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352 Uppsatser om Organic hydroponic - Sida 11 av 24

Bottensedimentets betydelse för flodpärlmusslans föryngring ? en metodutveckling

The freshwater pearl mussel Margaritifera margaritifera is an endangered species. To survive, the young mussels demand a fairly coarse bottom material containing an appropriate quantity of organic substrate to survive without suffocating. In order to estimate if a bottom is suitable for juvenile mussels, samples of the sediment are needed. To obtain samples a sampling device called the Mulv collector has been developed within this project. Bottom samples were collected from 18 stations in 4 south Swedish streams, Vramsån, Kling-storpsbäcken, Brönnestadsån and Bräkneån.

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.

Problem med röda hamburgare efter tillagning : bakgrund och möjliga lösningar

Persistent pink in beef patties and hamburgers is a problem in the meat industry that has been known for a few decades. It is a costly problem as it can give rejections of food by consumers. Studies around the world have tried to solve the problem but it still remains a mystery. There are many different theories of what is causing the red colour. Some of the most likly theories are reducing hemocromes, high microbiological loads, contamination of nitrite or organic/non organic substanses, DFD meat etc.

Carbon sequestration in the pastoral area of Chepareria, western Kenya : a comparison between open-grazing, fenced pastures and maize cultivations

Carbon sequestration through restoration of degraded pastoral soils is an advocated way of mitigating global warming, and simultaneously alleviating poverty. An often proposed rehabilitation strategy is fencing of pastures, a method that was introduced to the farmers of Chepareria by the Vi-Agroforestry organization in 1987. The landscape of Chepareria changed from eroded, over-grazed grasslands, to a mixture of open-grazed commons, pastoral enclosures and cultivations. The aim of this study was to investigate (1) if the soil organic carbon (SOC) is higher inside the enclosures than on the open-grazed commons, (2) if SOC is affected by duration of fencing and (3) what effect cultivation of pastures has on the SOC. Estimations of vegetation cover and deep profile (100cm) soil sampling was performed on six clusters containing; (1) open-grazing (OG) (2) 1-5 years of fencing (FENCED(1)), (3) 7-10 years of fencing (FENCED(2)), (4) 15-23 years of fencing (FENCED(3)), (5) maize from OG (A(OG)), (6) maize from fenced pasture (A(FENCED)).

Nationellt miljökvalitetsmål på lokal nivå : en fallstudie av arbetet med miljökvalitetsmålet Ett rikt odlingslandskap i Lunds kommun

Several thousand years of human impact on the landscape in the form of cultivation is the reason to many nature- and culture values in the agricultural landscape today. Intensification and rationalization has led to vast monocultures and has forced many farms to close down. These trends have increased in the last years and constitute great threats to the values of the cultivation landscape. The purpose with the environmental objective A varied agricultural landscape is to protect these values. The environmental action plan of the municipality of Lund (LundaEko) 2006-2012 is built on the 16 national environmental objectives. The purpose with this paper is to put together material that the municipality of Lund can use in their work with modifying the local intermediate goals for the environmental objective A varied cultural landscape. The overall issue for this paper is ?What has happened with the state of the cultivation landscape in the municipality of Lund since LundaEko was approved in 2006?? The paper seeks to portrait the current conditions of the following fields: meadows and pastures, organic farming, exploitation threats to agricultural land, landscape elements with cultural values and species that are threatened.

The effect of arginine on root system development in Norway spruce (Picea abies L. Karst) somatic embryos

The demands for higher production yields and better quality materials from the forests are increasing globally. Tree breeding programs are directed to meet the future demands on forests. In order to capture the full benefits from the breeding programs, clonal propagation is necessary. For most conifer species, somatic embryogenesis (SE) is the only available option for large scale clonal propagation of Elite clonal material. For Norway spruce (Picea abies L.

Magnesiumstatus hos mjölkkor : en fältstudie

Magnesium is an essential mineral that is important for several physiologic and biochemical processes in the body. Deficiency of magnesium is mainly associated with grass tetany, but can also appear in cows during the indoor period. Since long it is known that potassium has a negative effect on the absorption of magnesium. Due to the fact that potassium fertilisation leads to a higher potassium content in forage, it is of interest to study interactions of potassium on the magnesium balance in dairy cows. There are few studies about magnesium feeding to dairy cows in Sweden and the purpose of this study was to investigate how much magnesium and from which feed-sources dairy cows in Sweden get their magnesium. Data was collected from seven farms in the northern part of Uppland and from seven farms in Skaraborg in Sweden.

Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project

The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations. The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.

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.

Mineraliska material som reaktiva filter för avskiljning av tungmetaller från dagvatten

Highly polluted urban storm water from e.g. highways can contain large amounts of heavy metals that may cause harm if they are discharged into recipients. To remove the heavy metals a possible low-cost method that does not require much maintenance, could be the use of reactive filters with filter materials consisting of industrial residues or other cheap mineral based materials. Dissolved metal ions are removed by reactive filters through the processes of ions binding to active sites on the surface of the filter materials, or by formation of insoluble precipitates.The ability of CaO-treated granulated blast-furnace slag, iron oxide coated sand, olivine and nepheline to remove seven heavy metals (Cr, Cd, Cu, Ni, Zn, Pb and Hg) from urban storm water was studied. Initially batch experiments were performed where the effect of pH, dissolved organic carbon (DOC) and dissolved ions on the adsorption efficiency was studied.

Energianalys av hygieniseringssystem : jämförelse av befintlig pastörisering med integrerad termofil hygienisering på Kungsängens gårds biogasanläggning i Uppsala

The biogas plant Kungsängens gård, owned by Uppsala Vatten och Avfall AB, produces biogas and biomanure from organic household waste, food processing waste and slaughterhouse waste. In year 2012, 4.4 million Nm3 of biogas were produced from 25 200 tons of waste. Before digestion all substrate is sanitized by pasteurization at 70°C in order to kill pathogens. Another method, integrated thermophilic sanitation (ITS), is of interest in order to decrease the energy demand. The method implies that the substrate is sanitized during ten hours in the digestion chamber, where the temperature is 52°C.

Tungmetaller i lakvatten : avskiljning med mineraliska filtermaterial

Four different kinds of filter-materials with reactive surfaces have been studied concerning their capacity to absorb heavy metals in leachate from a municipal waste deposit. The heavy metals studied were: lead, cadmium, copper, mercury, chromium, nickel and zinc. The leachate contains high levels of dissolved organic carbon (DOC) and has a high pH-value along with a high buffer capacity. These characteristics of the leachate make it difficult to remove pollutants and require efficient filters. The filters that were examined in the report are blast-furnace slag with CaO, sand covered with iron oxides, olivine and nepheline.

Energianalys av hygieniseringssystem : jämförelse av befintlig pastörisering med integrerad termofil hygienisering på Kungsängens gårds biogasanläggning i Uppsala

The biogas plant Kungsängens gård, owned by Uppsala Vatten och Avfall AB, produces biogas and biomanure from organic household waste, food processing waste and slaughterhouse waste. In year 2012, 4.4 million Nm3 of biogas were produced from 25 200 tons of waste. Before digestion all substrate is sanitized by one hour?s pasteurization at 70°C in order to kill pathogens. Another method, integrated thermophilic sanitation (ITS), is of interest in order to decrease the energy demand.

Fröodling av Raj- och rörsvingel i Sverige

Festulolium (Festulolium) and tall fescue (Festuca arundinacea) has not been grown inSweden over a longer period. So far there is no greater area cultivated, but the area isincreasing. Festulolium and tall fescue are expected to eventually replace meadowfescue in many leyseed mixtures to dairy cows in southern and central Sweden. Tallfescue has in recent years become popular again. Festulolium is a hybrid betweenryegrass and fescue.

Betesdrift vid automatisk mjölkning i ekologisk produktion :

An automatic milking (AM) system should be combined with some form of controlled cow traffic to minimize the time spend on fetching cows to milking and to increase the milking frequency. By restricting the hours spent on pasture per day you optimise the AM system use during pasture period. A reason for this is becuase cows do not return to the stable for milking during night which cause that the milking unit stands empty those hours. In organic production it is required that the cows should be able to graze a certain amount of daily dry matter (DM) intake on the pasture. In the county of Dalarna where the farm is located the yield of the pasture is about 3000 kg DM per grazing season and hectar.This means that the pasture area should be 14,25 hectare to 57 milking cows.

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