Sök:

Sökresultat:

10810 Uppsatser om Soil treatment system - Sida 1 av 721

Soil carbon, pH and yield development in a long-term humus balance trial

Agriculture has to be performed in a sustainable way in order to sustain high yields and to support a globally growing population. Functional soil properties are fundamental for high yields and in order to achieve good soil conditions sustainable management is a key. Loss of soil organic material and increased soil acidity are problems associated with degradation of soils and hence less sustainable agriculture. In this thesis, the effect of different agricultural systems on soil organic matter, pH and yield was examined. The systems examined are a cereal system with straw removal or returning and a ley system, all with different nitrogen levels.

Långsiktig förändring av fosforhalt och skördenivåer för jordar med höga P-AL-tal : en analys av försöksserien "Exploatering av höga fosfortillstånd"

The field trial Exploatering av höga P-AL-tal (Exploiting P in heavily P dressed soils) started in 1982-1983 and included seventeen study sites placed across Sweden. Each site included three treatments, one unfertilized control (A), one aiming at replenishment of harvest removal, i.e. fertilized with 15 kg P ha-1 year-1 (B) and one over-fertilized (C) with 30 kg P ha-1 year-1. In this thesis data from the five longestrunning study sites are analysed based on four hypotheses. The hypotheses stated that in soils with high P-AL values and a pH over 6.0 P-AL will not decrease over time in the control (A) or in the replenishment treatment (B), that P-AL and P-HCl in the top soil will increase at all sites for the over-fertilized treatment (C) and that yields will not decrease as long as the P-AL is above 12 mg P 100 g-1 soil. My conclusions from the analysis of data from the selected sites are as follows: - A pH above 6.0 cannot guarantee a stable P-AL value in an unfertilized but phosphorus-rich soil. - The P-AL of unfertilized soils decreased faster at lower soil pH than at higher pH. - In the replenishment treatment (B) the rate of P-AL decrease seems to fall at a pH of 6.5. However, the influence of the soil type cannot be ignored. - P-AL and P-HCl did not increase in all over-fertilized treatments.

Where has the fertilizer gone? Closing the nutrient budget for a eucalyptus fertilization experiment in southern China

An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.

Fördjupad miljöriskbedömning av förorenade markekologiska system. : Integrering av kemisk, toxikologisk och ekologisk information.

AbstractThe research project Liberation, supported by the European Commission under the Environment and Sustainable Development Programme (Fifth RTD Framework Programme) aimed at developing a decision support system for ecological risk assessment of contaminated sites has proposed a tiered system including the triad method. This method integrates contaminant chemistry and bioavailability analyses with observed ecotoxicological effects in soil and groundwater. In this study the triad method was used to perform a risk characterization of a former surface treatment and metal industry, now used for the student union buildings of the Mälardalen University in Eskilstuna, Sweden. On the site, high concentrations of copper, zinc and nickel have been detected in the soil in a preliminary investigation of contaminant levels with XRF. For performing the risk assessment of the site according to the triad method, contaminant bioavailability, soil metal concentrations and soil toxicity were determined and an ecological assessment was carried out on four selected soil samples (one reference soil and three samples with low (B), medium (C) and high (D) contaminant levels). Contaminant bioavailability was measured through leaching (ISO TC 190/S7) and biouptake tests (DGT).

Biochar as soil amendment in flow-through planters - for increased treatment of zinc roof runoff

In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.

Vallbrott med hjälp av grisar :

To investigate the possibilities for effective soil tillage, that could imply lower costs, lower negative environmental impact and in addition a meaningful occupation for foraging pigs, a field experiment was carried out in Gränna, Småland, during growing season 2006. The experiment contained two treatments that were repeated three times and were carried out on a couch grass-infected fallow on a light soil close to Sweden?s second largest lake, Vättern. Ploughing was one treatment and pig rooting followed by ploughing, was the other. The experiment was conducted according to the guidelines of organic growing and seedbed preparation was done the same way in the two treatments. The pigs, three groups of five half-year old Linderödssvin (an old Swedish breed), was encouraged to perform an even tillage by strip-grazing, i.e.

Nutrient effects on microorganism communities in nutrient poor soils

Better, more efficient fertilizers with great productivity and economic returns are needed, but it is important today to find fertilizers that are also sustainable. It is also important to carefully monitor their impact on the environment, including potential side-effects. In this context, the microbial communities that carry out numerous essential functions contributing to a functional ecosystem are of particular interest. The present study is a complement to a pot experiment that investigated the potential of different waste products for use as fertilizers and how they affect the microbial community. In the pot experiment, the clearest treatment change in microorganism community function was found in the fully fertilized treatment used as a positive control. The question was whether this was indirect, i.e.

Ögonbehandling av häst med lavage system och infusionspump Omvårdnadsaspekter : omvårdnadsaspekter

Objective ? To study the requirement of nursing care of the equine patient during eye treatment with a lavage system together with a constant rate infusion pump. Procedures ? Three veterinary nurses at ATG: s Hästsjukhus in Skara were asked nine questions at individual interviews. Inclusion criteria for participation in the interview were that the nurse should have treated equines with and without the infusion pump to the lavage system, but also traditionally with eye drops. Results ? The equine had a higher well-being since it experienced less stress during eye treatment with the infusion pump compared to treatment given by hand through the lavage system. The treatment would be more effective with constant rate infusion and save costs for the owner.

Biologisk behandling av oljeförorenad jord : Abiotiska faktorers inverkan och effekter av olika uppläggningssätt på nedbrytningshastigheten.

The purpose of this report was to investigate how the abiotic factors (temperature, pH, nutrients, oxygen levels and water content) would affect the decomposition of oil-contaminated soil and how a variance in structured soil would affect the decomposition-rate. A minor field-study was made and soil where structured in five different ways (one was a default pile and was used as a reference). The study took place over 137 days and three samples were taken (start, middle, end) and analyzed for aromatic and aliphatic compounds. The result of this study shows that there is a significant difference between all methods for the aliphatic compounds and no significant difference for the aromatic compounds. The abiotic factors that affect decomposition vary from organism to organism, depending on what type of environment it will function the best.

Rening av lakvatten vid deponin Degermyran i Skellefteå kommun : Utvärdering av nuvarande reningseffekt och simulering av mängden bildat lakvatten under 2000-talets klimatförändringar

At Degermyran landfill, situated in the municipal Skellefteå, a leachate treatment system was installed in 2005. One of the aims of this study was to investigate how well the treatment system works by using data from chemical measurements made on the leachate before and after treatment. Further this study had the purpose of investigating how the predicted climate changes of the 21st century will affect the amount of leachate generated at Degermyran by using a modified version of Thornthwaites water balance model. The treatment system has the ability of reducing manganese by 90 %, nitrogen by 73 % och TOC by 79 %. By the turn of this century the amount of precipitation that percolates the waste at Degermyran will be between 254 and 298 mm, depending on the amount of greenhouse gases that will be released in the future to come.

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.

Termografisk undersökning med samtidig analys av rektaltemperatur, hjärtfrekvens, psykiska reaktioner och specifika blodparametrar av häst som behandlats med vibrationsboxen Vitafloor :

A number of studies in human medicine has documented positive effects of whole body vibration treatment in humans. The Vitafloor system, witch is based on treatment of horses with vibration, has the purpose to be used in training of healthy horses and as rehabilitation for horses with injuries in their musculosceletal system. The purpose of this study was to analyse what happens with a clinically healthy horse during treatment with Vitafloor. The methods used is mainly thermography before and after treatment, but also blood samples, measurement of rectal temperature, heart rate, clinical examination and observation of psychic reactions has been done. Statistic significant changes in skin temperature in hoofs and fetlocks of front legs has been observed after treatment with Vitafloor. Analyzing of the blood samples showed a tendency for decrease in Kalium, and two of the horses had changes in CK. No negative effect has been observed with the treatment of horses with Vitafloor, and the horses seems to like the treatment. .

Concentration and offtake of trace elements and macronutrients in Italian ryegrass (Lolium multiflorum Lam.) and spring barley (Hordeum vulgare L.) grown on soils amended with water treatment residual sludge

Aluminium sulphate (Al2(SO4)3) is usually added during the drinking water treatment processin order to precipitate organic and inorganic material, resulting in aluminium-based drinkingwater treatment residual sludge (WTR). Since 2003 Swedish law no longer permits WTR tobe deposited in lakes, and there is an interest to explore the possibility to utilize WTR as soilamendment. The aim of this study was to examine the effects of WTR application on cropgrowth and concentrations of macronutrients and trace elements (including micronutrients andpotential toxic elements). A greenhouse pot experiment was conducted with three soils; a clayloam rich in phosphorous (P), a loamy sand rich in P, and a silty loam with a low soil Pconcentration, and two crop species Italian ryegrass (Lolium multiflorum Lam. cv.

Effekt på mark och gröda av olika bearbetningssystem, med och utan CTF

Swedish agriculture has gone through big changes in the latest 60 years. The farm sizes have increased, which has led to raised tractor and machinery sizes and therefore increasing problems with soil compaction. A method to reduce these problems is to implement controlled traffic farming, CTF. All field operations are then concentrated to specific tracks by using GPS guidance. The aim of this work was to study how the tillage regime, with or without CTF, affects the soil, with the main focus on macroporosity. In Säby close to Uppsala, and Alnarp close to Malmö, randomized block trials has been carried out, and the data has mainly been taken from these trials.

Sönderdelning av plogtilta med skärknivar :

During the last couple of years it has been more important to reduce the driving on the field to prepair the soil after ploughing. The machine costs are high so it is necessary to be effective. To reach a pleasant soilbed directly after ploughing is sometimes possible on easier soils but heavier clay soils always need more tillages. There is a lot of equipment mounted on the ploughs on the market, for example Furrow Cracker and Furrow presses, which makes a pleasant soilbed on easier soils. The last year Överum and Kverneland have presented knives which are mounted on the wing or moulboard.

1 Nästa sida ->