Dissertations / Theses: 'Plant nutrients'

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Muskolus, Andreas. "Anthropogenic plant nutrients as fertiliser." Doctoral thesis, Humboldt-Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 2008. http://dx.doi.org/10.18452/15774.

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Nachhaltige Landbewirtschaftung impliziert ausgeglichene Pflanzennährstoffflüsse ohne die Abhängigkeit von Düngern aus nicht erneuerbaren Quellen. Stickstoff, Phosphor und Kalium aus der menschlichen Nahrung werden in Mitteleuropa im Allgemeinen in Schwemmkanalisationen gesammelt und dabei mit Schadstoffen vermengt. Neuartige stoffstromtrennende Sanitärsysteme ermöglichen die Bereitstellung von Humanurin und Fäkalien zur Verwendung als Düngemittel. In der vorliegenden Arbeit wurden praxisrelevante Aspekte der Verwendung von Düngemitteln anthropogener Herkunft untersucht. Die in Gefäß- und Feldversuchen in Berlin Dahlem ermittelte Ertragswirkung zeigte, dass Urin in dieser Hinsicht äquivalenten Mineraldüngern grundsätzlich gleichwertig ist. Bei sehr hohen Konzentrationen kam es abhängig von der Pflanzenart zu Depressionseffekten, welche vermutlich auf den Salz- und Ammoniumgehalt von Urin zurückzuführen sind. Unter Freilandbedingungen traten diese Effekte nicht auf. Bodenbiologische Auswirkungen von Düngerapplikationen sind entscheidend für die Abschätzung ihrer langfristigen Bodenfruchtbarkeitserhaltung. Sowohl in Labor-versuchen als auch im Freiland zeigten sich Regenwürmer durch menschlichen Urin aus Trenntoiletten deutlich beeinträchtigt. Die Ursache der Schädigung konnte nicht geklärt werden. Von einer langfristigen bodenfruchtbarkeitsreduzierenden Beein-trächtigung wird jedoch nicht ausgegangen. Mikrobielle Enzymaktivitäten im Boden wurden im Freiland durch Urinapplikation nicht beeinflusst. Für die Praxis wird empfohlen Urin während der Ausbringung einzuarbeiten, da die Tiere dann weniger mit der Flüssigkeit in Kontakt kommen. Da es ein umweltpolitisches Ziel ist, die Ammoniakemissionen der Landwirtschaft zu minimieren, wurden diese nach der Urinausbringung im Freiland gemessen. Auf Grund der sehr geringen Trockensubstanzgehalte von Humanurin emittierte deutlich weniger NH3 als üblicherweise nach Ausbringung von Schweine- oder Rindergülle. Verbraucherumfragen bestätigten eine hohe Bereitschaft pflanzliche Nahrung, welche mit Urin als Dünger erzeugt wurde, zu kaufen und zu verzehren. Praktizierende Landwirte reagierten dagegen deutlich reservierter. Die Ausbringung von Urin aus Trenntoiletten kann im Sinne einer nachhaltigen Landwirtschaft grundsätzlich empfohlen werden. Es besteht aber weiterer Forschungsbedarf.
Sustainable agriculture implies balanced nutrient flows and independence from fertiliser made from non renewable resources. In Europe, plant nutrients excreted by humans are commonly collected in water borne sewage systems and thus mixed with potentially harmful substances. Novel segregating sanitation techniques can collect separated urine and faeces in a form which enables their use as fertiliser. In the presented thesis selected aspects concerning the use of anthropogenic plant nutrients relevant to farming were investigated. Pot and field experiments indicated that equal yields can be gained if urine instead of mineral fertiliser is applied. Very high concentrations of urine led to reduced growth, presumably caused by the presence of ammonium or salt. However, this was not found under field conditions. Soil biological effects caused by the application of a fertiliser must be considered when assessing its long term contribution to soil fertility. Laboratory experiments as well as field investigations showed that human urine application severely affects earthworms, however, the harmful components were not identified. The results suggest that the effect is of short term only. Soil microbial enzyme activities were not influenced by urine fertiliser. For farming practice it is recommended to inject or incorporate urine to prevent earthworms from coming into direct contact with the infiltrating fertiliser. Gaseous ammonia loss was measured after urine application on fields as reducing harmful emissions from agriculture is a goal of European environmental policy. Because of the very low Dry Matter contents of urine, far less ammonia was emitted to the atmosphere than usually occurs after application of cattle or pig slurry. A consumer acceptance study showed a general high public willingness to accept urine as fertiliser even if used on crops for food production. The reaction of farmers was mainly reserved as a result of the present legal regulations in Germany. Within the context of sustainable agriculture the use of human urine as fertiliser can be recommended. Further research is necessary, especially concerning any effects resulting from residues of pharmaceutical substances contained in human excreta.

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Tancock, Nigel Philip. "The influence of complexation on micronutrient uptake by plants and on plant growth." Thesis, University of Leicester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341363.

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Ferreira, Francisco Jardelson. "Fertilization rose bushes based on nutrient balance in the soil - plant system." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17134.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
Rose is an economically important crop for the national and the international market and due to this fact generates income to the Ceara State. Rose is a demanding crop in relation to fertilizers, requiring knowledge of soil fertility, nutritional plant requirements and nutrients use efficiency to obtain adequate fertilization. Based on the nutritional balance through the use of mechanistic and empirical models, it is possible to develop a system to quantify the plant nutrients demands to achieve a given productivity. This paper aims to establish parameters of a fertilizer and lime recommendation system to rose crop, based on the plant nutritional balance. The experiment was conducted at the company Cearosa in SÃo Benedito - CE. Plants will be collected during five months and once a month, five rose plants from four varieties (Top Secret, Avalanche, Attache and Ambience) As contradictory Airlines plants Were grinded. Samples will be ground and nutrients content will be determined: N, P, K, Ca, Mg, S, B, Fe, Mn, e Zn. Every sampling plant time, were also soil samples collected at two depths (0-20 and 20-40 cm) In which they underwent fertility analysis. To estimate the fertilizer recommendation, the system was be subdivided into requirement subsystem (REQ), which includes the plant nutrients demands, considering the recovery efficiency of the nutrients to be applied and a rate to achieve the "sustainability" criteria and the supply subsystem (SUP) that comprises the soil nutrient supply. After determining the total REQ and SUP, held -if the nutritional balance, and if the result is positive (REQ> SUP), fertilizers application is recommended and if the result negative or zero (REQ ≤ SUP), fertilizers application is not recommended. The system estimated that there is excess nitrogen and phosphorus fertilization for all cultivars , however , there needs to be supplemental potassium fertilizer . The system estimated that the soil is able to meet the demand of plants for P and Fe for all cultivars , however , there must be supplementary nitrogen fertilizer , potassium . As for micronutrients , the system estimated that there is need for additional fertilizer for Zn in all rosebushes and Mn for the rosebushes "Top Secret " and " Avalnche " , however with very close recommendation the optimal dose , ie equal to zero
A roseira Ã uma cultura de grande valor no mercado interno e externo, devido a esse fato, as rosas geram benefÃcios para o estado do CearÃ. Ã uma cultura muito exigente em relaÃÃo Ã adubaÃÃo, sendo necessÃrios conhecimentos da fertilidade do solo, exigÃncias nutricionais da planta e eficiÃncia na utilizaÃÃo de nutrientes, para obtenÃÃo de uma adubaÃÃo adequada. Partindo a hipÃtese de que conhecendo-se o balanÃo nutricional da cultura, levando-se em consideraÃÃo a demanda de nutrientes pela cultura para alcanÃar uma dada produtividade e o suprimento de nutrientes pelo solo, Ã possÃvel determinar a quantidade de nutrientes a ser adicionada na fertilizaÃÃo do solo. O presente trabalho tem como objetivo determinar com base no balanÃo de nutrientes solo-planta a quantidade de nutrientes a ser adicionada no solo para cultura da roseira. O experimento foi conduzido na empresa Cearosa, em SÃo Benedito - CE, as plantas foram coletadas durante cinco meses, sendo uma vez por mÃs, amostrando cinco plantas aleatÃrias, de quatro cultivares de rosas: (Top Secret, Avalanche, Attache e Ambience). As partes aÃreas das plantas foram moÃdas e mineralizadas para determinaÃÃo dos teores dos nutrientes: N, P, K, Ca, Mg, S, B, Fe, Mn e Zn. Simultaneamente a coleta de plantas, tambÃm foram coletadas amostras de solo em duas profundidades, camada de 0 a 20 e de 20 a 40cm. Na qual foram submetidas Ã anÃlise de fertilidade. Para estimar a recomendaÃÃo de adubaÃÃo o sistema foi subdividido em: subsistema requerimento (REQ), que contempla a demanda de nutrientes pela planta, considerando a eficiÃncia de recuperaÃÃo dos nutrientes a serem aplicados, alÃm de uma dose que atende ao critÃrio de âsustentabilidadeâ e o subsistema suprimento (SUP), que corresponde Ã oferta de nutrientes pelo solo. ApÃs a determinaÃÃo do REQ total e SUP total, realizou -se o balanÃo nutricional, no qual se apresentar resultado positivo (REQ > SUP), recomenda-se a aplicaÃÃo de fertilizantes, e negativo ou nulo (REQ ≤ SUP), nÃo serÃ recomendado aplicar fertilizantes. O sistema estimou que o solo Ã capaz de suprir a demanda das plantas para P e Fe para todas as cultivares, no entanto, Ã necessÃrio que haja complementaÃÃo de adubaÃÃo nitrogenada, potÃssica. Assim como para os micronutrientes, o sistema estimou que hÃ necessidade de complementaÃÃo de adubaÃÃo, para Zn em todas as roseiras e Mn para as roseiras âTop secretâ e âAvalncheâ, no entanto com a recomendaÃÃo bem prÃximos a dose ideal, ou seja, igual a zero

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Elsey-Quirk, Tracy. "Inter- and intraspecific variation in carbon and nutrient pools of salt marsh plants." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 236 p, 2010. http://proquest.umi.com/pqdweb?did=1993336371&sid=9&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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POLZELLA, Antonella. "Plant response to modified conditions of light and nutrients." Doctoral thesis, Università degli studi del Molise, 2019. http://hdl.handle.net/11695/90862.

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In natura la crescita, lo sviluppo, la produttività e la distribuzione delle piante sono altamente influenzati da un ampio numero di diversi fattori biotici e abiotici. Tra tutti i fattori biotici, l’acqua, la temperatura, la luce e i nutrienti restano quelli di maggiore rilevanza. Così come resta di fondamentale importanza lo studio dei meccanismi della crescita e delle risposte di adattamento delle piante ai cambiamenti della disponibilità di queste stesse componenti ambientali. In tale contesto, il presente lavoro di tesi mira ad ampliare la conoscenza sulla risposta delle piante alla disponibilità modificata di nutrienti nel suolo e alla manipolazione qualitativa e quantitativa dello spettro di luce. Per conseguire questo obiettivo sono stati studiati gli effetti dei cambiamenti nella disponibilità di nutrienti nel terreno attraverso l’aggiunta di un ammendante organico quale il biochar, invece le alterazioni sia qualitative che quantitative dello spettro di luce sono state ottenute usando diversi sistemi di illuminazione artificiale. Il biochar è stato utilizzato solo ed in combinazione con diversi spettri di luce, di cui gli effetti sono stati analizzati sia al livello morfo-fisiologico che molecolare in diverse piante (ad es. pomodoro, pisello e Arabidopsis). I risultati ottenuti in questa tesi dimostrano che sebbene il biochar aggiunto nel terreno porta ad uno squilibrio dell’apparato fotosintetico nelle piante di pomodoro, esso potrebbe migliorare la crescita delle piante di Pisum e Arabidopsis, in maggior misura se si utilizza in combinazione con una luce caratterizzata da una specifica composizione spettrale. Inoltre, la risposta morfo-fisiologica delle piante porta ad ipotizzare che i fotorecettori, come phyA, phyB e fattori coinvolti nella segnalazione luminosa come pifs potrebbero essere convolti in processi di stimolazione della crescita in condizioni di stress di luce e di azoto. Come parte del progetto di dottorato, sono stati studiati gli effetti di un nuovo sistema di illuminazione artificiale chiamato CoeLux® sulla morfo-fisiologia di diverse specie di piante (ad es. Anthurium, Basilicum, Q. ilex). Gli esperimenti con il sistema di illuminazione CoeLux® hanno dimostrato un meccanismo di risposta specie-specifico ed un’alta efficienza della pianta nel ricevere ed usare la luce CoeLux® attraverso lo svolgimento di una buona attività sia fotosintetica che stomatica.
In natural environments plant growth, development, productivity, and distribution are highly dependent on a wide number of different biotic and abiotic factors. Among all water, temperature, light, and nutrients are the most important ones. Understanding mechanisms and adaptive responses of plant growth to changes in the availability of these environmental components is of the fundamental importance. In this framework, the present thesis aimed at widen the knowledge on plant response to modifications of soil nutrient availability and to the alteration in quality and quantity of light spectrum. To accomplish this aim, the effects of changes in nutrient composition have been investigated by adding biochar amendment to the soil, whereas alterations in quality and quantity of light spectrum have been obtained by using different artificial lighting systems. The response to biochar soil amendment has been analyzed at morpho-physiological and molecular levels in different plant species (i.e. tomato, pea and Arabidopsis), alone and in combination with light spectra alterations. Results obtained in this thesis show that although biochar addition misbalances the photosynthetic machinery in tomato plants, it might improve Pisum and Arabidopsis growth, even at higher magnitude when the light spectrum is characterized by a specific composition. In addition, morpho-physiological plant response leads to hypothesize that photoreceptors such as phyA, phyB, and light signaling components such as pifs, could be involved in processes of growth stimulation in nitrogen and light stress conditions. As part of the Ph.D project, the effects of a new artificial lighting system named CoeLux®, on morpho-physiology of several different plant species (i.e. Anthurium, Basilicum, Q. ilex) have been investigated. Experiments with CoeLux® lighting system showed a species-specific plant response mechanism and a high plant efficiency to receive and use CoeLux® lighting system by performing good photosynthetic and stomatal activities.

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Schweizer, Amelia Lee. "Determination and assessment of procedures of the pour-through nutrient extraction procedure for bedding flats and plug trays." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-10312009-020402/.

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Kapira, Elvanus. "EFFECTS OF PLANT HARVESTING ON NUTRIENTS REMOVAL IN CONSTRUCTED WETLANDS." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-35170.

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Insufficient access to clean water and sanitation has become one of the most universal problems affecting human health in developing countries, water resources are facing high pollution rate due to improper management of wastewater. Ecological technologies such as constructed wetlands are promising innovative solutions for this universal problem. Constructed wetlands are engineered wastewater treatment systems that include treatment segments such as physical, chemical, and biological processes like in natural wetlands. Plant harvesting practice is one management strategy that can prevent these systems from clogging and loss of surface area, the effects of this management strategy need to be assessed related to the performance of wetlands. The aim of this thesis was to investigate the effects of plants harvesting on nutrients removal (N, P, and COD) in constructed wetlands. This is a literature review and experimental based thesis. The literature review involved reviewing 5 studies about effect of harvesting plants in constructed wetlands. The experiment part involved data analysis from 6 experimental wetlands, with 3 wetlands that have been harvested in 2015 and 2016, another 3 wetlands that have never been harvested. Results from literature review indicated that plant harvesting in wetland has a significant effect in nutrients removal. Experiment results indicated that there was significant difference between these wetlands in TN and NO3-N removed when the entire operation period was considered (P=0.005). But when each season was considered separately statistical differences were only observed during first summer after harvesting for TN removal. For NO3-N, differences between wetlands were observed in first summer and winter only. For summer, harvested wetland performed better than non-harvested wetland, but in winter non-harvested wetland performed better than harvested in terms of NO3-N removal. For winter, the reason to this could be that, some of plants parts decay and provided denitriﬁcation bacteria with a carbon source which accelerates denitrification process. According to this study, plants harvesting in wetland generally has a positive effect on nutrient removal such as TN, TP, COD, and BOD. Therefore, this practice could be recommended as the best wetland plants management to improve and maintain nutrient removal in constructed wetlands.

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Naku, Mandilakhe. "Functional role of ammonium and nitrate in regulating transpiration for mass-flow acquisition of nutrients in Phaseolus vulgaris L." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2679.

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Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2017
Transpiration serves in leaf cooling, maintaining turgor pressure, promoting xylem transport of nutrient solutes from roots to shoots and delivering mobile soil nutrients to root surfaces. Soil availability of nitrogen can modulate transpiration rates, consequently powering nutrient delivery to the root surfaces (‗mass-flow'). Although such knowledge on N-regulation of transpiration is available, it remains unknown, however, whether it is NO3- or NH4+ that regulates transpiration. Given that both nitrogen forms co-occur in soils, it is not known how they interact at varying ratios in modulating stomatal behaviour. To test the functional role of NO3- and NH4+ in regulating water fluxes for mass-flow nutrient acquisition, P. vulgaris L. plants were grown with NO3- or NH4+ placed at one of four distances behind a nylon mesh, which prevented direct root access to nitrogen, whilst control plants intercepted the nitrogen source (Chapter 3). Day- and night-time stomatal conductance and transpiration, measured using Infra-Red Gas Analyser (IRGA) declined in NO3- fed plants with the increased distance behind a nylon mesh, with maximum water fluxes at the closest distance (ca. 0 mm), demonstrating a regulatory role of NO3- on stomata closure. An opposite trend was displayed by NH4+ -fed plants, which indicated the incapacity of NH4+ to down-regulate water fluxes and ammoniacal syndrome at high concentrations. To test how different [NO3-] and [NH4+] regulate day- and night-time stomatal conductance and transpiration (Chapter 4), P. vulgaris was fed with six concentrations (0, 0.25, 0.5, 1, 2, 4 and 8 mM) of each nitrogen form. A biphasic trend emerged, as postulated in previous studies (Wilkinson et al., 2007; Matimati et al., 2013), characterized by an increase in stomatal conductance and transpiration as [NO3-] increased, attaining a maximum before declining with higher [NO3-]. Plants displayed 2-fold higher photosynthetic rates, 2.2-fold higher stomatal conductance and 2.3-fold higher transpiration rates at 4 mM than at 0.25 mM of [NO3-]. The lowest [NO3-] up-regulated night-time stomatal conductance and transpiration, indicating that NO3- -fed plants opened their stomata at night-time, but reduced night-time water loss at higher [NO3-]. NH4+-fed plants had the incapacity to regulate day- and night-time water fluxes, but rather displayed wilting and stress known as ‗ammoniacal syndrome'. Thus, under NO3- deprived soil conditions P. vulgaris may be opportunistic in their water uptake, transpiring more when water is available in order to draw nutrients through ‗mass-flow'. This thesis explored and confirmed the functional role of NO3- in regulating day- and night-time water fluxes as a mechanism for increasing ‗mass-flow' acquisition of N and possibly other nutrients, signalling a down-regulation of day-time and night-time water fluxes when [NO3-] is replete (Chapter 3 & 4). Where both NO3- and NH4+ are present in soils, it is the [NO3-] and not [NH4+] that regulated stomatal conductance and transpiration. Since organic nitrogen forms such as amino acids also occur in soils, there is a need for further work on their role in stomatal behaviour. Using amino acids laced with 15N isotopes as a nitrogen source can allow their acquisition and role on stomatal behaviour to be discovered. Current trends in research are focussed around developing real-time in-situ sensing of soil nitrogen status to promote enhanced nitrogen and water use efficiency in agricultural systems. This thesis provides the vital literature on stomatal regulation by [NO3-].

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Stone, Bethany. "The effects of boron deficiency and aluminum toxicity on plant magnesium /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3036861.

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Flores-Meza, Diego M. "Modeling metal uptake by barley plants (Hordeum vulgare) in nutrient solution." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 159 p, 2008. http://proquest.umi.com/pqdweb?did=1597632531&sid=49&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Lister, James Edward. "The behaviour of plant nutrients in colliery spoil of Central Scotland." Thesis, University of Glasgow, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335480.

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Chege, Ayub Getheyo. "Management of plant nutrients in smallholder farming systems of Western Kenya." Thesis, University of Exeter, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341197.

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Matlhoahela, Patience Tshegohatso. "Mineral nutrition of cultivated South African proteaceace." Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1106.

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Pritchard, Deborah Leeanne. "Phosphorus bioavailability from land-applied biosolids in south-western Australia." Thesis, Curtin University, 2005. http://hdl.handle.net/20.500.11937/2380.

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The annual production of biosolids in the Perth region during the period of this study was approximately 13,800 t dry solids (DS), being supplied by three major wastewater treatment plants. Of this, 70% was typically used as a low-grade fertiliser in agriculture, representing an annual land use area of around 1,600 ha when spread between 5 and 7 t DS/ha. Loading rates of biosolids are typically based on the nitrogen (N) requirements of the crop to be grown, referred to as the N Limiting Biosolids Application Rate (NLBAR). A consequence of using the NLBAR to calculate loading rates is that phosphorus (P) is typically in excess of plant requirement. The resultant high loading rates of P are considered in the guidelines developed for the agricultural use of biosolids in Western Australia, but lack research data specific to local conditions and soil types. Regulatory changes throughout Australia and globally to protect the environment from wastewater pollution have created a need for more accountable and balanced nutrient data. Experiments presented in this thesis were undertaken to ascertain: the percentage relative effectiveness (RE) of biosolids as a source of plant available P compared with inorganic P fertiliser; loading rates to best supply P for optimum crop growth; P loading rates of risk to the environment; and the forms of P in local biosolids. Therefore, both the agronomic and environmental viewpoints were considered. Anaerobically digested and dewatered biosolids produced from Beenyup Wastewater Treatment Plant, Perth with a mean total P content of 2.97% dry weight basis (db) were used in a series of glasshouse, field and laboratory experiments. The biosolids were sequentially fractionated to identify the forms of P present and likewise in soil samples after applying biosolids or monocalcium phosphate (MCP).The biosolid P was predominantly inorganic (92%), and hence the organic fraction (8%) available for mineralisation at all times would be extremely low. The most common forms of biosolid P were water-soluble P and exchangeable inorganic P (66%), followed by bicarbonate extractable P (19%) and the remaining P as inorganic forms associated with Fe, Al and Ca (14%). Following the application of biosolids to a lateritic soil, the Fe and Al soil fractions sorbed large amounts of P, not unlike the distribution of P following the addition of MCP. Further investigation would be required to trace the cycling of biosolid P in the various soil pools. The growth response of wheat (Triticum aestivum L.) to increasing rates of biosolids and comparable rates of inorganic P as MCP, to a maximum of 150 mg P/kg soil was examined in the glasshouse. The percentage relative effectiveness (RE) of biosolids was calculated using fitted curve coefficients from the Mitscherlich equation: y = a (1-b exp–cx) for dry matter (DM) production and P uptake. The initial effectiveness of biosolid P was comparable to that of MCP with the percentage RE of biosolids averaging 106% for DM production of wheat shoots and 118% for shoot P uptake at 33 days after sowing (DAS) over three consecutive crops. The percentage residual value (RV) declined at similar rates for DM production in MCP and biosolids, decreasing to about 33% relative to freshly applied MCP in the second crop and to approximately 16% in the third crop. The effectiveness of biosolid P was reduced significantly compared with inorganic P when applied to a field site 80 km east of Perth (520 mm annual rainfall). An infertile lateritic podsolic soil, consistent with the glasshouse experiment and representative of a soil type typically used for the agricultural application of biosolids in Western Australia was used.Increasing rates of biosolids and comparable rates of triple superphosphate (TSP), to a maximum of 145 kg P/ha were applied to determine a P response curve. The percentage RE was calculated for seasonal DM production, final grain yield and P uptake in wheat followed by lupin (Lupinus angustifolius L.) rotation for the 2001 and 2002 growing seasons, respectively. In the first year of wheat, the RE for P uptake in biosolids compared with top-dressed TSP ranged from 33% to 55% over the season and by grain harvest was 67%. In the second year, and following incorporation with the disc plough at seeding, the RE for P uptake by lupins in biosolids averaged 79% over the growing season compared with top-dressed TSP, and by grain harvest the RE was 60%. The residual value (RV) of lupins at harvest in biosolids compared with freshly applied TSP was 47%. The non-uniform placement of biosolids (i.e. spatial heterogeneity) was primarily responsible for the decreased ability of plant roots to absorb P. The P was more effective where biosolids were finely dispersed throughout the soil, less so when roughly cultivated and least effective when placed on the soil surface without incorporation. The RE for grain harvest of wheat in the field decreased from 67% to 39% where biosolids were not incorporated (i.e. surface-applied). The RE could also be modified by factors such as soil moisture and N availability in the field, although it was possible to keep these variables constant in the glasshouse. Consequently, absolute values determined for the RE need to be treated judiciously. Calculations showed that typical loading rates of biosolids required to satisfy agronomic P requirements of wheat in Western Australia in the first season could vary from 0 to 8.1 t DS/ha, depending on soil factors such as the P Retention Index (PRI) and bicarbonate available P value.Loading rates of biosolids were inadequate for optimum P uptake by wheat at 5 t DS/ha (i.e. 145 kg P/ha) based on the NLBAR on high P sorbing soils with a low fertiliser history (i.e. PRI >15, Colwell bicarbonate extractable P <15 mg P/kg). On soils of PRI <2 mL/g however, biosolids applied at identical loading rates would result in high concentrations of available P. Further work on sites not P deficient would be necessary to validate these findings on farmed soils with a regular history of P fertiliser. The sieving of soil samples used in the field experiment to remove stones and coarse organic matter prior to chemical analysis inadvertently discarded biosolids particles >2 mm, and thus their was little relationship between soil bicarbonate extractable P and P uptake by plants in the field. The risk of P leaching in biosolids-amended soil was examined over a number of different soil types at comparable rates of P at 140 mg P/kg (as either biosolids or MCP) in a laboratory experiment. Given that biosolids are restricted on sites prone to water erosion, the study focussed on the movement of water-soluble P by leaching rather than by runoff of water-soluble P and particulate P. In general the percentage soluble reactive P recovered was lower in soils treated with biosolids than with MCP, as measured in leachate collected using a reverse soil leachate unit. This was particularly evident in acid washed sand with SRP measuring 14% for biosolids and 71% for MCP, respectively, although the differences were not as large in typical agricultural soils. Specific soil properties, such as the PRI, pH, organic carbon and reactive Fe content were negatively correlated to soluble reactive P in leachate and thus reduced the risk of P leaching in biosolids-amended soil.Conversely, the total P and bicarbonate extractable P status of the soils investigated were unreliable indicators as to the amount of P leached. On the basis of the experiments conducted, soils in Western Australia were categorised according to their ability to minimise P enrichment and provide P necessary for crop growth at loading rates determined by the NLBAR. Biosolids applied at the NLBAR to soils of PRI >2mL/g with reactive Fe >200 mg/kg were unlikely to necessitate P loading restrictions. Although specific to anaerobically digested biosolids cake applied to Western Australian soils, the results will be of relevance to any industry involved in the land application of biosolids, to prevent P contamination in water bodies and to make better use of P in crop production.

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Flower, Charlotte Amanda. "Atmospheric inputs of nutrients and pollutants to uplands in north-east Scotland." Thesis, University of Aberdeen, 1987. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU010068.

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The effects of vegetation size and architecture, in combination with elevation effects, on the amounts of atmospheric inputs of both nutrient and pollutant substances were studied by means of collecting precipitation both above and below tree and heather canopies. Use was made of 'filter' type gauges, designed to enhance interception deposition, in order to identify the main ionic substances associated with this deposition type. Results illustrate how effects of tree size and shape, as well as elevation, are tempered by local topographic and climatic factors. The total leaf area of the canopy is not necessarily an over-riding factor in determining amounts of atmospheric deposits caught by the canopy; canopy structure is seen to be equally as important. As well as a main two year field study, secondary experiments were carried out to test filter gauge design (both in the field and the laboratory). These included looking at elevation effects on interception deposition, and dry deposition estimates were made through washing of gauges and also by collection of precipitation on an event basis. Filter gauge design studies illustrated that gauge design has little effect on amounts of interception deposition collected; over the range of particle sizes and micrometeorological conditions encountered in the field, the differences in relative efficiencies of the different gauge types are of little consequence. At a site with a relatively unhindered fetch, interception deposition was seen to increase with elevation. Dry deposition was not considered to be a significant input at this site. Pb was studied as an exemplary heavy metal; it seems that Pb input is predominantly through rain (rather than being associated more with the 'filter' component of precipitation) suggesting long-range transport. Pb was found to accumulate within the organic horizons of the soil---the pathway through the ecosystem being predominantly adsorption onto plant surfaces from the rain, and then falling to the ground as litter.

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16

Rutten, Karin. "Studies on the biomass, diversity and nutrient relationships of macroalgae and seagrasses in Lake Illawarra, New South Wales, Australia." School of Earth and Environmental Sciences - Faculty of Science, 2007. http://ro.uow.edu.au/theses/22.

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Lake Illawarra is a shallow barrier lagoon, located on the south-eastern coast of Australia. Eutrophication, referring to the enrichment of water by inorganic plant nutrients (primarily nitrogen and phosphorus), is one of the key environmental problems in Lake Illawarra. Management of macroalgae in Lake Illawarra is a major issue; excessive blooms of macroalgae, resulting in odours, access problems and community concern over Lake health, have led to many management strategies, including direct harvesting of algal biomass. Little information is available on the factors responsible for excessive growth of macroalgae in Lake Illawarra, although over supply of nutrients has often been cited as the primary cause. The aim of this study was to investigate the distribution, diversity, biomass and nutrient relationships of seagrasses and macroalgae in Lake Illawarra, and to determine what contribution, if any, macrophytes make to the Lake’s nutrient budget. Firstly, detailed species lists and taxonomic descriptions were prepared for macrophytes occurring in Lake Illawarra, between June 2000 and July 2003. This study focused primarily on shallow (< 1 m depth), inshore areas of Lake Illawarra, where problematic macroalgal blooms frequently occur. Seagrasses found in Lake Illawarra are Zostera capricorni, Ruppia megacarpa, Halophila ovalis and Halophila decipiens. In addition, 35 species of macroalgae were recorded and described; these included: 14 species from 7 genera of green macroalgae; 9 species from 9 different genera of brown macroalgae; and, 8 species from 8 genera of red macroalgae. The biomass of seagrasses and macroalgae in Lake Illawarra were documented seasonally (winter and summer) at four key Lake Illawarra sites; these included two R. megacarpa sites and two Z. capricorni sites. Average R. megacarpa and Z. capricorni dry weight (DW) biomasses (above and below-ground material) ranged from 54.8 - 440 g DW m 2 and 58.1 - 230 g DW m 2, respectively. Significant die-back, particularly of Z. capricorni, occurred in winter; summer biomasses were up to 1.5 - 3.9 times higher than winter biomasses. Below-ground material (roots and rhizomes) comprised 20 - 45 % and 40 - 67 % of total plant biomass for R. megacarpa and Z. capricorni, respectively. Macroalgal biomass in 2000-03 was notably lower than in previous decades; this may be due to drought, as well as improvements in water quality. Maximum biomasses of macroalgae recorded in the present study were 150 - 370 g DW m 2. Algal blooms were composed primarily of the filamentous chlorophytes, Chaetomorpha linum and Chaetomorpha billardierii. The highest seagrass (R. megacarpa) and macroalgal biomasses usually occurred at the Oasis Caravan Park site, located along the eastern Lake Illawarra peninsula. Tissue nutrient analyses were conducted on the most abundant seagrasses (Z. capricorni and R. megacarpa) and macroalgae occurring at four sites in Lake Illawarra, between spring 2000 and winter 2002. Total C contents of macrophytes varied from 23.3 - 42.0 % C for seagrasses, and 28.0 - 39.7 % C for macroalgae. The δ13C and δ15N contents of seagrasses ranged from -7.7 to 15.9 ‰ and 0.7 - 9.0 ‰, respectively. The most significant seasonal variations in seagrass δ13C contents and, to a lesser extentδ15N contents, occurred in Z. capricorni located at the source of fresh water input, Mullet Creek. Macroalgae showed a greater variation in isotopic signatures than the seagrasses, ranging from 4.9 to 19.8 ‰ (δ13C) and 1.8 - 14.6 ‰ (δ15N). Differences between species at the same site were often more significant than differences between the same species at different sites. Seagrass leaf N and P contents ranged from 1.74 - 4.13 % (mean ± s.e.: 2.62 ± 0.05 % N) and 0.12 - 0.59 % P (mean ± s.e.: 0.31 ± 0.01 % P); leaf N and P contents were typically double those of roots/rhizomes. N contents varied between species and sites, but P contents of Z. capricorni were usually significantly higher than R. megacarpa. Z. capricorni C and N contents increased in winter, corresponding to lower winter biomasses. Seagrass leaf biomass and tissue P contents peaked in summer 2002, which may be related to higher water column P concentrations in summer. Tissue N and P contents of macroalgae were more variable than those of the seagrasses, and ranged from 0.85 - 3.95 % N and 0.03 - 0.58 % P. The average C/P (808 ± 65) and N/P (47.9 ± 3.47) molar ratios of macroalgae were typically double those of the seagrasses. Low concentrations of tissue P, with respect to N, in R. megacarpa and macroalgae implied P limitation on several occasions, particularly when macrophyte biomasses were low. High tissue N contents in Lake Illawarra macrophytes suggested N limitation of biomass formation rarely occurred. Evidence of P, rather than N, limitation in macrophytes is surprising considering most data suggests N limitation of phytoplankton production in Lake Illawarra. The estimated pools of N and P contained in Lake Illawarra macrophyte biomass were similar to those present in the water column, but appeared minute when compared to the N and P stored within Lake Illawarra sediment. Laboratory culture experiments were conducted to evaluate the response of the most problematic alga, Chaetomorpha linum, to nutrient enrichment. Water temperatures of 20 - 25°C were found to promote the highest growth rates (up to 27 % WW d 1) of C. linum, but high growth rates (13 % WW d 1) were also recorded at 10°C, the lowest winter water temperature recorded in Lake Illawarra. Enrichment with N, rather than P, had the greatest effect on C. linum; growth rates were significantly reduced in treatments without added N, but treatments with N-alone were statistically similar to N+P treatments. It was concluded that in Lake Illawarra, C. linum was strongly nitrogen limited. The ability of C. linum to grow successfully in culture, under a range of nutrient treatments, and without added phosphorus, in particular, correlates with the excessive growth of this alga in Lake Illawarra. This study has made a significant contribution to the understanding of seagrass and macroalgal growth, biomass and distribution in Lake Illawarra. This information will assist with the long-term management of macroalgal problems in Lake Illawarra.

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17

Seman-Varner, Rachel. "Ecological effects of solarization duration on weeds, microarthropods, nematodes, and soil and plant nutrients." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0012103.

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18

Hadin, Åsa. "Anaerobic digestion of horse manure : renewable energy and plant nutrients in a systems perspective." Licentiate thesis, Högskolan i Gävle, Miljöteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-22716.

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In horse keeping horse manure is produced, which can be utilized as a fertilizer or considered a waste. Horse manure constitutes a resource in terms of both plant nutrients and energy. In addition energy policies and objectives aim at replacing fossil fuels with renewable energy sources. The interest to improve resource recovery of horse manure increases due various incentives for renewable vehicle fuels, legal requirements on management of manure, and environmental impact from current horse manure management. This thesis aims at describing horse manure management in a life cycle perspective. This is made by (1) identifying factors in horse keeping affecting the possibility to use horse manure as a biogas feedstock and to recycle plant nutrients, (2) analysing factors in anaerobic digestion with influence on methane potential and biofertilizer nutrient content and (3) comparing the environmental impact from different horse manure treatment methods. Literature reviews, systematic combining, and simulations have been used as research methods. The results show that horse keeping activities such as feeding, indoor keeping, outdoor keeping and manure storage affect the amount and characteristics of horse manure and thereby also the possibilities for anaerobic digestion horse manure. Transport affects the collected amount and spreading affects loss of nutrients and nutrient recycling. Simulation results indicate the highest methane yield and energy balance from paper bedding, while straw and peat gave a higher nutrient content of the biofertilizer. The highest methane yield was achieved with a low rate of bedding, which in the cases of woodchips and paper is also preferable for plant nutrient recycling. Still, results indicate the best energy balance from anaerobic digestion with a high ratio of bedding. The environmental impact assessment indicates a reduction in global warming potential for anaerobic digestion compared to incineration or composting.
Vid hästhållning alstras hästgödsel som kan användas som växtnäring eller anses vara ett avfall. Hästgödsel utgör både en växtnäringsresurs och en energi resurs. Dessutom styr uppsatta energimål mot att förnybar energi ska ersätta fossila bränslen. Intresset för att öka resursutnyttjandet av hästgödsel ökar på grund av olika incitament för förnybara drivmedel, lagstiftning om gödselhantering och miljöpåverkan från dagens hantering av hästgödsel. I den här avhandlingen beskrivs hästgödselhantering i ett livscykelperspektiv genom att (1) identifiera olika faktorer vid hästhållningen som påverkar möjligheten att utvinna biogas ur hästgödsel och återföra näringen till jordbruksmark, (2) analysera faktorer i biogasprocessen som påverkar den specifika metanmängden och innehållet av växtnäring i gödseln och (3) jämföra olika gödselhanteringsmetoders miljöpåverkan. Metoderna i avhandlingen har varit litteraturstudier, systematisk kombination av teori och empiri samt simulering. Resultaten visar att utfodringen, om och hur hästarna hålls inomhus och utomhus och hur hästgödsel lagras påverkar mängden hästgödsel och dess egenskaper, och därmed också hur den fungerar som ett biogassubstrat. Transporterna har betydelse för hur mycket gödsel som kan samlas in och spridas, medan gödselspridningen påverkar näringsförluster och närings återföring. Resultaten från simuleringarna indikerar högst metanutbyte och bäst energibalans från papper som strömaterial, medan halm och torv gav högre växtnäringsinnehåll i biogödseln. De högsta resultaten på specifik metanmängd nåddes med låg andel strö, vilket också var positivt för växtnäringsinnehållet vid scenarierna med spån och papper. Samtidigt indikerar resultaten att en hög andel strömaterial ger den bästa energibalansen. Miljöpåverkansbedömningen indikerar att potentialen för klimatpåverkan minskar om hästgödsel behandlas i en biogasprocess jämfört med förbränning eller kompostering.

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Sousa, Adervan Fernandes. "Mineralization of nutrients and plant growth in soils irrigated with wastewater from oil extraction." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16918.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
O grande volume de Ãgua utilizado na agricultura compromete a sua disponibilidade para o consumo humano. Diante desse problema, Ã necessÃrio avaliar a utilizaÃÃo de Ãguas residuais na produÃÃo agrÃcola, como uma opÃÃo para a conservaÃÃo dos recursos hÃdricos. Ãguas residuais oriundas de campos de petrÃleo podem ser uma boa opÃÃo para irrigaÃÃo, especialmente em regiÃes de pouca e alta variabilidade de chuvas como o Nordeste brasileiro. No entanto, Ã necessÃrio avaliar os seus efeitos no solo, como acÃmulo de nutrientes e decomposiÃÃo da matÃria orgÃnica, bem como no aspecto nutricional e no crescimento das plantas. Os objetivos deste trabalho foram: i) Avaliar as mudanÃas ocorridas nos sais solÃveis e nas fraÃÃes da matÃria orgÃnica do solo e no crescimento de plantas de girassol (Helianthus annuus L.) cv. BRS 321, cultivadas em solo de textura arenosa irrigado com Ãgua residual oriunda da extraÃÃo de petrÃleo tratada por filtragem e osmose reversa; ii) Avaliar as alteraÃÃes nutricionais do girassol (Helianthus annuus) BRS 321 irrigado com Ãgua residual da extraÃÃo de petrÃleo e os efeitos sobre a produÃÃo de biomassa e de aquÃnios; e iii) Avaliar a decomposiÃÃo dos restos culturais de girassol (Helianthus annuus) cv. BRS 321 em Ãreas irrigadas com Ãgua residual da extraÃÃo de petrÃleo. O girassol foi cultivado durante trÃs perÃodos sucessivos em Ãreas irrigadas com Ãgua residual da extraÃÃo de petrÃleo tratada por filtragem (APF) e por osmose reversa (APO) ou Ãgua subterrÃnea do aquÃfero AÃu (ACA). Ao fim de cada ciclo foram determinados os valores de pH, condutividade elÃtrica (CE), a razÃo de adsorÃÃo de sÃdio (RAS) e os teores de Na, Cl, Mg, Ca, K, HCO3-, Ag, As, B, Ba, Cd, Co, Cr3+, Hg, Ni, Pb, Zn, alÃm de C nas fraÃÃes hÃmicas. Em raÃzes, parte aÃrea e aquÃnios determinaram-se os teores de N, P, K, Ca, Mg, S e Na e avaliaram-se o crescimento e o acÃmulo de biomassa. AlÃm disso, avaliou-se a decomposiÃÃo dos resÃduos da parte aÃrea das plantas de girassol. Houve alteraÃÃes nos atributos quÃmicos do solo, em destaque o acrÃscimo de sais, que foi maior nas Ãreas irrigadas com APF, e elevaÃÃo do pH, independente do tipo de Ãgua utilizado. A elevaÃÃo da salinidade e alcalinidade do solo reduziu o crescimento e o acÃmulo de biomassa das plantas. AlÃm disso, a irrigaÃÃo proporcionou alteraÃÃes nutricionais das plantas, que refletiram no crescimento e na produÃÃo de aquÃnios do girassol e na decomposiÃÃo dos resÃduos da cultura, com efeitos positivos ou negativos, conforme o tratamento da Ãgua residual. Concluiu-se que a Ãgua residual da extraÃÃo de petrÃleo utilizada na irrigaÃÃo afeta os atributos quÃmicos do solo, bem como a composiÃÃo nutricional e o desenvolvimento das plantas, principalmente quando irrigadas com a APF. AlÃm disso, a irrigaÃÃo com Ãgua residual alterou a mineralizaÃÃo dos resÃduos vegetais do girassol, mas nÃo a de decomposiÃÃo do carbono orgÃnico nas fraÃÃes hÃmicas.
The large volume of water used in agriculture compromises its availability for human consumption. Faced with this problem, it is necessary to evaluate the use of wastewater in agricultural production as an option for the conservation of water resources. Wastewater from oil fields can be a good choice for irrigation, especially in regions of low or high rainfall variability, as in the Brazilian Northeast. However, it is necessary to evaluate its effects on the soil, such as the accumulation of nutrients and decomposition of organic matter, as well as the nutritional aspect and plant growth. The aims of this study were: i) to assess the changes that take place in the soluble salts and soil organic matter fractions, and in the growth of plants of the BRS 321 cultivar of the sunflower (Helianthus annuus L.) cultivated in soil of a sandy texture and irrigated with wastewater obtained from oil extraction and treated by filtration and reverse osmosis; ii) to assess the nutritional changes in the BRS 321cultivar of the sunflower (Helianthus annuus) irrigated with wastewater from oil extraction, and the effects on biomass and achene production; and iii) to evaluate the decomposition of plant residue from the BRS 321 cultivar of the sunflower (Helianthus annuus) in areas irrigated with wastewater from oil extraction. The sunflower was grown for three successive periods in areas irrigated with wastewater from oil extraction treated by filtering (APF) and reverse osmosis (APO), or with groundwater from the AÃu aquifer (ACA). At the end of each cycle, pH values were determined, together with electrical conductivity (EC), the sodium adsorption ratio (SAR) and the levels of Na, Cl, Mg, Ca, K, HCO3-, Ag, As, B, Ba, Cd, Co, Cr3+, Hg, Ni, Pb, Zn, and of C in the humic fractions. The concentrations of N, P, K, Ca, Mg, S and Na were determined in the roots, shoots and achenes, along with growth and the accumulation of biomass. In addition, the decomposition of shoot residue from the sunflower plants was evaluated. Changes were seen in the chemical properties of the soil, highlighting an increase in salts, which was greater in the areas irrigated with APF; a rise was also seen in pH irrespective of the type of water used. The rise in soil salinity and alkalinity reduced the growth and accumulation of plant biomass. Moreover, irrigation resulted in nutritional changes in the plants, which were reflected in the growth and production of achenes, and in the decomposition of the plant residue, having positive or negative effects according to the treatment of the wastewater. It was concluded that wastewater from oil extraction used in irrigation affects the chemical properties of the soil as well as the nutritional composition and development of the plants, especially when irrigated with APF. Furthermore, irrigation with wastewater changed the mineralisation of the sunflower plant residue, but not the decomposition of the organic carbon in the humic fractions.

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20

Mulenga, Peter Chikombo. "Effects of applied micronutrients and liming on grain yield and plant composition on three ferralsols on North-Western Zambia." Thesis, University of Aberdeen, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301213.

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Review of the literature suggested possible deficiencies of micronutrients in soils of North Western Zambia. Soil analysis, pot and field experiments were employed to investigate possible deficiencies. The pot experiments investigated how raising soil pH through liming influenced extractable micronutrients and their uptake by plants. Plant Mo and Ca were positively correlated with soil pH, while Mn and Zn were inversely correlated, aggravating the zinc inadequacy on all soils and that for Mn on arenosols. Effects of liming on plant uptakes of micronutrients generally followed the same trends as those on soil extraction. Incubating the soil under grass house conditions was found to influence amounts of extractable micronutrients, increasing most times above their levels before the soil was incubated. Field experiments generally showed that applying micronutrients were beneficial to crop yield only at some sites. Grain yield variables responded variously and were most significantly correlated with overall grain yield. Soil analysis usefully predicted deficiencies of Zn for both maize and soybean. However, predictions for B and Mo were ideal for soybean than maize. Cu also seemed to have been wrongly predicted for soybean. However, plant nutrient concentration was better at predicting nutrient status in relation to grain yield, but the lower limits of the suggested optimal concentration ranges may need to be worked out again. Soybean was found to have more micronutrient latent deficiencies at majority of the sites than maize. One of the characteristics of applied micronutrients was their beneficial residual effects of crop yield. The residual benefit was also noticed on maize when the fertilisers were directly applied to soybeans a season before, suggesting a possibility of crop rotation, thus spreading the costs. Results would suggest changing the current fertiliser recommendations in the region.

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21

Tariq, Mohammad. "Effect of boron supply on the availability of nutrients in soil and uptake by radish (Raphanus sativus L.)." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363708.

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22

Pisarczyk, Elizabeth W. "The effect of garlic mustard (Alliaria petiolata) density on soil nutrient availability and microbial enzyme activity in Northwest Ohio : a gradient analysis /." Connect to full text in OhioLINK ETD Center, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=toledo1260236506.

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Thesis (M.S.)--University of Toledo, 2009.
Typescript. "Submitted as partial fulfillment of the requirements for The Master of Science Degree in Biology (Ecology-track)." "A thesis entitled"--at head of title. Bibliography: leaves 28-32.

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Smith, Erika Nichole. "Watercress (Nasturtium officinale) production utilizing brook trout (Salvelinus fontinalis) flow-through aquaculture effluent." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5150.

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Thesis (M.S.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains ix, 115 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 78-80).

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24

Pritchard, Deborah Leeanne. "Phosphorus bioavailability from land-applied biosolids in south-western Australia." Curtin University of Technology, Muresk Institute, 2005. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=16492.

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The annual production of biosolids in the Perth region during the period of this study was approximately 13,800 t dry solids (DS), being supplied by three major wastewater treatment plants. Of this, 70% was typically used as a low-grade fertiliser in agriculture, representing an annual land use area of around 1,600 ha when spread between 5 and 7 t DS/ha. Loading rates of biosolids are typically based on the nitrogen (N) requirements of the crop to be grown, referred to as the N Limiting Biosolids Application Rate (NLBAR). A consequence of using the NLBAR to calculate loading rates is that phosphorus (P) is typically in excess of plant requirement. The resultant high loading rates of P are considered in the guidelines developed for the agricultural use of biosolids in Western Australia, but lack research data specific to local conditions and soil types. Regulatory changes throughout Australia and globally to protect the environment from wastewater pollution have created a need for more accountable and balanced nutrient data. Experiments presented in this thesis were undertaken to ascertain: the percentage relative effectiveness (RE) of biosolids as a source of plant available P compared with inorganic P fertiliser; loading rates to best supply P for optimum crop growth; P loading rates of risk to the environment; and the forms of P in local biosolids. Therefore, both the agronomic and environmental viewpoints were considered. Anaerobically digested and dewatered biosolids produced from Beenyup Wastewater Treatment Plant, Perth with a mean total P content of 2.97% dry weight basis (db) were used in a series of glasshouse, field and laboratory experiments. The biosolids were sequentially fractionated to identify the forms of P present and likewise in soil samples after applying biosolids or monocalcium phosphate (MCP).
The biosolid P was predominantly inorganic (92%), and hence the organic fraction (8%) available for mineralisation at all times would be extremely low. The most common forms of biosolid P were water-soluble P and exchangeable inorganic P (66%), followed by bicarbonate extractable P (19%) and the remaining P as inorganic forms associated with Fe, Al and Ca (14%). Following the application of biosolids to a lateritic soil, the Fe and Al soil fractions sorbed large amounts of P, not unlike the distribution of P following the addition of MCP. Further investigation would be required to trace the cycling of biosolid P in the various soil pools. The growth response of wheat (Triticum aestivum L.) to increasing rates of biosolids and comparable rates of inorganic P as MCP, to a maximum of 150 mg P/kg soil was examined in the glasshouse. The percentage relative effectiveness (RE) of biosolids was calculated using fitted curve coefficients from the Mitscherlich equation: y = a (1-b exp–cx) for dry matter (DM) production and P uptake. The initial effectiveness of biosolid P was comparable to that of MCP with the percentage RE of biosolids averaging 106% for DM production of wheat shoots and 118% for shoot P uptake at 33 days after sowing (DAS) over three consecutive crops. The percentage residual value (RV) declined at similar rates for DM production in MCP and biosolids, decreasing to about 33% relative to freshly applied MCP in the second crop and to approximately 16% in the third crop. The effectiveness of biosolid P was reduced significantly compared with inorganic P when applied to a field site 80 km east of Perth (520 mm annual rainfall). An infertile lateritic podsolic soil, consistent with the glasshouse experiment and representative of a soil type typically used for the agricultural application of biosolids in Western Australia was used.
Increasing rates of biosolids and comparable rates of triple superphosphate (TSP), to a maximum of 145 kg P/ha were applied to determine a P response curve. The percentage RE was calculated for seasonal DM production, final grain yield and P uptake in wheat followed by lupin (Lupinus angustifolius L.) rotation for the 2001 and 2002 growing seasons, respectively. In the first year of wheat, the RE for P uptake in biosolids compared with top-dressed TSP ranged from 33% to 55% over the season and by grain harvest was 67%. In the second year, and following incorporation with the disc plough at seeding, the RE for P uptake by lupins in biosolids averaged 79% over the growing season compared with top-dressed TSP, and by grain harvest the RE was 60%. The residual value (RV) of lupins at harvest in biosolids compared with freshly applied TSP was 47%. The non-uniform placement of biosolids (i.e. spatial heterogeneity) was primarily responsible for the decreased ability of plant roots to absorb P. The P was more effective where biosolids were finely dispersed throughout the soil, less so when roughly cultivated and least effective when placed on the soil surface without incorporation. The RE for grain harvest of wheat in the field decreased from 67% to 39% where biosolids were not incorporated (i.e. surface-applied). The RE could also be modified by factors such as soil moisture and N availability in the field, although it was possible to keep these variables constant in the glasshouse. Consequently, absolute values determined for the RE need to be treated judiciously. Calculations showed that typical loading rates of biosolids required to satisfy agronomic P requirements of wheat in Western Australia in the first season could vary from 0 to 8.1 t DS/ha, depending on soil factors such as the P Retention Index (PRI) and bicarbonate available P value.
Loading rates of biosolids were inadequate for optimum P uptake by wheat at 5 t DS/ha (i.e. 145 kg P/ha) based on the NLBAR on high P sorbing soils with a low fertiliser history (i.e. PRI >15, Colwell bicarbonate extractable P <15 mg P/kg). On soils of PRI <2 mL/g however, biosolids applied at identical loading rates would result in high concentrations of available P. Further work on sites not P deficient would be necessary to validate these findings on farmed soils with a regular history of P fertiliser. The sieving of soil samples used in the field experiment to remove stones and coarse organic matter prior to chemical analysis inadvertently discarded biosolids particles >2 mm, and thus their was little relationship between soil bicarbonate extractable P and P uptake by plants in the field. The risk of P leaching in biosolids-amended soil was examined over a number of different soil types at comparable rates of P at 140 mg P/kg (as either biosolids or MCP) in a laboratory experiment. Given that biosolids are restricted on sites prone to water erosion, the study focussed on the movement of water-soluble P by leaching rather than by runoff of water-soluble P and particulate P. In general the percentage soluble reactive P recovered was lower in soils treated with biosolids than with MCP, as measured in leachate collected using a reverse soil leachate unit. This was particularly evident in acid washed sand with SRP measuring 14% for biosolids and 71% for MCP, respectively, although the differences were not as large in typical agricultural soils. Specific soil properties, such as the PRI, pH, organic carbon and reactive Fe content were negatively correlated to soluble reactive P in leachate and thus reduced the risk of P leaching in biosolids-amended soil.
Conversely, the total P and bicarbonate extractable P status of the soils investigated were unreliable indicators as to the amount of P leached. On the basis of the experiments conducted, soils in Western Australia were categorised according to their ability to minimise P enrichment and provide P necessary for crop growth at loading rates determined by the NLBAR. Biosolids applied at the NLBAR to soils of PRI >2mL/g with reactive Fe >200 mg/kg were unlikely to necessitate P loading restrictions. Although specific to anaerobically digested biosolids cake applied to Western Australian soils, the results will be of relevance to any industry involved in the land application of biosolids, to prevent P contamination in water bodies and to make better use of P in crop production.

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25

Mbaya, Andre MK. "Impact of urine diversion on Biological Nutrients Removal Activated Sludge Wastewater Treatment Plant (BNRAS WWTP)." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/10579.

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This experimental investigation was started to study the impacts urine separated WW [Wastewater] can have on BNRAS WWTPs [Biological Nutrient Removal Activated Sludge Wastewater Treatment Plants] with a UCT and a JHB configuration.

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26

Nxawe, Sinovuyo. "Effects of regulating hydroponic, solution temperature on plant growth, accumulation of nutrients and other metabolites." Thesis, Cape Peninsula University of Technology, 2011. http://hdl.handle.net/20.500.11838/843.

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Thesis (Dissertation (Masters Degree(Horticultural Science))--Cape Peninsula University of Technology, 2011
The experiment was conducted with the objectives of establishing effects of regulating hydroponic solution temperatures on the chlorophyll content and photosynthesis processes, accumulation of anthocyanins and flavonoids, nutrient uptake and growth and development of pregnant onion (Ornithogalum longibracteatum L.) in the glasshouse during winter periods in 2009 and 2010. The plants were exposed to four hydroponic solution temperatures (control (10 - 15°C), 26°C, 30°C and 34°C). The treatments were arranged in a complete randomized design.Results from this study conducted in the glasshouse in 2009 and verified in 2010 showed that photosynthesis rate (A) and the gas exchange parameters [stomata conductance (gs), intercellular CO2 concentration (Ci) and transpiration (E)] were significantly increased by elevating the hydroponic solution temperatures to 26-30°C compared with the control and then decreased significantly at 34°C. Furthermore, increasing hydroponics solution temperature from 26°C to 34°C significantly increased the levels of flavonoids and anthocyanins in roots, bulbs, shoots and flowers of O. longibracteatum in both years 2009 and 2010.Warming of the hydroponic solution to 26, 30 and 34oC significantly increased the uptake of (N, P, K, Ca, Mg, S, Na Fe, Cu Zn, Mn and B and Mo) in organs of O. longibracteatum (root, bulbs shoot, and whole plant) in 2009 and verified in 2010. The control treatments 10/15°C (day/night) had the lowest uptake of most nutrients.Results from the two years study also showed that plant growth parameters such as number of bulbs per plant, bulb circumference, flower stalk length, flower length, and dry and fresh weights of root, bulb, shoot and flower respectively were significantly increased by warming the hydroponic solution. Elevating the hydroponic solution temperature to a range of 26 - 30°C induced best growth and produced the highest dry matter yield in O. longibracteatum under glasshouse conditions whereas further increase to 34°C resulted in reduced growth and yield.

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Nicholls, Ann M. "Influences of Environmental Variability, Genetics and Plant Size on Variation in Sexual and Clonal Reproduction and Allocation of Resources in Three Wetland Plant Species." Cleveland State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=csu1305559126.

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Smith, Dian H. (Dian Helen). "Nutrient Effects on Autofragmentation of Myriophyllum Spicatum L." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc279354/.

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A 2 x 2 factorial design investigated effects of sediment nitrogen and water potassium levels on autofragment production. Reduced nitrogen levels significantly increased autofragment production whereas potassium levels did not significantly alter production. Up to 50% of autofragment production abscised from parent plants grown under low nitrogen conditions compared to 12% or less under high nitrogen conditions.

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Siraj-Ali, Mahmoud Saleh. "Influence of nutrient solution pH on the availability and uptake of plant nutrients and growth of Chrysanthemum morifolium 'Bright Golden Anne' in hydroponic culture /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487264603216396.

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30

Adams, Zachry Clay Adams James F. "Comparison of broiler litter, broiler litter ash with reagent grade materials as sources of plant nutrients." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Fall/Thesis/ADAMS_ZACHRY_50.pdf.

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Queiroz, Renan Batista. "Adubação com enxofre, nitrogênio, cálcio e potássio afetando a interação entre Tuta absoluta e o tomateiro." Universidade Federal de Viçosa, 2011. http://locus.ufv.br/handle/123456789/3917.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The nutrients used for plant fertilization affect their susceptibility to insect herbivores. Among the major pests of tomato in the world is a leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). Thus, the aim of this study was to determine the influence of plant fertilization with calcium, sulfur, nitrogen and potassium in reproduction, growth, survival and damage of T. absoluta. This study was conducted in a greenhouse. The experimental design was randomized blocks with nine treatments and five replications. The treatments consisted of fertilization levels of deficiency and excess calcium, sulfur, nitrogen and potassium. One treatment with normal fertilization was established beyond these levels. The eggs from T. absoluta were transferred for the leaves of tomato a month after the start of the experiment. The number of surviving insects, the developmental stage of insects and the number of mines per leaf were evaluated daily. The contents of nutrients were determined in leaves of tomato. Among the nutrients studied, only the doses of sulfur and nitrogen fertilizer used in the affected T. absoluta. The reproduction of T. absoluta was lower in plants with normal fertilization, higher the mortality of larvae and these plants suffered less damage than those with nutritional deficiency. The maximum reproductive performance of T. absoluta occurred in plants with nutritional deficiency. The plants with higher levels of nutrients in leaves were less susceptible to T. absoluta.
Os nutrientes utilizados na adubação das plantas afetam sua suscetibilidade aos insetos herbívoros. Entre as principais pragas do tomateiro no mundo está a traça Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). Assim, o objetivo deste trabalho foi determinar a influência da adubação das plantas com cálcio, enxofre, nitrogênio e potássio na reprodução, desenvolvimento, sobrevivência e danos de T. absoluta. Este trabalho foi conduzido em casa de vegetação. O delineamento experimental foi em blocos casualizados com nove tratamentos e cinco repetições. Os tratamentos foram constituídos de níveis de adubação em deficiência e em excesso de cálcio, enxofre, nitrogênio e potássio. Além destes níveis estabeleceu-se um tratamento com adubação normal. Um mês após o início do experimento, foram transferidos ovos de T. absoluta para as folhas do tomateiro. Diariamente avaliaram-se o número de insetos sobreviventes, o estádio de desenvolvimento dos insetos e o número de minas por folha. Foram determinados os teores de nutrientes nas folhas do tomateiro. Dos nutrientes estudados apenas as doses de enxofre e de nitrogênio usadas na adubação afetaram T. absoluta. Nas plantas com adubação normal foi menor a reprodução de T. absoluta, maior a mortalidade larval e estas plantas sofreram menores danos do que aquelas com deficiência nutricional. O máximo desempenho reprodutivo de T. absoluta ocorreu em plantas com deficiência nutricional. As plantas com maiores teores de nutrientes nas folhas foram menos suscetíveis a T. absoluta.

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32

Wasley, Jane. "The effect of climate change on Antarctic terrestrial flora." School of Biological Sciences - Faculty of Science, 2004. http://ro.uow.edu.au/theses/275.

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Climate change is expected to affect the high latitudes first and most severely, rendering Antarctica one of the most significant baseline environments for the study of global climate change. The indirect effects of climate warming, including changes to the availability of key environmental resources, such as water and nutrients, are likely to have a greater impact upon Antarctic terrestrial ecosystems than the effects of fluctuations in temperature alone. Water availability is the focus in this thesis for two main reasons; firstly, there is a wealth of evidence to suggest water is currently limiting to Antarctic plant distributions and productivity, and secondly, availability of this key resource is predicted to change with the onset of climate change. Nutrient availability is a second variable considered in this work, as there is evidence to suggest that nutrients also play a role in determining plant species distributions, and changes to nutrient balance and turnover rates are also expected in response to climate change. This work was conducted in the floristically important Windmill Islands region of East Antarctica, with the three Windmill Islands moss species Bryum pseudotriquetrum, Ceratodon purpureus and Grimmia antarctici forming its focus. A combination of field ecology, ecophysiology and laboratory studies were used to determine fine-scale patterns of present species distributions and their relationship to naturally occurring water and nutrient resource gradients, the impact of increased water and nutrients on a range of cryptogamic communities, and tolerance of desiccation biological profiles. A survey-based approach was used to determine species level patterns in bryophyte species distributions, and identify correlations with resource availability. Ten replicate transects, along community gradients, from pure bryophyte stands, through transitional moribund bryophyte zones, to lichen-dominated communities, were surveyed at two sites. The physical environment at each site was characterised by measurement of site soil properties, along with individual transect aspects and slopes. To determine the relationship between resource gradients and community patterns water and nutrient availability, along with a range of plant biochemistry measures indicative of the growth environment, were measured using a series of quadrats along each transect. Percent abundance for each species and/or vegetation category was determined for each quadrat by microscopic examination of field samples. The community gradient, covering the entire ecological range of past and present bryophyte occupation, was found to be accompanied by resource gradients that operated in opposing directions. Pure bryophyte communities existed under conditions of high water availability and low nutrient availability. Crustose lichen-dominated communities persisted under opposing environmental conditions, of low water availability and high nutrient availability. Grimmia antarctici dominated the wettest habitats but its distribution extended into the dry moribund zones, albeit in low levels of abundance. Bryum pseudotriquetrum occurred in consistent levels of abundance across the entire gradient, whilst C. purpureus was restricted to the driest habitats. Live bryophyte material was found to occur in moribund turf, supporting the potential for bryophyte regeneration under a future wetter climate. Regenerating turf showed potential to support high species diversity, as all four bryophytes survive in this zone. To investigate the likely impacts of a wetter climate on Antarctic terrestrial communities, four cryptogamic communities, pure bryophyte, moribund bryophyte, crustose and fructicose lichen-dominated communities were subject to a multi-season manipulative field experiment. Within each community type, eight replicate quadrats received increased water and/or nutrient availability over two consecutive summer seasons. A range of physiological and biochemical measurements were conducted in order to quantify the community response to the treatments and determine the extent of any nutrient and water limitation. Few multi-season manipulative field experiments have been conducted in continental Antarctica. Whilst an overall increase in productivity in response to water and nutrient additions was supported, productivity appeared to respond more strongly to nutrient additions than to water additions. Pure bryophyte and fructicose lichen communities also showed stronger positive responses to additions, identifying some communities that may be better able to adapt and prosper under the ameliorating conditions associated with a warmer, wetter future climate. Using a range of morphological, biochemical and physiological techniques, biological profiles related to desiccation tolerance were developed for the three bryophyte study species, providing measures of relative abilities to avoid, tolerate, recover from and survive desiccation. Ceratodon purpureus showed good desiccation avoidance characteristics, its photosynthetic efficiency remained high at low water contents and it was lipid rich, suggesting that this species is well adapted to survive a drying climate. Bryum pseudotriquetrum is also likely to survive drier conditions, as this species showed good desiccation avoidance, had a plastic response to desiccation, and contained stachyose, which is likely to assist in its survival of desiccation events. Conversely, G. antarctici showed poor desiccation avoidance, as photosynthetic efficiency required highest water contents and it contained few protective substances, this species is therefore least likely to survive a drying environment. This study provides a baseline from which future changes to the Windmill Islands cryptogamic communities can be monitored. A baseline incorporating fine-scale bryophyte species patterns is particularly useful, as this component of the cryptogamic community is likely to be highly sensitive to even small shifts in water availability and detection of change is likely to be more sensitive at fine- rather than broad-scales. Both water and nutrient resource availability was found to underlie regional bryophyte species distributional patterns. The dynamics of the Windmill Islands flora is therefore likely to shift in response to climate change as the availability of these key resources is altered. Under a wetter future climate, productivity is overall likely to increase but only certain cryptogamic communities are likely to thrive. Regeneration of moribund bryophytes appears likely only if the future moisture regime creates consistently moist conditions. Bryum pseudotriquetrum is most likely to survive both a drying climate and also a fluctuating climate, which is a highly likely scenario for the region. Under a drier climate, the Antarctic endemic, G. antarctici, is likely to be most adversely affected, as it dominates only the wettest communities and generally shows poor tolerance of desiccation. Conservation issues are therefore raised for this species, if the current drying trend continues, creating overall biodiversity concerns.

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33

Guan, Dong-sheng. "A study of primary productivity and nutrients in the grassland, fernland and scrubland of Hong Kong /." [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13616286.

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34

Reynolds, Amanda Christine. "Geochemical Investigations of Mineral Weathering: Quantifying Weathering Intensity, Silicate versus Carbonate Contributions, and Soil-Plant Interactions." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194448.

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This study is the geochemical examination of mineral weathering and its path from hinterland, through sediment deposition and pedogenesis, to its dissolution and eventual uptake into plants or precipitation as carbonate minerals. The three papers examine the rate and character of carbonate and silicate mineral weathering over a wide range of climatic and tectonic regimes, time periods, and lithologies, and focus on very different questions. Examination of the 87Sr/86Sr ratios of architectural ponderosa pine in Chaco Canyon, New Mexico confirms a societally complex style of timber procurement from the 10th to the 12th centuries. In El Malpais National Monument, New Mexico, we measured the 87Sr/86Sr ratios in local bedrock and soils and compared them to the leaf/wood cellulose of four conifers (Pinus ponderosa, Pinus edulis, Juniperus monosperma, Juniperus scopulorum), a deciduous tree (Populus tremuloides), three shrubs (Chrysothamus nauseosus, Fallugia paradoxa, Rhus trilobata), and an annual grass (Bouteloua gracilis) and a lichen (Xanthoparmelia lineola). We found that plant 87Sr/86Sr ratios covaried with variations in plant physiognomy, life history, and rooting depth. In addition, the proportion of atmospheric dust and bedrock mineral contributions to soil water 87Sr/86Sr ratios varied predictably with landscape age and bedrock lithology. On the Himalayan floodplain, soils and paleosol silicate weathering intensities were measured along a climatic transect and through time. Overall, carbonate weathering dominates floodplain weathering. But, periods of more intense silicate weathering between 9 - 2 Ma, identified in soil profile and in the 87Sr/86Sr ratios of pedogenic carbonates, appear to be driven by changes in tectonic, rather than climatic, regime. All three papers are good examples of how 87Sr/86Sr isotopic tracer studies can shed light on pedogenic formation rates and internal processes. The complexity of each system warns against generalizations based on just one locale, one species or lithology, or a few isotopic ratios.

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Nordin, Annika. "Ammonia based sanitation technology : safe plant nutrient recovery from source separated human excreta /." Uppsala : Department of Biometry and Engineering, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/10626290.pdf.

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36

Gebhardt, Martha Mary. "Soil Amendment Effects on Degraded Soils and Consequences for Plant Growth and Soil Microbial Communities." Thesis, The University of Arizona, 2015. http://hdl.handle.net/10150/556614.

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Human activities that disrupt soil properties are fundamentally changing ecosystems. Soil degradation decreases microbial abundance and activity, leading to changes in nutrient availability, soil organic matter, and plant growth and establishment. Land use and land cover change are widespread and increasing in semiarid regions of the southwestern US, which results in reductions of native plant and microbial abundance and community diversity. Here we studied the effects of soil degradation and amendments (biochar and woodchips) on microbial activity, soil carbon and nitrogen availability, and plant growth of ten semi-arid plants species native to the southwestern US. Results show that woodchip amendments result in poor overall plant growth, while biochar amended soils promoted plant growth when soil quality was reduced. Additionally, amendments had a strong influence on microbial activity, while the presence and species identity of plants did not. Biochar amended soils led to increases in the potential activities of enzymes involved in the degradation of carbon, nitrogen, and phosphorus rich substrates. Woodchips, caused an increase of potential activity in enzymes involved in the degradation of sugar and proteins. These results show that microbes and plants respond differently to soil treatments and suggest that microbial responses may function as earlier indicators of the success of re-vegetation attempts.

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Towler, Melissa J. "Effects of inoculum density, carbon concentration, and feeding scheme on the growth of transformed roots of Artemisia annua in a modified nutrient mist bioreactor." Digital WPI, 2005. https://digitalcommons.wpi.edu/etd-dissertations/269.

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Previous work has shown that despite the lack of oxygen limitation, transformed roots of Artemisia annua had lower biomass productivity in a nutrient mist bioreactor than in a liquid-phase bubble column reactor where the roots demonstrated metabolic signs of oxygen stress. Mathematical modeling suggested that the roots were too sparsely packed to capture mist particles efficiently and to achieve high growth rates. In this study, higher packing fractions were tested, and the growth rate increased significantly. Similarly, higher sucrose concentrations increased the growth rate. Growth kinetics for 2, 4, and 6 days showed an unexpected decrease or stationary growth rate after only 4 days for both 3% and 5% sucrose feeds. Residual media analyses indicated that carbon was not exhausted, nor were other major nutrients including phosphate. Increasing the misting frequency such that the total amount of carbon delivered from a 3% sucrose feed was equivalent to that delivered in a 5% sucrose feed showed that growth was affected by the modified cycle. These studies showed that both the concentration of carbon source and alteration of misting frequency can significantly increase growth rates of hairy roots in mist reactors.

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Guan, Dong-sheng, and 管東生. "A study of primary productivity and nutrients in the grassland, fernland and scrubland of Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31233569.

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Woldetsadik, Kebede. "Shallot (Allium cepa var. ascolonicum) responses to plant nutrients and soil moisture in a sub-humid tropical climate /." Alnarp : Dept. of Crop Science, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/a367.pdf.

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Hammer, Erin L. "Effects of garlic mustard (Alliaria petiolata) on soil nutrient dynamics and microbial community function and structure." Connect to full text in OhioLINK ETD Center, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=toledo1241126072.

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Thesis (M.S.)--University of Toledo, 2009.
Typescript. "Submitted as partial fulfillment of the requirements for The Master of Science Degree in Biology (Ecology-track)." "A thesis entitled"--at head of title. Bibliography: leaves 44-55.

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Saha, Amartya Kumar. "The Role of Spatiotemporal Heterogeneity in Water and Nutrient Pools in Everglades Plant Community Diversity and Function." Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_dissertations/211.

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Spatial and temporal heterogeneity of water and nutrient pools is closely associated with the existence of different plant communities in hydrologically-controlled ecosystems such as the Everglades. These various communities differ in their flooding and fire tolerances as well as nutrient requirements. Upland plant communities are of particular ecological significance since they have high biodiversity and provide habitat to terrestrial fauna, yet comprise less than 10 % of the total area. Restoration and maintenance of such communities requires an understanding of their water and nutrient requirements. Chapter 2 compares water source utilization in hammocks and pine rocklands on the Miami Rock Ridge using stable isotopes of water. Hammocks do not flood, while adjacent pinelands may flood between 2-3 months. In the wet season, hammocks were found to use phosphorus (P) rich soilwater, a local pool of water and nutrients while pineland plants primarily relied upon groundwater, the regional pool. Access to a rich pool of P in the oligotrophic Everglades was associated with higher community-level foliar P concentration in hammocks. However in the dry season, hammocks utilized groundwater, which suggests sensitivity to extended droughts. Chapter 3 compares the hammock (upland or head) and swamp forests (lowland or tail) on tree islands in the Shark River Slough. Uplands were associated with P-rich soilwater uptake in the wet season, with regional water uptake in the dry season. Accordingly, tree island heads are rich in foliar P and thereby P-hotspots in the Everglades. Foliar nutrient concentrations can thus indicate limiting nutrient availability in the Everglades. Chapter 4 looks at how leaf phenology patterns are tied to water and nutrient pools. Leaf fall in ridge hammocks is associated with high foliar carbon isotope values over the dry season, which is not the case for tree island hammocks. However, in some species, high levels of foliar nitrogen are also associated with high foliar C13 values indicating stomatal limitation of photosynthesis. Growing season for most hammock species is the wet season coinciding with high availability of P, as reflected in high foliar P in this season. Linking water sources to foliar nutrients elucidates roles of water and nutrient pools in leading to different plant communities within an ecosystem.

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Ribeiro, Maria da Saúde de Sousa. "Ecofisiologia e produtividade de alecrim pimenta nas condições edafoclimáticas do Maciço de Baturité, Ceará." reponame:Repositório Institucional da UFC, 2015. http://www.repositorio.ufc.br/handle/riufc/20224.

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RIBEIRO, Maria da Saúde de Sousa. Ecofisiologia e produtividade de alecrim pimenta nas condições edafoclimáticas do Maciço de Baturité, Ceará. 2015. 89 f. Dissertação (Mestrado em Engenharia Agrícola)-Universidade federal do Ceará, Fortaleza, 2015.
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The medicinal plants are included within the wide diversity of the Maciço de Baturité ecosytem and they are an important component of traditional medicine of this region. However, scientific information that may contribute to the increase in the cultivation of these plants are still rare, particularly at conditions of the State of Ceará. The overall objective of this project is to evaluate the development and the production of alecrim pimenta (Lippia origanoides) at conditions of Maciço de Baturité, Ceará. Two experiments were conducted, the first during the dry season of 2013 (August to November) and the second during the rainy season of 2014 (February to May). The experiment was corned out in completely randomized design with split plots, being the plots defined by two seasons (drought and rainy), the subplot formed by light conditions (greenhouse and full sun), and the subsubplots formed by four evaluation times (0, 40, 80 and 120 days after transplanting). Five replications were used, each one represented by a pot of 20 L containing a plant. The following variables were evaluated: leaf area, plant height, stem diameter, dry matter production, leaf gas exchange, chlorophyll content, mineral nutrients, organic solutes, and essential oils. The alecrim pimenta grows well in the Baturité region, with yields of biomass and essential oil similar to those observed in other studies. The cultivation in greenhouse (50% of solar radiation) changed the pattern of development of alecrim pimenta, resulting in plants with better overall appearance, taller, with larger leaves, higher specific leaf area, less developed root system, and lower root/shoot ratio, regardless of the season of cultivation. The production of dry biomass of leaves and total did not differ between the two environments (light conditions) after 120 days cultivation, regardless of the period of year. During the drought season there was a strong influence of the light condition on stomatal conductance and transpiration, with the values being lower in full sun environment, suggesting stomatal sensitivity to climate conditions in this species. Plants grown in greenhouse showed, in general, higher levels of nutrients and nitrogen compounds (N-aminossolúveis), compared to plants under full sunlight, regardless of the cropping season.
Dentre os vegetais que compõem ampla diversidade do Maciço de Baturité se inserem as plantas medicinais, sendo estas, principais componentes da medicina tradicional. No entanto, informações científicas que possam contribuir para o incremento do cultivo dessas plantas ainda são raras, particularmente nas condições edafoclimáticas do Estado do Ceará. Objetivou-se com o presente trabalho, avaliar o desenvolvimento e o potencial produtivo do alecrim pimenta (Lippia origanoides) nas condições edafoclimáticas do Maciço de Baturité, Ceará. Foram realizados dois experimentos, sendo o primeiro durante o período seco de 2013 (agosto a novembro) e o segundo durante o período chuvoso de 2014 (fevereiro a maio). O experimento foi conduzido seguindo um delineamento inteiramente casualizados com parcelas subsubdivididas, sendo as parcelas definidas pelas duas estações (seca e chuvosa), as subparcelas formadas pelas condições de luminosidade (telado e pleno sol), e as subsubparcelas pelas quatro épocas de avaliação (0, 40, 80 e 120 dias após o transplantio). Foram utilizadas cinco repetições, sendo cada repetição representada por um vaso de 20 litros contendo uma planta. Foram avaliadas as seguintes variáveis: área foliar, altura da planta, diâmetro do caule, massa seca dos diferentes órgãos vegetais, trocas gasosas, teores de clorofila, teores de minerais, solutos orgânicos e rendimento do óleo essencial. O alecrim pimenta desenvolveu-se bem na região do Maciço de Baturité, com produtividades de biomassa e de óleo essencial similares às observadas em outros estudos. O cultivo em telado alterou o padrão de desenvolvimento do alecrim pimenta, resultando em plantas com melhor aparência geral, mais altas, com folhas maiores, maior área foliar específica, menor desenvolvimento do sistema radicular e menor relação raiz/parte aérea, independentemente da época de cultivo. A produção de massa seca de folhas e total não diferiu entre os dois ambientes após 120 dias de cultivo, independentemente do período do ano. Houve forte influência do ambiente de cultivo no período seco, sobre a condutância estomática e a transpiração, com os valores sendo menores no ambiente a pleno sol, sugerindo a sensibilidade estomática da espécie às condições atmosféricas do período. As plantas cultivadas em telado apresentaram, de forma geral, maiores teores de nutrientes minerais e de compostos nitrogenados (N-aminossolúveis), em comparação às plantas submetidas a pleno sol, independente do época de cultivo.

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Sgobi, Murilo Augusto [UNESP]. "Acúmulo de matéria seca, extração e exportação de nutrientes de cultivares de trigo inoculados com Azospirillum brasilense." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/148817.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Inocular sementes de trigo com a bactéria Azospirillum brasilense pode propiciar a fixação biológica de nitrogênio (FBN), porém tem sido observado efeito mais pronunciado desta inoculação no crescimento inicial de plantas, assim, com o sistema radicular mais desenvolvido, a absorção de nutrientes e água pode ser maior. Com isso, o crescimento, produtividade e exportação de nutrientes da cultura do trigo podem ser maiores, porém a resposta a esta inoculacao pode variar conforme a afinidade da bacteria com os cultivares de trigo. Dessa forma, objetivou-se avaliar o acúmulo de matéria seca e extração de nutrientes em estádios fenológicos, exportação de nutrientes pelos grãos, componentes de produção e produtividade de grãos de cultivares de trigo inoculados ou não com Azospirillum brasilense. O experimento foi desenvolvido em Selvíria - MS, em um Latossolo Vermelho Distroférrico de textura argilosa, em sistema plantio direto. O delineamento experimental foi em blocos ao acaso com quatro repetições, com os tratamentos dispostos em esquema fatorial 3 x 2, sendo três cultivares de trigo (CD 116, IPR CATUARA TM e IAC 385), com ou sem inoculação de sementes por Azospirillum brasilense (300 ml ha-1 do produto, com estirpes Abv5 e Abv6 (garantia de 2x108 UFC mL-1). Procedeu-se também a análise de regressão em esquema de parcela subdividida com quatro repetições, em que as parcelas foram constituídas pelos seis tratamentos descritos acima, e as subparcelas no tempo, por sete épocas de coletas de plantas (antes do afilhamento, afilhamento e antes da adubação nitrogenada de cobertura, folha bandeira, emborrachamento, florescimento, grão pastoso e maturação fisiológica), para o acúmulo de matéria seca e extração de nutrientes. A inoculação com Azospirillum brasilense propiciou maior índice de clorofila foliar (ICF) e acúmulo de matéria seca de raízes, independentemente do cultivar de trigo. Os cultivares de trigo extraíram quantidades totais de nutrientes semelhantes, porém a extração por tonelada de grãos produzida foi diferenciada para K, Mg, S, B, Cu, Mn e Zn. A extração de nutrientes total ou por tonelada de grãos produzida em ordem decrescente foi de N>K>P>S>Ca>Mg>Fe>Mn>Zn≥B>Cu, com ou sem a inoculação com Azospirillum brasilense. As maiores exportações totais de K, Ca, Mg, S e Mn foram obtidas sem a inoculação com Azospirillum brasilense, entretanto, esta bactéria diazotrófica proporcionou maiores exportações de N, P, K, Ca e Mg por tonelada de grãos produzida e de Zn total. As maiores exportações relativas (acima de 50% do que é extraído) foram de Zn, Cu, P, N e B e de Mg apenas com a inoculação. O cultivar CD 116 foi o mais produtivo e que propiciou as maiores exportações totais de nutrientes, apesar da menor absorção de K, Mg, S, Cu, Mn e Zn por grãos produzido em relação aos demais cultivares. A inoculação com Azospirillum brasilense interfere de forma diferenciada nos cultivares de trigo, sendo que o cultivar CD 116 proporcionou a maior produtividade de grãos quando inoculado.
Wheat seeds inoculated with Azospirillum brasilense bacteria can provide biological nitrogen fixation (BNF), but has been observed more pronounced effect of this inoculation in the initial plant growth (phytohormonal effect), thereby, with the further development of root system, the nutrients and water uptake may be greater. Thus, the growth, productivity and nutrients removal from the wheat crop may be higher, but the response to this inoculation may vary according to the affinity of the bacterium with the wheat cultivars. The aim of this study was to evaluate the dry matter accumulation the accumulation of dry matter and nutrients uptake at different growth stages, nutrients export by grains, yield components and grains yield of wheat cultivars inoculated or not with Azospirillum brasilense. The experiment was conducted in Selvíria - MS, in a distroferric Oxisol clayey in no-till system. The experimental design was a randomized block with four replications, with the treatments arranged in a factorial 3 x 2, with three wheat cultivars (CD 116, IPR CATUARA TM and IAC 385) with or without seed inoculation by Azospirillum brasilense (300 ml ha-1 product with strains Abv5 Abv6 (2x108 guarantee UFC mL-1). Also proceeded regression analysis in a split plot scheme with four replications, where the plots were the six treatments described above, and the subplots, seven plants collections seasons (before of tillering, tillering and before nitrogen topdressing, leaf flag, booting, flowering, doughy grain and physiological maturity), for the accumulation of dry matter, extraction and export of nutrients. Azospirillum brasilense inoculation provided greater leaf chlorophyll index (LCI) and accumulation of roots dry matter, regardless of the wheat cultivar. The wheat cultivars uptake similar total amounts of nutrients, but the uptake per ton of grain produced was differentiated for K, Mg, S, B, Cu, Mn and Zn. Total nutrient extraction or per ton of grain produced in descending order was N>K>P>S>Ca>Mg>Fe>Mn>Zn>B>Cu, with or without inoculation with Azospirillum brasilense. The highest total removal of K, Ca, Mg, S and Mn were obtained without inoculation with Azospirillum brasilense; however, this diazotrophic bacterium provided higher removal of N, P, K, Ca and Mg per ton of grain produced and Zn total. The highest relative removal (above 50% that is uptake) was the Zn, Cu, P, N and B and Mg only with inoculation. The CD 116 cultivar was the most productive and provided the highest total nutrients removal, despite the lower uptake of K, Mg, S, Cu, Mn and Zn by grains produced in relation to the other cultivars. The inoculation with Azospirillum brasilense interferes differently in wheat cultivars, and cultivar CD 116 obtained the highest grain yield when inoculated.

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Sgobi, Murilo Augusto. "Acúmulo de matéria seca, extração e exportação de nutrientes de cultivares de trigo inoculados com Azospirillum brasilense /." Ilha Solteira, 2016. http://hdl.handle.net/11449/148817.

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Orientador: Marcelo Carvalho Minhoto Teixeira Filho
Resumo: Inocular sementes de trigo com a bactéria Azospirillum brasilense pode propiciar a fixação biológica de nitrogênio (FBN), porém tem sido observado efeito mais pronunciado desta inoculação no crescimento inicial de plantas, assim, com o sistema radicular mais desenvolvido, a absorção de nutrientes e água pode ser maior. Com isso, o crescimento, produtividade e exportação de nutrientes da cultura do trigo podem ser maiores, porém a resposta a esta inoculacao pode variar conforme a afinidade da bacteria com os cultivares de trigo. Dessa forma, objetivou-se avaliar o acúmulo de matéria seca e extração de nutrientes em estádios fenológicos, exportação de nutrientes pelos grãos, componentes de produção e produtividade de grãos de cultivares de trigo inoculados ou não com Azospirillum brasilense. O experimento foi desenvolvido em Selvíria - MS, em um Latossolo Vermelho Distroférrico de textura argilosa, em sistema plantio direto. O delineamento experimental foi em blocos ao acaso com quatro repetições, com os tratamentos dispostos em esquema fatorial 3 x 2, sendo três cultivares de trigo (CD 116, IPR CATUARA TM e IAC 385), com ou sem inoculação de sementes por Azospirillum brasilense (300 ml ha-1 do produto, com estirpes Abv5 e Abv6 (garantia de 2x108 UFC mL-1). Procedeu-se também a análise de regressão em esquema de parcela subdividida com quatro repetições, em que as parcelas foram constituídas pelos seis tratamentos descritos acima, e as subparcelas no tempo, por sete épocas de c... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre

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Rodrigues, Marcelo Antonio. "Crescimento e marcha de absorção de nutrientes de crisântemo (Dendranthema grandiflora, Tzvelev.) cultivado em vaso." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-17122013-125254/.

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O crisântemo cultivado em vaso é um dos produtos floríferos mais vendidos na floricultura brasileira, possuindo grande diversidade de cores, formas e tamanhos de inflorescências, além de possuir alta durabilidade após a colheita. Para tanto, é necessário o atendimento das exigências nutricionais da planta para possibilitar expressar seu potencial ornamental. Os objetivos deste trabalho foram analisar o crescimento da planta e caracterizar a marcha de absorção de nutrientes no cultivo em vaso do crisântemo, variedade cultivada ,,Fine Time\". O experimento foi realizado na estufa climatizada do Setor de Floricultura do Colégio Politécnico da UFSM, Santa Maria - RS, no período de setembro a dezembro de 2012. O delineamento experimental foi inteiramente casualizado com oito tratamentos e seis repetições. As plantas foram coletadas e analisadas em intervalos que variaram de 7 a 14 dias dependendo da fase de desenvolvimento da planta. Os parâmetros de crescimento avaliados foram: comprimento das hastes, folhas e de raízes; número de folhas, raízes, brotações, botões florais e de inflorescências; largura e área das folhas; massa de matéria seca das folhas, raízes; botões florais; inflorescências, hastes e das plantas. Em relação aos nutrientes foi analisado teor, acúmulo e marcha de absorção de N, P, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn nas raízes, folhas, hastes, botões florais e inflorescências. Os parâmetros comprimento das hastes e raízes, número de folhas e raízes, massa de matéria seca de planta, haste e raiz foram crescentes em função do tempo, tendendo a estabilidade no final do ciclo produtivo. Os parâmetros comprimento e largura das folhas decrescem em função do tempo de cultivo. A ordem decrescente de acúmulo de massa de matéria seca dos órgãos foi: folhas > hastes > raízes > inflorescências > botões florais. A necessidade de N, P, S e Cu é semelhante durante a fase vegetativa e de florescimento. A necessidade de K, Mn e Zn nas plantas é maior na fase de florescimento. A necessidade de Ca, B, Fe e Mg nas plantas é maior na fase vegetativa. A necessidade dos macronutrientes durante a fase vegetativa e de florescimento da planta segue, respectivamente, a seguinte ordem de grandeza: Ca > Mg > N > S > P > K; e K > P > S > N > Mg > Ca. A necessidade dos micronutrientes durante a fase vegetativa e de florescimento da planta segue, respectivamente, a seguinte ordem decrescente de grandeza: B > Fe> Cu > Zn > Mn; e Mn > Zn > Cu > Fe > B. A sequência decrescente do acúmulo de nutrientes nas plantas de crisântemo em função do tempo foi: N > K > P > Ca > S > Mg > Fe > Mn > B > Zn > Cu.
The chrysanthemum cultivated in pot is one of the best seller floristic products in the Brazilian floriculture, having high colors diversity, forms and sizes of inflorescences, besides present high post-harvest durability. Therefore, it is necessary to attend the plant nutrition requirement for enabling to express its ornamental potential. The objectives of this research were to evaluate the plant growth and to characterize the nutrients uptake curve of chrysanthemum, cv. ,,Fine Time\", cultivated on pot. The experiment was carried out at greenhouse of the Floriculture Section, Polytechnic College, Federal University of ,,Santa Maria\" (UFSM), Santa Maria, ,,Rio Grande do Sul\" state, Brazil, from September to December 2012. The statistical design was complete randomized with eight treatments and six replications. The plants were sampled and analyzed in intervals of 7 to 14 days according to the plant development stage. The evaluated growth parameters were: length of stems, leaves and roots; number of leaves, roots, sproutings, buds and inflorescences; width and area of leaves; dry matter of leaves, roots, buds, inflorescences, stems and plants. In relation to the nutrients content, accumulation and uptake curve, the N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn on the roots, leaves, stems, buds and inflorescences were evaluated. The parameters stem and root length, number of leaves and roots, dry matter of plant, stems and roots were crescent as function of time, presenting a tendency of stability at end of the crop cycle. The parameters length and width of leaves decrease as function of cultivation time. The decrescente order of organ dry matter accumulation was: leaves > stems > roots > inflorescences > buds. The needs of N, P, S and Cu are equal during the vegetative phase and flowering. The needs of K, Mn and Zn in the plants are higher on the flowering phase. The plant demand of Ca, B, Fe and Mg is higher on the vegetative phase. The needs of macronutrients during vegetative phase and flowering obey, respectively, the following order: Ca > Mg > N > S > P > K and K > P > S > N > Mg > Ca. The needs of micronutrients during vegetative phase and flowering obey, respectively, the following decrescent order: B > Fe> Cu > Zn > Mn and Mn > Zn > Cu > Fe > B. The decrescent sequence of nutrient accumulation on the chrysanthemum plants as function of time was: N > K > P > Ca > S > Mg > Fe > Mn > B > Zn > Cu.

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46

Vaskonen, Timo. "Dietary combination of mineral nutrients and natural plant sterols : effects on serum lipids and blood pressure in experimental obesity." Helsinki : University of Helsinki, 2002. http://ethesis.helsinki.fi/julkaisut/laa/biola/vk/vaskonen/.

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47

au, j. anderson@murdoch edu, and Jonathan Anderson. "Impacts of Amending Bauxite Residue Sands with Residue Fines for the Establishment of Vegetation on Residue Disposal Areas." Murdoch University, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090831.155453.

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Long term storage of bauxite residue materials requires a capping stratum which will limit erosion while stabilizing slopes, limit deep infiltration of water into storage piles, and be aesthetically acceptable to the surrounding community. A diverse native vegetative community capable of surviving seasonal drought, low plant available water and nutrient constraints has the best potential of satisfying most, if not all of these requirements. Current and past rehabilitation of residue disposal areas (RDAs) using species native to southwest Western Australia has exhibited varying success. Current practices at Alcoa World Alumina Australias (Alcoa) Western Australia refineries have bauxite residue fines (< 150 ìm) stored within impoundments, in which the outer embankments are constructed with bauxite residue sands (> 150 ìm). The residue sands are also used as the growth media in the capping stratum for vegetation establishment on the disposal sites. Despite the inherently hostile properties of residue sand (pH > 10, EC(1:5) > 4 dS m-1, and ESP > 50), reductions in alkalinity (pH), salinity (EC) and sodicity (ESP) are corrected, through freshwater leaching, to a greater extent than is possible with residue fines. Although leaching can reduce the hostile character of residue sand, additions of phosphogypsum are typically added to expedite the removal of Na and alkalinity, and inorganic fertilizers are incorporated to improve the nutrient status of the growth media. However, due to the inconsistencies in vegetation establishment, which are attributed to poor water retention, inherent nutrient deficiencies and rapid loss of nutrients within residue sands (because of high hydraulic conductivity), further amendments are required. The aim of this study was to determine if amending the residue sand capping layer with residue fines would enhance its overall growth potential for vegetation establishment. Additions of fines to residue sands were predicted to increase water retention, add nutrients and increase the ability of the growth media to retain nutrients. Comparisons were made between the treated residue fines (seawater washed, carbonated, or unaltered) at a series of fines additions (1 - 20 % w/w) and a control(residue sand) amended with 2% (w/w) phosphogypsum and inorganic fertilizer. Comparisons were to determine the differences in 1) water retention, 2) nutrient concentrations and nutrient retention, and 3) plant growth responses and plant biomass nutrient concentrations between the growth media treatments. Four experiments were set up to measure differences in these variables which included: a glasshouse study involving the growth of Acacia saligna; a germination and emergence study (A.saligna); a two year field study in Western Australia; and a glasshouse column leaching study. Water retention increased with increasing percentage of residue fines addition. Plant available water (PAW) increased up to 110 %, with a 20 % increase in fines, representing an increase of 0.026 m3 PAW m-3 residue growth media, when compared to the residue sand only. This increase in PAW was attributed to changes in pore space distributions, due to the increasing fines contents altering the sandy texture to loamy sand texture class. However, initially much of this increase in PAW may not be realized, due to estimated temporary increases in osmotic potential associated with the high salt contents of residue sand and fines. Fines materials have much greater salt contents, and thus need to be leached to a greater extent than sands to remove the associated osmotic potential effects. Essential plant nutrients (P, K, S, Ca, Mg, and B) were increased with additions of residue fines in the glasshouse studies, although many nutrients (Mg, Zn, Mn and B) were still marginal for sustainable plant growth and development. Seawater treated residue fines additions produced the greatest increases in growth media nutrients with substantial increases in soluble (> 7 mg L-1) and exchangeable (> 0.10 cmolc kg-1) Mg, being up to 400 % greater than all other treatments. Along with these necessary nutrients, concentrations of Na were also increased in all fines additions treatments. Added Na may offset the benefits of fines additions, at least in the short term, due to inhibitions of cation uptake from Na competition. However, in the column leaching study soluble and exchangeable Na was lost rapidly from the profile, due to Ca and K displacement of Na from exchange sites during leaching. Soluble Na was removed from the profile to < 5 % of initial concentrations, after only three pore volumes of leaching, and exchangeable Na was removed from charge sites to less than 25 % of the initial concentration. Fines additions did increase concentrations of Mg and K on exchange sites, thus reflecting increased nutrient retention capacity relative to that in residue sand only. Plant growth responses and plant biomass nutrient concentrations were altered with the additions of residue fines to residue sands. The germination and emergence study demonstrated that the emergence of native seedlings was affected by additions of fines, due to the increased salinity and sodicity of the materials. Acacia saligna seedling emergence was inhibited by EC(1:5) > 2 dS m-1, which was highly correlated with a Na/Ca ratio of > 40, for all treatments, except the seawater fines additions. Seeds sown in seawater treatments emerged from growth media with EC(1:5) as high as 3.33 dS m-1 and appeared to be better correlated with Ca/Mg ratios than any other variable. Native vegetation growth responses showed mixed results in fines treated residues in the field. In the greenhouse study, plant growth tended to decrease with fines additions. Poor plant growth with increasing fines additions occurred despite the increased water retention and increased nutrients. This was attributed to the addition of Na associated with the residue fines, as increases in Na, EC and ESP in fines treatments all appear to have limited growth of Acacia saligna in the glasshouse over three months. Seawater fines additions had elevated Mg and B concentrations in plant biomass, and performed better than the carbonated or unaltered fines treatments, but still had reduced growth compared to the residue sand, which contained lower Na concentrations. Additional plant growth limitations may have occurred, due to possible plant nutrient deficiencies including: Mg, Zn, Mn and B and Na toxicity. Incorporation of residue fines into residue sands did increase water retention, nutrient concentrations and the nutrient retention capacity, but did not enhance the overall growth potential for vegetation, at least in the short term. Reductions in germination and emergence of seedlings and reduced plant growth were attributed to increases in Na concentrations introduced from the fines. Seawater washed residue fines had lower ESP and greater concentrations of nutrients, thus reducing the negative impacts from the additional Na introduced, and showed the greatest promise as a fines amendment. As leaching occurs over the first few initial months of rehabilitation, it is expected that the majority of the Na will be removed, from a system with an addition of 5 to 10 % fines, and the positive benefits of the fines additions will than be realized. Findings also illustrate that delaying the planting of vegetation on RDAs, until adequate leaching has occurred to reduce the Na concentrations, will substantially increase vegetation emergence and establishment.

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48

Mfeka, Nonkululeko. "Morphology and mineral content of cowpea lines in response to planting date and zinc application rate." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2672.

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Thesis (MTech (Agriculture))--Cape Peninsula University of Technology, 2017.
Cowpea (Vigna unguiculata (L.) Walp) is an important grain and fodder legume grown around the world. It is a dual purpose grain legume crop, providing food for man and livestock. Cowpea is identified as a potential crop to diversify food production, minimize production input by improving soil fertility and improve micronutrients of seed, therefore, improving human nutrition. There is limited information available on cowpea production and suitable agronomic practices including planting date to best suit different environmental conditions in South Africa. The objective of this study was therefore to i) evaluate two soil types (sandy and clay soil) and its effect on cowpea, yield components and mineral composition, ii) the effect of different planting date and iii) assess the effect of zinc fertilizer application rate on vegetative, reproductive parameters and mineral content of cowpea seed. A field trial was conducted in Agricultural Research Council (ARC), in two locations Nietvoorbij (clay loam soil) and Bien Donne’ (sandy soil) during the 2015 summer planting season. The trial layout was conducted in a randomised complete block design (RCBD) with five replicates. The factors of the study include three cowpea lines: Cowpea Veg1, M217 and Qukawa with zinc application rate of (0, 15 and 30 kg/ha) through soil application and two planting date (2 October and 2 November 2015). The following agronomic variables were collected, in both locations: germination rate, number of leaves, number of branches, plant height, number of seed per pod, number of pods per plant, pod length, pods per treatment, pod weight, 100 seed weight, morphological traits, moisture content and seed mineral content. Vegetative data was collected on a fourth-night basis on six middle plants per treatment and reproductive parameters were taken after harvest. The variables were subjected to ANOVA using software SAS (2012). Treatments were tested at 5% level of significance and differences between treatments were separated using LSD and DMRT of the SAS 2012 test. The results indicated that vegetative and reproductive parameters measured varied significantly among cowpea lines in each location and across locations due to different cowpea lines and soil type. Line Cowpea Veg1 and Qukawa were the best performing line in both vegetative and yield parameters across the two planting dates in 2015. These lines significantly obtained higher plant height than line M217. Yield and yield parameters were significantly affected by cowpea line. Qukawa obtained the highest seed yield at Bien Donne’ with a mean of 1184.2 kg/ha and seed yield of 686.25 kg/ha for Cowpea Veg1 at Nietvoorbij. The second planting date (2 November 2015) improved germination of plants across the two locations, therefore improving vegetative growth. Zinc (Zn) fertilizer significantly improved plant height across all treatments. An inconsistent response to yield parameters due to Zn application rate was observed. However, though not significant, Zn application of 15 kg/ha increased most of the measured parameters. It was concluded that line Cowpea Veg1 and Qukawa were the best performing lines. The second planting date (2 November) increase germination rate for both locations. It is therefore, recommended that future research should evaluate Zn fertilizer time of application.

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49

Collins, Shane. "Residue composition influences nutrient release from crop residues." University of Western Australia. School of Earth and Geographical Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0171.

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[Truncated abstract] A greater adoption of stubble retention, minimum-till and no-till farming practices for the purposes of conserving soil, water and fertility requires a greater understanding of the complexity of physical and chemical interactions between the soil and crop residues. There is currently insufficient knowledge to allow reliable predictions of the effects of different residue types in different environments on soil fertility and crop growth, owing to the many residue characteristics and environmental interactions that have been shown to affect decomposition or nutrient release. The role of fibre and nutrient composition in nutrient release from crop residues, and implications for residue management techniques, were studied. Canola, lupin and field pea residues, obtained from farmland in Meckering and Northam, Western Australia, were separated into upper and basal stems, leaves, and siliques or pods. This was done to provide materials with a wide range of chemical and physical characteristics, and also allowed consideration of differential residue management of plant organs, such as comparing harvested canola siliques and retained canola stubble. Pre-treatment by chopping and/or humidification was applied to residues to provide some information about the processes of nutrient release. Residues were subjected to simulated rainfall to assess nutrient leaching from plant material, and placed on soil in pots in constant-temperature glasshouse conditions to assess decomposition. Amounts and rates of change of residue fibre and nutrients were determined throughout leaching and decomposition. Energy Dispersive X-ray (EDX) microanalysis was used to assess the location of diffusible ions in air-dried residues and the effects of humidification on nutrient positioning and release. ... However, the release of calcium and magnesium depended on the decomposition of the more recalcitrant components such as cellulose and lignin, as supported by microscopy results showing changes in nutrient distribution following humidification. The proportionality of amounts of calcium and magnesium leached and released during decomposition is likely to suggest a similarity of chemical form more than similarity of function or position of the two elements. Management of crop residues for maximising and optimising the timing of release of different nutrients will need to take into account the placement of different plant types and parts, particle sizes distribution and pre-treatment of material to efficiently manage short- and long-term soil fertility to sustain crops, particularly on degraded soils. Significant nutrient release of potassium, sulphur and magnesium from crop residues can be achieved from surface placement, with the release of potassium and sulphur managed by modifying residue particle size through appropriate harvesting, ploughing or sowing implement selection. High nutrient uptake crops and plant parts where they can be economically viable to grow or separated by the harvesting technique are particularly valuable as sources of nutrients and soil organic matter.

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50

Haider, Muhammad Zulqurnain. "Analysis of molecular mechanisms involved in exchange of nutrients between the fungus and the host plant within the ectomycorrhizal symbiosis." Thesis, Montpellier, SupAgro, 2011. http://www.theses.fr/2011NSAM0042.

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Abstract:

La symbiose mycorhizienne entre les champignons du sol et les racines de la plupart des plantes constitue une relation à bénéfice réciproque et joue un rôle majeur dans la productivité des écosystèmes. Les récentes avancées dans le domaine ont abouties à l'identification et à la caractérisation fonctionnelle de nombreux systèmes de transport du partenaire fongique. Le travail présenté s'inscrit dans le cadre de développement d'outils permettant la localisation de gènes d'intérêts du champignon ectomycorhizien Hebeloma cylindrosporum et de leur caractérisation fonctionnelle. Les systèmes de transport candidats ont été identifiés au sein d'une banque EST du champignon et semblent impliqués dans les échanges de phosphate (Pi) et de potassium (K+) entre Hebeloma et la plante hôte Pinus pinaster. Une stratégie de fusion transcriptionnelle utilisant l'EGFP comme gène rapporteur a été développée pour permettre la localisation de deux transporteurs de phosphate, HcPT1 et HcPT2, d'un transporteur de potassium, HcTrk1, et d'un canal potassique de type Shaker, HcSKC1, dans les hyphes en culture pure et au sein de l'ectomycorhize. Les Agrotransformations de la souche h7 d'Hebeloma avec des vecteurs de fusion transcriptionnelle ont montré une expression mycélienne de l'EGFP sous contrôle des promoteurs de nos gènes d'intérêts. Sous contrôle des différents promoteurs, l'expression de l'EGFP apparait comme étant site-spécifique dans les hyphes différenciés des ectomycorhizes. Le promoteur du transporteur de Pi HcPT1 induit l'expression du gène rapporteur au niveau des hyphes extramatriciels et du manteau mycélien entourant la racine. De plus, son expression est stimulée en cas de carence en Pi, indiquant ainsi l'implication de ce transporteur dans la récupération du Pi du sol lorsque celui-ci devient limitant. Pour ce qui est du promoteur de HcTrk1, il permet l'expression de l'EGFP dans les hyphes extraracinaires et dans le manteau, tandis que celui de HcSKC1 permet son expression au niveau du réseau de Hartig et du manteau. Ceci indique, qu'ils semblent respectivement participer à la récupération du K+ du sol et à son excrétion vers la plante. Pour poursuivre la caractérisation fonctionnelle de nos systèmes de transport candidats, un second canal potassique, HcSKC2, a été isolé à partir de la souche h1 et exprimé dans des ovocytes de xénope. Tout comme HcSKC1, HcSKC2 n'a pas été actif en système d'expression hétérologue. Cependant, des fusions traductionnelles avec l'EGFP ont montré que la protéine HcSKC2 est bien dirigée à la membrane. En perspective, la caractérisation fonctionnelle de ce canal issue de la souche h7 récemment séquencée sera tentée
The mycorrhizal symbiosis made it possible the first plants to conquest emerged lands and is a major biological phenomenon of terrestrial ecosystems. The fungal partner efficiently takes up nutritive ions from the soil solution and transfers them to the host plants in exchange for photosynthetates. However, despite the importance of this symbiosis on ecosystem productivity, our knowledge about molecular processes controlling this symbiotic interaction and solute transports at the membrane level is very scarce. The objective of the project aims at dissecting part of the molecular mechanisms required for a functional ectomycorrhizal symbiosis associated with most of the woody species from boreal and temperate forests, by focusing on K+ exchanges occurring through the continuum soil-hyphae-plant. The general aim of the project is to gain new insights into the molecular mechanisms responsible for the polarization and differentiation of the plasma membrane between the site of nutrient uptake and the site of efflux into the apoplastic space in the ectomycorrhizal root. The team "Canaux Ioniques – Ion channels" has obtained an EST library of the fungus Hebeloma cylindrosporum (1) and has identified and characterized a potassium transporter of the Trk family (2). Also a Shaker-type potassium cannel was identified within the EST library but it is not yet functionally characterized. A second transcript was found from this channel with a longer N-terminus compared to the first transcript isolated in the beginning. Also, a sugar transporter was identified among the ESTs that could participate in the absorption of sugars, coming from the host plant, by the fungus. The objective of the PhD thesis is the functional characterization of these fungal transport systems as well as their localization. The functional characterization of these candidate genes will be accomplished using heterologous expression systems (Xenopus oocytes, COS cells, complementation of yeast mutants) and by the means of electrophysiology. Localization of genes within the fungus being in symbiotic interaction with the host plant, the tree Pinus pinaster, will help to better understand the role of the transport systems. The differentiation of the fungus, when establishing symbiosis, into the specialized interfaces soil-fungus and fungal cell- host plant cell within the ectomycorrhiza (Hartig net) is probably accompanied by a specific expression of transport proteins and ion channels

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Dissertations / Theses on the topic 'Plant nutrients'

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