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133 Uppsatser om Nutrient - Sida 7 av 9

Återvinning av näringsämnen från hushållsspillvatten med omvänd osmos

Hammarby Sjöstad is a new district in Stockholm with high environmental standard. Stockholm Water Company evaluates a local wastewater treatment plant with cutting edge technology. The first step is an experimental treatment plant (Sjöstadsverket) with four parallel lines of treatment, each with a capacity to treat wastewater from 150 persons. Within the membrane technology subproject the possibility of using reverse osmosis (usually called RO) to regain Nutrients is examined.Reverse osmosis separates the incoming water in a clean permeate and a concentrate that, as the name indicates, is a more concentrated version of the incoming water. Using this method in wastewater treatment, a solution high in Nutrients can be obtained without the use of chemical precipitation agent and with no production of sludge.

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.

Ny teknik för kombisådd :

The use of combi-drilling during spring tillage has become very common in southern Sweden in recent years. Combi-drilling leads to fewer passes on the field and better plant Nutrient utilisation. An example of a combi-drill is the Väderstad Rapid, which is very widely used in spring tillage in southern Sweden. The Rapid has separate fertiliser and seed coulters, which means that the draught requirement is relatively high. It thus requires large, heavy tractors, which compact the soil and are comparatively expensive to buy and run. A few years ago the Finnish combi-drill Tume Nova Combi came onto the Swedish market.

En fallstudie om effektivisering av kosthanteringen inom Nybro kommun

In December 2008 the municipal council in Nybro, decided that the municipality shouldreduce the budget for food service. The budget should be reduced by 2 100 000 SEK.They decided that the children- and education committee, and the care committee would haveto lower their budget with 1 264 000 SEK respectively 636 000 SEK. The change have to bedone under two years, 60 % should be done under 2009 and 40 % under 2010.As a result of the decision, many kitchens have to become kitchens that only serve food, notcook it. This will result in preschool staff and nursing staff take over some of the tasks fromthe kitchen staff. The municipal council also decided that entrepreneurs could take over one(later two) cooking areas.A kitchen that serves food means that there isn?t any cooking involved.

Biogas till kraftvärme på Wapnö : en projektanalys utifrån ett företagsekonomiskt perspektiv

Biogas is a gaseous fuel, rich in methane, produced through a biological route in an anaerobic digester. A gas engine generates combined heat and power, which can be used at the farm to reduce energy cost. The process also generates a digestate, with better utilization of Nutrient compared to cattle manure. The aim of this study is to analyze the profitability of a farm-scale biogas plant for combined heat and power (CHP) at Wapnö. Wapnö is an agriculture company located in the southern part of Sweden.

Vårvetesorters effektivitet i användningen av kväve under den huvudsakliga tillväxtperioden

Crop efficiency in utilizing available Nutrients is an important factor in increasing produc-tivity and reducing the environmental impact of agriculture. Nitrogen is the Nutrient that plants need in the largest quantity and wheat, along with maize and rice, is the world's most cultivated crop. In this work, the Nitrogen Use Efficiency, NUE, during the major growth period, HTP, of twelve different spring wheat varieties, were examined. The NUE was calculated as the product of uptake efficiency of nitrogen, UN, and the conversion effi-ciency of nitrogen to biomass, EN. The purpose of this work was to find if there are varietal differences in NUE and its components among the twelve varieties and to link a high NUE to specific characteristics of the varieties.

Effekt av sönderdelningsgrad och planteringsdjup på uppkomsten från rhizom av Tussilago farfara :

Tussilago farfara, coltsfoot, is a troublesome perennial weed with deep lying rhizome, which can vegetatively generate new plants. The mechanical control of coltsfoot that is used today, "starvation", which consists of several cultivations of the soil, which fragmentises the rhizome. This results in production of new shoots, which leads to depletion of Nutrient resources; as long the new plant is not allowed to establish. However, very little research has been done to investigate how the starving technique affects the regenerative ability of coltsfoot. The purpose of this experiment with coltsfoot was to investigate how fragmentation and burial depths affect the time of emergence, number of emerged shoots per rhizome fragment, number of shoots per node, and if the germination ability within nodes changes during the experiment.

Hur bör unga hundar av storvuxna raser utfodras?

The dog is unique in the way that the adult weight can vary 100 folds between the different breeds. Despite this, most of the breeds reach adult size before two years of age. For the large-breed dogs this means a very rapid growth when some of them can have a weight gain of up to 150 times their birth weight. The most rapid growth occurs when the puppies are between three to six months old and that kind of rapid growth during such a short period of time makes these large-breed puppies very sensitive to deficits and excesses of energy, Nutrients and minerals. Some examples can be excess of energy, excess or deficit of minerals such as calcium and phosphorus or deficits of protein. The rapid growth can also make the large-breed puppies predisposed to some diseases affecting the skeletal and joints.

Fosforavskiljning i reaktiva filter vid småskalig avloppsrening

An excessive input of Nutrients to lakes and other water bodies has created a problem with eutrophication in Sweden. Untreated, or partially treated, domestic sewage is a major source for discharge of phosphorus (P), which is the Nutrient most frequently responsible for eutrophication of most fresh waters and the Baltic Sea. The waste water can be cleaned by filter materials, which have a high P-retention ability and which after saturation may be used as fertilizers. Four potentially suitable filter materials were tested in batch- and column experiments in this study. In the batch experiments, the following materials were shaken with waste water in time series ranging from 5 seconds to 60 minutes: coarse (1-4 mm) and fine (0-2 mm) Polonite® (heated bedrock from Poland); Filtralite® (light expanded clay aggregates with limestone added before burning); water cooled blast furnace slag (BF-slag) and BF-slag mixed with 10% burned limestone.

Utveckling av en beräkningsmodell för biogasproduktion

A growing interest for the climate and the environment has led to an increased interest forenvironmentally friendly and renewable energy sources, such as biogas. Planning new biogasplants requires a decision basis including facts about approximate amounts of biogas possibleto produce at the plant. The purpose of this thesis is to develop a model that calculates theapproximate biogas and digestate production from a planned or existing biogas plant.Developing the model required a literature review and studies of calculations concerningbiogas and digestate production performed by WSP Sweden AB. As a complement to themodel development, facts about substrates for biogas production were compiled through aliterature review. In addition the methane potential from selected materials was determined bybatch experiments.

Är kolrika jordar en källa till fosforläckage? : en sammanställning av data från 130 åkerjordar

Phosphorus (P) is an essential Nutrient but a surplus could lead to eutrophication. Furthermore, the minerals used to produce the mineral phosphate is a non renewable resource. There are in other words several reasons to reduce the leakage of P and the agriculture is one important area to attend. The aim of this work has been to investigate if carbon-rich arable soils content contain more P than arable soils with low carbon content. Moreover it has been calculated if the carbon-rich soils could pose a risk of P leakage by comparing their delivery of P with the plant uptake. The work has consisted of compiling the results from former gathered and analysed soil samples of 130 Swedish arable soils. The fractions of P considered are water soluble P (Pw), ammonium lactate-extractable P (P-AL), hydrochloric acid-soluble P (P-HCl), organic ammonium lactate-extractable P (Porg-AL) and inorganic ammonium lactate-extractable P (Porg-HCl).

Site preparation, planting position and planting stock effects on long-term survival, growth and stem form properties of Pinus contorta on southern Iceland

In order to evaluate different afforestation methods for exposed heath lands a field experiment was established in Mosfell on southern Iceland in 1989. The trial comprised six different site preparation methods (control, herbicide application, tree shelters, patch scarification, TTS trenching and mounding). In total 960 container seedlings (1+0) and 960 Nisula roll transplants (2+1) of lodgepole pine were planted. Various planting positions (furrow, hinge, no site preparation (control) and on top of mounds) were tested within the site preparation treatments. This study involves renewed measurements and analyses of the trial.After 19 years the overall survival was 51,7 %.

Hackelselängdens betydelse för tuggtid och foderkonsumtion hos mjölkkor :

Today, our cows experience a harder pressure to achieve higher milk yield. To manage this challenge the animal needs first class feeding and treatment. An important aspect of the feeding is to fulfil the need from the cows of especially fiber; and fiber with a sufficient proportion of long particles. Both too much and too little fiber is bad for the wellbeing of the cow, and she might get diseases like acidosis. Many models for feed management have been developed to secure that the animal gets enough of e.g. fiber with a sufficient proportion of long particles.

Varierad kaliumgödsling i potatis : en fältstudie i Hedemora

Variation in tuber quality within a single field was one of the motives for a pilot study in Halland, in south-western Sweden conducted during 2002. Quality problems in potatoes have been increasing due to the aggregation of several small fields with different land use history into larger farm units, which are heterogeneous in soil properties and fertility. The study in Halland indicated that both the uniformity and the mean size of tubers may increase from site-specific K fertilization, whereas total yields may be unaffected. The results from this pilot-study with site-specific fertilization showed that tubers reached a more uniform quality and gave a more uniform mean size, while the total yield wasn't affected at all. Site-specific K-fertilization has been applied for some years in Halland with good results. The aim of this study was to test this technique in another potato growing area.

Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes

Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and Nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.

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