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221 Uppsatser om Nitrogen fixation - Sida 3 av 15

Långtidsuppföljning och artrosutveckling hos hundar kirurgiskt behandlade för ruptur av kraniala korsbandet :

The high incidence of cranial cruciate ligament injury in dogs results in both suffering and significant costs due to treatment and care of affected dogs. Today there are several different technics for surgical treatment in dogs with ruptured cranial cruciate ligament. At University Animal Hospital (UDS), SLU, in Uppsala two fundamentally different methods; TPLO (Tibial Plateau Leveling Osteotomy) and external fixation with suture material are practiced. The aim of this study was to estimate if the different surgery technics result in any difference regarding the function of the dog in a long term perspective. Since motion and function are very affected by arthritis, was the purpose also to determine if there are any differences in developing arthritis between dogs surgical treated with external fixation respectively with TPLO. Development of arthritis is common after surgery or traumatic injuries in a joint, such as cruciate ligament rupture. Unfortunately was the number of dogs in the study to small to achieve two comparable groups.

Metodundersökning av tre metoder för kvävemätning i en arktisk äng : Jämförelse mellan mätmetoderna extraktion, inkubation och jonbytesmembran (PRS-sond)

The purpose with this report was to compare three commonly occurring methods for measuring plant available nitrogen in soils. The methods extraction, incubation and Plant root simulator (PRS) probe - an ion exchange membrane (Western Ag Innovations, Inc., Saskatoon, Canada) method were used and comparison between these methods were conducted. A full factorial experiment were set up in northern Finland with the treatments excluding herbivores, warming and fertilization to see how the inorganic nitrogen content in the soil was effected by the treatments. Soil cores were taken and from them a subsample was incubated for 18 days and thereafter analyzed for inorganic N in laboratory. PRS- probes were in the ground for 1 month.

Olika typer av täckning och samodling och dess påverkan på antalet skadegörare i en Pak choi odling :

The purpose of this report is to examine the possibilities to decrease the number of insects and other pathogens in a crop of pak choi (Brassica rapa), grown with different types of cover and living mulches. Included in the report is a study of literature where amongst others, a summary on the vegetable pak choi and theories of living mulches and different kind of covers are to be found. To examine the amount of predators in the field, traps were used. During the autumn 2002 the tests were conducted in Alnarp. The pak choi and the living mulches were planted/sawn at the same time, the different covers were also applied at this time. The total experiment was divided into six different treatments (plus control) of which three were with covers and three were with living mulches. Once a week the number of leaves, the height and damages were read on ten of the plants from each parcel.

Indirekta effekter på marklavars abundans och diversitet vid ökad kvävehalt i marken : en jämförelse mellan opåverkad och lågintensivt brukad mark

Lichens are adapted to bright and sparse forests on oligotrophic ground. Due to a slow growth rate and high light demand lichens will suffer from competition in eutrophic environments. Therefore, lichens have disappeared from managed forests where the forest industry has increased the productivity. A reduced abundance of lichens will affect both biodiversity of the forest and the reindeer winter graze lands. It is important to understand how and for how long fertilization affects the abundance and diversity of lichens in order to protect lichen rich ecosystems. We have registered the biomass and number of lichen species in eight plots (four nitrogen rich and four nitrogen deficient) and compared fertilized Sami settlements with their oligotrophic surroundings in the nature reserves of Tjeggelvas.

Rimbo våtmark : en förstudie på förväntad kväveavskiljning och lämplig växtlighet

This study was made as a part of a feasibility study on a polishing wetland at Rimbo wastewater plant (wwp) in Norrtälje municipality. The wwp had to decrease the nitrogen discharge to reach the limit 15 mg tot-N/l. The nitrogen in the outlet was mainly in the form of nitrate, hence the wetland mainly ought to support denitrification. The proposed area for the wetland was situated right next to the wwp and was already in the municipalitys posession. One aim of this study was to examine what spieces of plants needed to achieve highest possible denitrification.

Nutrient efficiency in Swedish dairy cows fed total mixed rations or partial mixed rations

The relatively poor economy in European dairy farming might be improved from efficient feeding systems and dietary management. Increasing herd sizes and transition to loose housing systems in Sweden, increases the possibilities for other feeding systems than separate feeding that is the traditional feeding system in Sweden. Other possible feeding systems are partial mixed ration (PMR) and total mixed ration (TMR), where the TMR system sometimes is associated with overfeeding and thereby increased environmental impact and high feed cost. Diets providing nutrients above or below animal requirements are considered as unbalanced, which in turn are associated with reductions in health, fertility and milk production. On the other hand, a balanced feed ration improves feed efficiency, nitrogen utilization and profitability.

Rondellen och dess växtmaterial

Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board.

Nedfästning av oljemåleri på puts.En fallstudie från salongen på Mostorps slott i Halland

This thesis, designed as a case study, is about complications concerning conservation of a decorative oil paint on lime plaster from the drawing-room in Mostorp castle sited in the county of Halland in south-west of Sweden. The building was built 1878-80 with an exterior of granite. The interior walls were made of clay bricks, lime mortar and lime plaster. The oil paint is applied to a layer of putty. The combination of different materials, which are organic and inorganic, affects the movement caused by internal and external stress.

Kväveförluster och energianvändning på mjölkgårdar i västra Sverige :

Protecting the environment has with time grown to take a more central role in the society. Agriculture plays an important role in the society since this sector produces our food. More thorough research on how agriculture affects the environment is therefore motivated. This research can be used to improve the agricultural practice from an environmental point of view. This is something that both the farmers and the consumers can profit from. This study aims to form the basis for creating environmental indicators for use of nitrogen and energy on dairy farms. Twenty-three farmers in western Sweden have been interviewed about their farms, both organic and conventional. They produce milk with different intensity, defined as the amount of milk delivered (sold) per hectare of arable land.

Fordonsgas ur gödsel och vall

AbstractThe dependency of fossil fuels in the transport sector causes large emissions of carbondioxide. This problem can we reduce by using vehicle gas from digested solid manure and leftover of pasture. I have studied the potential for this in the county of Västernorrland. Thepurpose is to investigate how much vehicle gas that can be extracted.One central, large scale digestion and upgrade plant should be placed in Härnösand. Theamount of pasture and manure that is economical and practical available is enough to produce2,7-3,5 millions Nm3 vehicle gas.

Optimering av indunstningsprocess

The wastewater treatment plant at GE Healthcare's facility in Uppsala deployed a three step vacuum evaporator in 2007. The purpose of this was to pre-treat wastewater containing amines. The purpose of this thesis was to optimize thisprocess by reducing the amount of concentrate without releasing more nitrogen tothe environment and to examine if density could be used as a measurement of whenthe process should be ended.To create a foundation for optimization six test cycles were conducted with samples taken from all three steps. Both concentrate and condensate were tested as well as the incoming solution. Furthermore, the thesis has been expanded with a benchmarking part examining two different evaporators.

Vårvetesorters effektivitet i användningen av kväve under den huvudsakliga tillväxtperioden

Crop efficiency in utilizing available nutrients is an important factor in increasing produc-tivity and reducing the environmental impact of agriculture. Nitrogen is the nutrient that plants need in the largest quantity and wheat, along with maize and rice, is the world's most cultivated crop. In this work, the Nitrogen Use Efficiency, NUE, during the major growth period, HTP, of twelve different spring wheat varieties, were examined. The NUE was calculated as the product of uptake efficiency of nitrogen, UN, and the conversion effi-ciency of nitrogen to biomass, EN. The purpose of this work was to find if there are varietal differences in NUE and its components among the twelve varieties and to link a high NUE to specific characteristics of the varieties.

Miljödammars funktion som kväve- och fosforfälla samt som bevattningsdamm i Sölvesborgs kommun

A study was made on four environmental ponds in Sölvesborgs municipality. The reason forthis was to see if the ponds had fulfilled some of the questions that was mentioned in theproject ?Rädda Hanöbukten?. The questions were as following; do the environmental pondsdecrease the leakage of nitrogen and phosphorus into Hanöbukten, do the ponds decrease theuse of groundwater in Sölvesborgs Municipality and are there any restrictions on what thewater in the ponds is allowed to be used for. In order to answer these questions aquestionnaire was made and interviews were held.

Reduktion av föroreningar i processvatten från en äggfabrik i Brasilien : Kväve- och fosforrening i anlagda våtmarker.

A water treatment unit consisting of two aeration basins, two settling tanks, a residence basinand a horizontal subsurface flow wetland were used to treat wastewater from an eggprocessing factory in Brazil. The aim of this paper was to determine the efficiency of thesystem in reducing nitrogen, phosphorus, BOD5 and TSS (among other parameters) andgetting a further understanding on different kinds of constructed treatment wetlands as well astheir nitrogen and phosphorus removal processes. The wastewater from the factory consistedof process water from manufacturing and water used for cleaning, no stormwater or sewagewater entered the system. Tests were taken three times a month from October 2013 ?til April2014.

Finns det något samband mellan stormusslors (unionoida) föryngring och utsläpp i närheten av dess levnadsmiljö? : en jämförelse mellan vattendrag i Västra Götaland

Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board.

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