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254 Uppsatser om Stream restoration - Sida 1 av 17

Två år efter restaurering:Vad har förändrats i bottenfaunan?

The aim of the study was to examine if the benthos in a restored portion of a small lowland stream south of Linkoping differed from two non restored reference areas two years after restoration. The reference areas were one stretch downstream and one upstream stretches of the restored stream. The benthic invertebrates were collected using standardized kick sampling. In order to classify the communities and estimate any differences, three different indices were exercised. In addition rank-abundance curves and checklists were used to get a picture of species composition.

Kan förändringar i bottenfaunan påvisas två år efter en bäckrestaurering?

The aim of this work is to analyze if a change in the benthic community can be detected two years after a restoration of a small stream. The samples were taken in a small stream at Tinnerö Eklandskap just south of Linköping. In addition to the restored area, two reference sites upstream and downstream of the restored area were sampled to compare to the restored site. The method used for sampling of benthic fauna in the stream was kick sampling. ASPT, Berger-Parker and Renkonen-indices were used to find out if there was any difference between the reference areas and the restored area.

Effekt av biotopvård på öringpopulationen i två vattendrag

I have done a follow up study of the restoration of two rivers, Röälven and Grundan, in order to evaluate the effects of the restoration on the endemic population of trout. Both rivers have been used for timber floating during many years throughout the 20th century, and because of this, had all obstacles such as rocks and wood parts removed. In 2004-2005 both rivers were restored, and rocks and wood were put back into the rivers. Spawning grounds were created and boulder dams were constructed to promote the streaming water. The result showed that the trout population of both rivers increased after the restoration, but also that the trout population of Röälven increased more than that of Grundan.

Vattendragsrestaurering i teorin och fiskinventering i praktiken : en litteratur respektive metodstudie

Running water-pathways have played an important roll in Sweden and frequently been manipulated. One profound change was made during the period of logging when streams were cleared from obstacles as big boulders, sharp bends and side-streams. Dams and different constructions gave control of the stream water and the streams became channel-like with a homogen structure. This interference gave problems for many fish populations and resulted in a shortage of feeding habitat, over-wintering habitat, spawning habitat, unnatural flow regimes, sedimentation, unnatural temperature fluctuations. Many of these historical changes of the watersheds are now subjects for restoration, ie., bring back the streams to what we believed it was before the change. However, what once existed in terms of complexity is now gone and difficult toreplace.

Utvärdering av den nationella databasen över åtgärder i vatten i fem svenska huvudavrinningsområden

Restoration projects are planned and carried out in order to reduce the impact due to anthropogenic influence and to achieve at least good ecological status according to the EU Water Framework Directive. The resilience effort of such restorations is however ambiguous. The aim of this study was to evaluate the potential of follow up restoration measures in Swedish lakes and streams. In particular, we visualized the geographical spread of restoration measures in Sweden and quantified the different types of measures that were implemented so far. Further, we evaluated the extent of sampling of biological factors before and after the restoration measures have occurred. For the purpose of our study, we used the recently compiled national database of restoration measures in Swedish lakes and streams.

Restaurerade ängs- och betesmarker : restaureringseffekten på växter och insekter

Semi-natural grasslands have a high biodiversity and host ecologically and economically valuable ecosystems and species. Restoration on these types of land is often done by removing trees and scrubs, mowing, grazing, changing the soil by removing nutrition or changing the structure of the ground. Another way of restoration is planting seeds of common grassland plants. By comparing 18 scientific publications I investigated if the restoration was affecting the plants in a positive way and if the effect was similar for insects. By comparing the publications, time seemed to have an important effect on insects. They needed time to recolonize restored areas.

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.

Ove Hidemarks restaurering av Kina slott - slottsarkitektens roll i teori och praktik

Uppsats för avläggande av filosofie kandidatexamen i Kulturvård, Bebyggelseantikvariskt program 15 hpInstitutionen för kulturvårdGöteborgs universitet2015:17.

3D-teknik som ett verktyg för bevarande - digital dokumentation och fysisk rekonstruktion

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2015:09.

Död ved i vatten - funktionella strukturer och dess påverkan på öring (Salmo trutta, L.)

The background to this work was to see if there was a connection between large woody debris (LWD) and the presence of brown trout in our Swedish forest streams. Previous researches by Degerman et al. (2004) have shown that there is a strong correlation between the amount of dead wood and the presence of brown trout. The goal was then to find a way to restore, maintain and increase the trout habitats by constructing and adding manmade wooden structures that would mimic natural deadwood and its features in flowing water. The inspiration was partially taken from a water restoration program in the Klamath River of northern California, USA.

Flödesoptimering på sjukhuslaboratorium: En praktisk implementering av lean

This study has investigated the possibilities of implementing lean in a division of a hospital in Stockholm. The goal was to reduce the lead time for the patient to get his diagnose by implementing lean in the two production flows of this division. In order to accomplish it, a complete map over the value stream has been done. With the help of the value stream map and lean theory a list over the processes in contradiction with lean has been made. Finally propositions to implement lean and by this way reduce the lead times in this stream have been made out.

Value stream mapping i praktiken : En fallstudie på Light My Fire

Titel: Value stream mapping in practice ? A case study at Light MyFireAuthors: David Rydman and Tomas ÖnnemarMentor: Veronica Ülgen SvenssonExaminer: Åsa GustafssonBackground: Companies push their prices in today's markets to be competitive, which means that companies need to find ways to reduce costs while maintaining profits. (Cudney, 2009) According to Bergman and Klefsjö 2007, the basic rule of quality improvement says "there is always a way to achieve higher quality at a lower cost". One way is to improve a company's processes to get a more efficient flow and improvements that may cut costs. (Bergman & Klefsjö, 2007) Why it's important to look at the processes are that they often contain waste that can be eliminated.

Miljövärdeflödesanalys av Risifruttiproduktionen : En utvärdering av värdeflödesanalys och miljövärdeflödesanalys

This report is the result of a thesis work carried out on the Risifrutti production at the company Procordia Food AB. The thesis is at a master level and is the final work for the author to receive a Master of Science in Innovative production at Mälardalen University. The thesis comprises 30 credits and has lasted for 18 weeks. The thesis is mainly a research on whether it is possible to perform an Environmental Value Stream Map (E-VSM) in a food processing industry and an evaluation if the tools E-VSM and Green Performance Map (GPM) are useful in this type of industry. An extra part to this research is to use the results from the E-VSM and give Procordia Food AB information on improvement potentials in the Risifrutti production. The author has found it difficult to collect some of the quantitative data to the E-VSM, mainly regarding energy, but by using the Value Stream Mapping (VSM) tool and other Lean tools the author was able to identify and quantify several wastes in the Risifrutti production. Recommendations for improvements based on these wastes have been given to the company. In the research part of this report the utility of the Value Stream Map, Environmental Value Stream Map and Green Performance Map in a food processing industry have been analyzed. The author has found that the Value Stream Map has been a useful tool since waste and unevenness in the tact of the production has been identified. The Environmental Value Stream Map and the Green Performance Map are also great tools when a company wants to analyze their environmental impact and then invest in environmental improvements. However, no profound energy analyzes has been done in the Risifrutti production because of the lack of energy meters for steam, electricity and compressed air in the production lines..

Våtmarker för näringsretention i Lillån : var bör de ligga och vilken effekt kan vi förvänta

Construction of wetlands in the agricultural landscape may reduce nitrogen and phosphorus transfer to streams, thereby reducing the eutrophication of lakes and seas. The agriculturalstream Lillån, a tributary to stream Sagån, ends up in Lake Mälaren and is transporting large amounts of these plant nutrients. The aim of this study was to estimate how hypothetical wetlands of different size and location may reduce nitrogen and phosphorus load from stream Lillån. Estimated nutrient retention in several small wetlands was compared to retention in a single large wetland based on existing data from the agricultural stream and from a nearby smaller stream. Retention in the stream was suggested to decrease along with the nutrient concentration in the water.

Restaurering med naturlig cement

Title in original language: Restaurering med naturlig cementLanguage of text: SwedishNumber of pages: 72Keywords: Natural cement, roman cement, restoration, mortar.

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