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487 Uppsatser om Soil masses - Sida 30 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.

En jämförelse av sitkagranens (Picea sitchensis) och den vanliga granens (P. abies) produktion :

Sitka spruce (Picea sitchensis) is a tree species that have its natural distribution along the West Coast of North America, from Alaska in the north to northern California in the south. Sitka spruce is a typical coastal tree species that can reach heights up to 85 meters and occurs in single pure as well as in mixed stands. The main purposes of this study were to describe the Sitka spruce growing characteristics and the volume production in comparison to spruce (Picea abies). The possibility to predict future volume production by using prognosis tools designed to be used on spruce were also studied. The material that has been used in this study are permanent sitka trials established by the Faculty of Forestry fixed Sitka trials and also material gathered in this study. A literature study was also carried out in order to determine the Sitka spruce growing characteristics. Sitka spruce has a high adaptation and a high volume production on a broad scale of soil types. The tree species is a pioneer species that has a fast early growth and in combination with sharp needles it is less susceptible to animal browsing than spruce. The factor that is the single most limiting factor for where the Sitka spruce can be planted is frost. This factor can be limited by using plant material with a well-suited provenance. According to the literature, the Sitka spruce has an average total volume production that is between 20-40% higher than spruce.

Geosynteter för hållbara vägar : Modell för jämförelse av vägöverbyggnader med eller utan geotextiler och/eller geonät

The different material layers as part of a road construction fill all a function so theroad becomes durable, safe, comfortable and aesthetically pleasing. Recently, anew group of construction materials started to play an important role in roadconstruction ? geosynthetics.This thesis addresses the two most common types ofgeosynthetics used in modern road construction, namely geogrids and geotextiles.The most common use of geogrids is reinforcement of poor subgrade by usinggeogrid soil reinforcement, which occurs when road material particles wedge inthe geogrid?s mesh. Geotextiles act partly as a barrier that prevents the finermaterial in the below ground from being mixed with coarser upper material andalso act as a load spreader.Road contractors often face a choice of whether geogrids and/or geotextiles areappropriate in a particular road project and also how much profit the choice mightbring. This phase in the tender calculation process is the intended scope of thisthesis.The thesis deals with both the "hard" cost-function aspects and the "softer" values e.g.

Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon

Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient removal techniques. The aim of this study was to investigate the removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on removal efficiency was studied.

Skånes gröna guld : anläggning, odling & mossarter i mossträdgården

This is a 15 hp (10 p) thesis in biology at the programme for Horticulture Management at the Swedish University of Agricultural Sciences, Alnarp. In this literature study we have processed, reviewed and arranged facts and research, to make it more available for those who want to know more about establishment or cultivation of mosses. Our client is Fredriksdal?s Museums and Gardens in Helsingborg who are planning to establish a moss garden. The information is meant to be used by Fredriksdal and other similar facilities.

Karaktärisering av Gremmeniella-skadade bestånd inom Holmen Skog AB :

Since the end of the eighteenth century forest damage caused by the pathogen Gremmeniella abietina has been observed and documented. During the latest epidemic in Sweden more than 480 000 hectares forest land have been injured and this has lead to considerable economic losses. For the pathogen to succeed with infection, spore dispersal and colonization the right environmental conditions is required. The aim of this paper is to describe the diseased stands using site and stand characteristics and to evaluate the effect of these variables on the disease incidence. Further, the thinning performed during the time for spore dispersal and its relationship to injured stands is examined.

Monitoring and pest control of Fruit flies in Thailand : new knowledge for integrated pest management

Fruit flies (Tephritidae) are serious pests that cause enormous losses for farmers in many countries. The frequent use of insecticides in controlling fruit flies in fruits and vegetable has not resulted in sustainable management of the pest. Problems associated with this complete reliance on chemical control are many residues of insecticides in crops, health problems for farmers, contamination of water and soil, insecticide resistance development and decrease in natural enemy populations. The implementation of control measures that do not imply an added burden to the environment and/or the farmers is urgent. More knowledge about the ecology of fruit flies is the basis for finding new and better ways to control this pest.

Trädslagsinverkan på markvegetationens utveckling i odlingsförsök med tall och contorta :

In the 1970?s it was predicted that in the beginning of the 21st century there would be a timber shortage in Sweden and a large scale introduction of the exotic tree species lodgepole pine started. An introduction of a foreign tree species means a risk of a negative influence on the forests ecosystem. Today, the stands that were established in the 70?s are middle-aged and the effect on the forest floor vegetation can be studied.

Den positiva hälsovågen : En kvantitativ studie om hälsofrämjande arbete

The construction of buildings and paved surfaces changes the natural water balance.Precipitation generates surface runoff and storm water instead of infiltrating into the soil.Storm water has come to be considered as a major source of pollution in lakes and streams inthe vicinity of urban areas. Reduction of pollutants in storm water is a key action in order toprotect sensitive recipients and maintain high water quality. Storm water is traditionallytransported by storm sewers to the nearest recipient. In recent years the approach to stormwater management has changed; storm water should primarily be disposed of on site, throughlocal disposal of storm water, LOD. LOD is created by a combination of the function ofseveral smaller local facilities and the general sewer system.

Leaf area index in Vittelaria Paradoxa parklands in Burkina Faso estimated by light interception and leaf sampling

Burkina Faso as well as most sub-Saharan African countries struggle with providing food for a fast growing population. The dominating farming system is agroforestry parklands. Agroforestry parklands can broadly be defined as areas where scattered trees occur on farmlands as a result of selective clearing. The presence of trees in crop fields may in the long term have a positive effect on the production of annual crops. It is commonly discussed, but not proven, that the presence of trees leads to increased groundwater recharge due to higher infiltration capacity of the soil.

Metodik för resistenstest i renkavle : en studie om herbicidresistens; mekanismer, detektion och åtgärder

Herbicide resistance is the result of an evolutionary process where a population gradually changes from being susceptible to being resistant to an herbicide. The resistance mechanism is usually a change in the biochemistry of the weed, but in some cases changes in morphology or growth rhythm. The change is caused by random mutations. Two resistance mechanisms are found in black-grass; target site resistance and metabolic resistance.Black-grass is a tufty, winter annual grass weed, which is mainly found in milder climates. Black-grass is a big problem in Southern Europe.

Vilken effekt har lärkrutor på ogräsfloran vid ekologisk höstveteodling? :

This study forms part of the R&D project "Improved survival of bird chicks in organic fields" managed by the Rural Economy & Agricultural society in Uppsala. The skylark (Alauda arvensis) is a species that has decreased drastically in Sweden as a consequence of more intensive cropping. Studies in England have shown that skylark reproduction can be greatly improved within conventional fields, at a low cost, by establishing patches of bare ground (skylark plots). Within conventional farming, herbicides can be used in case a weed problem arises due to implementation of these skylark plots, whereas this is not allowed in organic farming. This study examined the effects of skylark plots on the weed culture in organic autumn-sown (winter) cereals and whether weeds might cause long-term problems to farmers. The study was conducted in two parts; a field study and a review of the literature regarding the weeds observed. The field study was carried out in 2007 during three weeks in June and three weeks in July, on eleven organic fields with winter cereal in the vicinity of Uppsala.

Sustainable shopping : consumer behavior in purchasing and donating secondhand clothes

Textiles are made in an unsustainable way and there is a need to find alternative ways and material to reduce the negative impacts on the environment, humans and animals. Problems like pollution, excessive water consumption and loss of soil fertility is a result of this lack of diversity. It is a necessity to find innovative alternatives in other fabrics due to the unsustainable use of cotton and polyester fibers. As in many other countries in the Western part of the world, in Sweden there is a rapid turnover and increased selling of clothes that result in increased textile waste. About 15 kilogram of textiles (net inflow) is consumed per person each year.

Grundvattenskydd och markanvändning i tre olika länder- effekter för miljö och samhälle

AbstractDrinking water is an important resource on Earth both for humans and animals. Although most of the surface is covered by water only a small quantity is available as drinking water. Our manner of living creates a lot of pollution which has an environmental impact. Groundwater has a protracted turnover time in the soil and it can take many years before the effects of human impact are detected. The Swedish environmental object is ?Good groundwater quality? which aims to provide a safe and sustainable supply of drinking water today and in the future.

Lokalt omhändertagande av dagvatten i Västerås - Möjligheter till ökad användning i befintliga innerstadsområden : Local disposal of storm water i Västerås - possibilities for increased use in downtown areas

The construction of buildings and paved surfaces changes the natural water balance.Precipitation generates surface runoff and storm water instead of infiltrating into the soil.Storm water has come to be considered as a major source of pollution in lakes and streams inthe vicinity of urban areas. Reduction of pollutants in storm water is a key action in order toprotect sensitive recipients and maintain high water quality. Storm water is traditionallytransported by storm sewers to the nearest recipient. In recent years the approach to stormwater management has changed; storm water should primarily be disposed of on site, throughlocal disposal of storm water, LOD. LOD is created by a combination of the function ofseveral smaller local facilities and the general sewer system.

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