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1261 Uppsatser om Organic matter - Sida 15 av 85
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)).
Frigörelse av fosfor från färskt, fryst och torkat växtmaterial : ett laboratorieförsök för att öka förståelsen för fosfordynamiken inom växtodlingen
Phosphorus is the single most potent contributor to eutrophication of freshwater and has also been shown to contribute to the toxic algae blooms in the Baltic sea. The
dynamics and paths of losses of phosphorus from arable lands are not fully understood.
It is known that phosphorus can be lost directly from plant material to water.
In studies where plant material has been subjected to several freeze-thaw cycles, large amounts of phosphorus have been lost. Most studies have been conducted
under field conditions, with many factors effecting the measured losses of phosphorus, such as weather and type of soil. This study was performed in a controlled environment without the presence of soil. Instead of soil, small glass beads were mixed with the plant materials in vessels, to make possible homogeneous leaching with water through the mixture of glass beads and plant materials.
In this study, clover, ryegrass and dry straw were cut to pieces, approximately 2 cm long.
Piano, gitarr och dragspel : Kön och instrumentval inom Eskilstunas kommunala musikskola och högre musiklinje åren 1980-2000
The aim of this study is to describe how nature is portrayed in swedish poet and critic Aase Berg?s two earliest poetry collections, Hos rådjur (1997) and Mörk materia (1999), and how it relates to notions of humanity, culture and civilisation. The concept of ?nature? is problematized in a short survey of how it has been used by and critizised in ecocritical literary theory, which is used as the main theoretical framework for this survey, with an emphasis on selected theoretical concepts by Donna Haraway. As a methodological starting point, ?nature? is tentatively defined as ?that which does not let itself be subsumed under the human, culture or civilisation?, and this definition is contrasted with how the concepts are handled in the texts.The investigation shows that the relationship of nature to the human is a fundamental theme that provides a structure for both poetry collections.
Optimering av den kemiska reningen vid Fläskebo deponi
Landfill leachate contains a variety of contaminants and is created when rainwater percolates the landfill. For landfill management the leachate is the main issue that can cause problems to the environment. At the landfill of Fläskebo, Renova AB treats the leachate in a local treatment plant. The treatment consists of a chemical treatment step with chemical precipitation, flocculation, sedimentation and filtration, and a final step with a carbon and peat filter. Renova has to ensure that the condition of the leachate reaches the regulation set for the landfill before it is released to the recipient.
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.
Bistånd och korruption : Hur hanteras korrupta regimer av biståndsgivare?
Bachelor essay in political science by Linus Johansson, fall of 2006?Aid and corruption: How do aid donors handle the corrupt regimes??.Supervisor: Jan Olsson.The purpose of this essay is to describe the aid relation between donors and corruptgovernments, to find out whether donors reckon on the problems with implementation of aidto corrupt governments when they decree their aid policy. There are a lot of different ways toimplement the economic aid that are being used by the donors today, and this essay will try toexemplify the different methods of implementing the economic aid. To elucidate the relationbetween donors and corrupt regimes, the essay analyzes three themes: the first two questionsare about the policies used by the donors, and the third question are used to shed light on theactual implementation of aid to corrupt governments. The three themes are: i) Different aidpolicies used by the donors ii) Do donors use particular policies against corrupt regimes? iii)Do corrupt regimes receive less foreign aid? This study stresses the fact that donors do notact like a group unit in the matter of development assistance policy, instead they act inseveral separate groups, this may complicate the endeavour of making economic aid effective.The conclusion of the essay is that corrupt governments are treated the same way that lesscorruptedgovernment are, nothing today indicates that donors would give less economic aidto the corrupt regimes.
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.
Stadsodling : möjligheter och begränsningar
Urban farming can be viewed in several contexts. The first part of this work brings up the beneficial effects of farming on our physical and mental health, knowledge as well as on social life in cities. The introduction of gardening in schools can contribute to an increased awareness on both agricultural practices and importance as well as ecological processes. It can also be used in teaching of other subjects. Farming can also contribute to improving the household economy, and the economy on a municipal or national level.
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.
Möjligheter att öka effektiviteten och det ekonomiska utfallet av barkhanteringen vid Seskarö sågverk :
The sludgebark and to a certain extent the bark were until a decade ago waste products without any economic value that were thrown away. A number of environmental laws and increcing energy prices have improved the prerequisites for increasing the use of these materials. At Seskarö sawmill they burn the sludgebark and a great deal of the bark in the sawmill furnace. The sludgebark has a number of disadvantages compared to bark during burning. The sludgebark is often wet which means the energy net from burning often gets low.
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.
Alternativa stråbränslen i växtföljden :
The purpose of this report is to find out which crops, that are good for strawfuel, and can be grown i the area around the city of Lund. The background of this report it that Lunds energy is planning to bild a biofuelheated thermal power station in Örtofta outside of Lund.
I have in the report limited me to the crops hemp, whole crop (triticale), reed canary
grass, elephant grass and jerusalem artichoke. I have through a documentary research
checked the crops, cultivabillity in the south of Sweden, and how they should fit, in the
Scanian crop sequence.
Hemp is an annual crop which probably could manage in the Scanian crop sequence.
Whole crop often triticale because of it´s high yield and low rate of shed seed. Could
also fit into the crop sequence of crop in Scanian. Triticale is annual, and could be
grown at the same kind of fields as used to wheat, whith is why it would be possible to
grow it in Scania.
Reed canary grass is a reedlike grass that is easy grown at most soils.
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.
Bredspridning av grönmassa :
There are a great possibility to shorten the time between mowing and preservation by spreading of ley crops in connection to the conditioning. In this case the cellular respiration (the plants breeding that consume sugar until the crop is ensiled) should not continue as long and the forage will perhaps get a higher nutritional value. The capacity of the next machine could also be higher because the rake gives swaths with a lot of material. There is also a possibility that spreading of ley crops gives the material a more homogeneous content of dry matter and that gives a reduced growth of clostridium. This is particularly important when the method of harvest doesn?t include any mixing of the material like it does with a round baler or silagewagon.