Sökresultat:
192 Uppsatser om Thick-shelled river mussel - Sida 4 av 13
Hur ser lavars fördelning ut runt stammen på ek, och påverkas den av trädets storlek och dess närmiljö?
The aim of this study was to describe preferences of geographic direction of ten, oak-living epiphytic lichen species and how they responded to sun exposure, nearby bushes and trees, bark fissure depth and circumference. The frequency of every species was recorded in arcs of ten degrees around the tree at a height of 130 to 180 cm above the ground. An estimation of the amount of every species in every arc was also recorded. To analyse how the distribution of the lichen species responded to the different factors their concentration for every tree was plotted against the four factors. The distribution of Cliostomum corrugatum had a positive response to high sun exposure and a negative response to a thick layer of bushes and trees.
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.
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.
Elevers förståelse av fotosyntesen och dess koppling till andra organismer
The effects of the deregulation of the electricity market 1996 in Sweden on short-term hydropower regulation are unknown. This report investigates patterns in subdaily regulation in the Ångerman River Basin during the period 1993-2011. Differences in subdaily flows and zero flow events between the periods 1993-1995 and 1996-2011 were studied by analyzing hourly data from 8 regulated and 8 unregulated locations with four subdaily flow variation indices. No correlations between the market deregulation and the regulation intensity in the Ångerman River basin were detected. The number of days natural ranges of variability were exceeded and the magnitude of subdaily variation were significantly higher at regulated locations.
Den homosexuella mannen i tragedi och melodram. En jämförelse av homosexuell identitet och genre i teaterpjäserna The River and the Mountain och The Boys in the Band
Examensarbetets syfte är att undersöka påståendet om att homosexuella mäns identitet inte bör representeras i tragedi, på grund av genrens maskulina ideal. Istället bör representationen ske i melodram då genren relaterar till feminina värden. Textanalysen av två teaterpjäser, tragedin The River and the Mountain (Uganda, 2012) och melodramen The Boys in the Band (USA, 1968), visar att tragedin står för en essentialistisk (biologisk) syn på sexuell identitet medan melodramen står för en konstruktivistisk (kulturell och social). Kunskap om homosexuell kultur kan inte ses som en nödvändighet för en homosexuell identitet. Tragedi bör därför inte avfärdas som en politiskt svag genre att representera homosexuella män i.
Kartläggning av spånprodukter vid Sävar såg
A change towards using more biofuels than fossil fuels is taking place in Sweden, and in many other parts of the world. This makes the use of fuel pellets increasingly popular, causing a greater demand for sawmill sawdust products. There is a trend towards the use of multiple types of shredders, instead of a single type in each sawmill. The purpose of the study was to characterize the different flows of saw particles that can be found at Sävar såg when cutting thick or thin wood with different cutting techniques. The saw particles size, shape, moisture content and heat value were analysed by the cutting stations: first cutting fast and slow, second cutting fast and slow, grading fast and slow and planning.
Bestämning av dagvattenflöden i Knivstaåns avrinningsområde
The purpose of the thesis was to map the hydraulic load on the Knivsta river from stormwater runoff, and build a platform for further studies of pollution loads on the rivers ecosystems. New residential areas are planned to be built in Knivsta municipality and it will have an impact on stormwater flows to Knivsta river. To examine the impact this will have, simulations were made in the area as it stands today and after expansion work. The work includes calculation of flows from the populated areas but also from the catchment area around it consisting of woodlands and fields. Because of expected climatic changes which may affect rainfall, the simulations have been performed with different return periods for rainfall data.
Grundvattenmodellering i Badelundaåsen
Over an extended period of time there have been plans to establish a shared facility in Lennheden to extract groundwater from the Badelunda esker to provide drinking water for the cities of Borlänge and Falun. The city of Falun is dissatisfied with the quality of its drinking water and the city of Borlänge is concerned about the risk of contamination of its existing groundwater supply at its current location. To provide a basis for a decision on this issue, the company Midvatten AB has been commissioned to perform hydrogeological investigations in the area of Lennheden.The purpose of this thesis is to design a functional groundwater model of the area between Lennheden, place of planned extraction, and Övre Tjärna, place of existing extraction, to get a better understanding of the groundwater situation in the area. A groundwater model enables simulations of different scenarios in risk assessment and contaminant transport. The aim of the thesis is that the model can be used as an aid in Midvatten?s investigations in Lennheden and that it also can be used in future projects in the area.The model has been made in Processing Modflow 5.3 and encompasses an area of 19,5 × 11 km along the Badelunda esker and the river Dalälven between Djurmo and Frostbrunnsdalen.
Assuandammens påverkan på Nilen, Egypten
Regulation of rivers by dams and reservoirs is a good example where anthropogenic impact could be considerable both in the local environment, but also has major implications upstream and downstream. This study was accomplished as a literature study of the river Nile, which is extremely important for water supply. The purpose of this study was to investigate the consequences of the construction of the Aswan High Dam, to obtain a consistent flow for water supply, irrigation and power generation in Egypt. Since Egypt has a very hot and dry climate large amounts of water in reservoir is lost to the Nubian aquifer system and by evaporation. The consequences from constructing the dam are considerable.
Re-design of Toledo Riverfront : from industrial past to sustainable biodiverse future
Effects of climate change, urbanization and global homogenization are resulted in the degradation of land and losses of natural habitats. Ecological design integrates nature into urban environment by respecting natural ecological principles and processes and creating resilient
urban biotopes which also can be used by local urban communities.
The aim of the thesis is to answer the research questions: How ecological design principles can be applied for re-design of Toledo Riverfront (with requirements of the design competition)? and What is the ecological design in landscape architecture? I participated in the USA design
competition with the aim to create a vision and redesign of Toledo Riverfront in Ohio State, USA. The site is located in the south point of Lake Erie. As a result of a long industrial activity, riverfront of Toledo had been transformed into inaccessible and abandoned brownfields.
In my proposal I applied ecological design principles on three scales:
the city of Toledo by reinforcing of ecological connection and creating green corridors along the river; the intermediate scale by suggesting public parks along the river front and on the fine level by proposing detailed design including remediation of the site and use of dredged
material.
Hur påverkas muskelaktiviteten vid styrketräning med en tjock stång i jämförelse med en standardolympisk stång? : En EMG- studie
Many everyday tasks and also many sports require good grip and forearm strength. Everything from carrying boxes and lifting a child to grab the arms and legs in various martial arts, or holding a tennis racket involving the hand and forearm muscles in various ways. It is therefore important to train these muscles to prevent injuries and congestion and to perform well in sport. A well known way to train functional strength in the hand and forearm muscles is weight training with thick handles. The purpose of this study was to investigate the differences in muscle activity in the upper arm and forearm muscles as well as the deltoids between two bars of different diameter (28mm and 57mm) in two different weight training exercises using electromyography (EMG).
Beteende hos lekvandrande lax i Klarälven ? utvärdering av en fiskfälla
During the migration season in 2013 a study on spawning migrating salmon and the effect of water flow on the behavior was conducted of the salmon at the Forshaga hydropower station in the River Klarälven. The River Klarälven with its nine hydropower plants on the Swedish side, constituting migration obstacles for the migrating salmon. Fortum Generation AB has together with the County Administrative Board restored a salmon trap at the lowermost hydropower station in Forshaga, aiming at making it possible for the salmon to swim into the trap, and thereafter be transported by truck past the power plants and then continue their journey to the spawning grounds on their own. Unfortunately, it is believed that the trap does not work as well as it should. In this study, I focused on salmon position in relation to water flow and if the number of salmon that swam into the fish trap differed between salmon with previous experience of the trap (experienced) and salmon without experience (unexperienced).
Selånger deltapark : Sundsvalls nya stadspark - en vision
The river Selångersån runs through thenorthern Swedish city of Sundsvall, splittingthe city in two as it winds through thevalley between Södra- and Norra Stadsbergetand out into the Baltic Sea.The river is a national interest of nature conservationbut at the same time in the middleof an urban development string for the city,creating a complex situation of developmentcontra conservation of natural environment.This project attempts to create a strategy oflandscape urbanism for the area surroundingSelånger Bay, four kilometers upstreamalong Selångersån. A sensitive wetland, todayrather forgotten but with great potentialfor introducing wild nature as an active partof the city. Or rather, initiating a processwhere the built environment can infiltrateand enrich the natural environment gradually.A city park in this location to initiate thisprocess could be a joint project of the city?sresidents with the scope to become a projectin constant development.The idea of the project is to offer a large ecologicalpark and meeting place near the citycenter. This will be achieved by clarifyingthe activities and values that already existin the park, such as the largest living deltai the region, football fields and a medievalchurch ruin, and by creating new paths.
Luftläckage I Småhus : Hur de upptäcks och attityderna till dem
Air tightness in new buildings has been discussed for several decades. But the knowledge in the subject is low. With tougher requirements from the Swedish government about energy consumption for a new building required competences how these shall be met. It's not only the thick mess of insulation that are important, it's also the air tightness. This report is about air leakage in Swedish houses.
Hur påverkar ålder och fetthalt laxsmoltens utvandring till havet?
AbstractPrevious studies have shown that wild smolt have 2.5-4.5 times higher survival rate than smolt grown in culture and that starved reared smolt behave more like wild born smolt. The purpose of this project was to study whether there are differences in migration patterns and survival during migration to the coast between wild and reared smolt and between different types of reared smolt.In 2009, 25 smolts in three different groups were tagged with acoustic transmitters: Wild Born, conventionally reared 2-year and 1 ?year old smolt. For the 2010 trial there was also added a group of reared 2 ?year old smolt that were starved before release.