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79 Uppsatser om Coarse woody debris - Sida 2 av 6

Buskröjning längs skogsbilvägar : en produktivitetsstudie av två kättingslagor

To regularly remove woody vegetation along the roadside of forest roads is an important part of the road maintenance, since the vegetation binds moisture in the road side and, thus, the removal makes the road drying faster with results in improved bearing capacity. Vegetation removal also makes it easier to upgrade the road by material recycling from the ditch and, moreover, the visibility along the road is maintained.The aim of the study was to evaluate what type of chain flail is the best and most cost-effective for removal of different kind of woody vegetation along forest roadsides.Time studies were made on two chain flails when removing woody vegetation in three different classes; easy-, middle- and heavy shrub removal. The studied flails were one light and rather simple flail named Optimal M160 and a heavier and more advanced flail named Slagkraft H210. The removal was made according to Holmen Skogs? specification and the quality of the cleaning was measured by objective belt inventory.The productivity was higher with the heavy flail within all cleaning classes.

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.

Montessoripedagogiken i kombination med Lgr 11

Min uppsats handlar om Woody Allens skildring av staden. Det är inte New York denna uppsats handlar om, utan om de europeiska storstäderna London, Barcelona, Paris och Rom. I dessa städer har Woody Allen spelat in fem filmer. Dessa filmer är Match Point (2006), Scoop (2007), Vicky Cristina Barcelona (2008), Midnight in Paris (2011) och To Rome With Love (2012). Det ryktas även att hans nästa filmprojekt kommer att utspela sig i en europeisk storstad.  Varje film visar utvalda sidor av respektive stad.

Förbränning av pellets framställda av defibrerad granråvara :

Fuel pellets are in Sweden mainly produced from sawdust and cutter shavings. Before the pelletising process the raw material is dried to attain consistent moisture content and ground up in a hammer mill. In the densification process (pelletising) the ground material is forced through holes in a rotating die. This heats up the wood particles which cause them to soften and self bond. After the process the pellets are cooled, sieved and bagged. The milling process creates a wide range of particle sizes.

Vattenvård vid slutavverkning : före och efter vattenvårdsutbildning på Stora Enso Skog, distrikt Siljan

In 2006, Stora Enso Skog implemented an education program in water management for harvester operators, timber purchasers, cut block planners and supervisors. The focus of the program was creating stream crossings with minimal harm to the stream and the surrounding riparian area. This main purpose of this study was to determine the difference in work procedures before and after participating in the program. The methodology consisted of field studies and interviews with harvester operators and their supervisors. The field study looked at how the streams had been crossed concerning the number of crossings, visible damage to the stream and/or the riparian area made by the machines. Biological parameters such as the width and dept of the stream and amount of large woody debris in the stream were also measured. The field result from 30 harvesting sites showed no significant difference between sites that had been harvested before or after the education program. But the harvester operators and their supervisors experienced an increased concern for watersheds after the educational program.

Fosforavskiljning i reaktiva filter vid småskalig avloppsrening

An excessive input of nutrients to lakes and other water bodies has created a problem with eutrophication in Sweden. Untreated, or partially treated, domestic sewage is a major source for discharge of phosphorus (P), which is the nutrient most frequently responsible for eutrophication of most fresh waters and the Baltic Sea. The waste water can be cleaned by filter materials, which have a high P-retention ability and which after saturation may be used as fertilizers. Four potentially suitable filter materials were tested in batch- and column experiments in this study. In the batch experiments, the following materials were shaken with waste water in time series ranging from 5 seconds to 60 minutes: coarse (1-4 mm) and fine (0-2 mm) Polonite® (heated bedrock from Poland); Filtralite® (light expanded clay aggregates with limestone added before burning); water cooled blast furnace slag (BF-slag) and BF-slag mixed with 10% burned limestone.

Fotogrammetrisk analys av kornstorleksfördelningeni erosionsskydd vid kraftverksdammar

This master thesis was made to investigate the possibilities of using the Matlab-basedsoftware Basegrain to determine grain size distributions of erosion protections onhydropower dams. Basegrain is a photogrammetric tool developed to generate grainsize distributions and other information about coarse flood sediments by analyzing adigital photo of the stone bed. The investigation was made by validating the ability forBasegrain to assess grain size distributions of various materials smaller than the blocksused in an erosion protection by comparing sieving results or manual measurementswith the results obtained by the program. A statistical comparison was then made bycomparing the results from sieving and the program. The possibilities of using thesame method on existing hydropower dams were then investigated by determiningwhether the method was practically viable or not.The results showed that Basegrain generated grain size distributions for coarse gravelthat were very close to the sieving results.

Svensk plantskoleproduktion 2003 :

This work consists of two studies. One is based on an inquiery to nurseries with production of woody plants, and the other on visits to gardencenters, primarily in Skåne but also in Stockholm. Inquieries where sent to 87 nurseries, 48 of them replied. The purpous of the inquiery was to make a thorough investigation of the ligneous production at the Swedish nurseries, what is produced and in what quantities. Within the inquiery was also a thorough look at the fruit tree production. This to be able to conclude what cultivars that are produced and how large part of that production that is certified according to the Swedish Board of Agriculture (SJV).

Påverkan av tillskott av död ved och reducerat evertebratnedfall på öringens (Salmo trutta L.) diet i en skogsbäck

Det svenska skogsbruket har lett till minskade vedmängder i skogsbäckarna. Detta kan undvikas genom att orörda kantzoner lämnas. Kantzonsvegetatioen har även visats påverka nedfallet av terrestra evertebrater, vilket visats minska andelen terrestra evertebrater i laxfiskars diet. Ofta lämnas dock inga kantzoner. Vedmängden kan återställas genom ett vedtillskott.

Påverkan av tillskott av död ved och reducerat evertebratnedfall på öringens (Salmo trutta L.) diet i en skogsbäck

Det svenska skogsbruket har lett till minskade vedmängder i skogsbäckarna. Detta kan undvikas genom att orörda kantzoner lämnas. Kantzonsvegetatioen har även visats påverka nedfallet av terrestra evertebrater, vilket visats minska andelen terrestra evertebrater i laxfiskars diet. Ofta lämnas dock inga kantzoner. Vedmängden kan återställas genom ett vedtillskott.

Rening av avloppsvatten efter skärprocess

ABB I-R Waterjet Systems combines the robotics and motion expertise of ABB Flexible Automation with high-pressure intensifier/pumping technology from Ingersoll-Rand to provide and continue to develop innovative waterjet cutting systems for global markets. The purpose of this assignment is to develop a process water purifier. The purifier should be applicable as an option to ABB I-R?s production cell Cutting-Box. At first hand the process water should be purified well enough to let out in the municipal sewage system, but the ultimate solution is purifying the process water to the range that recycling is possible.

Vilken preferens har tjockskalig målarmussla (Unio crassus) för bottensubstrat och vattenhastighet i Storån, Östergötland?

The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.

Rening av avloppsvatten efter skärprocess

ABB I-R Waterjet Systems combines the robotics and motion expertise of ABB Flexible Automation with high-pressure intensifier/pumping technology from Ingersoll-Rand to provide and continue to develop innovative waterjet cutting systems for global markets. The purpose of this assignment is to develop a process water purifier. The purifier should be applicable as an option to ABB I-R?s production cell Cutting-Box. At first hand the process water should be purified well enough to let out in the municipal sewage system, but the ultimate solution is purifying the process water to the range that recycling is possible. When investigating the different principle of purifying water, a research of different products and their manufactories was done. These different products were compared and the principle of filtration was the most applicable, as most of the products were designed for far larger applications. As the process water contains quite large amount of particles, it is necessary to perform the filtration in different steps. The process water purifier is therefore composed of a module of coarse filtration and one of micro filtration. In the module of coarse filtration the mainly amount of fibres and particles are eliminated. They are kept back in the container unit with the larger fragments and dumped with these when the container is emptied. In the module of micro filtration the filtration is performed in two steps. In the first step particles larger than 50?m are eliminated, in the second step the micro filter is setting the range of purifying, in this case 10?m.

Död ved i gallrad skog och nyckelbiotoper : en jämförelse av habitatkvaliteter för vedlevande lavar och mossor

A high amount of dead wood is one of the most important prerequisites for high biodiversity on forest land in Sweden. Dead wood is most abundant in young forests, thinned forests, woodland key habitats and protected forest land. In old-growth forests most of the dead wood consists of logs and snags, whilst in managed forests a huge proportion of dead wood is made up of logging residues like stumps and FWD, fine woody debris (< 10 cm diameter). All these different types of dead wood may serve as substrates for epixylic bryophytes and lichens. However, few studies have been conducted on the relative importance of these different fractions of dead wood for the occurrence of bryophytes and lichens, especially when considering dead wood on thinned forest land.

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.

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