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175 Uppsatser om Nutrient uptake - Sida 1 av 12

Biologiska behandlingsmetoder för rening av rejektvatten från biogasproduktion

In this literature review the characteristics of two free-floating macrophytes, water hyacinth   (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.

Effect of liming and free Ca2+ on Cd uptake of carrots, Daucus carota

The level of cadmium (Cd) in Swedish arable land has increased during the last century and the average concentration of Cd in the plough layer is today 0.23 mg/kg. The increase is mainly due to anthropogenic activities such as phosphorus fertilizing, liming, import of feed, and atmospheric deposition from industrial emissions. Cadmium in the soil will be taken up by crops and is thereby transferred to humans via food. Carrot is one of the crops of concern, both because it may contain quite high Cd concentrations and due to the large consumption in Sweden. In the body, Cd is stored mainly in the liver and the kidneys and may cause several diseases already at low concentrations.

Förändringar i markanvändning över tid och dess påverkan på vattenkvalitet

The EU Water Framework Directive has led that management follows the boundaries of natural catchments.The Swedish waters suffer from a nutrient overload that originates mainly from diffuse sources such as agriculture and the subcatchment of Hackstabäcken in Vallentuna Kommun, just north of Stockholm, has been chosen for this study because of its high nutrient load and because it has undergone obvious changes in land use through the years.In this study, the land use in 1902 is compared with the land use in 2011 in order to investigate if it has influenced the ability of the landscape to produce ecosystem services related to nutrient removal. These services will continue to be produced as long as the system is stable and resilient, but when landuse changes and manure from horses increases it will lead to disturbances that can convert a system from one regime in to a completely different one. That will result in loss, or degradation, of ecosystem services such as denitrification, phosphor sedimentation and adsorption, vegetation uptake and infiltration.The results of this study are based upon area calculations of landuse from old maps from 1902 and 2011. Through these maps it becomes clear that the forests in Hackstabäcken, has increased with 170 ha together with an urbanization of 311 ha, at the same time as wetlands and arable land has diminished and lakes has suffered from reductions. Wetlands have been reduced with 76 ha and the ones remaining are of insufficient quality from a nutrient removal perspective.Data from 1902 and 2011 regarding number of horses and bovines indicated a decrease in bovines and an increase in horses.

Miljödifferentierad fastighetsskatt

It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.

Effekt av karbonatisering med biogas på aska från trädbränslen

It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.

Alternativa finansieringsmöjligheter av företagsfastigheter

It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.

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.

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).

Ut ur Östersjön genom vassen : beskrivning av övergödningsproblematiken samt optimering av en reningsmetod genom skörd av vattenväxter

This study is based on AgroSeas business idea from environmental problems to valuable resource, with the objective to optimize a method to purify the already eutrophicated Baltic Sea by harvesting water plants, mainly reed. The nutrients will then be recirculated to arable land through residues from biogas production. The amount of nutrients that can be removed by harvesting the biomass depends on the amounts of biomass and the nutrient content of it, which in turn is strongly dependent on the nutrient concentration of the surrounding water. Vegetation suggested in the study for an effective Nutrient uptake is helophytes: reed, cattails, reed canary grass, reed sweet grass in shallower water and lemnoideaes: duckweed and nymphaeids in the deeper parts. Competitive species has high purification ability but requires regular maintenance to avoid channeling and overgrowth. Regarding time and method of harvest, effectiveness may be improved by: harvesting plants above the water level and after flowering, a border is kept, harvesting twice a season, a bigger machine and a regular maintenance. This literature has illuminated a major environmental problem and it has been suggested optimizations for a method for cleaning the Baltic Sea through harvesting water plants, but to get a definite answer for the optimal method for each site tests should be carried out, this because many factors determine to what is suitable for each, specific environment. .

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.

Exosomes as a potential mechanism of intercellular spread of prion protein

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.

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.

Is goat milk a better milk replacement to piglets, rat pups and foals than cow milk is?

AbstractOne opinion among people who are experienced in hand rearing newborn mammals is that goat milk is more suitable than cow milk if the young needs a milk replacer. The purpose of this literature review was to find out if there is scientific evidence that goat milk is a better milk replacer for piglets, rat pups and foals than cow milk. The milk is essential for the newborn animal, as its only source of nutrition until it has learned how to eat solid food. In this literature review, the composition of goat milk and cow milk is compared with the nutrient requirements after birth in piglets, rat pups and foals. The nutrient requirements and the milk composition are partly determined by the newborn mammals activity level and suckling frequency, which also is described.

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.

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.

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