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206 Uppsatser om Riparian zone - Sida 1 av 14

Den bäcknära zonen vid små skogliga vattendrag i Värmland : generell beskrivning, förekomst av traktorspår samt kvicksilverhalter i körpåverkat ytvatten

Forest streams and the associated Riparian zones are sensitive to disturbances and changes that occur within these riparian areas. Particularly sensitive are small streams of low order, which will have large impacts down-stream. The disturbances that occur in the Riparian zones are reflected quickly in the stream. Driving with forestry machines in the Riparian zone will have detrimental effects to the soil and water. Driving the machines will lead to changes in the mineral soil composition, resulting in the reduction of porosity, less infiltration, compaction, and an increased bulk density.

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.

En studie av sedimenttransport, död ved och kantzoner längs två vattendrag i Kilsbergen - från skog till slätt :

Headwater streams are affected by anthropogenic impacts at multiple scales. One aspect of human impact is sediment transport associated to the abundance of stream structures as large woody debris and the composition of the Riparian zone from forest to agricultural landscapes. Riparian buffer zones and stream structures like dead wood are considered as generally important structures for protection against an increasing amount of sediment particles in the water. Hence, in this study these structures were quantified in thirty different stream segments on land and in the water. To measure the transport of sediment Whitlock-Vibert boxes were used in three different types of landscapes; forest, transition and fields. The boxes were left in the stream segments for three months, the taken up and dried and weighed. The results showed that the transition-land in Frösvidalsån had the highest sediment transport. The second highest transport of sediment was in Blackstaån at the fields.

Påverkar jordbruk flödet av akvatiska insekter till land? : Effekter av jordbruk på akvatiskt tillflöde till land vid norrländska bäckar

Streams and Riparian zone are closely linked by reciprocal flows of energy and nutrients. A large part of the transportation from water to land is in form of emerged aquatic insects. Conversion of land from forest to agriculture can greatly affect aquatic ecosystems, and due to the close link, also affect the adjacent terrestral zone. Investigating how the presence of agriculture in the surrounding area affects amounts of emergent aquatic insects gives an indication on how agriculture, in turn, may affect the terrestral enviroment. The study was preformed alongside ten streams in northern Sweden; five in landscape transformed by agriculture and five in undisturbed forest areas.

Död ved i ett referensvattendrag

The purpose with this study is to find out how much dead wood we can expect us to find in a Russian reference river and compare with studies from Swedish streams. Dead wood are an important structure for the biodiversity in forest streams, studies have shown that population of trout can increase with up to 300 % when the amount of dead wood are increasing from 0 to 8 ? 16 LWD (Large woody debris)/100 m2. Dead wood are also an important structure for the stream character, formations of dams and pools which are important habitats and reproduction areas for salmon and brown trout. The study where taken place in tributaries to the Russian river Varzuga in the North West part of Russia outside Murmansk. Varzuga has low impact of human activity and is considered to be a reference river to rivers in northern Sweden.

Grodsamhällen längs vattendrag på Borneo : En identifiering av habitatkaraktärer viktiga för diversitet och abundans av grodor i tropisk regnskog

The stretch from the Riparian zone of a major river, through the mouth and upstream in tributaries forms a range of differing habitats. The aim of this study was to investigate the effect of these different habitats on the riparian frog community in primary rain forest in Borneo; i.e. examine whether any gradients could be demonstrated in terms of species composition, diversity and density of frogs, as well as which environmental characteristics that seem to be of most importance in forming habitats of high conservational value. A major river, Segama, and three of its tributaries were investigated. The surveys were carried out at night by searching for frogs visually and acoustically along the streams, from the shore of the Segama river and 400 metres upstream in the tributaries.

Om behovet av ett avrinningsområdesanpassat skogsbruk

The Swedish forest have about 100 000 km of watercourses and it?s an important structure in Swedish landscapes and catchments. In some of the watercourses lives spieces like the freshwater pearl mussel (Margaritifera margaritifera) and brown trout (Salmo trutta) which both are sensitive for inteference from the forestry. The new EU water framework directive has a goal that all surface water will have high or good ecological- and good chemical status at latest by the 22nd December of 2015. The study has been made in the catchment of Håltjärnsbäcken and it is from a national perspective one of the most valuable streams in Sweden and which also have been included in a LIFE-project. The catchment is situated within the Eco-park of Malingsbo-Kloten and managed by Sveaskog AB.

A First Effort to Visualize Knowledge of a Region? A visualization of Öresund & Shenzhen in the perspective of Knowledge Innovation Zone

We have through our theoretical framework been able to create a simplified measuring tool for a KIZ; the S-TKL. We have found that the S-TKL is possible to implement on the Öresund Region but with some flaws. Even though the Öresund Region has implemented the mindset of a KIZ, accurate statistics are in some areas hard to find. We can also through our empirical findings say that it is difficult to use the S-TKL on Shenzhen. The data we have found gives a good indication of both of the regions.

Konsten att mäta tjänstekvalitet : En utvärdering av tre instrument för att mäta tjänstekvalitet i kollektivtrafiken

The purpose of this study is to analyze and evaluate the suitability of the three instruments SERVQUAL, SERVPERF and Zone of tolerance to measure service quality, from the respondents' perspective. This study has been carried out by a quantitative method in which respondents answered three questionnaires, which was based on the three instruments. The SERVQUAL instrument is a revised version based on criticism by Carman (1990). It is based on the five dimensions; reliability, responsiveness, assurance, empathy and tangibility, with 22 items in which each dimension is associated with a number of items. SERVPERF is the instrument most similar to SERVQUAL and is also composed of the same five dimensions.

Bangenerering för industrirobot med 6 frihetsgrader

This thesis studies path generation for industrial robots of six degrees of freedom. A path is defined by connection of simple geometrical objects like arcs and straight lines. About each point at which the objects connect, a region, henceforth called a zone, is defined in which deviation from the defined path is permitted. The zone allows the robot to follow the path at a constant speed, but the acceleration needed may vary. Some means of calculating the zone path as to make the acceleration continuous will be presented.

Svikna löften? : Fem unga män på en anstalt i Sverige och deras upplevelse av sin egen skolgång.

This study is about inmates, who reflect upon their time in school, their experiences of school and how different things have influenced and affect them later in life. The aim with this study is to examine how different kinds of school related issues have affected the inmates in different ways. The aim is also to look at how school can spot in early years, children within the danger zone and provide for those children, so that they can be helped in different ways and so that they can be able to achieve different in life, not to end up becoming criminals later in life.The main questions in this study are:How did the chosen inmates experience their time in school?Can you by looking at research tell that these persons already in their childhood were children within the danger zone?What kind of school related issues could have contributed to a criminal lifestyle later in life?The result of this study shows that all five have been children within the danger zone. In all five cases there have been school related issues that have affected those men.

Developer zone ? Kriterier för uppsättning och användning av en developer zone

Denna studie berör olika developer zones som idag drivs av företag i Sverige, och om hur dessa är uppbyggda. Den tar upp de problem som dessa företag har stött på, samt vad man ska tänka på vid uppstart och användning av en developer zone.Att låta sin developer zone vara helt öppen eller helt stängd är inte det mest optimala sättet eftersom man i den helt öppna versionen låter sin information vara tillgänglig för allt och alla. Den helt stängda versionen stänger ute kunskap från developer zonen. Genom att sätta upp en developer zone med båda delarna, dvs. en öppen del för utvecklare som intresserade att utveckla innovativa tjänster/produkter och en stängd del för företag som tillsammans med ägaren av developer zonen har ett ekonomiskt intresse, så uppnår man en mer kontrollerad form.

Fjällfåglar : En jämförande studie från dal till topp i ett nordligt och sydligt svenskt fjäll

Title: Mountain birds ? a comparative study from valley to mountaintop in a northern and southern Swedish fjeld  Author: Kristian Zackrisson Abstract Main aim in this study was to increase the knowledge about birds in the Swedish mountain area. Three questions were asked: 1) Which bird species can be found during the breeding season along a low mountain slope from a forested valley to a mountaintop with bare mountain environment? 2) Do the number of species and individuals differ in different elevation zones? 3) Is the composition of bird species along a low mountain slope the same in the Kebnekaise mountains inLaplandand the Grövelsjön mountains in Dalarna? Bird census in two study sites located in the Kebnekaise mountains and the Grövelsjön mountains and subsequent analysis of the results from the bird census was the main parts in this study. Totally 20 bird species were found along a low mountain slope in the Kebnekaise mountains.

Göteborgs blå struktur : med studie av Osbäcken

Gothenburg municipality has a lot of natural water. This paper enhances the function and importance of water in the city. It also deals with the problems of sewage water and flooding. Gothenburg has reached an advanced stage of water planning. By developing a Waterplan, the municipality highlight that water has an important position in the urban planning.

Stadsplaneringsideal. Med den periurbana zonen i fokus - dess potential för den hållbara staden

To be able to plan for the expansion of a town, one needs a vision of the future appear-ance of the town. It is the current issues (social situation, supply and demand, political control etc.) which decide what the ideal for town planning is. This is turn is the steering factor of the physical structure of the town. Therefore, the town's structure is decided by these ideals.In this report, I will present planning ideals that have historically been, and which criticisms that have been directed towards them. With reference to these issues, I will present those guidelines and ideals we have today for planning of our towns.

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