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523 Uppsatser om Contaminated soil - Sida 29 av 35

Contortatallens odlingsvärde i Götaland

The third most common conifer in Sweden is Pinus contorta (lodgepole pine). It originates from the western part of North America and was brought here in the end of the 1920s. The lodgepole pine is today allowed for commercial plantations in central and northern Sweden, excluding high altitude locations. Since 1979 only plantations with scientific purpose are allowed in south-central and south Sweden. This document is focused on how lodgepole pine manage perform compared with Pinus sylvestris (Scots pine) in the southernmost part of Sweden, Götaland. The idea came from the fact that the Swedish government is evaluating a notification from the National Forest Agency that suggests lodgepole pine to be allowed for commercial plantation even in southern Sweden.

Kläder i hampa - ett miljövänligt alternativ/komplement till bomull?

Hemp has been used for textiles for a long time in history until it became illegal to grow in many countries in the 1930s. It is interesting from an environmental point of view because it doesn?t need any pesticides and in most locations it doesn?t need any irrigation either, compared to cotton, which normally requires big amounts of both pesticides and water for irrigation. Hemp is a bast fiber, which means that the fibers are located on the bast of the stem (on the outer layer of the stem). Therefore they cannot be spun directly, they have to be removed from the stem first.

Utvärdering av osäkerhet och variabilitet vid beräkning av riktvärden för förorenad mark

I Sverige finns cirka 80 000 identifierade förorenade områden som i vissa fall behöver efterbehandling för att hantera föroreningssituationen. Naturvårdsverket publicerade 2009 ett reviderat vägledningsmaterial för riskbedömningar av förorenade områden tillsammans med en beräkningsmodell för att ta fram riktvärden. Riktvärdesmodellen är deterministisk och genererar enskilda riktvärden för ämnen under givna förutsättningar. Modellen tar inte explicit hänsyn till osäkerhet och variabilitet utan hanterar istället det implicit med säkerhets­faktorer och genom att användaren alltid utgår från ett rimligt värsta scenario vid val av parametervärden.En metod för att hantera osäkerhet och variabilitet i riskbedömningar är att göra en så kallad probabilistisk riskbedömning med Monte Carlo-simuleringar. Fördelen med detta är att ingångsparametrar kan definieras med sannolikhetsfördelningar och på så vis hantera inverkan av osäkerhet och variabilitet.

H?RNERVMOSSA I SANDSJ?BACKA NATURRESERVAT: Analys av h?rnervmossans invasivitet p? ljunghedens vegetationstyper

Heath star moss (Campylopus introflexus) is an alien species in Sweden and is currently classified as composing a "very high risk? of becoming invasive in the country according to SLU, and has in several parts of the world taken over large areas in a short time. The moss is characterized by its preference for disturbed and burned land, something that occurs on the heathland in the Sandsj?backa nature reserve, when burning for nature conservation purposes is carried out annually. Sandsj?backa's heathland is a valuable ecosystem and is one of the few heathlands in a favorable condition that remains in Sweden after strong reforms in modern agriculture in the last century, which led to forest succession of these cultural environments.

Etableringsstrategier för spannmål : en studie av investeringsbeslut i maskinsystem

In order to produce grain in an economically rational manner numerous decisions have to be made. One of these decisions is what tillage system to use. The cost of the tillage system is a large part of the total cost in grain production. Different tillage systems result in different distribution of fixed costs, operating costs and timeliness costs. The price of the produced grain and cost of inputs also affect the best way to produce grain.

Retrospektiv studie av porcint circovirus typ 2 och postweaning multisystemic wasting syndrome i Sverige :

Porcine circovirus type 2 (PCV2) is a common virus present in most parts of the world. PCV2 has been pointed out as the major causative agent to post weaning multisystemic wasting syndrome (PMWS) that affects pigs after weaning. The clinical symptoms of PMWS are impaired growth, diarrhoea, respiratory problems and increased mortality. At autopsy enlarged lymph nodes with depletion of lymphocytes are commonly found. Since 1991 PMWS has spread all over the world and was first described among Swedish pigs in 2003. Although PCV2 is widespread, only some pigs develop PCV2-related diseases. Why this is and what other factors that are required in order for the disease to develop is yet unknown. The main theories involve other infections, for example PRRS, and management issues but also genetic differences between pigs and/or virus strains have been suggested.

Rotinträngning i VA-ledningar : en fallstudie i Växjö

Mitt syfte var att, genom min uppsats få en ökad förståelse för de faktorer som påverkar när och hur en rotinträngning uppstår, och genom denna förståelse försöka utarbeta rekommendationer för att både minska risken för rotinträngningar och hitta lämpliga lösningar på befintliga rotproblem. Uppsatsen består av två delar, en litteraturstudie och en fallstudie. Litteraturstudien bygger på relevant litteratur som ska ge en bild av problemen med träd i städer och tidigare gjord forskning inom ämnet. Fallstudien är gjord på fyra olika områden i Växjö som har problem med rotinträngningar i VA-ledningar. Där det har gått har jag jämfört tidigare filmningar med filmning som gjorts nu i höst för att få en uppfattning av hur stort problemet med rotinträngningar är i de valda områdena. De fyra områdena i min fallstudie har alla olika rotinträngningsproblem, och därigenom olika rekommenderade åtgärder. Alpgatan består av privatägda träd med endast ett fåtal större rotinträngningar.

Påskön. Myten om Rapa Nui

This essay will examine the historical picture of the island Rapa Nui as it is portrayed in popular science and in ecohistorical literature of the university of Gothenburg. This historical picture states that the inhabitants of the island cut down a lot of trees in the process of transporting the big and heavy statues, moai, from the quarry to the platforms along the coastline of the island. During this process all trees disappeared and resulted in soil erosion. The cultivation was destroyed and brought hunger to Rapa Nui. The following rivalry for food led to a situation of war followed by a cultural collapse.

Kolbalansen vid olika skötselstrategier för skogen på Tagels fastighet.

Since the 19th century the concentration of CO2 in the atmosphere hasincreased by 40 percent as an effect of the use of fossil energy sources.Increased concentration of CO2 will likely lead to increased temperature,changes in precipitation, rising sea level and increased frequency of extremeweather like storm events. A step to reduce emissions of CO2 and mitigateclimate change, for the property of Tagel, can be to adopt new silviculturalstrategies and analyse which is the most effective. As a result of that, threescenarios was produced, business-as-usual (BAU), increased set aside landand energy. An introduction of windpower at Tagels estate (property) andeffects on carbon balance was also examined. By using the Heureka systemand LCA-analysis in this study, it showed that the scenario of increased setaside land was the most efficient way to reduce carbon dioxide (CO2)emissions for the analysed period of 100 years.

Skillnader i vatten- och avloppshantering inom EU : En jämförelse mellan Slovakien och Sverige

The management of water resources and waste water varies between the countries of the EU. For many years, a large part of the water in Europe has been contaminated by, among other things, insufficiently treated waste water and emissions from agriculture. The EU Water Framework Directive 2000/60/EC and the Urban Waste Water Directive 91/271/EEC are intended to harmonize fresh-water management and waste water management within the whole EU, aiming at safeguarding drinking water of good quality and a high quality of all water within the EU today and in the future. There are however some problems concerning the waste-water directive. One problem is the huge investment needed in Slovakia to fulfil the demands of the waste-water directive for waste-water management in larger communities (with more than 2000 inhabitants).

Östra Kvillebäcken En gröna stadsdelen? En fallstudie över Östra Kvillebäcken i Göteborg

The study is a case study about the green urban district, East Kvillebäcken, located in Gothenburg, Hisingen. East Kvillebäcken is the first urban district in Sweden with ambition to build sustainable according to the certification system Miljöbyggnad, which make it a pioneer project. The purpose is to investigate the upcoming and the meaning of the green urban district in East Kvillebäcken and show how public employees think the urban district can affect social, ecologic and economic aspects in the area. Dialogue interviews were done with four public employees, one estate agent and two residents. Local plans and other authority documents were used to get a deeper understanding for the case study.

Köpa jordbruksmark i Ukraina :

We have chosen to write our examination essay about Ukraine, we wanted to find out what kind of possibilities there is to run a farm there, and also find out what kind of problems that might arise. Ukraine is still heavily influenced by Russia and the legacy from the former Soviet Union. The agriculture today looks pretty much like it did before the collapse of the Soviet system. There are large governmental or cooperatively owned farms. The large farms have to deal with bad cash-liquidity and they often have trouble getting a hold of seed and artificial manure to their whole acreage.

Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening

The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.

Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)

Peat  lands  are  a  great  potential  resource  for  increased  forest  growth  in  Sweden, there  are  approximately  6.5  million  hectares  of  peat  lands,  whereof  around  70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste  land.  There  are  over  200  000  hectares  of  peat  land  that  is  already  drained and  wooded,  and  that may  be  suitable  for  fertilization.  Forest  production  on  peat soils  usually  requires  drainage  and  fertilization.  Dewatering  requires  ditching  the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The  purpose  of  this  work  was  to examine  the effects  of  potassium  fertilization  on the  growth  of  spruces  that  were  planted  on  drained  peat  land  and  how  different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance  transport  in  the  tree.  Potassium  is  also  important  for  the  carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter  resistance  of  many  species.  Potassium  is  not  found  in  any  organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was  left  without  fertilization.  All  plots  that  were  fertilized  with  potassium  grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality  estimation  of  wetlands  after  ditching  (dikningsbonitering).  The  plot  with most  potassium  produced  after  fertilizationaproximately  in  level  with  theoretical estimations.  Key  words:  Peat  land,  Fertilization,  Ditching,  Growth,  site  quality..

Hårdhetsvariation i grundvatten längs Badelundaåsen mellan Leksand och Avesta

Water hardness indicates the concentration of calcium and magnesium ions in water. Water with high concentrations of these ions is described as hard water and water with low concentrations is described as soft water. Water that is too hard or too soft can lead to technical and economical problems. In collaboration with Midvatten AB, groundwater hardness in the Badelunda esker between Leksand and Avesta has been mapped, and an attempt has been made to explain the variations. For this purpose, different GIS programs, such as ArcView, ArcInfo, IDIRISI, and one geochemical modelling program, PHREEQC, has been used.

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