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4047 Uppsatser om Soil water content - Sida 32 av 270
Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige
Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.
Kan en lockande och informativ webbplats marknadsföra ett bibliotek? Tankar om webbplatsens roll i stadsbiblioteks marknadsföring
The web sites of libraries are to a large extent their public face and to help market their services, the web sites must have interesting and regularly renewed content. They must also be visually attractive and easily used, and thus be well structured and have a well functioning navigational system. The web masters' awareness of the ability of web sites to attract users to the site and also to the library, as well as their knowledge of suitable content and site construction, is crucial for how successful the web site actually is at marketing the library. The research question is: How do the studied web sites function as marketing sources and service providers for the libraries, and are the web masters aware of the importance of the web site? The purpose is to investigate how the library personnel looks upon the web site as a possible way to increase the popularity of the library among the public, and to study the construction and content of the library web sites to find out how well these serve their purpose.
Rening av avloppsvatten med anaerob membranbioreaktor och omvänd osmos
This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a reverse osmosis unit and a total of four batch runs have been made with good results. The use of reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.
Spillvärmeåtervinning ur kylvattensystemet ismältverket på Sapa Profiler AB i Sjunnen
The smelting process at Sapa Profiler AB in Sjunnen generates large quantities of waste heat which is absorbed by the cooling water when the aluminum is cooled down. This paper is the result of a Master?s Degree Project aiming to present the conditions for recycling the waste heat. The cooling water absorbs the heat from the aluminum at an average rate of 600 kW and the paper shows that it can be used to replace electrical power consumption for heating the production plant?s facilities.
Ökad kollagring i boreal skog : Kan blädningsbrukad skog lagra mer kol än trakthyggesbrukad skog?
This study was conducted to test the hypotheses that a forest managed by selective cutting can store more carbon than a forest managed by clearcutting. The study was carried out as a meta-analysis. The data that was found was analyzed by performing t-tests on the proportional effect that the two silvicultural methods had on the driving factors of CO2-efflux and carbon stores in coniferous boreal forest. In all areas tested, an effect in favor of selective cutting was found, but not all of them significant however. The soil respiration following selective cutting was significantly lower than that of clearcutting, and the primary production of a clearcut area cannot according to reason exceed that of an area post-selective cutting.
Skogsbränslets fraktionsfördelning
This study has analyzed particel size distribution and needle content in chipped logging residuals (branches and tops) delivered to the district heating plant Ryaverket in city of Borås, Sweden. Two fuel assortments has been analyzed: Chipped logging residuals from pure softwood and from mixed fuel (connifers and broadleaves). The samples has been sieved at Linneaus University laboratory.The study of particle sizes indicates that only 53,2 % of delivered fuel is within the fuels specification (7? 45 mm). The needle content is in this study 12,4 % (dry mass) which is higher than expected..
Nursing technique and growth environment of Rabbit fish (Siganus guttatus) in the area of Tam Giang lagoon, Thua Thien Hue
SummaryIn the area to the east of Hue city, in Vietnam, lays Tam Giang lagoon, one of Asia's largest lagoons, with an area of 22,000 hectares. This lagoon is suitable for aquaculture. One reason for this is because the salinity differs from sweet to salty in different parts of the lagoon. The Vietnamese Government advocates an increase in environmentally-friendly aquaculture and the fish Siganus guttatus (Rabbit fish) is a candidate for this. This fish eats mainly algae and can be cultivated in a polyculture.
Årstidsdynamik för kvicksilver i ett sövattensediment :
The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment.
The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake.
Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.
Riksdagspartierna på Facebook : En kvantitativ innehållsanalys av interaktivitet och multimodalitet i riksdagspartiernas statusuppdateringar
This study focuses on the social medium Facebook. Its intention is to examine the contents of the Facebook statuses the Swedish parliament parties chose to publish in the final two weeks before the parliamentary elections in 2010. The key concepts used in the analysis are interactivity and multimodality. Aspects to be explored are interactivity of their status updates and how the parties used various multimodal objects. A comparison of the parties' usage also follows.
Varför sviktar elevers intresse för matematiki de högre åldrarna? : Vilka faktorer ger elever motivationoch lust att lära matematik?
Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.
Naturlig förekomst av arsenik och avskiljning av arsenik från grundvatten : test av olika filtertekniker avsedda för enskilda brunnar
During the last few years the presence of high arsenic (As) concentrations in ground water has been of major concern both internationally and in Sweden. Much evidence has been reported about toxic effects caused by arsenic. The carcinogenic effects and the possibility to measure the toxic impacts at low concentrations made the World Health Organisation (WHO) to reduce the guideline value from 50 to 10 ?g l-1 in 1993. In Sweden the corresponding reduction was implemented in 2003.
Several surveys in Sweden have shown that high arsenic concentrations may occur in ground water.
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.
Design Program for Dessie Campus, Wollo University, Ethiopia
A geographical position and its social, cultural and political context as well as climate
and specific physical characteristics define the scope for a landscape design project.
This has become clearer for us in our master project where we have made a Design
Program for the outdoor environment of Wollo University in Dessie, Ethiopia and
analysed and reflected on the work and process. The aim for the project has been
to design an attractive and functional outdoor environment for the Campus, based
on the inventories and the needs and wishes of clients and users. But, the aim has
also been for us as landscape architect students to gain a greater knowledge about
landscape architecture and the design process by position ourselves outside our usual
context. The method has been open and seeking where the site, literature studies,
dialogues with people and our own experiences from the field study in Ethiopia has
influenced the work.
Wollo University is situated 400 kilometers north of Addis Ababa, in a
mountainous landscape. It faces problems of heavy rainfall during the summer,
soil erosion, a lack of essential facilities, and is still a construction site with empty
spaces in-between buildings and infrastructure.
Kvalitetsarbete i grotskotning
This study was carried out at the request of the Swedish forest company Sveaskog which is an important producer of logging residues (branches and tops) intended for energy production. The company wanted to increase the average dry content to 60 percent in their delivered logging residues. At the time when this study was initiated, the dry content in the chipped logging residues originating from the Bergslagen district was at 52 percent. The aim of the study was to find out how windrows of logging residues could be arranged in order to help obtain desired properties such as increased dry content. Sveaskog had developed a system for evaluation of windrows and a standardized form was utilized to describe different properties of the windrows.
Jämförelse mellan våtkompostering och andra VA-system i omvandlingsområden : en fallstudie i Norrtälje kommun.
Eutrophication of the Baltic Sea and Swedish lakes remains a major problem despite many years of effort to reduce the emissions of nutrients. One major source is waste water systems, especially private sewage systems. These sewages accounts for a very large share of nutrients per capita in comparison with citizens connected to larger sewage treatment plants. Norrtälje community has the greatest number of private sewage systems in Sweden. Discharges of nutrients, especially phosphorus, to the Baltic Sea from these sewage systems are significant.