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490 Uppsatser om Excavated soil - Sida 1 av 33

Förutsättningar och hinder för att använda offentlig upphandling som styrmedel för en hållbar hantering av entreprenadberg

Large volumes of Excavated soil and rock are generated in building- and construction projects. These materials need to be transported longer and longer distances due to the densifications of cities. The transportation affects the environment in terms of noise and emissions, but also makes high demands on road infrastructure. To reduce the transport distances an increased responsibility for the excavated rock generated needs to be taken. Responsibility can be increased through an introduction of means of control.

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.

Kvävemineralisering från stallgödsel beroende på olika grad av inblandning i mark

The impact of the distribution in the soil volume of two farm manures on the net mineralization and immobilization processes of nitrogen were studied in an incubation experiment. Cattle slurry and broiler litter were placed in the soil with three procedures for incorporation including placement on top of the soil (TOP), in the middle of the soil (MID) and mixed homogenously with the soil (MIX). During the two weeks of incubation, few significant differences in net mineralization were seen between TOP, MID and MIX. However, there was a tendency that MIX led to a larger net immobilization of N than placement at one point (TOP and MID). This is also the result in the literature.

Markskadefri avverkning - från traktplanering till plantering

This study is made for Södra skog and is concerning how to minimize soil damage from planning to plantation. The purpose of the study is from the respondent?s perspectives; their own ideas and approaches. What emerged from the interviews is that the communication between the different organization levels can be improved. It is also important to prevent damage on the soil and to have in mind that the process of planning tracks to plantation continues for a long time and because of that, the soil condition meanwhile will change..

Långsiktig förändring av fosforhalt och skördenivåer för jordar med höga P-AL-tal : en analys av försöksserien "Exploatering av höga fosfortillstånd"

The field trial Exploatering av höga P-AL-tal (Exploiting P in heavily P dressed soils) started in 1982-1983 and included seventeen study sites placed across Sweden. Each site included three treatments, one unfertilized control (A), one aiming at replenishment of harvest removal, i.e. fertilized with 15 kg P ha-1 year-1 (B) and one over-fertilized (C) with 30 kg P ha-1 year-1. In this thesis data from the five longestrunning study sites are analysed based on four hypotheses. The hypotheses stated that in soils with high P-AL values and a pH over 6.0 P-AL will not decrease over time in the control (A) or in the replenishment treatment (B), that P-AL and P-HCl in the top soil will increase at all sites for the over-fertilized treatment (C) and that yields will not decrease as long as the P-AL is above 12 mg P 100 g-1 soil. My conclusions from the analysis of data from the selected sites are as follows: - A pH above 6.0 cannot guarantee a stable P-AL value in an unfertilized but phosphorus-rich soil. - The P-AL of unfertilized soils decreased faster at lower soil pH than at higher pH. - In the replenishment treatment (B) the rate of P-AL decrease seems to fall at a pH of 6.5. However, the influence of the soil type cannot be ignored. - P-AL and P-HCl did not increase in all over-fertilized treatments.

Vinster med björkinblandning i granbestånd i syfte att höja markens pH-värde

The soil acidification and the pH-value of the soil have been discussed for many years. Many observations of the tree species effects on the soil pH have been done. We have discussed the effects on the soil surface pH-value with a birch (Betula spp. L.) admixture in Norway spruce stands (Picea abies L.).We have used data from the Swedish National Forest Inventory. We have also discussed how the wood production and the biodiversity can be increased in mixed stands, in according to the Swedish forestry act Skogsvårdslagen. Our sampling areas are located in Norrland, Sweden. The results show a significant correlation between an increased birch admixture and an increased pH-value of the soil.

Megalitgravarna i öst : Megalitgravar i förhållande till bopats och landskap på Öland

The aim of this essay is to see if there are any relationship between the four Megalithic graves, and the newly excavated dwelling site in Resmo socken on Öland. The Megalithic graves on Öland consist of one dolmen and three passage graves. Is the excavated site a settlement? Since there are no signs of housing constructions, I will also explore other possible purposes of the site. What surprised the excavators was the concentration of pits that contained ceramics, flints and burned bones.

Med passare och snöre : att planlägga ett hus under järnåldern

This essay concerns the interpretation of house plans in three-aisled longhouses and hall-buildings, in Scandinavia during Iron Age. Full scale house reconstructions need a better basis of interpretations to understand the patterns of roof supporting post holes in excavated house plans. This has led to the thesis, presented here, that the layout of house plans during Iron Age is based on geometrical proportions. In order to prove this, geometric house plans were applied and compared with excavated house plans in 11different case studies, including the fortification of Fyrkat Denmark. It was found that all house plans in the case studies indicate, that the geometrical proportions 1:2, 1:3 and 2:3 of a given circle must have been used for the basic layout of the roof supporting post holes, using a compass and a straightedge.

Återanvända Fornlämningar : En studie av Ölands Rösen

AbstractErlandsson, K-O. 2007. Återanvända fornlämningar. En studie av Ölands rösen. Re-used ancient monuments.

Strukturkalkningens möjlighet att hindra fosforutlakning : en litteraturstudie

The purpose of this essay is to find out if liming with Ca(OH2) and CaO can reduce leachingof phosphorus from agricultural land and the problem with eutrophication. This purpose alsoincludes getting knowledge about how to make the phosphorus retained in the soil and beaccessible for the plants. This essay is supposed to show if more research is needed in thissubject. There has not been much research about this subject and therefore the amount ofmaterial to study is limited in this literature review. The research reports that have beenstudied have similar results.

Olika metoder och tekniska hjälpmedel för att bestämma bevattningstidpunkt :

This examination work on studies and research in articles is mostly from other countries. The purpose of the examination work have been to find out if there are any means you can work with to find out when its time to start irrigation, how they works and if they are credible. In Sweden there is not many means for decide when it?s time to irrigate and how much water you should appear. Swedish farmers think they have so much experience that they don?t need techniques like this.

Soil carbon, pH and yield development in a long-term humus balance trial

Agriculture has to be performed in a sustainable way in order to sustain high yields and to support a globally growing population. Functional soil properties are fundamental for high yields and in order to achieve good soil conditions sustainable management is a key. Loss of soil organic material and increased soil acidity are problems associated with degradation of soils and hence less sustainable agriculture. In this thesis, the effect of different agricultural systems on soil organic matter, pH and yield was examined. The systems examined are a cereal system with straw removal or returning and a ley system, all with different nitrogen levels.

Hur en ökad marktemperatur påverkar fotosyntes och markrespiration i en boreal skog

During the year of 2008, a powerful earthquake hit the southern part of Iceland, which changed the geothermal conditions in the area around the city of Hveragerdi. Elevated soil temperatures in a nearby forest plantation have contributed to a unique opportunity for researchers to study how an increased soil temperature affects the boreal forest ecosystem, something that partly can be connected to the climate changes which are happening today. The boreal forest is representing a carbon sink and a buffert for the emissions that occurs. Changes in this ecosystem will for that reason contribute to major impact for the global carbon cycle. To study the impact of how elevated soil temperatures affects different processes in a plantation of Sitka spruce, studies were made on the photosynthesis of the trees and the respiration from the soil.

Bok- och grankonkurrens i Sydsverige - markegenskaper och naturlig föryngring :

In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.

Metodutveckling för analys av klorfenoler i jord samt analys av förorenad jord från ett sågverk

In this final thesis, an existing method for analysis of chlorophenols (CP) in bottom sediments has been updated and adjusted for analysis of chlorophenols in soil. The covalent bonds between the chlorophenols and the soil matrix were broken through basic hydrolysis and the chlorophenols were then separated from the water phase through addition of sulphuric acid followed by ether extraction. The chromatography was improved through extractive acetylation of the chlorophenols.The updated method was then applied on soil samples from a contaminated area (a former sawmill in Hyttsjö, Östergötland, Sweden).The analyse was preformed by GC/MS with respect to 2-MonoCP, 4-MonoCP, 2,4-DiCP, 2,6-DiCP, 2,4,6-TriCP, 2,3,4,6-TetraCP and pentachlorophenol (PCP).Contamination of chlorophenols in nature can be explained by the former use of wood preservative chemicals based on chlorophenols. In the 1960s and the 1970s these chemicals were used in Sweden, but due to their toxicity they were banned by the Swedish government in 1978.In Hyttsjö a pentachlorophenol-based product named Santobrite was used for several years. The concentration of PCP in the soil samples from Hyttsjö varied from 0.2->1.8 ng/mg dry substance.

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