results are based on an orientating investigation carried out in January-February, and a questionnaire that members of the Swedish Pelargonium Society answered to. Both the orientating investigation and the questionnaire showed that zonal pelargoniums are best stored light and cold but frost free. They should be irrigated according to their needs which is when the soil is dry, about every second to third week. Zonal pelargoniums are very resistant to drought and can survive without water for at least 44 days, both when kept under light and cold as well as under light and warm.

Föryngringsresultat och beräknad virkesproduktion i naturligt föryngrade tallbestånd i Västerbotten under mitten av 1990-talet :

According to the Board of Forestry, in Västerbotten, many natural regenerations of Scots pine (Pinus sylvestris) carried out on privately owned forest in the middle of 1990 in Västerbotten have rendered a bad regeneration outcome and will provide a low future forest production. The Board of Forestry believes that the negative result can be explained by the fact that the regeneration has been carried out in wrong locations and that scarification failed to work as planned. In order for an accepted rate of regeneration the guidelines of the Forrest Act require, not less than 10 years after final cutting at natural regeneration, that there should be at least 1300 (site indices 16 m) - 1700 (site indices 20 m) main crop stems per hectare. Main crop stems are defined as stems according to the place of growth and appropriate tree type, in addition with regard to quality, stage of development and damage risk have a prospect of succeeding. In addition main crop stems should be separated by surface so that the proportion sample plots with 3 meters radius, and lack main crop stems, are not more than 10 % of site indices 14 meters or higher.

Störningsregimer vid Skövde övnings- och skjutfält : Stridsfordons påverkan på olika naturtyper i militära övningsområden

A lot of habitats have declined or disappeared as the old cultural landscape changed to the modern agricultural landscape of today. Places such as power line corridors, racing tracks, gravel pits and military training sites have become refuges for many species associated with the old cultural landscape. These sites have been exposed to ecological disturbances that create the same type of habitats that were found in the old cultural landscape.The military training sites in Sweden has an impressive diversity of species. Disturbances from the military exercises have created habitats that are important for a wide range of species.The purpose of this thesis is to study some of the ecological disturbances occurring in the military training sites of the Swedish Armed Forces and examine how they affect different types of habitats. The thesis explains through litterateur and field studies the reason to the rich biodiversity often found at military training sites.

Ammoniakförluster vid flytgödselhantering : myllning och surgörning som metoder för att minska avgång vid spridning

The ammonia emissions are an environmental issue since they contribute to eutrophication. By far the largest source of ammonia emissions is manure from agriculture and should therefore be reduced. Loss of ammonia is not only negative for the environment but also to the farmer who loses nitrogen that could have been used by the crop. The focus of this study has been emissions from spreading slurry where the loss can vary widely depending on slurry-, soil-, and weather conditions. There are mainly two different ways to reduce the emissions. One is to inject or mix the slurry into the ground to avoid air contact. The other way is to use acid to reduce the pH in the slurry to a level between 5 and 6 where the equilibrium is so strongly pushed to NH4+ that hardly any NH3 can be lost.

Finns det potential att införa en massdatabas för handel och utbyte av överskottsmassor i Eskilstuna?

In Eskilstuna and Sweden in general the level of reuse of surplus material containing soils and rocks from excavation is low. In this report the potential for increasing the reuse of excavated material in Eskilstuna by using a web-based earth information database has been examined. The purpose of a web-based earth information database is to connect those who have surplus material with those who need material for a fast and simple transaction. The intention is to give Eskilstuna a more environmentally and economically efficient handling of surplus material by increasing the level of reuse and thereby reducing the amount of surplus material that is wasted and emissions given off to the atmosphere during transportation. The potential has been examined in two different ways, by tracing information about a number of projects to see if excavated material driven to the dump could have been used in another project and by interviewing eight of the work leaders active in Eskilstuna.

Mark röjd från sten : En studie av förklaringar och tolkningar kring röjningsröseområden

AbstractThis essay discusses different explanations and interpretations of what characterizes large areas containing clearance cairns (cairn fields). Results from the analyses show that there are different explanations about when and why cairn fields and clearance cairns occur. Explanations vary from introduction of the wooden ard in the early Bronze Age to the introduction of rational hay-making in the Roman Iron Age.  There is, anyway, relative agreement considering why and when cairn fields were abandoned. The reason suggested is an increasing pasturage with the consequence of reducing soil to poverty during the period of the Great Migration or in the Viking Age.The most likely cultivation system in cairn fields is a system consisting of both intensive and extensive characteristics. The latter coincides with the probable mobility of settlements.

Examination of mycorrhizal associations of Allanblackia stuhlmannii : a tree under current domestication

Allanblackia is a tree genus native to humid forests in West, Central and East Africa. Its fruits contain large seeds from which edible high-quality fat can be extracted. In order to create a sustainable supply chain of Allanblackia seeds, a domestication program has been initiated with the purpose to enable smallholder farmers to grow the tree as an agroforestry component and cash crop. More knowledge is required to understand the tree?s biology and possible symbioses involving soil microorganisms with plant growth enhancing poten-tial.

Klibbalens gödslingseffekt på volymproduktionen i ett blandbestånd av gran och klibbal : en simulering i Heureka

A secondary and a pioneer tree species can with advantage be included in a mixed stand to increase the use of sunlight. Nitrogen-fixing plants have been shown to increase the supply of nitrogen in the soil by, for example, litter fall. This deposition acts as a biological fertilization, which may be used by non-fixing plants. Alder is a nitrogen-fixing, pioneer tree species that loses its nitrogen-rich leaves late in the autumn. The aim of this study was to examine the effect on the total volume of production, when different proportions of nitrogen-fixing Alder were part of spruce stands.

Skogsentreprenad idag och i framtiden : en kvalitativ studie av skogsmaskinentreprenörersverksamhet och framtidsvisioner

The Department of Forest Products and Management, Swedish University of Agricultural Sciences has received means from Vinnova for a preliminary study of the organisation of logging work of today and how a better logging organisation should be brought about. This thesis reports results from qualitative interviews with nine forest machine contractors regarding the situation of their companies. The interviews have been analysed with respect to the genesis of the companies, which tasks they perform or that they could consider perform-ing, business relationships of the companies, relationships between the different partners of the companies, and the state of competition experienced by the contractors. The companies have developed either from the contractor previously being machine operator employee or from that the contractor in making has owned a machine and needed work. Their primary business is mechanised logging.

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