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535 Uppsatser om Soil contamination - Sida 30 av 36
Indirekta effekter på marklavars abundans och diversitet vid ökad kvävehalt i marken : en jämförelse mellan opåverkad och lågintensivt brukad mark
Lichens are adapted to bright and sparse forests on oligotrophic ground. Due to a slow growth rate and high light demand lichens will suffer from competition in eutrophic environments. Therefore, lichens have disappeared from managed forests where the forest industry has increased the productivity. A reduced abundance of lichens will affect both biodiversity of the forest and the reindeer winter graze lands. It is important to understand how and for how long fertilization affects the abundance and diversity of lichens in order to protect lichen rich ecosystems.
We have registered the biomass and number of lichen species in eight plots (four nitrogen rich and four nitrogen deficient) and compared fertilized Sami settlements with their oligotrophic surroundings in the nature reserves of Tjeggelvas.
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.
Lerlagers tätande förmåga och inverkan på transporten av klorerade lösningsmedel i förorenade områden.
Detta examensarbete syftade till att undersöka om lera kan förhindra en spridning av klorerade lösningsmedel ned till grundvattnet samt vid vilka hydrogeologiska förhållanden som lera har störst potential att vara tätande. Det övergripande målet med arbetet var dock att bidra till att tydliggöra definitionen av och förbättra kunskapsläget om tätande jordlager på Sveriges Geologiska Undersökning (SGU).Sju förorenade områden där klorerade lösningsmedel påvisats i jord och/eller grundvatten valdes ut till en jämförande fallstudie. Samtliga områden var belägna inom 750 m från något av SGUs lokalkarterade grundvattenmagasin och lera överlagrade helt eller delvis grundvattenmagasinet på platsen. Resultatdata i form av jord- och grundvattenprov från tidigare undersökningar av områdena lagrades in i databaser på SGU. Spridningen av klorerade lösningsmedel på varje område analyserades sedan genom att titta på var i området olika koncentrationer uppmätts och hur koncentrationerna förändrats med djupet.
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.
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.
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.
Mikrobiella hot mot nordiskt dricksvatten : En studie av mikrobiella föroreningar i dricksvatten i Norden samt en utvärdering av olika reningsprocesser
Den största akuta risken inom dricksvattenförsörjningen är vattenburen smittspridning. Dricksvattenrelaterad smittspridning förekommer i störst utsträckning i utvecklingsländer med dåliga sanitära förhållanden. Under 2000-talet har de nordiska länderna drabbats av flertalet dricksvattenburna sjukdomsutbrott vilket har lett till att mikrobiella föroreningar uppmärksammats som ett problem även i Norden. För att säkerställa att det dricksvatten som distribueras är av god mikrobiologisk kvalitet krävs att säkerhetsbarriärerna i vattenverket är tillräckligt effektiva för alla typer av mikrobiella föroreningar. Vissa mikroorganismer har uppmärksammats som mer tåliga mot olika desinfektionsmetoder, till exempel klorering, än vad som tidigare varit känt.
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..
Påverkan på Valboåsen från verksamheter inom Svedens industriområde samt närliggande områden : hot mot grundvattnets kvalitet och kvantitet?
The aim of this work was to find out what potential contaminants from roads, residential area and businesses within Svedens industrial area that can affect groundwater quality and quantity. Data collection was from SGU, VISS, internal material from Gävleborg county Administrative Board and Gävle municipality archive. GIS software ArcGIS was used to create the map images in the work.
The studied area is located approximately ten kilometers west of Gävle city and consists of the esker Valboåsen, which is a glacifluvial deposit that in its central parts consist of coarse material that is overlaid by sand, clay and silt. North of esker Valboåsen there are the river Gavleån which has an inflow to the groundwater in the esker. This inflow represents the largest part of the groundwater recharge.