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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
771

Moisture and Temperature Effects on the Transformations of Nitrogen from Applied Ammonium Sulfate in a Calcareous Soil

Justice, John Keith 01 May 1961 (has links)
nitrogen has commonly been a deficient element in the cultivated soils of the world since the beginning of agriculture. The general acceptance of the practice of using manures as a means of increasing plant growth, as shown by the records of ancient civilizations, attest to this fact. Since the time of von Liebig there has been an increasing awareness of the importance of this deficiency in soils. As a result of a better understanding of the problem and the increasing availability of commercial forms of nitrogen, a rapid increase in the use of nitrogen fertilizers has taken place in the last few decades. this increasing use of commercial forms of nitrogen is accompanied by the need for more information concerning the proper use of these materials in order to accomplish the greatest benefit. For example, with the advent of increasing use of ammonium fertilizer to improve soil productivity, there has arisen a possibility of lengthening the period from the date of the fertilizer application to the time of utilization by the crop. this advanced application, especially in the fall of the year, has many advantages and is widely advocated. The following questions need to be answered in connection with efficiency of such a practice: Will the ammonium form of nitrogen remain unoxidized in the soil over the winter months? Could it be only partially oxidized and result in an accumulation of nitrites that may cause toxicity or be lost from the soil in gaseous forms such as nitrous oxide? What are the chance for significant losses by volatilization before it is oxidized? How does the amount of moisture and the prevailing temperature affect these transformations? The study reported here is an endeavor to contribute to more complete answers to some of these questions. Although much research has been conducted relating to the effects of moisture or temperature on nitrogen transformations in the soil, more information is needed covering greater variations in the moisture and temperature levels along with the interactions of these. Accordingly, experiments were conducted under carefully controlled conditions to measure the changes occurring in the inorganic soil nitrogen from an applied ammonium source, at various moisture and temperature levels.
772

Seasonal Course of Root Respiration in Atriplex confertifolia

Holthausen, Richard S. 01 May 1977 (has links)
Root respiratory response of mature Atriplex confertifolia plants growing in established communities was measured during two growing seasons using freshly excised root segments and gas chromatography techniques. Respiratory response at fixed test temperatures changed significantly during the growing season, and this pattern of respiratory adjustment varied for root segments located at different depths in the soil profile. Respiration measured at a constant test temperature was highest during early sumner, and declined to minimum values in late summer and fall. Root segments taken from the top 30 cm of the soil profile displayed peak activity several weeks before root segments from greater depths reached maximum activity. The significance of these patterns of respiration is discussed in relation to the carbon balance of Atriplex plants and the uses of respiratory energy within the root system.
773

Basalt rock in sugarcane grown in Ferralsols : Changes in crop yield and in soil chemistry, mineralogy, and microbiology /

Tarumoto, Miriam Büchler. January 2019 (has links)
Orientador: Carlos Alexandre Costa Crusciol / Banca: Fernando Dini Andreote / Banca: Heitor Cantarella / Banca: Antonio Carlos de Azevedo / Banca: Eder de Souza Martins / Resumo: Since the sugarcane production mostly in highly weathered Brazilian soils, an alternative to increasing its yields, renewing these soils is required. Remineralization consists in add milled rock into the soils, as a soil conditioner, providing some minerals and elements. Besides the low cost, the consequences of their application are not totally elucidated. Therefore, the hypothesis of this study include the basalt rock dust treatment can improve the sugarcane yield, soil and plant chemical attributes; basalt rock dust increases the microbial index of soil quality; the rock application change microbial communities in the soil; and the rock weathering change the soil mineralogy. The aim of this study was evaluate the effects basalt rock dust application on sugarcane crops its consequences in soil mineralogy and microbiology. Despite not consistent to the four areas, basalt rock dust treatment can improve the sugarcane yield, soil chemical attributes, and microbial index of soil quality but a little is noticed in plant chemical attributes. The microbial diversity was not the same to the four areas, but it can be more related to geographical patterns than rock application, even with a little shift occurring, it cannot be attributed to the treatment. Weathering signals were noticed but there are two questionable points: the time to occur this weathering, may be quicker than it was thought, and the amount of weathered minerals. Basalt rock dust application improves sugarcane yield... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Visto o cultivo de cana-de-açúcar principalmente em solos brasileiros altamente intemperizados, é necessária uma alternativa para aumentar essa produção, renovando os solos. A remineralização consiste em adicionar rocha moída nos solos, como um condicionador de solo, fornecendo alguns minerais e elementos, além do baixo custo, as consequências desta aplicação não são totalmente elucidadas. Portanto, a hipótese deste estudo inclui o tratamento do pó de rocha basáltica, que pode melhorar o rendimento da cana-de-açúcar, os atributos químicos do solo e da planta; o pó de rocha de basalto aumenta o índice microbiano de qualidade do solo; a aplicação da rocha altera as comunidades microbianas no solo; e o intemperismo das rochas altera a mineralogia do solo. O objetivo deste trabalho foi avaliar o efeito da aplicação de pó de rocha de basalto na cultura da cana-de-açúcar, suas consequências na mineralogia e na microbiologia do solo. Apesar de não ser consistente com as quatro áreas, o tratamento de pó de rocha de basalto pode melhorar o rendimento da cana-de-açúcar, os atributos químicos do solo e o índice microbiano de qualidade do solo, mas pouco é notado nos atributos químicos da planta. A diversidade microbiana não foi a mesma para as quatro áreas, mas pode estar mais relacionada aos padrões geográficos do que à aplicação da rocha, mesmo com uma pequena mudança ocorrendo, não pode ser atribuída ao tratamento. Sinais de intemperismo foram notados, mas há dois pontos questionáveis: o tempo para ocorrer este intemperismo, pode ser mais rápido do que se pensava, e a quantidade de minerais intemperizados nesse tempo. A aplicação de pó de rocha de basalto melhora o rendimento da cana-de-açúcar, destacando-se suas mudanças mineralógicas no solo e não causa danos à diversidade microbiana do solo. A atividade microbiana e as pistas da microbiologia do solo ... / Doutor
774

Förslag till modell av kemikaliespridning i mark anpassad för användning vid räddningsinsats - Kemspill Mark 4.0

Alsterhag, Elin January 2005 (has links)
<p>After emergencies involving chemical spills it is of great importance that correct measures are taken with short notice, both for the security of people and in order to minimize future environmental consequences. The RIB-unit at the Swedish Rescue Services Agency initiated this study, the aim of which is to propose changes to the existing chemical transport calculation tool: Chemical Spill 3.4, included in RIB - Integrated Decision Support for Civil Protection, so that it can be used for decision support as well as in preventive work. A rough estimation of chemical transport in the subsurface is considered being of great importance when making decisions during emergency response operations.</p><p>The proposition presented in this report is a non site specific chemical transport model which is designed to give a rough estimation of NAPL flow in homogenous isotropic soil shortly after an instantaneous release. The model can be used at two levels; both in situations without access to information on subsurface properties, and with more accuracy in situations with knowledge of the included parameters. For that reason the user can choose among predefined alternatives or assign the parameters a numeric value to increase the quality of the model output. The predefined alternatives are represented by default values for different parameters in the model.</p><p>Suggested model output are vertical and horizontal transport of NAPL phase, horizontal transport of dissolved chemical in the aqueous phase, as well as the amounts of spill that are evaporated and entrapped in the soil, all at the time specified by the user. Moreover the maximum transport of the chemical phase and time to groundwater pollution are given. To make the uncertainty of the model clear for the user the results are given as the most likely value together with the smallest and largest values that can be expected.</p><p>Equations presented in this report describe a selection of subsurface processes which occur after a release of chemicals. The selection is made with the aim to reach satisfying result when the model is used within its domain without making the model complicated for the user. Therefore simplifying assumptions have been made in the descriptions of some processes while some other processes are neglected. Simplifications have been based on recognized references or on theoretical arguments, but the overall performance of the model as well as some of the default input parameters need to be further tested and validated before the new version of the model can be included in RIB. However, compared with the existing version Chemical Spill 3.4 several changes have been suggested; including additional processes, development of default values and making model uncertainty clear to the user. These changes are thought to significantly improve the existing model.</p> / <p>Vid olyckor med kemikalieutsläpp är det av stor vikt att rätt åtgärder snabbt vidtas, både för människors säkerhet och för att minimera framtida miljökonsekvenser. Räddningsverkets RIB-enhet initierade den här studien vars mål är att ge förslag på modellteknisk förbättring av det befintliga beräkningsprogrammet Kemspill Mark 3.4, som ingår i programpaketet RIB - Integrerat beslutsstöd för skydd mot olyckor, så att det i framtiden kan användas som beslutsstöd vid räddningsinsats efter kemikalieutsläpp samt vid förebyggande planeringsarbete. En grov vägledning om kemikaliens spridning anses vara av stor betydelse för att räddningstjänsten ska kunna fatta rätt beslut vid en insats.</p><p>Förslaget som presenteras i denna rapport är en icke platsspecifik spridningsmodell anpassad för vätskor med begränsad löslighet i vatten och ger en grov uppskattning av spridning i homogen och isotrop mark inom några timmar efter ett momentant utsläpp.</p><p>Modellen ska kunna användas på två nivåer; för att ge en mycket grov uppskattning av spridningen även utan tillgång på uppgifter om markegenskaper, samt med större noggrannhet då informationen finns. Med anledning av detta kommer användaren ges möjlighet att välja bland fördefinierade alternativ eller att ange indata numeriskt för att öka noggrannheten. De fördefinierade valen representeras av typvärden för olika parametrar i modellen.</p><p>Den nya modellen i förslaget ger vid angiven tid vertikal och horisontell spridning av fri kemikaliefas, horisontell spridning av löst förorening i vattenfas samt hur stor andel av utsläppet som hålls kvar i marken respektive har avdunstat från spillytan. Dessutom anges kemikaliefasens maximala spridning och hur lång tid det tar för utsläppet att nå grundvattnet. För att tydliggöra modellens osäkerhet för användaren ges utdata som det mest sannolika värdet tillsammans med det största och minsta värdet som är sannolikt.</p><p>Ekvationerna som presenteras i rapporten beskriver ett urval av de processer som sker i marken vid ett kemikalieutsläpp. Urvalet har gjorts med utgångspunkt att uppnå tillfredställande resultat inom modellens domän utan att komplicera för användaren och därmed har förenklande antaganden gjorts för att beskriva vissa förlopp medan andra försummats helt. Förenklingarna har grundats på vedertagna referenser eller på teoretiskt resonemang. Validering av modellresultat samt vissa typvärdens intervall krävs före inkludering i RIB. Jämfört med det befintliga Kemspill Mark 3.4 har dock stora förändringar föreslagits; fler processer inkluderas, typvärden utvecklas och modellens osäkerhet görs tydlig för användaren. Förändringar tros medföra en signifikant förbättring av modellen.</p>
775

Human Decomposition Ecology at the University of Tennessee Anthropology Research Facility

Damann, Franklin Edward 01 December 2010 (has links)
The University of Tennessee Anthropology Research Facility (ARF) is well known for its unique history as a site of human decomposition research in a natural environment. It has been integral to our understanding of the processes of human decomposition. Over the last 30 years 1,089 bodies have decomposed at this 1.28 acre facility, producing a density of 850 corpses per acre of land. This project evaluated the abiotic and biotic characteristics of the soil exposed to various levels of human decomposition in order to determine the effect on the physicochemical properties and the indigenous bacterial communities. Specifically, 75 soil samples were taken to determine abiotic properties. A biological matrix was generated for the 40 samples inside the facility based on sequencing of the 16S rDNA gene. The identified taxonomy was evaluated for differences among decomposition bins and taxa. Results of the abiotic soil properties demonstrated few differences among the predefined bins of decomposition density. Significant differences were observed between samples inside the facility to the negative control, and to those samples taken below actively decomposing corpses. When taken together, the abiotic data demonstrated a temporal shift away from control, with the greatest deviation at 18 to 24 months. After which time, the samples became more similar to control samples. Similarly, the biotic data remained concordant with the abiotic data, but demonstrated significant differences between the areas of high decomposition to those with no history of decomposition. The high decomposition bins were marked by high levels of chemoorganotrophic and sulfate-reducing bacteria, and a reduction in Acidobacteria, indicating a change in the community of underlying bacteria in response to carcass enrichment and ammonification of the soil. Thirty years of decomposition research at the ARF has forced a shift in the underlying bacterial community in response to the enrichment of the soil with increased nitrogen and carbon-containing compounds. The baseline data presented in this work provides a control dataset for further exploration regarding the biogeochemical relationships among microbial organisms, soil characteristics, and cadaver decomposition. Within this relationship exists the potential for developing new models relating to postmortem interval estimation and clandestine grave location.
776

The Effects of Changes in Water Content on Uranium(VI) Leaching in Sediment Mixtures Containing Gravel

Moore, Andrew Weber 01 August 2010 (has links)
This study is aimed at understanding the physical and chemical effects that changes in water content have on uranium leaching in sediment containing gravel. It was hypothesized that leaching will be more efficient under unsaturated conditions because flow will be restricted to the smallest pores and will have the most contact with the uranium contaminated sediment. Under saturated conditions, a large portion of the flow will bypass the < 2 mm material, and in turn not come into contact with uranium contaminated material. Batch adsorption and desorption experiments were performed on < 2 mm ERDF sediment to determine the linearity and reversibility of sorption processes and to aid in the interpretation of the leaching experiments. Results of the desorption experiments on aged, contaminated sediments show that the mass percent of sorbed U(VI) released to solution decreased as the sorbed concentration of U(VI) decreased. The opposite trend was observed on freshly contaminated sediments. This indicated that aging increased U(VI) affinity for the solid phase and was attributed to either the crystallization of calcite, which incorporated a portion of the sorbed U(VI) as it crystallized, or the presence of voids in basaltic lithic fragments accessed by diffusion. Column leaching experiments were performed at two water contents on artificially contaminated sediment collected from the Department of Energy’s (DOE) Hanford Site, Washington state. The sediment contained 81.3% gravel (> 2 mm) by mass. Non-reactive tracers were well fit with the convection-dispersion equation (CDE) at both high and low water contents indicating physical equilibrium. The column experimental data were fitted to an analytical solution to the CDE; the results of the modeling show an increase in the distribution coefficient (Kdeffective) with decreasing water content. Several potential explanations for this trend were proposed; one is based on a physical effect in which solute exposure to reactive surfaces changes as a function of water content and the others are based on results of the batch desorption experiments. This work has important implications for the Hanford Site where there is ongoing research regarding the persistence of U(VI) in the vadose zone and underlying aquifer.
777

An Investigation for the need of Secondary Treatment of Residential Wastewater when Applied with a Subsurface Drip Irrigation System

Hillenbrand, Boone S 01 August 2010 (has links)
The objective of this study was to investigate the need for domestic wastewater to receive secondary treatment when being applied to the soil by subsurface drip irrigation (SDI). SDI uniformly distributes wastewater into the soil, which optimizes the soil’s chemical, physical, and biological capacity to remove waste constituents. Because of these advantages, many regulatory jurisdictions are allowing SDI at sites that previously were prohibited from using conventional trench-based soil application systems because of shallow soil restrictions. However, most of these regulatory agencies also require that the wastewater receives secondary treatment (dissolved organic carbon reduction) before the SDI system. At issue is whether the enhanced soil-based renovation provided by SDI should eliminate the necessity for secondary treatment before SDI. Two SDI systems were installed and monitored at two sites in Tennessee. These locations were residential developments served by a septic tank effluent pump (STEP) collection system, a recirculating media filter (fine gravel media), and SDI dispersal. At both locations, SDI plots were established to receive primary treated (septic tank effluent) and secondary treated (recirculating media filter effluent) wastewater. In close proximity to randomly selected SDI emitters, soil samples were extracted. Soil cores were analyzed to determine saturated hydraulic conductivity (Ksat), and pore water samples were analyzed for nitrate, total nitrogen, total carbon, and total phosphorus. Results indicate that the primary-treated sites had lower Ksat values, higher nitrate and higher total nitrogen levels than the secondary-treated side and the background soil. Interestingly, the primary treated side had less total carbon and the background phosphorus concentration was twice that of the primary and secondary treated sides. Primary effluent showed a decrease in concentration for all constituents with increased depth. Secondary treatment does result in a higher quality effluent but is not needed when applying effluent with a SDIS.
778

Inventory, Characterization, and Classification of Minesoils in the Big South Fork National River and Recreation Area

Jones, Cassi Savage 01 August 2011 (has links)
The aim of Part One was to discover and investigate the physical and chemical properties of coal minesoils occurring within the Big South Fork National River and Recreation Area (BSF) in order to better understand the nature of these anthropogenic soils. In particular, this information was to identify which, if any, un-reclaimed or recently reclaimed minesoils were actively producing acid mine drainage (AMD) and what properties were inhibiting revegetation. Historical knowledge and maps were used to locate more than 30 un-reclaimed and reclaimed minesoil sites, which were mapped with GPS. Soil profiles were exposed on 18 sites and grab samples taken on another 12. The morphological properties of each full profile were described according to the National Soil Survey Handbook and samples were taken from each horizon. Chemical properties analyzed for include: particle size, acid-base account, pH, exchangeable aluminum, manganese oxides, soil organic carbon, cation-exchange capacity, exchangeable bases, Mehlich I-extractable elements, and total elemental concentrations. Significant differences in the following properties (averaged) were discovered between the un-reclaimed and reclaimed minesoils: slope, percent rock fragments, dominant lithology, net neutralization potential, pH, extractable aluminum, base saturation, several Mehlich I-extractable nutrients and total elemental concentrations. Hierarchical clustering analysis revealed similar findings and also highlighted instances where reclaimed minesoils were statistically more similar to un-reclaimed minesoils than to other reclaimed minesoils. This indicated that reclamation efforts may not have been completely successful on these sites. In Part Two, minesoil profiles were classified according to Soil Taxonomy and according to proposed amendments by the International Committee for Anthropogenic Soils (ICOMANTH). The ICOMANTH amendments provided more informative classifications for coal minesoils in the BSF however, shortcomings were noted. Additional recommendations were made and the minesoils were again classified according to these recommendations. Compared to both the Soil Taxonomy and the ICOMANTH classifications, those according to the proposed additional amendments revealed more of the unique properties of the minesoils studied in this project. The results of this study can aid the National Park Service with future land management of the minesoils located within the BSF boundaries and other users of drastically disturbed minesoils.
779

Miljöteknisk undersökning enligt MIFO : en studie på fastigheten Bodsjölandet 1:14 avseende den nedlagda tjärfabriken i Grötingen

Ed, Maria January 2006 (has links)
During 40 years of industrial production, from the end of the 1890’s until the end of 1930’s, coal and wood distillation products were manufactured in AB Carbo’s tar factory along the River Gimån in Grötingen, in the county of Jämtland, Sweden. In accordance with the Swedish Environmental Protection Agency’s Methods for Inventories of contaminated sites, MIFO, the site in Grötingen has been identified as a potentially contaminated site. In order to determine whether toxic substances pose a threat to human health and ecological systems in the area, there was a need to investigate the presence of contaminants, their levels and potential for migration. Sensitivity and protection value regarding exposure of man and the environment at the site is high, since people live next to the site and River Gimån is a part of the Natura 2000 network. The initial phase of the MIFO method includes a preliminary survey. Information regarding AB Carbo’s activities and production has been obtained by studying map and archive material, as well as by interviews and site inspections. Potential point sources have been identified around the factory forge, storage cellar, distillation building and the wooden channel for the discharge of tar and other condensates into the River Gimån. Guided by the information gathered in MIFO phase 1, a preliminary site investigation was carried out at the site. It included sampling of soil, sediment, groundwater and surface water together with sample analysis of heavy metals and organic pollutants. The result of the analysis shows that very high levels of the contaminants PAH, aromatics and lead are found in both soil and groundwater. The sediment contamination level is high while that of surface water is very low. The distribution of contamination levels among the samples indicates a likely point source close to the distillation building due to very high contamination levels in soil and groundwater close to that point. The point source may represent a larger spillage or dumped waste products. Two of the contaminants present at the site, phenantrene and phenol, were studied by using the model CHEMFLO-2000. The analysis focussed on mobility in unsaturated soils under conditions that prevail at the site in Grötingen. The adsorption of phenantrene is significantly higher in comparison to that of phenol. Comprehensive assessment and risk classification results in risk class 2 for the site in Grötingen, which implies a need for further investigations and measurements. The risk of human exposure could be reduced by removing contaminated soil around the factory forge. Additional studies should focus on finding the location of the point source around the distillation building as well as contaminant migration from the wooden channel and the geographical spreading of heavy metal contamination. / Från slutet av 1890-talet och fram till slutet av 1930-talet tillverkades träkol och trädestillationsprodukter vid AB Carbos kolugnsanläggning i Grötingen, Jämtlands län. En undersökning enligt MIFO-modellen motsvarande fas 1 och fas 2 har genomförts på området med syfte att fastställa vilka föroreningar som förekommer på området, föroreningsnivå, spridningsförutsättningar och sammanfattningsvis bedöma föroreningssituationen på området utifrån de miljö- samt hälsorisker som området ger eller kan ge upphov till. Objektsområdet har hög känslighet och högt skyddsvärde då människor bor permanent alldeles intill objektsområdet samt att det intilliggande vattendraget Gimån ingår i Natura 2000-nätverket. Genom de orienterande studier som genomfördes i MIFO fas 1 har kart- och arkivstudier samt intervjuer resulterat i information om kolugnsanläggningens verksamhet samt tillverkade produkter. På fabriksområdet identifierades potentiella punktkällor vid fabrikens smedja, källare, reningsverk samt vid den träränna varigenom spilltjära släpptes ut till Gimån. Utifrån den information som erhölls i den orienterande fasen genomfördes en riktad provtagning enligt MIFO fas 2 i såväl mark och sediment som grund- och ytvatten. Bedömning av uppmätta föroreningshalter baseras på riktvärden och skattas från mindre allvarliga till mycket allvarliga. Analysresultaten påvisar allvarliga till mycket allvarliga halter av PAH, aromater och bly i jorden och grundvattnet. Andra föroreningar som påvisas i högre halter på området är alifater och koppar. Föroreningsnivån med avseende på PAH i sedimenten bedöms som allvarlig medan analysresultaten från ytvattenprovtagningen påvisar mycket låga föroreningsnivåer. Provtagningsresultaten påvisar ett mycket förorenat grundvattenflöde från reningsverket, där en punktkälla i form av större spill eller nedgrävda förvaringskärl kan vara lokaliserad. Eventuell spridning av föroreningar från trärännan går inte att fastställa då föroreningsspridning även kan ske från det intilliggande området där kolugnar och kondenseringshus har varit lokaliserade. Föroreningarna fenantren och fenol studerades genom modellering i CHEMFLO-2000 med avseende på deras rörlighet i omättad jord under de geohydrologiska förhållanden som råder på objektsområdet i Grötingen. Resultatet visar att fenantren adsorberas i marken i betydligt större grad än fenol. Koncentrationen fenantren i porvattnet minskar nästan lika mycket som den totala koncentrationen fenantren i marken, vilket tyder på att fenantren binds starkt genom adsorbtion i marken. Den samlade riskbedömningen av objektet resulterar i att objektet bedöms tillhöra riskklass 2, vilket innebär att objektet ger upphov till en stor risk för människa och miljön. Fortsatta undersökningar på området i Grötingen bör fokusera på att hitta den punktkälla vid reningsverket som bedöms vara orsaken till de höga föroreningsnivåer som uppmättes i grundvattenrör V1. Den geografiska utbredningen av de ytliga föroreningarna som påträffades där smedjan har stått bör också utredas vidare och eventuellt avlägsna förorenad jord eller vidta åtgärder för att minska exponeringen. Vidare undersökningar bör även klarlägga spridningen från trärännan samt orsakerna till de höga föroreningsnivåer av bly som uppmättes på området.
780

Torkat bioavfall som jordförbättringsmedel / Dried Biowaste as a Soil Conditioner

Blad, Sofia January 2007 (has links)
The main project Dry preservation of source-separated organic household wastes involves a new technique for treatment of biowaste through drying. Investigations are going on to determine how the dried biowaste best can be used to close the natural circular flow of nutrients. The objective of this degree project is to determine if the dried biowaste can be used as a soil conditioner. By restoring the nutrients in the material to the ground, the natural circular flow is closed. A declaration of contents, including the nutrient levels, C/N ratio, pH and the electrical conductivity of the dried biowaste, was constructed and a germination test was done to make sure that the material did not inhibit sprouting. Further on a method was developed to study the decomposition process, and in particular the nitrogen mineralization of the dried biowaste. This method was then used practically. The results of this degree project indicate that the decomposition capacity of the dried biowaste is very good. The germination test showed that the material in a diluted form (up to 50 % dried biowaste) did not inhibit sprouting. The examination of the nitrogen mineralization showed a fast liberalisation of nutrients available to plants, with only a shorter period of nitrogen immobilization. Together these results imply that the dried material could function well as a soil conditioner. / Projektet Torrkonservering av matavfall från hushåll innefattar en helt ny teknik för behandling av bioavfall genom torkning. Undersökningar pågår angående hur det torkade bioavfallet bäst kan användas för att sluta det naturliga kretsloppet. Examensarbetets huvudsyfte var, som ett led i dessa undersökningar, att utreda om det torkade bioavfallet kan användas som ett jordförbättringsmedel. Genom att tillföra bioavfallet till jord så återförs näringen i materialet till marken och kretsloppet sluts. En varudeklaration, med materialets näringshalter, C/N-kvot, pH och elektrisk konduktivitet, togs fram och ett groningstest utfördes för att kontrollera att bioavfallet inte var groningshämmande. Vidare utvecklades en metod för att studera det torkade bioavfallets nedbrytningsegenskaper i form av dess kvävemineralisering. Denna metod användes därefter praktiskt. Resultatet av detta examensarbete tyder på att torkat bioavfall har mycket goda nedbrytningsegenskaper. Groningsförsöket visade att materialet i utspädd form (upp till 50 % torkat bioavfall) inte är groningshämmande, och mineraliseringsförsöket visade på en snabb frigörelse av växttillgängligt kväve, och en immobiliseringsperiod på ett par veckor. Tillsammans indikerar dessa resultat att det torkade materialet kan fungera väl som ett jordförbättringsmedel.

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