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367 Uppsatser om Wind erosion - Sida 5 av 25

Predicting spawning bed erosion and longevity : a case study in tributaries to river Vindelälven, northern Sweden

Timber floating operations in Scandinavia during the 19th and 20th centuries has contributed to severe negative impacts on riverine ecosystems. Increase in water velocity and lack of stream bed heterogeneity as a result of stream channelization lead to increased bed load transport. Since availability and recruitment of new suitable spawning substrate in Scandinavian watercourses is sparse, spawning habitats for salmonids has become a scarce commodity. Lately, increasingly more attention has been given to the recreation and improvement of brown trout (Salmo trutta) spawning habitats in restoration projects. While much of the research on spawning habitat has been focused on evaluation of the influence that the constructed spawning grounds have on fish populations, few studies have been conducted to evaluate the persistence of these constructions over time. I evaluate erosion of constructed spawning beds as an effect of sediment transport attributable to water discharge.

Nätanslutning av vindkraft : vindkraftsbranschens aktörers perspektiv på nätanslutning och tariffer

Wind power is a growing energy sector in Sweden. However, it still represents only a small part of the total electricity production, about 0.7%. In order to create good conditions and to facilitate the establishment of wind power in Sweden, the government has for example, created a national centre for wind use. The objective has been to reach the governmental goal, which is an expansion of wind power by 10 TWh by year 2015 compared to the level in 2002. The Swedish electricity market was deregulated in 1996 which refers to the introduction of a competitive market in electricity production and trade.

Vindkraftetablering och uranborrning i Dalfors-Dalarna; Acceptans bland närboende

The dependency of fossil fuels has to decrease in order to reduce emissions of green house gases. Wind turbines generate electricity with low environmental impact, but the local opinion in Sweden is sometimes an obstacle to new developments. The acceptance of nuclear power increases at the same time. Mining uranium is once again on the agenda and prospectors are currently drilling for uranium. This cross-sectional study deals with acceptance of wind farms and uranium drilling.

Vindkraftverkens nedmonteringsprocess i Sverige

The first commercially produced wind turbines in Sweden are starting to reach theend of their lifetime after approximately 25 years of producing energy. The cost fordismantling the turbines, according to Ardefors et al. (2009), is calculated to be 1-2 %of the total investment of the wind turbines. The purpose of this master thesis is tomap the dismantling process of wind turbines in Sweden and try to find a sustainablesolution for the future.To make sure that a correct dismantling process takes place, and that the financialaspect is covered, a proposal for a financial guarantee is worked upon. A nationalunanimity will be created through a financial guarantee and the risk will be minimalof a third party getting afflicted.Studies of literature and interviews have been carried out.

Små skogliga vattendrag i Värmland - Generell beskrivning, förekomst av traktorspår samt spårens inverkan på bottenfaunan :

Modern forestry requires a high degree of machine traffic for clear felling and scarification operations. The machines most frequently used are big and the traffic often results in tracks on the forest ground. There are many small streams running through a forest, in connection to logging operations, machines might cross these frequently. These crossings could result in the erosion of fine particulate inorganic matter, which ends up in the stream. The aim of this thesis was to give a general description of small forest streams of order-one in the county of Värmland and to determine the frequency of machine tracks in small streams.

Metoder att förhindra nedisning av vindkraftverksblad

ABSTRACTMany wind turbines have problems with icing and there is still no effective method to de-ice without stoppage of production and power loss. Here I therefore consider other methods than those available today, and particularly, I consider how these methods could be applied to wind turbines of the company Oxel. A surface where the water droplets do not attach might be the basis for a useful method. If no water attaches, no ice could form. To accomplish this a hydrophobic surface is nessesary, for example wax.

Vindskador vid stickväg i 1:a och 2:a gallring i Boxholm, Östergötland : i stormen Pers fotspår

Wind damages next to strip roads in 1st and 2nd thinning in Boxholm, Östergötland Anneli Fransson, SLU, inst f sydsvensk skogsvetenskap, Examensarbete no 108 Wind damage is something we are all familiar with since the storms Gudrun (2005) and Per (2007). Research about strip roads and wind damage is very limited. It is commonly known that the trees next to the strip roads more often fall whit heavy winds, and the purpose of this thesis was to verify this statement. Data was collected from first- and second thinnings at Boxholms Skogar AB, Östergötland. In first thinnings data was collected from both spruce and pine stands and second thinnings only data from spruce stands was collected.

Markvattenhalt och temperatur i sandig jordbruksmark vid Ilstorp, centrala Skåne : en mätnings- och modelleringsstudie

Vinderosion på jordbruksmark har länge varit ett välkänt faktum trots att någon utförligare undersökning om dess omfattning och skadeverkan inte tidigare genomförts. Mot bakgrund av detta har därför ett nordeuropeiskt projekt, WEELS (Wind erosion on European Light Soils), dragits i gång som syftar till kartlägga vinderosionen på sandig jordbruksmark i norra Europa och som man i slutändan hoppas ska kunna resultera i en vinderosionsmodell. Detta har genomförts med SOIL modellen, en matematiskt fysikaliskt baserad modell för simulering av vatten och värmeflöde i en skiktad jordmånsprofil..

Lähäckar för minskad vinderosion och andra ekosystemtjänster

Människans näringar och kulturer har orsakat landskapsförändringar som på många håll i världen lett till flera ekologiska konsekvenser som erosion liksom övergödning av vattendrag och hav. Skogsbruk såväl som jordbruk har därutöver resulterat i stora utarmningar av den biologiska mångfalden på jorden. Sedan en tid har jordbrukets negativa konsekvenser fått alltmer uppmärksamhet inom bland annat politik, forskning och näringsliv, varav somliga människor aktivt försökt stoppa det negativa händelseförloppet som manifesterat många av världens odlingslandskap. Diskussioner som innefattar ekosystemet och dess så kallade tjänster för människans såväl som andra organismers överlevnad och välbefinnande erhåller därutöver mer och mer fokus i strävan mot miljövänligare alternativ för storskalig odling. I sökandet efter mer ekologiskt sunda odlingssystem har intresset igen väckts för agroforestrysystem, som kombinerar vedartade växter med vanligt förekommande grödor. Etableringen av lähäckar på respektive intill odlingarealer i Skåne kan bidra med flertalet ekosysystemtjänster vilka bevisats stoppa ex.

Vindkraft och rennäring

The Swedish Parliament has decided to increase the share of electricity produced by wind power. The same parliament has decided that the Sami have the right to herd reindeer over 50% of the country's land area. In this literature review the potential impact wind power development and associated infrastructure may have on reindeer husbandry conditions are examined. The unique physiology of the reindeer enables it to live out of grazing in the arctic climate in the north of Sweden. For reindeer husbandry to be long-term productive and sustainable, it is important that there is enough land for grazing. The research available on how reindeer are disturbed by human activities such as roads, mines, hikers, etc., clearly indicates that the reindeer avoids areas close to such disturbance.

Kost-och munhygienvanor hos en grupp skiftarbetare : Tvärsnittstudie

Introduktion: Erosionsskador är ett växande problem bland barn, ungdomar och unga vuxna. Dental erosion har en multifaktoriell etiologi som består av endogena och exogena orsaker. Att erosionsskador på tänderna ökar kan bero på den höga konsumtionen av sura drycker bland barn, ungdomar och unga vuxna. Personer som idrottar kan löpa risk för dental erosion på grund av frekvent intag av sura sport/energidrycker men även till följd av påverkat salivflöde. Få studier har undersökt fotbollsspelares kunskap om dental erosion och dess konsumtion av sport/energidryck.Syfte: Att studera kunskapen om erosionsskador bland en grupp fotbollsspelande kvinnor och män.Frågeställningar: Vilken kunskap har fotbollsspelande kvinnor om erosionsskador? Vilken kunskap har fotbollsspelande män om erosionsskador? Vilken konsumtion har fotbollsspelarna av energi/sportdryck?Metod: Studien är en kvantitativ, empirisk, tvärsnittsstudie.Resultat: Totalt deltog 44 personer i studien, 29 kvinnor och 15 män.

Rätt gåva för rätt tillfälle

This master thesis is a study of the Swedish hydropower capacity to balance wind power. The Swedish government has decided that it should be possible to produce 30 TWh from wind power in the year 2020. The Swedish municipalities have to have plans for wind power plants with total yearly generation of 30 TWh. Wind power is an variable energy source that needs to be balanced by other energy sources. In Sweden the Swedish hydropower can be used for balancing a large scale introduction of wind power.

Uljabuouda vindkraftpark turbinmodellering och stabilitetsanalys

This master thesis has been performed at Solvina in Gothenburg for Skellefteå Kraftand Vattenfall Eldistribution. The aim of it is to investigate the consequences of theinstallation of a wind power plant on the mountain Uljabuouda in the vicinity ofArjeplog. Especially the impacts on voltage and transient stability are examined.Furthermore, the amount of extra strain on the voltage regulation equipment and theneeds for increased regulation capabilities are looked into.The wind power plant is planned to be built by Skellefteå Kraft and connected to a130 kV grid owned by Vattenfall Eldistribution. The work comprehends the followingmain parts:- Theoretical studies aimed at wind turbines and power system stability issues.- Modelling of the type of wind turbines assumed to be built on Uljabuouda.- Simulations of different operation cases and analysis of the simulation results.The results from the simulations show that, as far as voltage stability and extraworkload on tap-changers are concerned, the wind power plant does not, in anysignificant manner, worsen the present conditions. The problem of overloading theline between Arvidsjaur and Vargfors is also minor.

Förstudie för en vindkraftpark på Malmölandet i Norrköping : En undersökning av förutsättningarna för en vindkraftpark på ett sen tidigare planerat område

This is a feasibility study that examines various aspects of building a wind farm on Malmön in Norrköping. The feasibility study deals with interests of conflict, park design, electrical connections, production calculation, financial calculations and operating- and timetable.The report is divided into two distinct parts. First a theoretical part, which deals with conflicting interests, park design and electrical connections. Second a part with simulations dealing with production calculations, and financial calculations.Opposing interests are mapped so that problem areas can be found, and help put focus on the right places at a future environmental impact assessment (EIA). There are a number of areas where planners have to assess on an EIA, this thesis point on the most important areas.

Projektering av vindkraftspark i Juddhult, Småland

The aim with this study was to collect fundamental information, and to plan, a windpower farm in Juddhult , Småland in southern Sweden. The goal is to collect the bestavailable projecting planning support. The pieces of this projecting planning supportthat will be presented is; Environmental Consequence Description (MKB), productioncalculations, comparisons between different plant types, economic calculations, evaluatethe economy and give some farm design suggestions. The imagined wind farm will belocated in forest environment and which may cause a number of new problems. Specialinterest that will be affected, where special consideration because of the forestenvironmental is requested is, hunting, wetlands, ancient monuments and windturbulence.

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