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323 Uppsatser om Nitrogen removal - Sida 6 av 22

Möjligheter att förutsäga kvävegödslingsbehov i höstvete med Yara N-tester

The Yara N-Tester is a handheld chlorophyll meter which can be used in several different crops as an aid to determine if there is a need of complementary fertilization with nitrogen (N) or not. If the crop requires more N the N-Tester will recommend an amount in kg per ha. The possibility to assess the need of N depends on the strong relation that exists between chlorophyll- and N-concentration in the leaves of plants. In the multiannual trial series ?Nitrogen to winter wheat at different soil conditions? measurements with the N-Tester was carried out at flag leaf emergence (GS 37). In this work the result of measurements, the NTesters ability to estimate the need of N in winter wheat, will be presented for the years 2008-2011.

Biomassauttag vid delkvistat sortiment i klen gallring

The purpose of this study was to estimate the removal of biomass in connection with thinning operations in young stands that are dominated by small diameter trees. The economy of such operations depends on the products generated as well as the performance of the harvesting systems. Conversion tables designed to predict the outcome based on harvesting method was another goal of this study. Removal of biomass affects the nutrient composition of the site. Therefore it is a purpose that this study will provide researchers with some variables that can be utilized when studying this aspect. Trees were harvested and divided into bunches based on diameter.

Vad orsakar höga ammoniumvärden i ensilage? :

High levels of ammonia in grass silage have been up for discussion by Swedish advisers. One reason is that it is more difficult for the rumen-microbes to utilise high levels of ammonia. A low level of ammonia is also good because if the cattle can use more of the protein in the silage, they don?t need so much protein concentrate. That is very good for the economy at the farm, and it is also good for the environmental problems caused by high levels of ammonia. In this project, 24 samples of silage have been taken at 20 different farms in the south west of Sweden.

Translokation av större vattensalamander : -bevarandestrategi eller riskåtgärd?

This study evaluates the retention of nitrogen and phosphorus in four newly constructed wetlands in the municipality of Falkenberg, Sweden. The four wetlands have been selected because they have been specifically constructed with the aim to reduce nitrogen and phosphorus in farming areas. The process of selecting the specific wetlands has been done in collaboration with the county administration in Halland. Through field studies in collaboration with the landowners where the wetlands are sited, the areas that provide the wetlands with water were determined. The size of these drainage areas were determined in a GIS computer program. The type of land use within the drainage areas was also determined.

Proveniensbestämning av vikingatida hornmaterial : En studie utifrån stabila isotoper

The main aim was to investigate the provenance of Viking age antler material findings of moose and red deer from Sigtuna and from three sites on the island of Gotland in the Baltic sea. This was done by analysis of the stable isotopes of carbon, nitrogen and sulphur. Thre were never any living population of these mammals on Gotland during the Viking age.?34S-values of sulphur from this study was compared with earlier research and by studying maps of the Swedish bedrock. The ?34S-values were more like the ?34S-value for bedrock other than European granite.

C?RONIS BIVAXFERNISSA En unders?kning av inneh?ll, l?slighet och ?ldringsegenskaper

The aim of this study is to provide a comprehensive overview of C?ronis beeswax varnish by Lefranc & Bourgeois; its contents, aging properties, solubility, and possible removal methods, with G?teborgs Konstmuseum?s ?Gothenburg Museum of Art? collection as the stud??s material? The purpose of the study is to provide a basis for decision-making regarding the treatment of works treated with C?ronis wax varnish. The study is based on contemporary conservation theory and interpretation-based decision-making and utilizes FTIR, microscopy, and solubility tests to examine the properties of the varnish. The study shows that C?ronis does not appear to be harmful to the treated works and has retained its solubility properties and transparency over time.

Näringsämnesretention i fyra nyanlagda våtmarker i Falkenbergs Kommun

This study evaluates the retention of nitrogen and phosphorus in four newly constructed wetlands in the municipality of Falkenberg, Sweden. The four wetlands have been selected because they have been specifically constructed with the aim to reduce nitrogen and phosphorus in farming areas. The process of selecting the specific wetlands has been done in collaboration with the county administration in Halland. Through field studies in collaboration with the landowners where the wetlands are sited, the areas that provide the wetlands with water were determined. The size of these drainage areas were determined in a GIS computer program. The type of land use within the drainage areas was also determined.

Näringsretention i återskapad våtmark på betesmark : studier av en mad vid Bornsjön

It is important to construct or recreate different types of wetlands and study their retention of nutrients, since knowledge of their effectiveness in this matter is poor. In 2003 a wetland was constructed on an old meadow on the western shore of Lake Bornsjön in central Sweden. The main purpose of the wetland was to reduce the amount of phosphorus entering the lake, which is the back-up water supply for Stockholm when the city cannot obtain water from Lake Mälaren. Large areas around Lake Bornsjön consist of agricultural land and the nutrient concentrations in the inflows to the lake are usually relatively high (approx. 1 mg/l total nitrogen and 0.05-0.1 mg/l total phosphorus).

Kvickrotsstudier: 1. Kvickrotens reaktion på myllningsdjup, kvävemängd och kväveplacering i konkurrens med gröda. 2. Reducerad glyfosatanvändning på trädad åkermark :

1. Reaction on burial depth and nitrogen availability and placement in competition with a crop In this trial it was investigated how couch grass (Elymus repens) changes its ability to compete in stands of wheat and barley with different burial depth and different amounts and placement of nitrogen. More knowledge in this area can be valuable in the attempt to decrease the use of herbicides and still keep the weeds under control. The trial was carried out in the summer of 2004 as an outdoor pot experiment. The pots contained 15 litres of soil with a surface of 0,06 m2.

Miljöpåverkan av äggproduktion : En jämförelse mellan Lilluns ägg och andra svenska äggproducenter

The purpose of this report was to compare Lilluns egg production with other Swedish egg producers based on the flow of nutrients (nitrogen, phosphorus and potassium) in the egg production systems. The main focus in the report was the utilization rate of the forage and the excess of nutrients per kg egg. Additionally, the purpose was to identify the environmental impact from Lilluns egg production and compare the results with other egg producers. The inflow of nutrients associated with forage and poultry was compared with the nutrients that were exported from the production. All of the egg producers in this study had an excess of nutrients.

Foderbetor och kogödsel som substrat för biogasproduktion; anaerob mesofil samrötning i labbskala

One of Sweden?s sixteen national environmental objectives strives to decrease the impact on the climate. By 2020, green house gas emissions should be 40 % less compared to the levels of 1990 and a minimum of 50 % of the energy consumption should come from renewable energy sources. Because of this there is a great need of increasing the production of renewable energy. This is where biogas comes in as a competitive alternative.

Batch flow behandling och kontinuerligt flöde av lakvatten i en rotzonsanläggning : En jämförande studie i pilotskala

This report deals with the performance of a batch flow treatment of landfillleachate compared with a continuous flow system. The parameters in focus were total Kjeldahl nitrogen (TKN), BOD5 and COD. The pilot-scale experiment used eight barrels with a volume of 150 liters. Each barrel was constructed differently concerning its flow, its bed material grain size and its presence of plants or not. Four of the barrels worked in batch mode, thus four in continuous flow mode.

Effekter av kalavverkning på mindre boreala sjöars vattenkvalitet

Forestry is an important industry in Sweden, with clear-cut as the most commonly used method for harvesting. Here the long-term impact of clear-cut on lake water quality (dissolved organic carbon (DOC), nitrogen, phosphorus and pH) has been investigated, based on 23 lakes sampled during autumn. Data for additional 15 lakes sampled for the Swedish monitoring program were also used. Lakes were classified as 5, 25, 40 and 60 year based on data of the forest age in the catchment, gathered from the Swedish national forest inventory. Clear-cut lakes were classified as 5 years (>20% of the catchment clear-cut during the last 10 years).

Lyviken : -bedömning av dagvattenkvalitet

AbstractStormwater is defined as rain- and melted water. Ludvika kommun had little knowledgde about the stormwater that reaches a specific recipient Lyviken. Therefore they intended to do an research of the stormwater that leads down to Lyviken. The aim with this study was to assess the quality of the contents in the stormwater based on pH, conductivity, phosphorous, nitrogen, bacterias, oil and one sample that meassured the value of several methals. Since the population has increased for decades, the area of hard surfaces and asphalts areas also has increased. This can increase the pollutions that finally ends up in the recipient.

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.

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