Academic literature on the topic 'Organic matter addition'
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Journal articles on the topic "Organic matter addition"
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Paul, Niladri, Jayeeta Chakraborty, Dipankar Saha, Rajib Ranjan Chakraborty, and Saradindu Das. "Stages of Organic Matter Addition vs. N Transformation in Soil." JOURNAL OF ADVANCES IN BIOTECHNOLOGY 3, no. 2 (July 30, 2013): 183–86. http://dx.doi.org/10.24297/jbt.v3i2.5036.
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FYM and mustard cake, the two variable source of organic matter, were used as amendments and N sources in a typic ustifluvent soil. Organic matters were added at two modes i.e 21 days’ before and on the day of actual start of the experiment. Inorganic N as urea was added as treatment material. Results of the experiment reveal that comparatively higher amount of inorganic N was accumulated in soil incubated at 21 days compared to soils amended with organic matter upto 90 days period. Compared to the sources of organic matters, it was observed that the amount of inorganic N was recorded much higher in mustard cake amended soil than that of the soil amended with FYM. However, the amount of organic N content did not vary much and also did not show any definite trend of changes. The overall result showed that mustard cake proved superior results over that of FYM with regard to accumulation of inorganic N in soil. Addition of organic matters 21 days before the start of the experiment showed better results with regards to availability of N in soils.
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Riggs, Charlotte E., Sarah E. Hobbie, Elizabeth M. Bach, Kirsten S. Hofmockel, and Clare E. Kazanski. "Nitrogen addition changes grassland soil organic matter decomposition." Biogeochemistry 125, no. 2 (June 29, 2015): 203–19. http://dx.doi.org/10.1007/s10533-015-0123-2.
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Raul H. Piedrahita, George Tchobanoglous, and Brendan Moore. "Effect of Organic Matter Addition to Fish Culture Systems." Transactions of the ASAE 30, no. 1 (1987): 0233–37. http://dx.doi.org/10.13031/2013.30432.
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Yusran, Fadly Hairannoor. "The Relationship between Phosphate Adsorption and Soil Organic Carbon from Organic Matter Addition." JOURNAL OF TROPICAL SOILS 15, no. 1 (April 9, 2018): 1. http://dx.doi.org/10.5400/jts.2010.v15i1.1-10.
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The Relationship between Phosphate Adsorption and Soil Organic Carbon from Organic Matter Addition (FH Yusran): The application of organic matter (OM) can increase soil phosphorus (P) availability via soil mineralisation. In lateritic soils, however, soluble organic carbon (OC) from OM may also reduce phosphate adsorption capacity, a process that also releases P in soil solution. In these soils, competitive adsorption could be dominant compared to mineralisation. The main objectives of this study were to study phosphate adsorption in three lateritic soils which have been treated with different types and amounts of organic amendment, and had intrinsic OC removed by combustion. The adsorption isotherms showed that OM addition could reduce phosphate adsorption and that this reduction could last up to nine months after application. Lucerne hay was more effective than peat and wheat straw additions in reducing phosphate adsorption capacity. The bicarbonate phosphorus (BP) release through mineralisation occurred despite the increase of phosphate adsorption capacity due to the combustion of soil samples. Peat treatment was predicted to be more effective in creating organo-metal complexes with Al and Fe. Overall, mineralisation from added organic amendment was effective in minimising P adsorption in lateritic soil.
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Medina, Rocío, Pedro M. David Gara, Janina A. Rosso, and María T. Del Panno. "Effects of organic matter addition on chronically hydrocarbon‐contaminated soil." Biodegradation 32, no. 2 (February 13, 2021): 145–63. http://dx.doi.org/10.1007/s10532-021-09929-y.
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Clostre, Florence, Thierry Woignier, Luc Rangon, Paula Fernandes, Alain Soler, and Magalie Lesueur-Jannoyer. "Field validation of chlordecone soil sequestration by organic matter addition." Journal of Soils and Sediments 14, no. 1 (October 22, 2013): 23–33. http://dx.doi.org/10.1007/s11368-013-0790-3.
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Philben, Michael, Jianqiu Zheng, Markus Bill, Jeffrey M. Heikoop, George Perkins, Ziming Yang, Stan D. Wullschleger, David E. Graham, and Baohua Gu. "Stimulation of anaerobic organic matter decomposition by subsurface organic N addition in tundra soils." Soil Biology and Biochemistry 130 (March 2019): 195–204. http://dx.doi.org/10.1016/j.soilbio.2018.12.009.
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Irham, Muhammad, Saidatul Adhla, and Chitra Octavina. "Analisis kimia sedimen di sekitar ekosistem mangrove desa Lambadeuk, Peukan Bada, Aceh Besar." Depik 9, no. 1 (January 2, 2020): 1–7. http://dx.doi.org/10.13170/depik.9.1.15163.
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Abstract. Research on analysis of sediments chemistry around the mangrove ecosystem of Lambadeuk village, Peukan Bada Subdistrict aimed to the analyze nutrient content of sediments around mangrove ecosystem which grows in Lambadeuk, Aceh Besar. The study was conducted in April 2018 - May 2019. Research stations were determined by using purposive random sampling method then sediment samples were taken by coring technic. The results of the analysis showed that there are two types of sediments; muddy sand and sandy mud type of sediment. Sandy mud sediment has higher organic matter than muddy sand. The percentage value of total organic matters ranged from 27.89% - 42.41%, while C-Organic was between 0.08% - 1.28%. The percentage of dominant C-organic was found in places that are overgrown with mangroves, while the total organic matter content is more in places that does not have mangroves. In addition to the presence of mangroves that affect the amount of organic sediment and type of sediment, oceanographic factors such as currents, topography, organic matter content, and C-Organic are also affect the type of existing sediment.Keywords: Mangroves, Sediment, Organic matter, C-Organic.Abstrak. Penelitian mengenai analisis kimia sedimen di sekitar ekosistem mangrove Desa Lambadeuk, Kecamatan Peukan Bada bertujuan untuk menganalisis kandungan unsur hara sedimen di sekitar ekosistem mangrove yang tumbuh di daerah Lambadeuk, Aceh Besar. Penelitian ini dilakukan pada bulan April – Mei 2019. Metode penentuan stasiun penelitian menggunakan metode purposive random sampling kemudian sampel sedimen diambil dengan menggunakan coring. Hasil analisis menunjukkan bahwa tipe sedimen yang ada di Desa Lambadeuk, Kecamatan Peukan Bada terdapat dua tipe sedimen yaitu pasir berlumpur (muddy sand) dan lumpur berpasir (sandy mud). Tipe sedimen lumpur berpasir memiliki kandungan bahan organik lebih tinggi daripada pasir berlumpur. Nilai persentase kandungan bahan organik total berkisar yaitu berkisar antara 27,89 % - 42,41 %, sedangkan C-organik berkisar antara 0,08 % - 1,28 %. Persentase C-organik lebih banyak terdapat di tempat yang banyak ditumbuhi mangrove, sedangkan kandungan bahan organik total lebih banyak di tempat yang tidak ditumbuhi mangrove sama sekali. Disamping keberadaan mangrove yang mempengaruhi besarnya bahan organic sedimen, faktor-faktor oseanografi seperti arus, topografi, kandungan bahan organik, dan C-organik juga mempengauhi tipe sedimen yang ada.Kata Kunci: Mangrove, Sedimen, Bahan Organik, C-organik.
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Cheshire, M. V., C. Dumat, A. R. Fraser, S. Hillier, and S. Staunton. "The interaction between soil organic matter and soil clay minerals by selective removal and controlled addition of organic matter." European Journal of Soil Science 51, no. 3 (September 2000): 497–509. http://dx.doi.org/10.1111/j.1365-2389.2000.00325.x.
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Chen, Mo, Hui-Qing Sun, and He-Long Jiang. "The addition of FeOOH binds phosphate in organic matter-rich sediments." Chemistry and Ecology 32, no. 5 (February 29, 2016): 432–45. http://dx.doi.org/10.1080/02757540.2016.1150455.
Full textDissertations / Theses on the topic "Organic matter addition"
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Yusran, Fadly Hairannoor. "Soil organic matter decomposition : effects of organic matter addition on phosphorus dynamics in lateritic soils." University of Western Australia. School of Earth and Geographical Sciences, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0120.
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[Truncated abstract] Relationships between the persistence of organic matter added to soil, the dynamics of soil organic carbon (C) and phosphorus (P) were examined in four experiments on lateritic soils of Western Australia. The main objective was to quantify the release of P following organic matter application in soils which have high P adsorbing capacity. Another objective was to confirm that due to its recalcitrant materials, the effect of peat lasted longer in soil than other sources of organic matter in terms of increasing plant-available P fractions. Three experiments were conducted under glasshouse conditions for various lengths of time, with nine- to twelve-month incubations to investigate these hypotheses. As expected, organic matter with lower C:N ratios than peat (lucerne hay) decomposed more rapidly compared with peat, and the most active mineralisation took place within the first three months of incubation. Soil organic-C (extracted by 0.5 M K2SO4) had a significant positive correlation with P extracted with 0.5 M NaHCO pH 8.53. For a higher application rate (120 ton ha-1), peat was better than wheat straw and lucerne hay in increasing extractable bicarbonate-P concentrations in soil, especially at incubation times up to 12 months. Throughout the experiment, peat was associated with a steady increase in all parameters measured. In contrast to peat, nutrient release from lucerne hay and wheat straw was rapid and diminished over time. There was a tendency for organic-C (either in the form of total extractable organic-C or microbial biomass-C) to steadily increase in soil with added peat throughout the experiment. Unlike wheat straw and lucerne hay, extractable organic-C from peat remained in soil and there was less C loss in the form of respiration. Therefore, peat persisted and sequestered C to the soil system for a longer time than the other source of organic matter. Freshly added organic matter was expected to have a greater influence on P transformation from adsorbed forms in lateritic soils than existing soil organic matter. By removing the existing soil organic matter, the effect of freshly applied organic matter can be determine separately from that of the existing soil organic matter for a similar organic-C content. In order to do this, some soil samples were combusted up to 450° C to eliminate inherent soil organic matter. The release of P was greater when organic-C from fresh organic matter was applied to combusted soils than in uncombusted soils that contained the existing soil organic matter. The exception only applied for parameters related to soil micro-organisms such as biomass-C and phosphatase. For such parameters, new soil organic matter did not create conditions favourable for organisms to increase in activity despite the abundance of organic matter available. More non-extractable-P was formed in combusted soils compared to bicarbonate-P and it contributed to more than 50% of total-P. As for the first experiment, peat also showed a constant effect in increasing bicarbonate extractable-P in the soil
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Sjöberg, Gudrun. "Lignin degradation : long-term effects of nitrogen addition on decomposition of forest soil organic matter /." Uppsala : Dept. of Soil Sciences, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/a419.pdf.
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Rocha, Maria da AssunÃÃo Machado. "Answers morphological and physiological woody species under water stress in soil with and without addition of organic matter." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13169.
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The low availability of water in the soil is one of the most limiting factors to plants growth and survival. The objective of this work was to evaluate the responses of morphological and physiological processes in the early stage of growth of guanandi (Calophyllum brasilense Cambess), african mahogany (Khaya ivorensis A. Chev ) and oiti (Licania tomentosa (Benth) Fritsch) for the imposition of severe water stress and rehydration in soil with and without organic matters The experiment was conducted in a greenhouse at the Meteorological Station of the Department of Agricultural Engineering of the UFC , located in Fortaleza (CE). The experimental design was a complete randomized block, factorial 3 x 2 x 2, formed by three species (Guanandi, Mogno Africano and Oiti) two water regimes (irrigated and non- irrigated) and two levels of organic manure (with and without addition of organic matter), with five blocks and two plants per replication. Irrigation was suspended for 15 days on half of the plants , while the other half (controls ) received irrigation continuously. At the end of the stress period the plants were again irrigated for 15 days for determination of recovery, as the experiment lasted 30 days. The following evaluations were performed: gravimetric soil moisture (θ), leaf water potential (Ψw), plant growth, leaf gas exchange, relative chlorophyll index and leaf concentration of mineral nutrients. Drought stress decreased leaf water potential affecting growth, nutrient uptake and physiological responses of plants during the period of stress. And in the recovery period the plants recover turgor, but the recovery in growth, gas exchange and nutrient accumulation presented slower, suggests the these plants require a longer period of recovery. The addition of organic matter in the soil favored the retention of water allowing the water supply to the plants during water deficit by reducing the deleterious effects of water stress on growth, physiological functions and nutrient accumulation during stress. Whereas in the soil with this input period rehydration plants had a better recovery due to reducing the negative effects induced by water stress.A baixa disponibilidade de Ãgua no solo à um dos fatores mais limitantes para o crescimento e sobrevivÃncia das plantas. O objetivo deste trabalho foi avaliar as respostas dos processos morfolÃgicas e fisiolÃgicas na fase inicial do crescimento do guanandi (Calophyllum brasilense Cambess), mogno africano (Khaya ivorensis A. Chev) e oiti (Licania tomentosa (Benth.) Fritsch) durante a imposiÃÃo do estresse hÃdrico severo e a reidrataÃÃo, em solo com e sem adiÃÃo de matÃria orgÃnica. O experimento foi conduzido em casa de vegetaÃÃo, na EstaÃÃo MeteorolÃgica do Departamento de Engenharia AgrÃcola da UFC, localizada em Fortaleza-CE. O delineamento experimental foi em blocos inteiramente casualizados, em arranjo fatorial 3 x 2 x 2, sendo composto por trÃs espÃcies (guanandi, mogno africano e oiti), dois regimes hÃdricos (irrigado e nÃo irrigado) e dois nÃveis de adubaÃÃo orgÃnica (com e sem adiÃÃo de matÃria orgÃnica), com cinco blocos e com duas plantas por repetiÃÃo. A irrigaÃÃo foi suspensa por 15 dias em metade das plantas, enquanto que a outra metade (controle) recebeu irrigaÃÃo continuamente. Ao final do perÃodo de estresse as plantas voltaram a ser irrigadas durante 15 dias para a determinaÃÃo da recuperaÃÃo, assim o experimento durou 30 dias. Foram realizadas as seguintes avaliaÃÃes: umidade gravimÃtrica do solo (θ), potencial hÃdrico foliar (Ψw), crescimento, trocas gasosas foliares, Ãndice relativo de clorofila (IRC), e teores de nutrientes foliares. O estresse hÃdrico reduziu potencial hÃdrico foliar afetando o crescimento, a absorÃÃo de nutrientes e as respostas fisiolÃgicas das plantas no perÃodo de estresse. Sendo que no perÃodo de recuperaÃÃo as plantas recuperam a turgescÃncia, mas a recuperaÃÃo do crescimento, das trocas gasosas e do acÃmulo de nutrientes apresentou-se mais lento, sugere que essas plantas necessitam de um perÃodo maior de recuperaÃÃo. A adiÃÃo de matÃria orgÃnica no solo favoreceu a retenÃÃo de Ãgua permitindo o fornecimento para as plantas durante o dÃficit hÃdrico reduzindo os efeitos deletÃrios do estresse hÃdrico sobre o crescimento, as funÃÃes fisiolÃgicas e o acÃmulo de nutriente no perÃodo de estresse. Sendo que no perÃodo de reidrataÃÃo o solo com esse insumo as plantas tiveram uma melhor recuperaÃÃo, devido à reduÃÃo dos efeitos negativos induzidos pelo estresse hÃdrico.
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Tsuntsaeva, Madina Nukhidovna. "Drinking water purification from natural organic matter by different order addition of alum coagulant and powdered activated carbon." Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/81774.
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Combined coagulation and adsorption process are considered to be the most effective integrated treatment system for removing dissolved organic contaminants in treatment of drinking water. This study conducted series of intensive laboratory experiments to assess the process of alum coagulation and powdered activated carbon adsorption (PAC), and to evaluate the effect of the order of adding alum coagulant and PAC to remove natural organic matter in drinking water treatment.
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Pernot, Audrey. "Réactivité des hydrocarbures aromatiques polycycliques dans une terre de cokerie : influence de réparation des contaminants et de l'introduction de matière organique fraîche." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0237/document.
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La fin des activités industrielles liées au charbon et à son exploitation a laissé de nombreux sites et sols pollués en France et particulièrement dans le Nord-est de la France. Une terre issue d'une friche industrielle de cokerie (Neuves-Maisons, Lorraine, France) est étudiée en couplant les outils de la science du sol et de la géochimie organique afin de comprendre l'évolution à long terme de la dynamique des contaminants. Une première étape de caractérisation de la terre et de sa pollution montre que la fraction limon fin (2-20 µm) est la fraction la plus réactive avec la plus forte concentration en HAP extractible et occlus et la plus faible disponibilité, mettant en évidence des processus de préservation spécifique au sein de cette fraction. Des extractions sélectives de la MO anthropique au solvant, confirmées par des observations au MEB, montrent que la MO anthropique, contrairement à la MO naturelle, n'a pas un rôle de liant entre les particules de la terre. L'apport de MO naturelle, (i) en conditions contrôlées par incubation de débris végétaux pendant 15 mois ou (ii) in situ en parcelles lysimétriques plantées avec de la luzerne pendant 6 ans, conduit à une structuration de la terre, une activité microbienne accrue et à l'incorporation et au stockage de la matière organique fraîche végétale dans les limons fins. En revanche, la pollution n'est pas affectée par l'apport de matière organique fraîche. Ainsi, la concentration et la disponibilité des HAP présentent une tendance à la diminution au cours du temps, que la terre soit cultivée ou non. Ainsi, la matière organique fraîche n'apparaît pas comme un agent de mobilisation de la pollution à long terme pour ce type de terre historiquement contaminéeThe end of industrial activities associated to coal exploitation left many huge areas of wastelands especially in the Northeast of France. A former coking plant soil was studied with a combination of soil science and organic geochemistry tools in order to understand the evolution of the contaminants dynamic. In a first step, the soil and its pollution were characterized. The results showed that the fine silt fraction (2-20 µm) was the most reactive with the highest PAH concentration (extractable or occluded) and the lowest PAH availability. This fraction played a protective role toward the pollution. Moreover, solvent extractions of the anthropogenic organic matter showed that the anthropogenic organic matter was not a structuring agent between the particles in the soil. These observations were confirmed by SEM observations. In a vegetation growth context, (i) under controlled conditions with incubation of organic residue during 15 months and (ii) in situ in lysimetric plots planted with alfalfa during 6 years, the soil structure and the microbial biomass were promoted and the fresh organic matter was preferentially incorporated and stored in the fine silts. However, the pollution was not affected by the fresh organic matter addition. Both PAH concentration and availability showed a trend to decrease with the time of experiment. Thus, the fresh organic matter did not appear as a mobilizing agent for the pollution and would most probably contribute to pollution stabilization on the long term
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Kelso, Julia E. "Organic Matter Sources, Composition, and Quality in Rivers and Experimental Streams." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7354.
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Organic matter (OM) is often considered the “currency” for ecosystem processes, such as respiration and primary production. OM in aquatic ecosystems is derived from multiple sources, and is a complex mixture of thousands of different chemical constituents. Therefore, it is difficult to identify all the sources of OM that enter and exit aquatic ecosystems. As humans develop undisturbed land, the rate at which terrestrial OM (e.g.soil and plants) and associated nutrients (e.g.nitrogen) enters rivers has increased. Increased nutrients may lead to increased primary production from aquatic plants and algae, potentially causing eutrophication and harmful algal blooms. In this study, I identified and characterized different sources of OM in four watersheds of Northeastern Utah with multiple land covers such as cities, forests, and crops. I expected OM in watersheds with human-altered land cover would have more OM produced instream by algae and other primary producers, than OM in less disturbed watersheds, which typically have OM from terrestrial sources. I found that OM at river sites with high human impact had high amounts of OM from instream primary production, but there was also OM produced in-steam at sites with low human impact. The greatest differences in OM across watersheds was due to wastewater treatment effluent. I also measured microbial consumption rates of algal derived and terrestrially derived DOM in experimental streams to quantify how much faster algal derived OM was consumed than terrestrial OM. I found algal derived OM was consumed extremely fast, so fast that realistic measurements of its consumption in some river ecosystems may not be possible. It is important to identify and characterize sources of OM to rivers, so watershed manager scan devise effective OM reduction plans appropriate for the constituent of concern unique to that watershed or region. Constituents of concern associated with OM include pathogens affiliated with manure, toxins in harmful algal blooms, metals, and pharmaceuticals from wastewater treatment effluent. Each pollutant requires a unique mitigation strategy and therefore the first step to pollution mitigation is source identification.
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Gustafsson, Therése. "Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige." Thesis, Linköping University, Department of Thematic Studies, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1422.
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Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering. Because of the important role the root system has to the whole forest ecosystem, it can be of importance to gain knowledge about how roots are affected by external environmental influences.
In the forest ecosystem fertilise the soil has become a common practice in forest management to optimise tree production. Experiments with nitrogen fertilisation have shown that the volume growths of the tree and litter supply have increased after fertilisation. There are also reports about the negative effects nitrogen fertilisation has on decomposition, which results in a decreased decomposition of organic matter.
The aim of this study is to investigate how the decomposition of organic matter, in this case roots, is affected by a large addition of ammonium sulphate. The study concentrates on to statistically evaluate important aspects on how addition of ammonium sulphate affects the decomposition of organic matter below ground in different soil layers and root diameters, and investigate the possibilities that addition of ammonium sulphate could lead to a decreasing potential of carbon mineralisation.
The study was conducted is in Skogaby, which is located in southwest Sweden in the community of Halland. Samplings of roots were made in the experimental area from the humus and mineral layer. Roots used for this study varied from less than 2mm up to 2-5mm. Decomposition of root litters were made with litterbags, which were placed in the soil in the humus and mineral layer in the original place of were the roots were collected. The results from this study showed that there appear significant differences in some of the cases between the control and ammonium sulphate treatments. The conclusion that can be drawn by this study is that the addition of ammonium sulphate, under certain conditions depending on root diameter and soil layer, comes to affect the decomposition of root litter. The addition of ammonium sulphate seems to have a positive effect on the decomposition in the initial phase, for then come to decrease in the later phases and be similar to the control areas. It can also be determined that decomposition does not seem to vary within treatments with regards to root diameter and soil layer. Regarding the question about how carbon mineralisation is affected by addition of ammonium sulphate it is probable that the addition would come to increase the mineralisation in the initial phases of the decomposition, compared with the control plots.
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Erdmann, Svenja [Verfasser]. "The effect of inorganic components on organic matter transformation under hydrothermal conditions : constraints from laboratory experiments studying the abiotic oxidation of n-octane in presence of iron mineral assemblages, additional transition metals and dissolved sulfate / Svenja Erdmann." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2015. http://d-nb.info/1070285196/34.
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Yuan, Chaolei. "Remediation of acid sulfate soils by organic matter addition." Thesis, 2015. http://hdl.handle.net/2440/104712.
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Acid sulfate soils (ASS) are soils containing iron sulfide minerals (predominantly pyrite) and/or their oxidation products. ASS have a large distribution in the world (10⁷−10⁸ ha coastal ASS) and in Australia (215,000 km²). Sulfide in ASS is formed from sulfate in sea water or fresh water under anaerobic conditions by sulfate-reducing bacteria, which need organic matter (OM) as the energy source. Sulfide then reacts with dissolved Fe(II) to form pyrite. Sulfuric material (containing sulfuric acid) is formed during oxidation of ASS with sulfidic material (containing sulfide minerals), resulting in significant release of acid and dissolved metals that can have detrimental effects on soil and water quality and thus ecosystem services. Remediation of sulfuric material and prevention of oxidization of sulfidic material are therefore of great environmental concern. Conventional remedial strategies, such as liming sulfuric material and covering sulfidic material with water or non-ASS soil, can be costly or not practically feasible due to the large amount of lime, water or soil required. Organic matter (OM) is the energy source for sulfate reducers, which play a critical role in the formation of sulfidic material and generate alkalinity during sulfate reduction. OM could influence the oxidation of pyrite through oxygen consumption by OM decomposers, complexation of ferric iron, and coating of pyrite. OM can also buffer acid generated from pyrite oxidation. However, the availability of native OM in ASS can be low due to binding to clay particles, occlusion in aggregates, or complexion by dissolved metals. Therefore application of OM may be an economical and environmentally friendly option to remediate ASS. But systematic studies are required on the effectiveness of OM application for the management of ASS. Ten ASS with sulfuric material, with pH increased to 5.5 and OM (finely ground mature wheat straw) added at 2% (w/w) separately or combined, were incubated submerged for 36 weeks. Unamended soils served as controls. Only the combined treatment (pH increased and OM added) increased the concentration of reduced inorganic sulfur significantly compared to the control and had higher soil pore water pH than the treatment with only pH increased. But the stimulation of sulfate reduction compared to the control of the combined treatment differed among soils which could be attributed to the initial soil properties. Stimulation of sulfate reduction in the combined treatment was negatively correlated with soil clay content and initial nitrate concentration. Clay can limit the availability of the added OM by binding and nitrate is a competing electron acceptor for sulfur reduction. In a subsequent experiment, ASS with smaller increase in sulfate reduction compared with other soils in the previous study were incubated with up to 6% (w/w) OM added for 36 weeks. The concentration of reduced inorganic sulfur increased with OM addition rate, with the increase between 4% and 6% being smaller than that between 2% and 4%, suggesting that besides OM other factors influenced sulfate reduction. Further, the impact of nitrate (competing electron acceptor) at different OM addition rates on sulfate reduction was examined. Nitrate addition inhibited sulfate reduction but the extent was smaller with OM added at 4% compared to 2%, indicating that the inhibition by nitrate was overcome by higher OM addition. In the two following experiments, the effect of OM addition on oxidation and acidification of sulfidic material was investigated by laboratory incubation under oxidizing conditions for 6 weeks. In the first experiment, OM (finely ground mature wheat straw) was added to a sulfidic material at 3% (w/w) as a layer on the soil surface or by mixing into soil. Soil pH decreased by 0.9 unit in the unamended control, increased by 0.2 unit in the treatment with OM as a layer, and increased by 0.8 unit in the treatment with OM mixed into the soil. In the second experiment, 1, 2, 3, and 4% (w/w) OM was mixed into the sulfidic material. The pH decrease was strongest in the unamended control and was smaller with 1% and 2% OM. Only 3% and 4% OM addition prevented acidification. However, the increase in soil sulfate concentration was similar in all the amended treatments. Prevention of acidification of sulfidic material by OM addition can be explained by consumption of oxygen by OM decomposers and pH buffer capacity of OM.Thesis (Ph.D.) (Research by Publication) -- University of Adelaide, School of Agriculture, Food and Wine, 2015.
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Jayalath, Nilmini. "Effect of organic matter and sulfidic clay addition on pH and redox potential of inland acid sulfate soils." Thesis, 2016. http://hdl.handle.net/2440/119516.
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Acid sulfate soils (ASS) are soils or sediments that contain sulfuric, hypersulfidic or hyposulfidic materials or are affected by transformation of sulfidic minerals (e.g., pyritic, FeS2). ASS are widely distributed globally and typical in environments such as coastal and inland wetlands. The main biogeochemical processes influencing the pH in ASS are sulfate reduction and pyrite oxidation. Under flooded conditions (low redox potential), sulfate reducing bacteria (SRB) using easily decomposable organic matter (OM) as their energy source, produce sulfide, which reacts with iron in sediments to form pyrite or mono-sulfides, which are stable under flooded conditions. Sulfate reduction consumes protons and therefore, results in a pH increase. When sulfidic sediments dry, pyrite can oxidise and generates acidity. In soils with low pH buffer capacity (pHBC), this can result in severe acidification and metal solubilisation. Often sulfate reduction does not occur even after pro-longed flooding which may be due to lack of organic carbon (C) availability. Management strategies aiming to ameliorate ASS include liming or inundation. However, they may be uneconomical, unsustainable or can be ineffective. Therefore, alternative strategies are required to manage ASS. OM addition could be an effective strategy to ameliorate ASS due to its role during sulfate reduction. It may also maintain higher level of pH even during dry periods by buffering the acid generated and stimulating microbial activity and thus oxygen consumption through. Readily degradable C of OM and duration, in which OM remain available to sulfate reducing bacteria, may be important in maintaining wetland ASS. Management of wetlands often involves introduction of wet and dry periods to restore ecosystem health. OM addition could be included to improve the effectiveness of this strategy. In this thesis, soils from Banrock station wetland were used in a series of incubation experiments. The wetland has extensive ASS and acidification was observed in many areas in a survey conducted in 2009. Since then, wetland managers have introduced wet-dry cycles to improve wetland health. The aim of this thesis was to determine the effect of type of organic C or sulfidic clay soils added on pH and redox potential (Eh) in ASS during wet and dry periods. The hypotheses to be tested were: (¡) Addition of easily decomposable OM will have a greater effect on pH and redox potential than poorly decomposable OM (¡¡) Acidification during the dry period will be smaller at high compared to low water content because high water content limits diffusion of oxygen (¡¡¡) Mixing sulfidic clay soils into ASS will minimise pH changes during wet and dry periods, particularly clay soils with high pH buffer capacity. In the first experiment, the effect of type of organic amendment was investigated. Three wetland ASS (sulfuric, hypersulfidic and hyposulfidic) collected from different depths were used. The soils, unamended or amended with 10 g C kg-1 as glucose, wheat straw, pea straw or Phragmites litter, were incubated for 18 weeks under flooded conditions (“wet period”) followed by 10 weeks during which the soils were maintained at 100% of maximum water-holding capacity (WHC) (“dry period”). During the wet period, the pH decreased in the control and with glucose to pH 3-4, but increased or was maintained in residueamended soils (pH at the end of the wet period about 7). In the dry period, the pH of the control and glucose amended soils remained low, whereas the pH in residue amended soils decreased. However, at end of the dry period, the pH was higher in residue amended soils than in the control or glucose amended soils, particularly with pea straw (carbon: nitrogen 50, C/N 50). It can be concluded that amendment of ASS with plant residues (particularly those with low to moderate C/N ratio) can stimulate pH increase during flooding and reduce acidification under oxidizing conditions. The second experiment was carried out to assess the effect of OM addition on pH in a wet-dry cycle followed by a second wet period. A further aim was to investigate the influence of water content during the dry period on acidification. Three ASS (sulfuric, hypersulfidic and hyposulfidic) were collected from one profile and unamended or amended with 10 g C kg-1 as finely ground wheat straw. The soils were exposed to a submerged (wet) period, a dry period, followed by another wet period. In the first wet period (10 weeks), the pH increased only in the amended soils, which was accompanied by a strong decrease in Eh. To investigate the effect of water content during the dry period on pH, the soils were rapidly dried to 40, 60, 80 or 100% of WHC at the start of the dry period. This water content was maintained during the dry period. The pH decrease during the 10-week dry period was greater in amended than in unamended soils and greater at 60, 80 or 100% than at 40% of WHC. At the end of the dry period, the pH was higher in amended than in unamended soils and higher at 40% of WHC than at the higher water contents. In the second wet period (16 weeks), the pH increased only in the amended soils. The pH increase was accompanied by a decrease in Eh in the amended soils. The water content in the previous dry period did not influence pH in the second wet period in the unamended soils, but in the amended soils, the pH was higher in soils previously maintained at 40% of WHC than that maintained at higher water contents. At the end of the second wet period, the pH was higher in amended than in unamended soils. This study shows the ameliorative effect of OM addition in ASS. OM addition can improve energy supply for sulfate reducers which results in an increase in pH during the wet period and lead to a higher pH in the oxidation period. The smaller pH increase and Eh decrease in amended soils in the second compared to the first wet period suggests that OM decomposition was lower in the second wet period likely because rapidly decomposable compounds had been utilised in the previous wet and dry periods and only recalcitrant OM remained. Therefore OM may have to be added repeatedly for sustained amelioration of ASS. The aim of the third experiment was to investigate the effect of addition of hyposulfidic clay soils to a sufuric sandy soil on pH changes in reduced and oxidised conditions. A sulfuric sandy soil (pH 4.1) was mixed with three hyposulfidic clay soils (with clay contents ranging between 38 and 72%) to give clay soil proportions of 0, 25, 50, 75 and 100 (% dry soil). According to their net negative acidity, the three clay soils are referred to as: NA-334, NA-54 and NA-8 (values in moles H+ tonne-). The soils were amended with wheat straw at 10 g of C kg -1 and then incubated for 14 weeks under reducing conditions (wet period) followed by 11 weeks incubation under oxidising conditions (dry period) during which they were maintained at 100% of maximum WHC. The pH of the sulfuric soil alone increased during the wet period by about two pH units (to pH 6) and decreased by more than two pH units (to pH <4) during the dry period. In the clay soils alone and treatments with sulfuric soil, the pH during the wet period decreased by 0.5 to 1 unit with NA-334 and NA-54 and increased by one unit with NA-8. The pH was >6 in all clay treatments at the end of the wet period. During the dry period, the pH remained above pH 7 with NA-334 and decreased by about one unit (to pH 5.5) with NA-8. In treatments with NA-54, the pH decrease during the dry period depended on the proportion of clay soil, ranging from 0.5 pH unit with 75% clay soil to two pH units with 25% clay soil. The capacity of the clay soil treatments to maintain stable pH during wet and dry periods depended mainly on the negative net acidity of the added clay soils, but was not related to their concentration of reduced inorganic sulfur or clay content. It can be concluded that addition of clay soils with high negative net acidity could be used to ameliorate acidity in ASS. The fourth experiment was conducted to determine the effect of OM addition over two successive wet-dry cycles in four ASS. Four soils differing in clay content (10, 15, 23, 38% referred to as C10, C15, C23 and C38) were unamended or amended with 10 g C kg-1 finely ground wheat straw and incubated over 24 weeks with each wet and each dry period lasting 6 weeks. Soil pH increased in both wet periods, particularly in amended soils with low clay content (C10 and C15). The Eh decreased more strongly in amended soils than in unamended soils and became negative from week 2 onwards whereas the Eh stayed positive in unamended soils except C38. In the dry periods, the pH decreased more strongly in amended soils than in unamended soils, particularly in C10 and C15. Changes in pH during wet and dry periods were greater in soils with low clay content (C10, C15) than those with high clay content (C23, C38). The effect of wheat straw addition on pH at the end of wet and dry periods did not differ between the two wet-dry periods, with a higher pH in amended than unamended soils. This study showed that wheat straw addition maintains its ameliorative effect on soil pH for at least two wet-dry cycles, but the pH effect depends on clay content, being greater in soils with low clay content. The effectiveness of this method would have to be tested under field conditions, particularly where wet and dry periods continue for longer periods.Thesis (Ph.D.) (Research by Publication) -- University of Adelaide, School of Agriculture, Food and Wine, 2016.
Books on the topic "Organic matter addition"
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Kirchman, David L. Degradation of organic matter. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198789406.003.0007.
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The aerobic oxidation of organic material by microbes is the focus of this chapter. Microbes account for about 50% of primary production in the biosphere, but they probably account for more than 50% of organic material oxidization and respiration (oxygen use). The traditional role of microbes is to degrade organic material and to release plant nutrients such as phosphate and ammonium as well as carbon dioxide. Microbes are responsible for more than half of soil respiration, while size fractionation experiments show that bacteria are also responsible for about half of respiration in aquatic habitats. In soils, both fungi and bacteria are important, with relative abundances and activity varying with soil type. In contrast, fungi are not common in the oceans and lakes, where they are out-competed by bacteria with their small cell size. Dead organic material, detritus, used by microbes, comes from dead plants and waste products from herbivores. It and associated microbes can be eaten by many eukaryotic organisms, forming a detritus food web. These large organisms also break up detritus into small pieces, creating more surface area on which microbes can act. Microbes in turn need to use extracellular enzymes to hydrolyze large molecular weight compounds, which releases small compounds that can be transported into cells. Fungi and bacteria use a different mechanism, “oxidative decomposition,” to degrade lignin. Organic compounds that are otherwise easily degraded (“labile”) may resist decomposition if absorbed to surfaces or surrounded by refractory organic material. Addition of labile compounds can stimulate or “prime” the degradation of other organic material. Microbes also produce organic compounds, some eventually resisting degradation for thousands of years, and contributing substantially to soil organic material in terrestrial environments and dissolved organic material in aquatic ones. The relationship between community diversity and a biochemical process depends on the metabolic redundancy among members of the microbial community. This redundancy may provide “ecological insurance” and ensure the continuation of key biogeochemical processes when environmental conditions change.
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Nanny, Mark A., Roger A. Minear, and Jerry A. Leenheer, eds. Nuclear Magnetic Resonance Spectroscopy in Environment Chemistry. Oxford University Press, 1997. http://dx.doi.org/10.1093/oso/9780195097511.001.0001.
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This book demonstrates the usefulness of NMR spectroscopy for a wide variety of applications in environmental science and technology. It contains a wealth of information relating to instrumentation, sample preparation, and data interpretation. The book is divided into three sections discussing contaminant interaction, solution and condensed-phase characterization, and nutrients and natural organic matter characterization. In addition to these in-depth chapters, an introductory overview provides the basic principles of solution and solid-state NMR spectroscopy. Each section also contains a discussion of advances in each area directly attributable to NMR spectroscopy. A final chapter suggests future directions for the deployment of this powerful technology in environmental science.
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Patterson, DJ, and MA Burford. Guide to Protozoa of Marine Aquaculture Ponds. CSIRO Publishing, 2001. http://dx.doi.org/10.1071/9780643101081.
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As well as being a culture environment for fish and crustaceans, an aquaculture pond is a rich and complex ecosystem that is dominated by the microbial community. The community is nourished by food and sunlight, and is made up of algae, bacteria and, importantly, protozoa. Protozoa live by eating other organisms and detritus, or by absorbing soluble organic matter dissolved in the water. Ultimately they affect water quality in aquaculture ponds, including the stability of algal and bacterial communities, and nutrient concentrations. In addition, some protozoa can have adverse effects on the health of cultured species.
Guide to Protozoa of Marine Aquaculture Ponds is designed to provide a simple means of identifying the main groups of protozoa found in aquaculture ponds through the use of photographs and drawings. This is supplemented with information on the likely effects of protozoa on water quality and the health of the cultured species.
This guide is an indispensable tool for those involved in rearing marine animals, as well as aquaculture researchers and teachers.
Please note that this book is spiral-bound.
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Schulenberg, David. Bach. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190936303.001.0001.
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Bach is an entirely new volume in the “Master Musicians” series, replacing the old entry by Malcolm Boyd with updated coverage of the composer’s life and works. Tracing the composer’s biography from origins in Thuringia to mastery as cantor and music director at Leipzig, the book sets Bach in the cultural context of early modern Europe. Family life, social structure, and court culture are among the topics examined from the perspective of contemporary approaches to history. Bach’s work as student, organist, music director, and teacher is considered alongside his compositions, with discussions of representative examples from all the major categories, including concertos, cantatas, chamber music, and pieces for harpsichord and for organ. In addition to a handy list of works and other useful reference matter included in every volume of the series, this book is also accompanied by an online supplement that offers a glossary, a guide to further reading, and audio versions of the numerous music examples.
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Wijdicks, Eelco F. M. Beliefs and Brain Death. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190662493.003.0004.
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Globalization has increased cultural diversity in many communities. This has immediate implications for care of patients with catastrophic neurological injury and later discussions of brain death and organ donation. While the major religions in the United States—Christianity, Islam, and Judaism—have taken a tolerant position in these matters, some denominations within them are vigorously opposed to it. This chapter presents a range of cultural and religious views of brain death determination and organ donation. In addition to the three major religions, Buddhist and native American views regarding brain death determination as well as organ donation are discussed. Conflict resolution over organ donation is discussed along with the role of clergy in mediating such conflicts between families and medical staff.
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Brown, Abbe, Smita Kheria, Jane Cornwell, and Marta Iljadica. Contemporary Intellectual Property. Oxford University Press, 2019. http://dx.doi.org/10.1093/he/9780198799801.001.0001.
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Contemporary Intellectual Property: Law and Policy, fifth edition, offers a unique perspective on intellectual property (IP) law, unrivalled amongst IP textbooks. An accessible introduction to IP law, it provides not only a comprehensive account of the substantive law, but also discusses the overarching policies directing the legal decision-making, as well as areas for further debate. Intellectual property law is an increasingly global subject, and the book introduces the relevant European and international dimensions to present a realistic view of the law as it actually operates. It explores IP law as an organic discipline, evaluating the success with which it has responded to new challenges. Images and diagrams, with analysis of key cases and key extracts, are all incorporated alongside the author commentary to clearly illustrate the core principles in IP law. Exercise, questions, and discussion points are provided to help the reader to engage with the material, and additional material is provided in the Online Resources. Beyond providing an up-to-date account of IP law, the text examines the complex policies that inform modern IP law at the domestic (including Scottish), European, and international levels, giving the reader a true insight into the discipline and the shape of things to come. The focus is on contemporary challenges to IP law and policy, and the reader is encouraged to engage critically with the text and the subject matter. The book has been carefully developed to ensure that the complexities of the subject are addressed in a clear and approachable way.
Book chapters on the topic "Organic matter addition"
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Alexandrova, G. P., G. Dolmaab, Sh Tserenpil, L. A. Grishenko, B. G. Sukhov, D. Regdel, and B. A. Trofimov. "A New Humic Acid Preparation with Addition of Silver Nanoparticles." In Functions of Natural Organic Matter in Changing Environment, 783–88. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-5634-2_142.
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Liu, Yong, Xiongsheng Yu, Fangbai Li, and Jianming Xu. "Link Between Acetate Extractable Fe(II) Accumulation and Pentachlorophenol Dissipation in Flooded Paddy Soils with Vicia cracca L. Addition." In Functions of Natural Organic Matter in Changing Environment, 691–94. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-5634-2_125.
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Schäfer, A. I., A. G. Fane, and T. D. Waite. "Chemical Addition Prior to Membrane Processes for Natural Organic Matter (NOM) Removal." In Chemical Water and Wastewater Treatment V, 125–37. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/978-3-642-72279-0_11.
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Shchegolikhina, Anastasia, and Bernd Marschner. "Effects of Cation Saturation, Substrate Addition, and Aging on the Mineralization and Formation of Non-extractable Residues of Nonylphenol and Phenanthrene in a Sandy Soil." In Functions of Natural Organic Matter in Changing Environment, 673–77. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-5634-2_122.
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Dou, Sen, Song Guan, Guang Chen, and Gang Wang. "Dynamics of Newly Formed Humic Acid and Fulvic Acid in Aggregates After Addition of the 14C-Labelled Wheat Straw in a Typic Hapludoll of Northeast China." In Functions of Natural Organic Matter in Changing Environment, 31–36. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-5634-2_6.
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Houot, Sabine, Enrique Barriuso, and Valérie Bergheaud. "Modification of Herbicide Mineralization and Extractability in Soil by Addition of Organic Matter in Model Experiments." In Effect of Mineral-Organic-Microorganism Interactions on Soil and Freshwater Environments, 237–45. Boston, MA: Springer US, 1999. http://dx.doi.org/10.1007/978-1-4615-4683-2_26.
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Stouvenakers, Gilles, Peter Dapprich, Sebastien Massart, and M. Haïssam Jijakli. "Plant Pathogens and Control Strategies in Aquaponics." In Aquaponics Food Production Systems, 353–78. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-15943-6_14.
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AbstractAmong the diversity of plant diseases occurring in aquaponics, soil-borne pathogens, such as Fusarium spp., Phytophthora spp. and Pythium spp., are the most problematic due to their preference for humid/aquatic environment conditions. Phytophthora spp. and Pythium spp. which belong to the Oomycetes pseudo-fungi require special attention because of their mobile form of dispersion, the so-called zoospores that can move freely and actively in liquid water. In coupled aquaponics, curative methods are still limited because of the possible toxicity of pesticides and chemical agents for fish and beneficial bacteria (e.g. nitrifying bacteria of the biofilter). Furthermore, the development of biocontrol agents for aquaponic use is still at its beginning. Consequently, ways to control the initial infection and the progression of a disease are mainly based on preventive actions and water physical treatments. However, suppressive action (suppression) could happen in aquaponic environment considering recent papers and the suppressive activity already highlighted in hydroponics. In addition, aquaponic water contains organic matter that could promote establishment and growth of heterotrophic bacteria in the system or even improve plant growth and viability directly. With regards to organic hydroponics (i.e. use of organic fertilisation and organic plant media), these bacteria could act as antagonist agents or as plant defence elicitors to protect plants from diseases. In the future, research on the disease suppressive ability of the aquaponic biotope must be increased, as well as isolation, characterisation and formulation of microbial plant pathogen antagonists. Finally, a good knowledge in the rapid identification of pathogens, combined with control methods and diseases monitoring, as recommended in integrated plant pest management, is the key to an efficient control of plant diseases in aquaponics.
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Franzen, David W., Keith Goulding, Antonio P. Mallarino, and Michael J. Bell. "How Closely Is Potassium Mass Balance Related to Soil Test Changes?" In Improving Potassium Recommendations for Agricultural Crops, 263–82. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_10.
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AbstractThe exchangeable fraction of soil potassium (K) has been viewed as the most important source of plant-available K, with other sources playing smaller roles that do not influence the predictive value of a soil test. Thus, as K mass balance changes, the soil test should change correspondingly to be associated with greater or reduced plant availability. However, soil test changes and the availability of K to plants are influenced by many other factors. This chapter reviews research on soil test K changes and the relation to crop uptake and yield. A mass-balance relationship is rarely achieved from the measurement of exchangeable K because of the potential for buffering of K removal from structural K in feldspars and from interlayer K in primary and secondary layer silicates. Similarly, surplus K additions can be fixed in interlayer positions in secondary layer silicates, or potentially sequestered in sparingly soluble neoformed secondary minerals, neither of which is measured as exchangeable K. In addition, soil moisture, temporal differences in exchangeable K with K uptake by crops, K leaching from residues, clay type, organic matter contribution to the soil CEC, and type of K amendment confound attempts to relate K additions and losses with an exchangeable K soil test. Research is needed to create regionally specific K soil test procedures that can predict crop response for a subset of clays and K-bearing minerals within specific cropping systems.
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Hinsinger, Philippe, Michael J. Bell, John L. Kovar, and Philip J. White. "Rhizosphere Processes and Root Traits Determining the Acquisition of Soil Potassium." In Improving Potassium Recommendations for Agricultural Crops, 99–117. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_4.
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AbstractPlants acquire K+ ions from the soil solution, and this small and dynamic pool needs to be quickly replenished via desorption of surface-adsorbed K from clay minerals and organic matter, by release of interlayer K from micaceous clay minerals and micas, or structural K from feldspars. Because of these chemical interactions with soil solid phases, solution K+ concentration is kept low and its mobility is restricted. In response, plants have evolved efficient strategies of root foraging. Root traits related to root system architecture (root angle and branching), root length and growth, together with root hairs and mycorrhiza-related traits help to determine the capacity of plants to cope with the poor mobility of soil K. Rooting depth is also important, given the potentially significant contribution of subsoil K in many soils. Root-induced depletion of K+ shifts the exchange equilibria, enhancing desorption of K, as well as the release of nonexchangeable, interlayer K from minerals in the rhizosphere. Both these pools can be bioavailable if plant roots can take up significant amounts of K at low concentrations in the soil solution (in the micromolar range). In addition, roots can significantly acidify their environment or release large amounts of organic compounds (exudates). These two processes ultimately promote the dissolution of micas and feldspars in the rhizosphere, contributing to the mining strategy evolved by plants. There are thus several root or rhizosphere-related traits (morphological, physiological, or biochemical) that determine the acquisition of K by crop species and genotypes.
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Zaman, M., K. Kleineidam, L. Bakken, J. Berendt, C. Bracken, K. Butterbach-Bahl, Z. Cai, et al. "Greenhouse Gases from Agriculture." In Measuring Emission of Agricultural Greenhouse Gases and Developing Mitigation Options using Nuclear and Related Techniques, 1–10. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-55396-8_1.
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AbstractThe rapidly changing global climate due to increased emission of anthropogenic greenhouse gases (GHGs) is leading to an increased occurrence of extreme weather events such as droughts, floods, and heatwaves. The three major GHGs are carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). The major natural sources of CO2 include ocean–atmosphere exchange, respiration of animals, soils (microbial respiration) and plants, and volcanic eruption; while the anthropogenic sources include burning of fossil fuel (coal, natural gas, and oil), deforestation, and the cultivation of land that increases the decomposition of soil organic matter and crop and animal residues. Natural sources of CH4 emission include wetlands, termite activities, and oceans. Paddy fields used for rice production, livestock production systems (enteric emission from ruminants), landfills, and the production and use of fossil fuels are the main anthropogenic sources of CH4. Nitrous oxide, in addition to being a major GHG, is also an ozone-depleting gas. N2O is emitted by natural processes from oceans and terrestrial ecosystems. Anthropogenic N2O emissions occur mostly through agricultural and other land-use activities and are associated with the intensification of agricultural and other human activities such as increased use of synthetic fertiliser (119.4 million tonnes of N worldwide in 2019), inefficient use of irrigation water, deposition of animal excreta (urine and dung) from grazing animals, excessive and inefficient application of farm effluents and animal manure to croplands and pastures, and management practices that enhance soil organic N mineralisation and C decomposition. Agriculture could act as a source and a sink of GHGs. Besides direct sources, GHGs also come from various indirect sources, including upstream and downstream emissions in agricultural systems and ammonia (NH3) deposition from fertiliser and animal manure.
Conference papers on the topic "Organic matter addition"
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Philben, Michael, Jianqiu Zheng, David Graham, Markus Bill, Jeff Heikoop, Stan Wullschleger, and Baohua Gu. "STIMULATION OF ANAEROBIC ORGANIC MATTER DEGRADATION BY NITROGEN ADDITION IN TUNDRA SOILS." In 67th Annual Southeastern GSA Section Meeting - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018se-312500.
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Wang, Yu, Rui Xie, Qi Chen, Ruanhong Cai, Chen He, Weidong Guo, Quan Shi, Nianzhi Jiao, and Qiang Zheng. "Linking Microbial Population Succession and DOM Molecular Transformation in Synechococcus-Derived Organic Matter Addition Incubations." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.2794.
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Moldoveanu, Aurelia�Manuela. "THE�DYNAMICS�OF�MARINE�BACTERIONEUSTON��IN�LABORATORY�MICROCOSMS:�2.�THE�INFLUENCE�OF�ORGANIC�MATTER�ADDITION." In SGEM2012 12th International Multidisciplinary Scientific GeoConference and EXPO. Stef92 Technology, 2012. http://dx.doi.org/10.5593/sgem2012/s14.v3011.
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M.R. Burchell II, R.W. Skaggs, S.W. Broome, and and C.R. Lee. "Effect of Substrate Organic Matter Addition on Nitrate Removal Efficiency in Surface-Flow Constructed Wetlands." In 2002 Chicago, IL July 28-31, 2002. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2002. http://dx.doi.org/10.13031/2013.9835.
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Burchell, M. R., R. W. Skaggs, R. O. Evans, C. R. Lee, and S. W. Broome. "Addition of Organic Matter to Agricultural Ditch Soils to be Used as Constructed Wetlands for Nitrate Treatment." In World Environmental and Water Resources Congress 2007. Reston, VA: American Society of Civil Engineers, 2007. http://dx.doi.org/10.1061/40927(243)233.
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Katithi, David M., and David O. Opar. "Petroleum Geochemistry of the Loperot-1 Well in Lokichar Basin, Kenya." In SPE/AAPG Africa Energy and Technology Conference. SPE, 2016. http://dx.doi.org/10.2118/afrc-2557372-ms.
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ABSTRACT The work reports an in-depth review of bulk and molecular geochemical data to determine the organic richness, kerogen type and thermal maturity of the Lokhone and the stratigraphically deeper Loperot shales of the Lokichar basin encountered in the Loperot-1 well. Oil-source rock correlation was also done to determine the source rocks’ likelihood as the source of oil samples obtained from the well. A combination of literature and geochemical data analyses show that both shales have good to excellent potential in terms of organic and hydrogen richness to act as conventional petroleum source rocks. The Lokhone shales have TOC values of 1.2% to 17.0% (average 5.16%) and are predominantly type I/II organic matter with HI values in the range of 116.3 – 897.2 mg/g TOC. The Lokhone source rocks were deposited in a lacustrine depositional environment in episodically oxic-dysoxic bottom waters with periodic anoxic conditions and have Tmax values in addition to biomarker signatures typical of organic matter in the mid-mature to mature stage with respect to hydrocarbon generation and immature for gas generation with Ro values of 0.51 – 0.64%. The Loperot shales were shown to be possibly highly mature type II/III source rocks with TOC values of 0.98% – 3.18% (average 2.4%), HI of 87 – 115 mg/g TOC and Ro of 1.16 – 1.33%. The Lokhone shale correlate well with the Loperot-1 well oils and hence is proposed as the principal source rock for the oils in the Lokichar basin. Although both source rocks have good organic richness to act as shale gas plays, they are insufficiently mature to act as shale gas targets but this does not preclude their potential deeper in the basin where sufficient gas window maturities might have been attained. The Lokhone shales provide a prospective shale oil play if the reservoir suitability to hydraulic fracturing can be defined. A basin wide study of the source rocks thickness, potential, maturation and expulsion histories in the Lokichar basin is recommended to better understand the present-day distribution of petroleum in the basin.
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Jun Zhu, Zhijian Zhang, and Curtis Miller. "Performance of a Lab-Scale Sequencing Batch Reactor with Addition of Carbon in Removing Nutrient and Organic Matter in Liquid Swine Manure." In 2005 Tampa, FL July 17-20, 2005. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2005. http://dx.doi.org/10.13031/2013.18949.
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Mikhalev, E. V., and D. D. Khilov. "INFLUENCE OF VARIOUS TYPES OF ORGANIC WASTE OF AGROINDUSTRIAL COMPLEX ON PRODUCTIVITY OF ROW CROPS IN THE CONDITIONS OF THE NIZHNY NOVGOROD REGION." In STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS Volume 2. DSTU-Print, 2020. http://dx.doi.org/10.23947/interagro.2020.2.494-497.
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The introduction of unprocessed organic waste into the soil leads to the accumulation of nutrition elements for their subsequent assimilation by plants in the land-use system from the organomineral complexes of the soil, which will significantly increase the yield of agricultural crops. However, for 2- 3 years with constant introduction of "raw" manure, soil degradation occurs. So, with the constant introduction of "fresh" litter will be the oppression of cultivated plants by "osmosis" and the subsequent destruction of their root rot due to its high content of raw litter of pathogenic organisms and high level of Pro-infectious potential, which reduces fungistasis soil, leading to lower yields. The cardinal way out of this situation is to add composted manure to the soil. In addition to increasing the content of organic matter in the soil, including humus. Due to this, there is a decrease in osmosis and phytopathogenic load. The biological activity of the soil when composting will be slightly lower than when applying " raw " manure. However, due to this fact, in the following years, when using complex compost, the soil will contain more organic matter compared to the control. In addition," full "composting reduces "osmosis", kills weed seeds and destroys potentially dangerous pathogens of agricultural crops. Based on the above, it can be assumed that the introduction of new organic fertilizers should have a multi-sided effect on the agronomic properties of the soil, which in the end, with the correct use of complex compost, dramatically increases the yield of crops, including cereals.
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Tagawa, Akihiro, and Masahisa Watanabe. "Demonstration Test Results of Organic Materials’ Volumetric Reduction Using Bio-Ethanol, Thermal Decomposition and Burning." In ASME 2013 15th International Conference on Environmental Remediation and Radioactive Waste Management. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icem2013-96133.
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To discover technologies that can be utilized for decontamination work and verify their effects, economic feasibility, safety, and other factors, the Ministry of the Environment launched the “FY2011 Decontamination Technology Demonstrations Project” to publicly solicit decontamination technologies that would be verified in demonstration tests and adopted 22 candidates. JAEA was commissioned by the Ministry of the Environment to provide technical assistance related to these demonstrations. This paper describes the volume reduction due to bio-ethanol, thermal decomposition and burning of organic materials in this report. The purpose of this study is that to evaluate a technique that can be used as biomass energy source, while performing volume reduction of contamination organic matter generated by decontamination. An important point of volume reduction technology of contaminated organic matter, is to evaluate the mass balance in the system. Then, confirming the mass balance of radioactive material and where to stay is important. The things that are common to all technologies, are ensuring that the radioactive cesium is not released as exhaust gas, etc.. In addition, it evaluates the cost balance and energy balance in order to understand the applicability to the decontamination of volume reduction technology. The radioactive cesium remains in the carbides when organic materials are carbonized, and radioactive cesium does not transfer to bio-ethanol when organic materials are processed for bio-ethanol production. While plant operating costs are greater if radioactive materials need to be treated, if income is expected by business such as power generation, depreciation may be calculated over approximately 15 years.
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Martin, Richard J., and Jeff D. Colwell. "De Novo VOC From Regenerative Thermal Oxidizers." In ASME 2003 Heat Transfer Summer Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ht2003-47557.
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Regenerative thermal oxidizers are used extensively for the abatement of volatile organic compound (VOC) emissions from process vent streams. Due to the unique heat storage and convection properties of the ceramic packing utilized, they are especially well suited for applications with high flows and dilute concentrations of organic vapors. However, packed-bed devices such as these are known to be vulnerable to interstitial plugging when processing vent streams that contain particulate matter in addition to the VOC. In this paper, the authors postulate a new failure mode that involves relatively small concentrations of organic solids in the vent stream, and that may lead to serious performance deficiencies long before interstitial plugging becomes problematic. Specifically, we assert that “De Novo VOC” can be generated from organic particulate matter that adheres temporarily to the bed and is revaporized when the flow is reversed, causing a significant decrease in the apparent destruction efficiency of the abatement device. In this theoretical treatment, the spatial and temporal response of a hypothetical thermal bed is compared against the phase-change and combustion characteristics of a common organic solid, in order to estimate particle loading levels that may pose immediate compliance problems for users of these systems. Although experimental data are not available to corroborate the conclusions reached herein, the authors contend that routine carryover of small amounts of organic particles from a collection device (e.g., baghouse) to the thermal destruction system can create high exhaust VOC levels, and may eventually lead to hostile fires in the beds. As a means of mitigating against such failures, the authors recommend that an inlet particulate loading limit be implemented for all regenerative thermal oxidizer installations.
Reports on the topic "Organic matter addition"
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Ardakani, O. H. Organic petrography and thermal maturity of the Paskapoo Formation in the Fox Creek area, west-central Alberta. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330296.
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The Paskapoo Formation, which ranges in age from middle to upper Paleocene, is the major shallow aquifer in Alberta. This study is part of a larger GSC-led study on the potential environmental impact of hydrocarbon development in the Fox Creek area (west-central Alberta) on shallow aquifers. Fox Creek is located near the northern limit of the Paskapoo Formation. In addition to the underlying organic-rich source rocks in the study area, including the Duvernay Formation that is currently exploited for hydrocarbon resources, the Paskapoo Formation contains organic-rich intervals and coal seams. In order to investigate any potential internal hydrocarbon sources within the Paskapoo Formation, ninety-seven (97) cutting samples from the formation obtained from eight shallow monitoring wells (50-90 m) in the study area were studied for total organic carbon (TOC) content, organic matter composition and thermal maturity of coal seams using programmed pyrolysis analysis and organic petrography. The TOC content of all samples ranges from 0.2 to 8.8 wt. %, with a mean value of 0.95 ± 1.6 wt. % (n=97). The Tmax values of studied samples range from 347 to 463 °C, with a mean value of 434 ± 20 °C that suggest a range of thermal maturity from immature to peak oil window. The random reflectance (Rr) measurement and fluorescence microscopy on eighteen (18) selected samples with TOC content &gt; ~1 wt. % shows a mean Rr value of 0.27% and 0.42% for the overlying till deposits and the underlying shallow depth sandstone, siltstone, shale and coal seams respectively, indicating a low rank coal ranging from lignite to sub-bituminous coal. Blue to green and yellow fluorescing liptinite macerals further confirmed the low maturity of studied samples. The low S2 yield of a large part of the samples (65%) resulted in unreliable Tmax values that overestimated the thermal maturity. Although the organic matter in the studied intervals are immature, exsudatinite, as secondary liptinite maceral, was observed in samples from the lower parts of the studied monitoring wells. Exsudatinite generally derives from the transformation of sporinite, alginite, resinite and varieties of vitrinite, which is a resinous or asphalt like material. Considering the thickness and distribution of coal seams in the studied samples, it is unlikely the exsudatinite will be a major source for aquifer hydrocarbon contamination in the study area. Additional stratigraphic studies and molecular geochemical analysis could provide an estimate of the total volume of possible organic compounds contribution to the aquifer in the study area. Due to the presence of coal seams in the studied intervals of the Paskapoo Formation, it is important to investigate the possibility of biogenic methane formation in Paskapoo shallow aquifers.
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Avnimelech, Yoram, Richard C. Stehouwer, and Jon Chorover. Use of Composted Waste Materials for Enhanced Ca Migration and Exchange in Sodic Soils and Acidic Minespoils. United States Department of Agriculture, June 2001. http://dx.doi.org/10.32747/2001.7575291.bard.
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Restoration of degraded lands and the development of beneficial uses for waste products are important challenges facing our society. In addition there is a need to find useful and environmentally friendly applications for the organic fractions of municipal and other solid waste. Recent studies have shown that composted wastes combined with gypsum or gypsum-containing flue gas desulfurization by-products enhance restoration of sodic soils and acidic minespoils. The mechanism by which this synergistic effect occurs in systems at opposite pH extremes appears to involve enhanced Ca migration and exchange. Our original research objectives were to (1) identify and quantify the active compost components involved in Ca transport, (2) determine the relative affinity of the compost components for Ca and competing metals in the two soil/spoil systems, (3) determine the efficacy of the compost components in Ca transport to subjacent soil and subsequent exchange with native soil cations, and (4) assess the impacts of compost enhanced Ca transport on soil properties and plant growth. Acidic mine spoils: During the course of the project the focus for objective (1) and (2) shifted more towards developing and evaluating methods to appropriately quantify Ca2+ and Al3+ binding to compost derived dissolved organic matter (DOM). It could be shown that calcium complexation by sewage sludge compost derived DOM did not significantly change during the composting process. A method for studying Al3+ binding to DOM was successfully developed and should allow future insight into DOM-Al3+ interactions in general. Laboratory column experiments as well as greenhouse experiments showed that in very acidic mine spoil material mineral dissolution controls solution Al3+ concentration as opposed to exchange with Ca2+. Therefore compost appeared to have no effect on Al3+ and Ca2+ mobility and did not affect subsoil acidity. Sodic alkaline soils: Batch experiments with Na+ saturated cation exchange resins as a model for sodic soils showed that compost home cations exchanged readily with Na+. Unlike filtered compost extracts, unfiltered compost suspensions also significantly increased Ca2+ release from CaCO3. Soil lysimeter experiments demonstrated a clear impact of compost on structural improvement in sodic alkaline soils. Young compost had faster, clearer and longer lasting effects on soil physical and chemical properties than mature compost. Even after 2 growing seasons differences could still be observed. Compost increased Ca2+ concentration in soil solution and solubility of pedogenic CaCO3 that is highly insoluble under alkaline conditions. The solubilized Ca2+ efficiently exchanged Na+ in the compost treated soils and thus greatly improved the soil structure.
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Litaor, Iggy, James Ippolito, Iris Zohar, and Michael Massey. Phosphorus capture recycling and utilization for sustainable agriculture using Al/organic composite water treatment residuals. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600037.bard.
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Objectives: 1) develop a thorough understanding of the sorption mechanisms of Pi and Po onto the Al/O- WTR; 2) determine the breakthrough range of the composite Al/O-WTR during P capturing from agro- wastewaters; and 3) critically evaluate the performance of the composite Al/O-WTR as a fertilizer using selected plants grown in lysimeters and test-field studies. Instead of lysimeters we used pots (Israel) and one- liter cone-tainers (USA). We conducted one field study but in spite of major pretreatments the soils still exhibited high enough P from previous experiments so no differences between control and P additions were noticeable. Due to time constrains the field study was discontinued. Background: Phosphorous, a non-renewable resource, has been applied extensively in fields to increase crop yield, yet consequently has increased the potential of waterway eutrophication. Our proposal impetus is the need to develop an innovative method of P capturing, recycling and reuse that will sustain agricultural productivity while concurrently reducing the level of P discharge from and to agricultural settings. Major Conclusions & Achievements: An innovative approach was developed for P removal from soil leachate, dairy wastewater (Israel), and swine effluents (USA) using Al-based water treatment residuals (Al- WTR) to create an organic-Al-WTR composite (Al/O-WTR), potentially capable of serving as a P fertilizer source. The Al-WTR removed 95% inorganic-P, 80% to 99.9% organic P, and over 60% dissolved organic carbon from the agro-industrial waste streams. Organic C accumulation on particles surfaces possibly enhanced weak P bonding and facilitated P desorption. Analysis by scanning electron microscope (SEM- EDS), indicated that P was sparsely sorbed on both calcic and Al (hydr)oxide surfaces. Sorption of P onto WW-Al/O-WTR was reversible due to weak Ca-P and Al-P bonds induced by the slight alkaline nature and in the presence of organic moieties. Synchrotron-based microfocused X-ray fluorescence (micro-XRF) spectrometry, bulk P K-edge X-ray absorption near edge structure spectroscopy (XANES), and P K-edge micro-XANES spectroscopy indicated that adsorption was the primary P retention mechanism in the Al- WTR materials. However, distinct apatite- or octocalciumphosphatelike P grains were also observed. Synchrotron micro-XRF mapping further suggested that exposure of the aggregate exteriors to wastewater caused P to diffuse into the porous Al-WTR aggregates. Organic P species were not explicitly identified via P K-edge XANES despite high organic matter content, suggesting that organic P may have been predominantly associated with mineral surfaces. In screen houses experiments (Israel) we showed that the highest additions of Al/O-WTR (5 and 7 g kg⁻¹) produced the highest lettuce (Lactuca sativa L. var. longifolial) yield. Lettuce yield and P concentration were similar across treatments, indicating that Al/O- WTR can provide sufficient P to perform similarly to common fertilizers. A greenhouse study (USA) was utilized to compare increasing rates of swine wastewater derived Al/O-WTR and inorganic P fertilizer (both applied at 33.6, 67.3, and 134.5 kg P₂O₅ ha⁻¹) to supply plant-available P to spring wheat (TriticumaestivumL.) in either sandy loam or sandy clay loam soil. Spring wheat straw and grain P uptake were comparable across all treatments in the sandy loam, while Al/O-WTR application to the sandy clay loam reduced straw and grain P uptake. The Al/O-WTR did not affect soil organic P concentrations, but did increase phosphatase activity in both soils; this suggests that Al/O-WTR application stimulated microorganisms and enhance the extent to which microbial communities can mineralize Al/O-WTR-bound organic P. Implications: Overall, results suggest that creating a new P fertilizer from Al-WTR and agro-industrial waste sources may be a feasible alternative to mining inorganic P fertilizer sources, while protecting the environment from unnecessary waste disposal.
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Lifschitz, Eliezer, and Elliot Meyerowitz. The Relations between Cell Division and Cell Type Specification in Floral and Vegetative Meristems of Tomato and Arabidopsis. United States Department of Agriculture, February 1996. http://dx.doi.org/10.32747/1996.7613032.bard.
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Meristems were the central issue of our project. Genes that are required for cell division, cell elongation, cell proliferation and cell fate were studied in the tomato system. The analysis of the dUTPase and threonine deaminase genes, along with the dissection of their regulatory regions is completed, while that of the RNR2 and PPO genes is at an advanced stage. All these genes were isolated in our laboratory. In addition, 8 different MADS box genes were studied in transgenic plants and their genetic relevances discovered. We have also shown that a given MADS box gene can modify the polarity of cell division without affecting the fate of the organ. In vivo interaction between two MADS box genes was demonstrated and the functional dependency of the tomato agamous gene on the TM5 gene product established. We have exploited the Knotted1 meristematic gene in conjunction with tomato leaf meristematic genes to show that simple and compound leaves and, for that matter, sepals and compound leaves, are formed by two different developmental programs. In this context we have also isolated and characterized the tomato Knotted1 gene (TKnl) and studied its expression pattern. A new program in which eight different meristematic genes in tomato will be studied emerged as a result of these studies. In essence, we have shown that it is possible to study and manipulate plant developmental systems using reverse genetic techniques and have provided a wealth of new molecular tools to interested colleagues working with tomato. Similarly, genes responsible for cell division, cell proliferation and cell fate were studied in Arabidopsis floral meristems. Among these genes are the TSO1, TSO2, HANABA TARANU and UNUSUAL FLORAL ORGANS genes, each affecting in its own way the number of pattern of cell divisions, and cell fate, in developing Arabodopsis flowers. In addition, new methods have been established for the assessment of the function of regulatory gene action in the different clonal layers of developing floral meristems.
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Serkiz, S. M., and J. L. Myers. Additional Information for E-Area Vault Performance Assessment, Appendix I `Suspect Soil Performance` - Results of Modeling the Effects of Organic Matter on the Mobility of Radionuclides as it Relates to the Disposal of Wood Products in E-Area Slit Trenches. Office of Scientific and Technical Information (OSTI), April 1996. http://dx.doi.org/10.2172/626421.
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VanderGheynst, Jean, Michael Raviv, Jim Stapleton, and Dror Minz. Effect of Combined Solarization and in Solum Compost Decomposition on Soil Health. United States Department of Agriculture, October 2013. http://dx.doi.org/10.32747/2013.7594388.bard.
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In soil solarization, moist soil is covered with a transparent plastic film, resulting in passive solar heating which inactivates soil-borne pathogen/weed propagules. Although solarization is an effective alternative to soil fumigation and chemical pesticide application, it is not widely used due to its long duration, which coincides with the growing season of some crops, thereby causing a loss of income. The basis of this project was that solarization of amended soil would be utilized more widely if growers could adopt the practice without losing production. In this research we examined three factors expected to contribute to greater utilization of solarization: 1) investigation of techniques that increase soil temperature, thereby reducing the time required for solarization; 2) development and validation of predictive soil heating models to enable informed decisions regarding soil and solarization management that accommodate the crop production cycle, and 3) elucidation of the contributions of microbial activity and microbial community structure to soil heating during solarization. Laboratory studies and a field trial were performed to determine heat generation in soil amended with compost during solarization. Respiration was measured in amended soil samples prior to and following solarization as a function of soil depth. Additionally, phytotoxicity was estimated through measurement of germination and early growth of lettuce seedlings in greenhouse assays, and samples were subjected to 16S ribosomal RNA gene sequencing to characterize microbial communities. Amendment of soil with 10% (g/g) compost containing 16.9 mg CO2/g dry weight organic carbon resulted in soil temperatures that were 2oC to 4oC higher than soil alone. Approximately 85% of total organic carbon within the amended soil was exhausted during 22 days of solarization. There was no significant difference in residual respiration with soil depth down to 17.4 cm. Although freshly amended soil proved highly inhibitory to lettuce seed germination and seedling growth, phytotoxicity was not detected in solarized amended soil after 22 days of field solarization. The sequencing data obtained from field samples revealed similar microbial species richness and evenness in both solarized amended and non-amended soil. However, amendment led to enrichment of a community different from that of non-amended soil after solarization. Moreover, community structure varied by soil depth in solarized soil. Coupled with temperature data from soil during solarization, community data highlighted how thermal gradients in soil influence community structure and indicated microorganisms that may contribute to increased soil heating during solarization. Reliable predictive tools are necessary to characterize the solarization process and to minimize the opportunity cost incurred by farmers due to growing season abbreviation, however, current models do not accurately predict temperatures for soils with internal heat generation associated with the microbial breakdown of the soil amendment. To address the need for a more robust model, a first-order source term was developed to model the internal heat source during amended soil solarization. This source term was then incorporated into an existing “soil only” model and validated against data collected from amended soil field trials. The expanded model outperformed both the existing stable-soil model and a constant source term model, predicting daily peak temperatures to within 0.1°C during the critical first week of solarization. Overall the results suggest that amendment of soil with compost prior to solarization may be of value in agricultural soil disinfestations operations, however additional work is needed to determine the effects of soil type and organic matter source on efficacy. Furthermore, models can be developed to predict soil temperature during solarization, however, additional work is needed to couple heat transfer models with pathogen and weed inactivation models to better estimate solarization duration necessary for disinfestation.
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Wolf, Shmuel, and William J. Lucas. Involvement of the TMV-MP in the Control of Carbon Metabolism and Partitioning in Transgenic Plants. United States Department of Agriculture, October 1999. http://dx.doi.org/10.32747/1999.7570560.bard.
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The function of the 30-kilodalton movement protein (MP) of tobacco mosaic virus (TMV) is to facilitate cell-to-cell movement of viral progeny in infected plants. Our earlier findings have indicated that this protein has a direct effect on plasmodesmal function. In addition, these studies demonstrated that constitutive expression of the TMV MP gene (under the control of the CaMV 35S promoter) in transgenic tobacco plants significantly affects carbon metabolism in source leaves and alters the biomass distribution between the various plant organs. The long-term goal of the proposed research was to better understand the factors controlling carbon translocation in plants. The specific objectives were: A) To introduce into tobacco and potato plants a virally-encoded (TMV-MP) gene that affects plasmodesmal functioning and photosynthate partitioning under tissue-specific promoters. B) To introduce into tobacco and potato plants the TMV-MP gene under the control of promoters which are tightly repressed by the Tn10-encoded Tet repressor, to enable the expression of the protein by external application of tetracycline. C) To explore the mechanism by which the TMV-MP interacts with the endogenous control o~ carbon allocation. Data obtained in our previous project together with the results of this current study established that the TMV-MP has pleiotropic effects when expressed in transgenic tobacco plants. In addition to its ability to increase the plasmodesmal size exclusion limit, it alters carbohydrate metabolism in source leaves and dry matter partitioning between the various plant organs, Expression of the TMV-MP in various tissues of transgenic potato plants indicated that sugars and starch levels in source leaves are reduced below those of control plants when the TMV-MP is expressed in green tissue only. However, when the TMV-MP was expressed predominantly in PP and CC, sugar and starch levels were raised above those of control plants. Perhaps the most significant result obtained from experiments performed on transgenic potato plants was the discovery that the influence of the TMV-MP on carbohydrate allocation within source leaves was under developmental control and was exerted only during tuber development. The complexity of the mode by which the TMV-MP exerts its effect on the process of carbohydrate allocation was further demonstrated when transgenic tobacco plants were subjected to environmental stresses such as drought stress and nutrients deficiencies, Collectively, these studies indicated that the influence of the TMV-MP on carbon allocation L the result of protein-protein interaction within the source tissue. Based on these results, together with the findings that plasmodesmata potentiate the cell-to-cell trafficking of viral and endogenous proteins and nucleoproteins complexes, we developed the theme that at the whole plant level, the phloem serves as an information superhighway. Such a long-distance communication system may utilize a new class of signaling molecules (proteins and/or RNA) to co-ordinate photosynthesis and carbon/nitrogen metabolism in source leaves with the complex growth requirements of the plant under the prevailing environmental conditions. The discovery that expression of viral MP in plants can induce precise changes in carbon metabolism and photoassimilate allocation, now provide a conceptual foundation for future studies aimed at elucidating the communication network responsible for integrating photosynthetic productivity with resource allocation at the whole-plant level. Such information will surely provide an understanding of how plants coordinate the essential physiological functions performed by distantly-separated organs. Identification of the proteins involved in mediating and controlling cell-to-cell transport, especially at the companion cell-sieve element boundary, will provide an important first step towards achieving this goal.
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Aharoni, Asaph, Zhangjun Fei, Efraim Lewinsohn, Arthur Schaffer, and Yaakov Tadmor. System Approach to Understanding the Metabolic Diversity in Melon. United States Department of Agriculture, July 2013. http://dx.doi.org/10.32747/2013.7593400.bard.
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Fruit quality is determined by numerous genetic factors that affect taste, aroma, color, texture, nutritional value and shelf life. To unravel the genetic components involved in the metabolic pathways behind these traits, the major goal of the project was to identify novel genes that are involved in, or that regulate, these pathways using correlation analysis between genotype, metabolite and gene expression data. The original and specific research objectives were: (1) Collection of replicated fruit from a population of 96 RI lines derived from parents distinguished by great diversity in fruit development and quality phenotypes, (2) Phenotypic and metabolic profiling of mature fruit from all 96 RI lines and their parents, (3) 454 pyrosequencing of cDNA representing mRNA of mature fruit from each line to facilitate gene expression analysis based on relative EST abundance, (4) Development of a database modeled after an existing database developed for tomato introgression lines (ILs) to facilitate online data analysis by members of this project and by researchers around the world. The main functions of the database will be to store and present metabolite and gene expression data so that correlations can be drawn between variation in target traits or metabolites across the RI population members and variation in gene expression to identify candidate genes which may impact phenotypic and chemical traits of interest, (5) Selection of RI lines for segregation and/or hybridization (crosses) analysis to ascertain whether or not genes associated with traits through gene expression/metabolite correlation analysis are indeed contributors to said traits. The overall research strategy was to utilize an available recombinant inbred population of melon (Cucumis melo L.) derived from phenotypically diverse parents and for which over 800 molecular markers have been mapped for the association of metabolic trait and gene expression QTLs. Transcriptomic data were obtained by high throughput sequencing using the Illumina platform instead of the originally planned 454 platform. The change was due to the fast advancement and proven advantages of the Illumina platform, as explained in the first annual scientific report. Metabolic data were collected using both targeted (sugars, organic acids, carotenoids) and non-targeted metabolomics analysis methodologies. Genes whose expression patterns were associated with variation of particular metabolites or fruit quality traits represent candidates for the molecular mechanisms that underlie them. Candidate genes that may encode enzymes catalyzingbiosynthetic steps in the production of volatile compounds of interest, downstream catabolic processes of aromatic amino acids and regulatory genes were selected and are in the process of functional analyses. Several of these are genes represent unanticipated effectors of compound accumulation that could not be identified using traditional approaches. According to the original plan, the Cucurbit Genomics Network (http://www.icugi.org/), developed through an earlier BARD project (IS-3333-02), was expanded to serve as a public portal for the extensive metabolomics and transcriptomic data resulting from the current project. Importantly, this database was also expanded to include genomic and metabolomic resources of all the cucurbit crops, including genomes of cucumber and watermelon, EST collections, genetic maps, metabolite data and additional information. In addition, the database provides tools enabling researchers to identify genes, the expression patterns of which correlate with traits of interest. The project has significantly expanded the existing EST resource for melon and provides new molecular tools for marker-assisted selection. This information will be opened to the public by the end of 2013, upon the first publication describing the transcriptomic and metabolomics resources developed through the project. In addition, well-characterized RI lines are available to enable targeted breeding for genes of interest. Segregation of the RI lines for specific metabolites of interest has been shown, demonstrating the utility in these lines and our new molecular and metabolic data as a basis for selection targeting specific flavor, quality, nutritional and/or defensive compounds. To summarize, all the specific goals of the project have been achieved and in many cases exceeded. Large scale trascriptomic and metabolomic resources have been developed for melon and will soon become available to the community. The usefulness of these has been validated. A number of novel genes involved in fruit ripening have been selected and are currently being functionally analyzed. We thus fully addressed our obligations to the project. In our view, however, the potential value of the project outcomes as ultimately manifested may be far greater than originally anticipated. The resources developed and expanded under this project, and the tools created for using them will enable us, and others, to continue to employ resulting data and discoveries in future studies with benefits both in basic and applied agricultural - scientific research.
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Phillips, Donald A., Yitzhak Spiegel, and Howard Ferris. Optimizing nematode management by defining natural chemical bases of behavior. United States Department of Agriculture, November 2006. http://dx.doi.org/10.32747/2006.7587234.bard.
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This project was based on the hypothesis that nematodes interacting with plants as either parasites or beneficial saprophytes are attracted to their host by natural products. This concept was supported by numerous observations that parasitic nematodes are attracted to root exudates. Our overall goal was to identify nematode sensory compounds from root exudates and to use that information for reducing nematicide applications. We applied skills of the investigators to achieve three specific objectives: 1) Identify nematode behavioral cues (e.g., attractants or repellents) in root exudates; 2) Identify new natural nematicidal compounds; and 3) Combine a natural attractant and a nematicide into a nematode trap. Because saprophytic nematodes benefit plants by mineralizing organic matter, we sought compounds attractive primarily to parasitic nematodes. The project was constructed on several complementary foundations. First, data from Dr. Spiegel’s lab showed that under aseptic conditions Ditylenchus dipsaci, a parasite on onion, is attracted to certain fractions of onion root exudates. Second, PI Phillips had a sizeable collection of natural plant products he had identified from previous work on Rhizobium-legume interactions, which could be tested “off the shelf”. Third, Dr. Ferris had access to aseptic and natural populations of various saprophytic and parasitic nematodes. The project focused on five nematode species: D.dipsaci, Heterodera avenae, and Tylenchulussemipenetransat ARO, and Meloidogyne javanicand Caenorhabditis elegans at UCD. Ten pure plant compounds, mostly flavonoids, were tested on the various nematode species using six different assay systems. Results obtained with assorted test systems and by various scientists in the same test systems were essentially irreproducible. Many convincing, Many convincing, i.e. statistically significant, results in one system or with one investigator could not be repeated with other assays or different people. A recent report from others found that these compounds, plus another 30, were inactive as attractants in three additional parasitic nematode species (Wuyts et al. Nematology 8:89- 101, 2006). Assays designed to test the hypothesis that several compounds together are required to attract nematodes have thus far failed to find a reproducibly active combination. In contrast to results using pure plant compounds, complex unfractionated exudates from aseptic onion root reproducibly attracted D. dipsaci in both the ARO and UCD labs. Onion root exudate collection, separation into HPLC fractions, assays using D. dipsaci and MS-MS experiments proceeded collaboratively between ARO and UCD without any definitive identification of an active compound. The final active fraction contained two major molecules and traces of several other compounds. In the end, analytical studies were limited by the amount of onion root exudate and the complexity of the purification process. These tests showed that aseptic plant roots release attractant molecules, but whether nematodes influence that release, as insects trigger release of attractants from plants, is unknown. Related experiments showed that the saprophyte C. elegans stimulates its prey, Pseudomonas bacteria, to increase production of 2, 4-diacetylphloroglucinol (DAPG) a compound that promotes amino acid exudation by plant roots. It is thus possible that saprophytic nematodes are attracted primarily to their bacterial or fungal prey and secondarily to effects of those microorganisms on root exudation. These observations offer promising avenues for understanding root-zone interactions, but no direct routes to controlling nematodes in agriculture were evident. Extracts from two plant sources, Chrysanthemum coronarium and Sequoia sempervirens, showed nematicidal activity at ARO and UCD, respectively. Attempts to purify an active compound from S. sempervirens failed, but preliminary results from C. coronarium are judged to form a potential basis for further work at ARO. These results highlight the problems of studying complex movement patterns in sentient organisms like nematodes and the issues associated with natural product isolation from complex mixtures. Those two difficulties combined with complications now associated with obtaining US visas, slowed and ultimately limited progress on this project. As a result, US investigators expended only 65% of the $207,400 originally planned for this project. The Israeli side of the project advanced more directly toward its scientific goals and lists its expenditures in the customary financial report.
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Ostersetzer-Biran, Oren, and Alice Barkan. Nuclear Encoded RNA Splicing Factors in Plant Mitochondria. United States Department of Agriculture, February 2009. http://dx.doi.org/10.32747/2009.7592111.bard.
Full textAbstract:
Mitochondria are the site of respiration and numerous other metabolic processes required for plant growth and development. Increased demands for metabolic energy are observed during different stages in the plants life cycle, but are particularly ample during germination and reproductive organ development. These activities are dependent upon the tight regulation of the expression and accumulation of various organellar proteins. Plant mitochondria contain their own genomes (mtDNA), which encode for a small number of genes required in organellar genome expression and respiration. Yet, the vast majority of the organellar proteins are encoded by nuclear genes, thus necessitating complex mechanisms to coordinate the expression and accumulation of proteins encoded by the two remote genomes. Many organellar genes are interrupted by intervening sequences (introns), which are removed from the primary presequences via splicing. According to conserved features of their sequences these introns are all classified as “group-II”. Their splicing is necessary for organellar activity and is dependent upon nuclear-encoded RNA-binding cofactors. However, to-date, only a tiny fraction of the proteins expected to be involved in these activities have been identified. Accordingly, this project aimed to identify nuclear-encoded proteins required for mitochondrial RNA splicing in plants, and to analyze their specific roles in the splicing of group-II intron RNAs. In non-plant systems, group-II intron splicing is mediated by proteins encoded within the introns themselves, known as maturases, which act specifically in the splicing of the introns in which they are encoded. Only one mitochondrial intron in plants has retained its maturaseORF (matR), but its roles in organellar intron splicing are unknown. Clues to other proteins required for organellar intron splicing are scarce, but these are likely encoded in the nucleus as there are no other obvious candidates among the remaining ORFs within the mtDNA. Through genetic screens in maize, the Barkan lab identified numerous nuclear genes that are required for the splicing of many of the introns within the plastid genome. Several of these genes are related to one another (i.e. crs1, caf1, caf2, and cfm2) in that they share a previously uncharacterized domain of archaeal origin, the CRM domain. The Arabidopsis genome contains 16 CRM-related genes, which contain between one and four repeats of the domain. Several of these are predicted to the mitochondria and are thus postulated to act in the splicing of group-II introns in the organelle(s) to which they are localized. In addition, plant genomes also harbor several genes that are closely related to group-II intron-encoded maturases (nMats), which exist in the nucleus as 'self-standing' ORFs, out of the context of their cognate "host" group-II introns and are predicted to reside within the mitochondria. The similarity with known group-II intron splicing factors identified in other systems and their predicted localization to mitochondria in plants suggest that nuclear-encoded CRM and nMat related proteins may function in the splicing of mitochondrial-encoded introns. In this proposal we proposed to (i) establish the intracellular locations of several CRM and nMat proteins; (ii) to test whether mutations in their genes impairs the splicing of mitochondrial introns; and to (iii) determine whether these proteins are bound to the mitochondrial introns in vivo.