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258 Uppsatser om Mineral nutrients - Sida 1 av 18

Elementkoncentrationer i gran utmed en markfuktighetsgradient :

One key factor in silviculture today is sustainability. In order to achieve sustainability it may be important to restore lost nutrients to the forest after clearcutting. In order to calculate the removal, you need to know how much of different elements you will find in different tree compartments. The aim of this study was to investigate if the concentration of elements in different tree compartments of spruce (Picea abies (L.) Karst) were related to the moisture conditions of the site. Five plots at Risfallet (60º 21´ N, 16º 13´ E), was placed along a moisture gradient in a 40- year spruce stand.

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.

Hållbar växtnäringshantering i Stockholms län : En aktörsanalys

Plant nutrients are important for all life on earth and are also important as fertiliser infood production all over the world. Because of this, plant nutrients are of great valuebut they also bring problems. As an example, the loss of nitrogen and phosphorusfrom agriculture and urban society's sewage systems contributes to some of today?smajor problems in water environment. Another problem associated with plantnutrients is that finite recourses are used in the production of mineral fertilizers.

Slam ? en outnyttjad resurs i skogsbruket

Every year about 210 000 tones dry weight of sewage sludge is produced in Sweden. Most of the sludge is applied to agricultural land, plantsoil and landfill cover. Sewage sludge contains essential nutrients such as nitrogen and phosphorus. Nitrogen is limiting growth on solid ground in Sweden and can therefore be used as fertilizer to increase productivity. In order that the sludge can be spread to forest land it requires first a conversion of sludge to pellets, to make it more manageable.

Mineral composition of New Zealand monofloral honeys

The objective of this study was to determine the mineral content in ten New Zealand monofloral honeys, in order to distinguish whether New Zealand monofloral honeys are a good source of minerals compared to honeys from other parts of the world. The ten monofloral honeys were collected from a local honey factory (Airborne Honey Ltd, Leeston), Clover, Honeydew, Kamahi, Manuka, Nodding Thistle, Rata, Rewarewa, Tawari, Thyme and Vipers Bugloss honeys were been investigated. The water content, water activity, pH, conductivity, colour and mineral content were evaluated. The water activity was averaged for all the ten New Zealand monofloral honeys and set to 0.59 aw, which indicates a high stability and long shelf life as a food stuff. A strong correlation between total mineral content, pH, conductivity and colour was obtained.

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.

Mineral i jordens inre : Hur kristallstrukturer förändras med tryck

Jordens innandöme är uppdelat i flera olika delar, vilket beror på gravitationen och kemisk differentiering. Skillnaden i tryck, temperatur och kemi mellan jordens skorpa, mantel och kärna är en förklaring till varför mineral ändrar karaktär längre ner i jorden. Djupare ner i jorden ökar trycket, men också temperaturen. Ökat tryck gör att atomerna packas tätare, medan ökad temperatur å andra sidan gör att mineralen expanderar. Detta är en av anledningarna till varför det är så svårt att bestämma stabilitetsområden för mineral, det vill säga vid vilka tryck och temperaturer de är stabila.

Användning av rötrest från kombinerad etanol och biogasproduktion : en jämförelse mellan tre alternativ

Scandinavian Biogas is involved in the planning of a combined ethanol and biogas factory in Karlskoga, Sweden. Besides biogas and ethanol large amounts of digester residues will be produced, about 450 000 liquid tonnes residue (~7,3 % Dry Substance( DS)). The objective of this thesis was to investigate possible uses of the residue from the biogas production process ScandgasEthanol developed by Scandinavian Biogas, and to derive a methodological approach how to evaluate and compare handling systems. Three systems where proposed and compared in this thesis; spreading of the untreated residue as fertilizer (system 1), dewatering to a higher DS content to reduce transportation before spreading as fertilizer (system 2) and production of a solid fuel by dewatering and drying the residue (system 3). The general conditions for the proposed systems were investigated in terms of practical viability, economical aspects, environmental impact and energy inputs/outputs.

Produktionsvåtmarker mot övergödning

In ambition to produce more and better harvests, artificial fertilizers are used to produce a better growth of crops in the agriculture landscape. This contributes to leakage of nutrients. Our forests also exhibit a leakage of nutrients. Air pollution contributes to more nutrients. High precipitation with high water flows as a consequence seems currently to occur more frequently in the county of Halland.

Varmhållen och kyld skolmat : En jämförelse med fokus på energianvändning mot bakgrund av livsmedelssäkerhet och näringsretention

The aim of this report has been to investigate the use of electricity energy before and after a conversion of foodservice. The ambition was also to highlight the food safety and the retention of nutrients in relation to the conversion. The methods being used were qualitative interviews, case studies, study visits and literature. The equipment and the use of energy was the same in 2008 as in 2011 for hot-holding of the tested component, sauce with ham. The chilled system used more than three times the energy and cost for one portion than one portion in the hot-hold system.

Vingårdar i Sverige! : farligt för miljön?

The future climate of Sweden is expected to become warmer in the future. This would be beneficial for vineyards and may lead to a greater area being allocated for wine production. The environmental impact concerning eutrophication from Swedish vineyards has not been evaluated before. In this study nutrient balances are constructed for four Swedish vineyards with the goal to estimate the out and in flows of nutrient in the systems for the year 2010. Interviews with focus on farming practices undertaken during the year are conducted with the farmers.

Konstruktion av en fotobioreaktor för odling av alger : ett småskaligt försök

The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.

Malmmikroskopering - en studie av sulfidmineral från Långbantrakten, Bergslagen, Sverige

De sulfidgruvor belägna i Långbantrakten som studien behandlar ligger i den västra delen av Bergslagen utanför Filipstad i Värmlands län. Opaka mineral (malm) från två mindre mineraliseringar, Näset och Getberget, har studerats med malmmikroskop och mikrosond för att beskriva mineralogin i området. Båda områdena domineras av olika (Cu-Fe-Pb-Zn)-sulfider, i Näset av kopparkis (CuFeS2), blyglans (PbS) och zinkblände ((Zn,Fe)S) och i Getberget av blyglans, zinkblände, kubanit (CuFe2S3) och magnetkis (Fe1-xS). I Näset finns en del mindre frekventa mineral, två olika faser av Co-pentlandit (en nickelrik och en utan nickel), gedigen Sb och Bi, (Ni-Co)-sulfid, breithauptit (NiSb) och magnetkis. Kubanit är även ett viktigt mineral som speglar mineraliseringens bildning.

Gestaltningsförslag för Norbyvreten : från kvarterspark till stadsdelspark

The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.

Magasin för lagring av vatten och växtnäring

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

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