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535 Uppsatser om Soil contamination - Sida 20 av 36

Undersökning av sambandet mellan strålningstemperatur och NDVI i Sahel

Several studies have analysed the relationship between Normalised DifferenceVegetation Index (NDVI) and radiative surface temperature. A main goal for moststudies have been to find the best method for carrying out land cover classificationsand to study land cover changes, based on a combination between the twoparameters. Since atmospheric components have a significant influence on bothparameters, most applications were based on multi-temporal data. The quality of theindividual values in such a combination is improved, but the biophysical justificationis uncertain. This study presents a different method, based on only the combination ofvalues that have been registered the same day and about the same time of the day.125 daily images of NDVI and 250 images of radiometric temperature were used inorder to analyse the relationship between (1) NDVI and radiative temperature and (2)NDVI and relative temperature difference between early morning and mid-day.Results between NDVI and radiative temperature show a significant negativecorrelation on areas where a distinct growing season develops, and a strong positivcorrelation where vegetation is abscent throghout the season.

Förskolebarns motoriska utveckling : -Hur en förskolegård bör utformas för bästa tänkbara utveckling av barns motorik

The purpose of this study was to interview different groups of people (preschool teatcher, parents and theire childen) involved in preschool about their view on outdoor activity and children´s motoric development, and how a preschool yard should be designed to promote childrens development.All parties regard outdoor activity as very important for the development of children. They also think that the outdoor environment today is good but that it could be improved by including some trees and hills. The yard should also contain soil, sand, clay and water. The children prefer grass on the ground over other substrates. This study also gives good indications to decision makers how to build new or to reconstruct pre-school yards in the future..

Betula : arter och sorter

As birch is one of the most common trees in Sweden, and probably one of the easiest for someone who lives here to identify, it is interesting to note that most people do not know how variable the genus is and how widely it is distributed across the northern hemisphere. One can find birch growing at both high and low elevations, demanding different soil conditions and preferring varying amounts of sunlight. Many people may also be surprised to hear that the colour of the bark can vary from bight white to almost black, and different shades of pink, orange and red can also be displayed. This, together with the astonishing beauty of the genus, the important role as a pioneer in many ecological systems and the difficulty in sorting out the taxonomy of the genus, constitutes the background of this thesis. The thesis is written at the Department of Landscape Development in Alnarp, Sweden with Kenneth Lorentzon, researcher at the Swedish University of Agriculture as a supervisor. The aim of this thesis is to highlight which species and cultivars within the genus Betula could be appropriate for horticultural use in Sweden.

Evaluation of an ectomycorrhizal macrofungi as an indicator species of high conservation value pine-heath forests in northern Sweden

Since the 1950s, the development of modern rotation forestry in boreal Fennoscandia has resulted in a severe reduction of older forests, and a high degree of fragmentation among the small patches that remains of old forest. In Sweden, when performing conservation value assessments in order to identify and preserve the remaining forest habitats, the government authorities use to a significant extent a set of indicator species that indicate habitats of high biological conservation value. One species considered to indicate high conservation values in pine-heath forests is the red-listed ectomycorrhizal (EM) macrofungi Sarcodon scabrosus (Fr.) P. Karst. In the present study, the validity of using S.

Är bor nödvändigt vid skogsgödsling i Sverige?

This thesis has been made on behalf of SCA Skog AB to assess the need of boron in Swedishforest fertilization. Boron has been added to Swedish forest fertilizers since the beginning of the1980s. This makes the fertilizers more expensive and therefore has the necessity of boron inSwedish forest fertilization been raised.The Swedish bedrock generally contains small amounts of boron. The boron in the bedrock istightly bound to the mineral tourmaline and mostly unavailable for plants. This leads to that thecontribution of boron to the soil from weathering is very low besides soils with marinesediments.

Kväveläckage inom Tolångaåns dräneringsområde : modellering och åtgärdssimulering

Under de senaste 300 åren har jordbrukslandskapet i Sverige genomgått stora förändringar. I början av 1900-talet introducerades konstgödslet och efter andra världskriget ökade gödslingen dramatiskt i syfte att maximera produktionen. Detta har lett till att överskottet av kväve har spolats ut i vattendragen. I detta arbete har stor vikt lagts vid att skapa en egen kvävemodell i syfte att simulera kväveläckaget från jordbruksmarken i Tolångaåns dräneringsområde..

Bakterietillväxt i strömedel till mjölkkor

The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores. In this literature study the most commonly used bedding materials; straw, sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied. Most bacteria need humidity and prefer a quite high water activity to be able to grow.

Spårelement i Sveriges jordbruksmark : flöden, trender och fältbalanser

Field balances based on supply and removal of trace elements from the topsoil have been calculatedfor farms specialized in crop, dairy and pig production in Sweden. Today's field balances have beencompared with the field balances of 1990 in order to examine if, and then how, the situation haschanged. Studied trace elements are arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu),mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn).The balance calculations show that the stores of Cu and Zn are depleted with an average rate of -15% and -6 % over a 100-years period on crop farms when only commercial fertilizers are being used.The concentrations of Hg and Pb tend to increase in the topsoil on crop farms with more than 3 % forHg and with 2 % for Pb in 100 years. There is today balance between supply and removal of the traceelements As, Cd, Cr, Mn and Ni. In the south of Sweden, on crop farms with sugar beets in the croprotation, one can see a decrease in the concentration of Cd in the top soil by -6 % over a period of100 years.

Skogsentreprenör 2007 : en kvantitativ studie av organiserade skogsentreprenörer i Sverige

SMF Skogsentreprenörerna is a nationwide organisation for Swedish forestry contractors. It has about 750 organised companies with somewhere around 1500 logging machines. These machines perform well over 50% of all yearly landed wood in Sweden. The members of SMF also performs more and more of other functions in Swedish professional forestry, such as soil scarification, planting and pre-commercial thinning of younger stands. In order to determine what major priorities SMF should focus on in the future a member survey was initialised and carried out by SMF together with Daniel Larsson-Snygg, student at the swedish university of agricultural sciences SLU. This report presents the result of this survey sent out to all members of SMF. It is intended to answer a number of questions about their entrepreneurship such as: What different kinds of work do these companies perform? How many machines and employees do they have? How old are the company owners and their employees? What are their thoughts about the future of their business? How well does SMF serve their members needs?.

Naturlig föryngring av lövskogar i Örebro län :

The Regional Forestry Board in Värmland- Örebro needs increased knowledge on silviculture in broad- leaved forests. This thesis is an inventory of naturally regenerated broad leaved forests, and the results from the inventory have been compared with The Regional Forestry Board?s demands on regeneration results. The result of this inventory was that the regenerated sites were suitable for broad leaved trees, but only half the number of the stands fulfilled the demands of regeneration results of The Regional Forestry Board, mainly because of gaps in the stands. The gaps in the stands were mainly caused by lack of soil preparation and seed trees..

Stadsodling : möjligheter och begränsningar

Urban farming can be viewed in several contexts. The first part of this work brings up the beneficial effects of farming on our physical and mental health, knowledge as well as on social life in cities. The introduction of gardening in schools can contribute to an increased awareness on both agricultural practices and importance as well as ecological processes. It can also be used in teaching of other subjects. Farming can also contribute to improving the household economy, and the economy on a municipal or national level.

Utformning & placering av vädringskanaler i ett passivhus, drivet av naturliga krafter

A passive house in Norra Djurgårdsstaden drawn by Tengbom Arkitekter is going to be built. A shaft for airing is needed for a few apartments in the house.The airing shaft is designed for a few two room apartments in the house, which are not able to achieve satisfactory airing, as their outer walls are facing a single direction. The other apartments on the same floor are corner apartments. These apartments do not have the same difficulty with airing since they have their outer walls in different directions, with different pressures at the facades. The airflow in the airing shaft is supposed to be driven only by natural forces, by the sun. The purpose of natural driven forces is to achieve low energy consumption for the house.In this thesis, a design of the shaft for airing has been developed.Initially an open shaft for all apartments was analyzed.

Höjning av vattennivån i Mälaren : Ett hot mot Stockholms centrala delar vid en framtida klimatförändring?

In today?s World is climate change an important and hot topic. Climate scenarios for Sweden show a warmer climate, especially during the autumn, winter and spring. The same climate scenarios also show that the precipitation will increase during this part of the year, however, during the summer the opposite is expected to occur. The purpose of this essay is to examine how future climate change will affect Stockholm especially the expected increase in precipitation, which may lead to a rising level of the Lake Mälaren. During 2000/2001 was Stockholm hit by a flood. This flood nearly resulted in major consequences and showed that there were significant risks for the city of Stockholm and increasing precipitation will result in even more water in the drainage systems of Lake Mälaren. The results presented here show that it is important to increase the drainage capacity of Lake Mälaren in order to reduce the risks of flooding in the central parts of Stockholm.

Förslag till modell av kemikaliespridning i mark anpassad för användning vid räddningsinsats - Kemspill Mark 4.0

After emergencies involving chemical spills it is of great importance that correct measures are taken with short notice, both for the security of people and in order to minimize future environmental consequences. The RIB-unit at the Swedish Rescue Services Agency initiated this study, the aim of which is to propose changes to the existing chemical transport calculation tool: Chemical Spill 3.4, included in RIB - Integrated Decision Support for Civil Protection, so that it can be used for decision support as well as in preventive work. A rough estimation of chemical transport in the subsurface is considered being of great importance when making decisions during emergency response operations.The proposition presented in this report is a non site specific chemical transport model which is designed to give a rough estimation of NAPL flow in homogenous isotropic soil shortly after an instantaneous release. The model can be used at two levels; both in situations without access to information on subsurface properties, and with more accuracy in situations with knowledge of the included parameters. For that reason the user can choose among predefined alternatives or assign the parameters a numeric value to increase the quality of the model output.

Att Synliggöra det Osynliga : GIS som verktyg i sökandet  efter bosättningsområden från bronsåldern på Gotland

In this bachelor essay an attempt is done, to recreate a probable Bronze Age landscape on Gotland, with GIS as a tool. The landscape on Gotland is situated with many different monuments dated Bronze Age, such as cairns and stone ships. In creating of the maps, two possible shorelines contemporary with the Bronze Age have been calculated and marked on the maps. Furthermore, peat lands have been drawn upon the maps, by using the information from geological maps.A landscape variable have been compared between Bronze Age places and Early Iron Age houses; the soil type. On Bronze Age places gravel is the most common, while moraine marl is the most common on places with Early Iron Age houses.From a selection that were made, all Bronze Age places where within 3 km from the water, either the recreated shoreline or peat land.

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