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7220 Uppsatser om Nitrogen management - Sida 4 av 482

KVÄVEUPPTAG HOS FÅNGGRÖDORNA VITSENAP OCH OLJERÄTTIKA VID OLIKA ETABLERINGSMETODER :

The object with this thesis is to evaluate which of the catch crops oil radish and white mustard in combination with establishment method, give the most effective nitrogen uptake. The main purpose of the catch crops is to reduce leakage of nitrogen. They are sown after the main crop and killed before the next crop. In Sweden the farmers gets subsidies to establish catch crops. The thesis is limited to the trail L3-9010 sited at HS- Malmöhus, Borgeby Gård, 237 91 Bjärred, Sweden, 2007. Only treatments with oil radish, white mustard and the reference treatments were studied.

Övergödning i Laholmsbukten  En studie av Laholmsbuktens övergödningssituation

This essay discusses the Laholm?s bay and its eutrofication problems. The question of issue is: Have the efforts to limit the eutrofication in the Laholm?s bay been effective? What is the local actor?s opinion whether the measures have been effective or not? What efforts have been made to prevent the leakage of nutrients from fields and forestland? The Laholm's bay is located in the south part of the Swedish west coast. The problem was noticed in the 1960´s by local fishermen that experienced a lack of catch.

Jordbrukets påverkan på Östersjön : en jämförelse av indikatorer för att beskriva näringsbelastningen

The Baltic Sea, due to its special conditions, is a unique and vulnerable marine environment. There are many pressures that have an impact on the sea and one of the major problems is the extensive flow of nutrients from land. The most visible effect of the supply of nutrients is the annual algal blooms. One of the main sources of nitrogen and phosphorus supply is agriculture. Nutrient losses from arable land have been increasing as agricultural production has intensified. At the end of the twentieth century an increased awareness of these problems led to the formation of organizations such as HELCOM and Baltic 21.

Evaluation and Comparison of Ecological Models Simulating Nitrogen Processes in Treatment Wetlands,Implemented in Modelica

Two ecological models of nitrogen processes in treatment wetlands have been evaluated and compared. These models have been implemented, simulated, and visualized in the Modelica language. The differences and similarities between the Modelica modeling environment used in this thesis and other environments or tools for ecological modeling have been evaluated. The modeling tools evaluated are PowerSim, Simile, Stella, the MathModelica Model Editor, and WEST. The evaluation and the analysis have been performed using McCall?s factors for software quality (McCall et al, 1977), a correlation analysis and the Constant Comparative Method (Glaser&Strauss, 1999).

Referensvåtmarker för uppföljning av växtnäringsretention i anlagda våtmarker

One of the environmental problems today in seas, lakes and streams is eutrophication. This is often caused by nutrients such as phosphorus (P) and nitrogen (N) that leak from agricultural areas. A measure to partly prevent the nutrient discharge is to construct or restore wetlands.In order to control the efficiency of nutrient reduction of existing wetlands in the county, the administrative board in Västra Götaland wants to find different criterias for reference wetlands. These reference wetlands should represent other wetlands and be used in future evaluations of reduction of nutrients and design of constructed wetlands. According to the administrative board in Västra Götaland the reference wetlands should have a catchment area of about 50 hectare consisting of at least 70 % arable land, to represent wetlands created to remove nutrients.

Kvävemineralisering från stallgödsel beroende på olika grad av inblandning i mark

The impact of the distribution in the soil volume of two farm manures on the net mineralization and immobilization processes of nitrogen were studied in an incubation experiment. Cattle slurry and broiler litter were placed in the soil with three procedures for incorporation including placement on top of the soil (TOP), in the middle of the soil (MID) and mixed homogenously with the soil (MIX). During the two weeks of incubation, few significant differences in net mineralization were seen between TOP, MID and MIX. However, there was a tendency that MIX led to a larger net immobilization of N than placement at one point (TOP and MID). This is also the result in the literature.

En studie i Culture management

Culture Management Cultural management administration producent KKE management.

Utvärdering av Vissberga lakvattenbehandling

In connection with the admittance of the EC-directive (99/31/EC) in Swedish politic, through the constitution of waste depositing (2001:512) at year 2001, the rules about management the landfills and leachates tightened. At the landfill Vissberga in the municipality of Hallsberg, a leachate treatment plant was constructed just a year thereafter. This treatment plant consisted of an aerated pond with a following land treatment and a willow cultivation to replace the land treatment during the summer. In this case the parameters, which were estimated as the most important to reduce, were iron and nitrogen. The iron would react with the oxygen-rich water in the aerated pond and precipitate to ferric-hydroxide and than settle in a calm zone of the pond.

Synoptisk provtagning i vattendrag med eutrofieringsproblem : En studie för att identifiera områden för prioritering av åtgärder

In Halland, agriculture is the major source of eutrophication of water. In the study, synoptic sampling were performed in the three watercourses Nyrebäcken, Skintan and Vinån all located in the county of Halland. Sampling occurred during the period February to May on three occasions with different flow rates: high, low and base flow. Samples were taken in the mainstream and tributaries with intention to show how big the impact of eutrophication it is in the water and  to assess the impact of the tributariesThe results show that all watercourses are affected by eutrophication. Nyrebäcken has the highest concentrations of nitrogen and phosphorus in the mainstream, then Skintan and last Vinån.

Övergödning av Mälaren : Betydelsen av antalet beviljade dispenser av stallgödselspridning vid Sagån

Eutrophication was recognized in the early 1900's and results in severe algal blooms, increased biomass production and eventually leads to an altered ecosystem. In Mälardalen we find the most eutrophic lakes. Most of the applied phosphorus and nitrogen into seas and oceans comes from agriculture, and the nutrients losses are affected by local weather conditions and soil type. Guidelines for storage and distribution of manure were introduced in the 80s, and the rules were strengthened January 1, 2010. Localities and previous county administrations can whether there are special reasons, grant an exemption for manure application during winter-periods despite the current ban.In this essay I have examined how many exemptions of manure application that has been granted at the Sagån river, and what implications it has for the eutrophication of Lake Mälaren.

Optimering av SNCR-system i en biobränsleeldad panna : möjligheter till minskade NOx-utsläpp för ENA Energi

Emission of nitrogen oxides as well as carbon monoxides is an inevitable result of combustion. A Swedish law "Law of environmental fee for emissions of nitrogen oxides as a result of energy production" (lagen om miljöavgift på utsläpp av kväveoxider vid energiproduktion (SFS 1990:613)) controls the emission of NOx from energy production by a system of fees. The system has resulted in a strong approach toward less emissions of NOx among the energy production plants. High emission levels, today exceeding 52 mg/MJsupplied fuel, leads to costs for energy production companies. This paper examines possibilities to reduce the emissions of NOx by optimization of the SNCR-technique in a biofuel fired heat and power plant.

Närsaltsdosering till luftad damm : en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm

In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen.The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction.One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime.

Kvickrotens reaktion på klippning och konkurrens i rajgräs- och vitklöverbestånd :

Couch grass (Elymus repens (L.) Gould) is a severe weed in Sweden, and since both the use of herbicides and cultivation should be decreased, it will become increasingly problematic to control couch. The present work is meant to, by literature studies and an experiment, give some answers to the question if cutting and competition can depress the growth of couch. The experiment was carried out in the growing season 2001 at Ultuna, Uppsala, in plastic boxes. The design was three-factorial randomised complete blocks. The factors were plant combination, nitrogen level and cutting strategy.

Revenue Management - Mycket mer än bara intäktsoptimering!

Denna kandidatuppsats syftar till att undersöka hur hotellverksamheter praktiserar Revenue Management, genom att behandla interna och externa influenser..

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.

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