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Artykuły w czasopismach na temat "Plant nutrients"
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Mattson, Neil S., i Marc W. van Iersel. "Application of the “4R” Nutrient Stewardship Concept to Horticultural Crops: Applying Nutrients at the “Right Time”". HortTechnology 21, nr 6 (grudzień 2011): 667–73. http://dx.doi.org/10.21273/horttech.21.6.667.
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The 4R nutrient stewardship framework presents four concepts to consider when applying fertilizers in a responsible matter; the “right source” of nutrients should be applied at the “right rate” during the “right time” and supplied to the “right place” to ensure their uptake. In this article, we provide ideas to consider when attempting to provide nutrients at the right time. When nutrients are applied at a time when they are not required by the plant, the result can be economic and environmental losses. Oversupply relative to plant demand can result in losses of applied nutrients because of leaching or volatilization. Undersupply relative to demand, especially in the case of phloem-immobile nutrients, may limit plant growth and yield. Several factors interact to affect plant nutrient demand such as growth stage, life history (annual vs. perennial), environmental conditions, and plant health. Techniques such as soil and tissue testing, isotopic labeling, and spectral reflectance have been used with varying degrees of success and expense to measure plant nutrient demand and guide fertilizer decisions. Besides knowledge of plant nutrient demand, efficient nutrient supply also depends on systems that allow precise spatial and temporal delivery of nutrients. Future improvements to the timing of nutrient delivery will depend on improvement in knowledge of plant nutrient demands. For example, targeted gene expression chips show promise for use in rapidly assessing plant status for a broad suite of nutrients. Future developments that allow more precise nutrient delivery or more robust agroecosystems that scavenge available nutrients before they are lost to the environment will also help producers use nutrients more efficiently.
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Ardianti, Arini Ayu, Faris Nur Fauzi Athallah, Restu Wulansari i Kurniawan Sigit Wicaksono. "The relationship Between Soil Chemical Properties and Uptake of Tea Plant Nutrient in PTPN VI Jambi". Jurnal Tanah dan Sumberdaya Lahan 9, nr 1 (1.01.2022): 181–91. http://dx.doi.org/10.21776/ub.jtsl.2022.009.1.20.
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Healthy soil could support plant growth by optimizing the availability of nutrients. The availability of nutrients influences the health of tea plants. Nutrient deficiencies would affect the plant physiology that exhibits the plant withering. This study aimed to define the relationship between soil nutrient availability with plant nutrient uptake. This research was conducted by managing secondary data soil chemical properties, and tea plant nutrients analyzed statistically with Pearson correlation. This study only found a significant correlation between soil pH with P and Mg uptake. Correlation results between soil nutrient and plant nutrient uptake obtained a significantly negative correlation on soil pH with P and Mg nutrients with a correlation value of pH-P (r=-0.52), pH-Mg (r=-0.52). There was no correlation between other soil nutrients and plant nutrient uptake. The results of this study can be used to determine the dose of fertilization and the management recommendation of tea plants.
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Granstedt, Artur. "The potential for Swedish farms to eliminate the use of artificial fertilizers". American Journal of Alternative Agriculture 6, nr 3 (wrzesień 1991): 122–31. http://dx.doi.org/10.1017/s0889189300004070.
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AbstractThis paper discusses data on plant-nutrient conservation in Sweden between 1950 and 1980 and on plant-nutrient balances in conventional and alternative farming. The amounts of plant nutrients supplied in the form of artificial fertilizer in Sweden increased severalfold between 1950 and 1980. The amounts of N and P applied were four times higher than those recovered in agricultural products. This difference not only represents a loss to farmers but also a burden on the environment. This problem is a consequence of the increased separation of crop management from animal husbandry in Sweden. The flow of plant nutrients through the agroecosystem can be represented as follows: Artificial Fertilizers- > Crop Production-> Animal Husbandry- > Losses (air, water, or immobilization).This paper suggests that all farms in Sweden can operate effectively without relying on applications of highly soluble plant nutrients. By recirculating plant nutrients in manure and cultivating nitrogen-fixing species, the need for artificial fertilizers can be eliminated while minimizing nutrient losses and their associated adverse effects on the environment. Successful alternative farms provide practical examples of how a farming system can eliminate its dependence on applications of highly soluble plant nutrients by stressing effective nutrient economy and biological activity. The strategies they use include: matching animal management practices to the farm's own production of feed, thereby reducing net removal of plant nutrients per unit area (in Sweden 0.6–0.8 animal units per ha); minimizing nutrient losses through careful manure management and by using cover crops; and supplying N by nitrogen-fixing ley species, and P and K by soil weathering and by applying supplementary soil improvement materials.
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Anderson, Wendy B., i William G. Eickmeier. "Nutrient resorption in Claytonia virginica L.: implications for deciduous forest nutrient cycling". Canadian Journal of Botany 78, nr 6 (1.06.2000): 832–39. http://dx.doi.org/10.1139/b00-056.
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According to the vernal dam hypothesis, spring ephemeral herbs temporarily sequester large nutrient pools in deciduous forests prior to canopy closure and return the nutrients to the soil following senescence of aboveground tissues. However, many species resorb nutrients from their leaves back to belowground tissues during senescence, and the degree of resorption is often associated with soil nutrient availability. Species that store large proportions of their absorbed nutrients between years are not participating in the temporary sequestering and rapid recycling of nutrients implied by the vernal dam. We investigated the extent to which Claytonia virginica L. sequestered and returned nutrients to the soil in response to nitrogen (N) and phosphorus (P) availability. We tested the effect of nutrient availability on nutrient use efficiency, resorption efficiency, and resorption proficiency (% nutrient in senescent leaves) of Claytonia. Nutrient additions significantly decreased N but not P use efficiency of Claytonia, particularly as the growing season progressed. Nutrient additions also significantly reduced N resorption efficiency from 80 to 47% and decreased P resorption efficiency from 86 to 56%. N and P resorption proficiencies were also significantly lower in senesced leaves of fertilized plants: N concentrations were 2.33% when unfertilized and 4.13% when fertilized, while P concentrations were 0.43% when unfertilized versus 0.57% when fertilized. When unfertilized, Claytonia was more efficient at resorption compared with other spring herbs, but similar to other species when fertilized. However, Claytonia was much less proficient in resorbing nutrients than other reported plants, because senescent tissues maintained substantially higher concentrations of N and P, particularly when fertilized. In conclusion, Claytonia, an important spring ephemeral species, exhibits physiological responses that emphasize its role in the vernal dam by its temporary sequestration and substantial, rapid return of nutrients in deciduous forests. Adding nutrients to the site increases the total mass and the relative proportion of nutrients that Claytonia returns to the soil rather than sequestering between seasons, which ultimately increases nutrient recycling rates within the entire system.Key words: Claytonia virginica, nutrient response, resorption efficiency, nutrient cycling, spring ephemerals, vernal dam.
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Havlin, John, i Ron Heiniger. "Soil Fertility Management for Better Crop Production". Agronomy 10, nr 9 (8.09.2020): 1349. http://dx.doi.org/10.3390/agronomy10091349.
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Increasing crop productivity per unit of land area to meet future food and fiber demand increases both soil nutrient removal and the importance of replenishing soil fertility through efficient nutrient management practices. Significant progress in enhancing nutrient-use efficiency in production agriculture requires improved estimates of plant-available nutrients in the root zone, enhanced crop response to applied nutrients, and reduced offsite nutrient transport. This special issue, Soil Fertility Management for Better Crop Production, presents 15 manuscripts that advance our knowledge of interrelated soil, plant, and management factors important to increasing the nutrient availability and crop recovery of applied nutrients.
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Sivard, Å., T. Ericsson i B. Larsson. "Strategy for nutrient control in modern effluent treatment plants". Water Science and Technology 55, nr 6 (1.03.2007): 157–63. http://dx.doi.org/10.2166/wst.2007.224.
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The fate of nutrients in the modern effluent treatment plant depends on several factors, for example type of treatment plant, availability of nutrients in the specific effluent, dosing of nutrients and sludge age/production. New technologies with the aim to increase the efficiency and stability of the conventional activated sludge process have strongly affected the possibilities to control discharge of nutrients in pulp and paper effluents. A paradox is that a reduction of organic material may often lead to an increase of nutrient discharges. It is of the utmost importance that the operators have good knowledge of the factors affecting nutrient uptake and release in order to minimise nutrient discharge and obtain optimal plant performance. Dosing of nitrogen and phosphorus is one key factor in the sensitive balance in most pulp and paper effluent treatment plants. Correct dosing is crucial as high or low doses might lead not only to increased discharge of nutrients but also to severe operational problems with poor sludge quality, which in turn affects the plant performance for longer periods.
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Roberts, Roland K. "Plant Nutrient Demand Functions for Tennessee with Prices of Jointly Applied Nutrients". Journal of Agricultural and Applied Economics 18, nr 2 (grudzień 1986): 107–12. http://dx.doi.org/10.1017/s0081305200006154.
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AbstractSeveral studies have estimated plant nutrient demand functions for nitrogen, phosphate, and potash. All included own-price effects but excluded prices of jointly applied nutrients. In this study, nutrient demand functions, which include prices of all three nutrients, are estimated for Tennessee by seemingly unrelated regression. Results suggest that cross-price eflfects are important in determining plant nutrient demand, at least in the case of Tennessee, and that multicollinearity need not be a hindrance in all cases to including cross-price eflfects in plant nutrient demand models.
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Asghari, Hamid Reza, i Timothy Richard Cavagnaro. "Arbuscular mycorrhizas enhance plant interception of leached nutrients". Functional Plant Biology 38, nr 3 (2011): 219. http://dx.doi.org/10.1071/fp10180.
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Arbuscular mycorrhizal fungi (AMF) can increase plant growth and nutrition. However, their capacity to reduce the leaching of nutrients through the soil profile is less well understood. Here we present results of an experiment in which the effects of forming arbuscular mycorrhizas (AM) on plant growth and nutrition, nutrient depletion from soil, and nutrient leaching, were investigated in microcosms containing the grass Phalaris aquatica L. Mycorrhizal and non-mycorrhizal plants were grown in a mixture of riparian soil and sand under glasshouse conditions. The formation of AM by P. aquatica significantly increased plant growth and nutrient uptake. Lower levels of NO3–, NH4+ and plant available P in both soil and leachate were observed in columns containing mycorrhizal root systems. These differences in nutrient interception were proportionally greater than the increase in root biomass of the mycorrhizal plants, compared with their non-mycorrhizal counterparts. Taken together, these data indicate that mycorrhizal root systems have an important, but previously little considered, role to play reducing the net loss of nutrients via leaching.
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Limwikran, Tanawan, Irb Kheoruenromne, Anchalee Suddhiprakarn, Nattaporn Prakongkep i Robert J. Gilkes. "Most Plant Nutrient Elements Are Retained by Biochar in Soil". Soil Systems 3, nr 4 (18.11.2019): 75. http://dx.doi.org/10.3390/soilsystems3040075.
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Biochar may contain substantial amounts of plant nutrient elements, and at typical rates of application, may supply luxury levels of K, Ca, P, and other plant nutrients. However, little is known of the agronomic effectiveness of these nutrients because they exist in diverse compounds and are located in the microporous matrix of biochar particles. We have identified the compounds and location of nutrient elements in three biochars and observed their release from biochar particles in soil. Much K was quickly released from biochar but little or no Ca, Mg, S, and P were released over eight months, which represents a very different behavior from chemical fertilizers that are mostly water soluble. There is clearly a need to determine the availability to plant nutrients in biochar. Appropriate laboratory methods should be developed for measuring the availability of plant nutrients as standard methods of fertilizer analysis are ineffective.
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Wright, Robert D. "The Pour-through Nutrient Extraction Procedure". HortScience 21, nr 2 (kwiecień 1986): 227–29. http://dx.doi.org/10.21273/hortsci.21.2.227.
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Abstract Nutrient absorption and subsequent plant growth is related to an adequate supply of the nutrient in the soil solution. Thus, fertilizer practices in a nursery and greenhouse should attempt to maintain nutrient levels in the soil solution that promote optimal growth (2, 3). Maintenance of nutrients for greenhouse and nursery crops is usually via slow-release fertilizer or frequent additions through the irrigation water, where mass flow rather than diffusion is probably the predominant process by which nutrients move to plant root surfaces. In effect, the container medium serves primarily as mechanical support for the plant, and, in contrast to mineral soil systems, nutrients adsorbed to the medium are insignificant in relation to the rate of nutrient uptake and subsequent plant growth. This is particularly true for macronutrients, although the extent that it applies to micronutrients is still not clear.
Rozprawy doktorskie na temat "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 TecnolÃgicoRose 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 à uma cultura de grande valor no mercado interno e externo, devido a esse fato, as rosas geram benefÃcios para o estado do CearÃ. à uma cultura muito exigente em relaÃÃo à 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, à 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 à 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 à 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 serà recomendado aplicar fertilizantes. O sistema estimou que o solo à capaz de suprir a demanda das plantas para P e Fe para todas as cultivares, no entanto, à necessÃrio que haja complementaÃÃo de adubaÃÃo nitrogenada, potÃssica. Assim como para os micronutrientes, o sistema estimou que hà 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, 2017Transpiration 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.
Pełny tekst źródłaKsiążki na temat "Plant nutrients"
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Naeem, M., Abid A. Ansari i Sarvajeet Singh Gill, red. Essential Plant Nutrients. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-58841-4.
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Maathuis, Frans J. M., red. Plant Mineral Nutrients. Totowa, NJ: Humana Press, 2013. http://dx.doi.org/10.1007/978-1-62703-152-3.
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Day, A. D. Plant nutrients in desert environments. Berlin: Springer-Verlag, 1992.
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Miransari, Mohammad. Soil nutrients. Hauppauge, N.Y: Nova Science Publishers, 2011.
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Day, Arden D., i Kenneth L. Ludeke. Plant Nutrients in Desert Environments. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-77652-6.
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Hasanuzzaman, Mirza, Masayuki Fujita, Hirosuke Oku, Kamrun Nahar i Barbara Hawrylak-Nowak, red. Plant Nutrients and Abiotic Stress Tolerance. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-9044-8.
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El-Ramady, Hassan. Glossary of Nutrients: Plant Essential Macro- and Micro-nutrients and Their Deficiency Symptoms. Saarbrücken: VDM Verlag Dr. Müller, 2010.
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McCaskill, Jim. Plant nutrient facts for hydroponics & how to make your own fully formulated plant nutrient. N. Hollywood, CA (10705 Burbank Blvd. N. Hollywood 91601): Foothill Hydroponics, 1998.
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Koerkle, Edward H. Surface-water quality changes after 5 years of nutrient management in the Little Conestoga Creek headwaters, Pennsylvania, 1989-91. Lemoyne, Pa: U.S. Geological Survey, 1997.
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Koerkle, Edward H. Surface-water quality changes after 5 years of nutrient management in the Little Conestoga Creek headwaters, Pennsylvania, 1989-91. Lemoyne, Pa: U.S. Geological Survey, 1997.
Znajdź pełny tekst źródłaCzęści książek na temat "Plant nutrients"
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Blake, George R., Gary C. Steinhardt, X. Pontevedra Pombal, J. C. Nóvoa Muñoz, A. Martínez Cortizas, R. W. Arnold, Randall J. Schaetzl i in. "Plant Nutrients". W Encyclopedia of Soil Science, 560–71. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-3995-9_441.
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Mengel, Konrad, Ernest A. Kirkby, Harald Kosegarten i Thomas Appel. "Plant Nutrients". W Principles of Plant Nutrition, 1–13. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-1009-2_1.
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Day, Arden D., i Kenneth L. Ludeke. "Plant Nutrients". W Plant Nutrients in Desert Environments, 3–8. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-77652-6_2.
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Mitra, Sisir. "Plant nutrition and irrigation." W Guava: botany, production and uses, 148–71. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789247022.0007.
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Abstract This chapter focuses on plant nutrition and irrigation in guava production. Information is given on soil, salinity, nutrient uptake, role of nutrients, fertilizer rate and time of application, foliar application, integrated nutrient management, tissue analysis, organic production, water management, and fertigation.
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Fricke, Wieland. "Plant Single Cell Sampling". W Plant Mineral Nutrients, 209–31. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-62703-152-3_14.
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Danku, John M. C., Brett Lahner, Elena Yakubova i David E. Salt. "Large-Scale Plant Ionomics". W Plant Mineral Nutrients, 255–76. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-62703-152-3_17.
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Podar, Dorina. "Plant Growth and Cultivation". W Plant Mineral Nutrients, 23–45. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-62703-152-3_2.
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Moscatiello, Roberto, Barbara Baldan i Lorella Navazio. "Plant Cell Suspension Cultures". W Plant Mineral Nutrients, 77–93. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-62703-152-3_5.
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Hell, RÜdiger, i Heinz Rennenberg. "The Plant Sulphur Cycle". W Nutrients in Ecosystems, 135–73. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-5100-9_5.
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Maathuis, Frans J. M., i Eugene Diatloff. "Roles and Functions of Plant Mineral Nutrients". W Plant Mineral Nutrients, 1–21. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-62703-152-3_1.
Pełny tekst źródłaStreszczenia konferencji na temat "Plant nutrients"
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Rancane, Sarmite, Aldis Karklins i Dagnija Lazdina. "Circulation of plant nutrients in bioenergy production". W 21st International Scientific Conference Engineering for Rural Development. Latvia University of Life Sciences and Technologies, Faculty of Engineering, 2022. http://dx.doi.org/10.22616/erdev.2022.21.tf107.
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Zaharioiu, Anca Maria, Roxana Elena Ionete, Claudia Sandru, Marius Constantinescu i Oana Romina Botoran. "ALTITUDINAL CHANGES IN TEMPERATE FORESTS FROM CARPATHIAN MOUNTAINS". W 22nd SGEM International Multidisciplinary Scientific GeoConference 2022. STEF92 Technology, 2022. http://dx.doi.org/10.5593/sgem2022/5.1/s20.001.
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This study investigated changes in carbon (C) and nitrogen (N) concentrations in the three components of the forest ecosystem (leaves, bark and soil) along an altitudinal gradient in the temperate forests of Romania. The properties and processes within the forest ecosystem are influenced by altitude. The leaves, litter and soil are important in the good development of the ecosystem and in the cycle of the elements. Plants extract the nutrients necessary for life and growth from the soil in which they carry out their entire activity. With the help of litter, the soil is supplied with nutrients useful for plants. The soil can be influenced by pH, being a physical factor, and in the forests of Romania it decreases with altitude, becoming acidic. In this paper, studies were performed to investigate the chemical components in the soil-water-plant chain, which highlights the importance of stoichiometric variation of nutrients in plant organs and their relationships with other components of the forest ecosystem.
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de Lange, Elvira. "Beating the bugs in the cranberry bogs — nutrients influence plant resistance". W 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.116256.
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Shammout, Maisa'a W., i Hana Zakaria. "Wild water lentils plant (Duckweed,Lemnasp.) in nutrients removal of Jordan's irrigation ponds". W 2013 International Conference on Biomedical Engineering and Environmental Engineering. Southampton, UK: WIT Press, 2014. http://dx.doi.org/10.2495/icbeee130671.
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Nedyalkov, Ivaylo, Todd Guerdat, Drue Seksinsky, Sylvia Romero, Justin Stickney i Ethan Pirie. "Numerical and Experimental Investigation of Flow in Fish Tanks for Small-Scale Aquaponic Systems". W ASME 2017 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/fedsm2017-69395.
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Aquaponic systems combine recirculating aquaculture (growing of fish) with hydroponics (growing of plants in water). The fish in the recirculating aquaculture systems provide nutrients for the plants and the plants remove excess nutrients from the water, making these systems more efficient than traditional farming methods in terms of nutrient utilization. Small, recirculating aquaponic systems may provide a more sustainable and cost-effective alternative for securing food supply in both developing and developed nations. Recirculating aquaculture systems tend to be capital-intensive and require significant power to circulate the water in the fish tanks, which helps with the removal of waste and the distribution of oxygen. To reduce capital costs, alternative, culture vessels made from locally available materials were investigated (i.e. square-shaped tanks, and international bulk containers - IBC). These non-standard shaped culture tanks, pose an additional challenge for proper circulation of the water as compared to traditional round tanks. To address the issue of circulation, numerical and experimental data were obtained for rectangular containers. The numerical results were obtained using OpenFoam models of the experimental setup. The experimental data were obtained by measuring flow velocities in an IBC tank using Acoustic Doppler Velocimetry. Currently the experimental data show good repeatability when data are taken for at least five minutes at each position in the tank. The focus of the continuing work is to establish a good agreement between numerical and experimental results. Ultimately the study will contribute to the design of cost-effective recirculating aquaponic fish and plant systems which require lower capital expenditures and achieve energy-efficient circulation of water in the fish culture tanks.
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Alejandra Coloma, John P. Chastain i Kathy P. Moore. "Fractionation of Solids, Plant Nutrients, and Carbon as a Result of Screening Broiler Litter". W 2004, Ottawa, Canada August 1 - 4, 2004. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2004. http://dx.doi.org/10.13031/2013.16792.
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Kerry, R., B. Ingram i M. Oliver. "78. Sampling needs to establish effective management zones for plant nutrients in precision agriculture". W 13th European Conference on Precision Agriculture. The Netherlands: Wageningen Academic Publishers, 2021. http://dx.doi.org/10.3920/978-90-8686-916-9_78.
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Ibáñez Otazua, Nora, María Blázquez Sánchez, Oscar Ruiz Yarritu, Idoia Unzueta Balmaseda, Ahmed Mohamed Aboseif, Nevine M. Abou Shabana, Mostafa Korany S. Taha i Ashraf Mohamed Abdelsamee Goda. "Integrated Multitrophic Aquaponics—A Promising Strategy for Cycling Plant Nutrients and Minimizing Water Consumption". W IECHo 2022. Basel Switzerland: MDPI, 2022. http://dx.doi.org/10.3390/iecho2022-12493.
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Nawaz, Rab, Hathairatana Garivait i Patana Anurakpongsatorn. "Impacts of precipitation on leaching behavior of plant nutrients in agricultural soils of the tropics". W 2010 2nd International Conference on Chemical, Biological and Environmental Engineering (ICBEE). IEEE, 2010. http://dx.doi.org/10.1109/icbee.2010.5651678.
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Zirka, A. Yu, i A. D. Plastun. "STUDYING THE PROSPECTS OF APPLICATION OF MICROGREEN FOR SPECIALIZED NUTRITION". W I International Congress “The Latest Achievements of Medicine, Healthcare, and Health-Saving Technologies”. Kemerovo State University, 2023. http://dx.doi.org/10.21603/-i-ic-43.
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The range and popularity of vegetable raw materials is growing, in connection with this, there is a need to study the prospects for the use of new or less popular food products of the "superfood" category for specialized nutrition as a source of essential macro and micro nutrients. The study analyzed the benefits and possible difficulties of using microgreens for specialized nutrition. Microgreens can be a good source of essential nutrients, since they have a wide range of them in their chemical composition, which can be used to form a complete diet. However, to date, the use of microgreens is associated with difficulties, since this category of raw materials of plant origin has been little studied.
Raporty organizacyjne na temat "Plant nutrients"
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Harman, Gary E., i Ilan Chet. Enhancing Crop Yield through Colonization of the Rhizosphere with Beneficial Microbes. United States Department of Agriculture, grudzień 2001. http://dx.doi.org/10.32747/2001.7580684.bard.
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At the start of this project, fungi in the genus Trichoderma were known to be potent biocontrol agents, and their primary mechanism was considered to via direct effects upon the target fungi. Due in large part to the efforts of the two PIs, we now know that this view is far too limited; while Trichoderma spp. do indeed have direct effects on pathogenic fungi, they have very far reaching effects directly upon plants. Indeed, these fungi must be considered as opportunistic plant symbionts; they provide a number of benefits to plants and themselves are favored by large numbers of healthy roots. Research under this BARD grant has demonstrated that These fungi induce resistance mechanisms in plants. They increase root development and depth of rooting; Bradyrhizobium enhances this effect in soybean. They enhance uptake of plant nutrients. They have abilities to solubilize nutrients, such as oxidized metals and insoluble phosphorus compounds by a variety of different mechanisms and biochemicals. This is a marked expansion of our knowledge of the abilities of these organisms. This knowledge has direct implications for understanding of basic plant responses and abilities, and already is being used to improve plant productivity and reduce pollution of the environment.
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Barefield, James, Elizabeth Judge, Samuel Clegg, John Berg, James Colgan, David Kilcrease, Heather Johns i in. Laser-Induced Breakdown Spectroscopy (LIBS): Applications to Analysis Problems from Nuclear Material to Plant Nutrients for Sustainable Agriculture. Office of Scientific and Technical Information (OSTI), listopad 2014. http://dx.doi.org/10.2172/1164426.
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Lers, Amnon, i Pamela J. Green. Analysis of Small RNAs Associated with Plant Senescence. United States Department of Agriculture, marzec 2013. http://dx.doi.org/10.32747/2013.7593393.bard.
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Senescence is an agriculturally significant process due to its negative impact to crop yield and postharvest quality. The genetic regulatory systems controlling senescence induction and progress respond to both developmental and environmental stress signals and involve numerous gene expression changes. Knowledge about the key molecular factors which control senescence is very limited. MicroRNAs (miRNAs) are a class of small RNAs which typically function by guiding cleavage of target messenger RNAs. They have been shown to play major roles in a variety of plant processes including development, responses to environmental stresses, and senescence. The long-term goal of this work is to elucidate roles of small RNAs associated with plant senescence. The hypothesis underlying this research is that miRNA-mediated regulation makes important contributions to the senescence process in plants. Specific, original research objectives included: 1) Profiling of small RNAs from senescing plants; 2) Data Analysis and public access via a user-friendly web interface; 3) Validation of senescence-associated miRNAs and target RNAs; 4) Development of transgenic plants for functional analysis of miRNAs in Arabidopsis. Major revisions made in the research compared to the original work plan included 1) Exclusion of the planned work with tomato as recommended by the BARD review panel; 2) Performing miRNA study also in senescing Arabidopsis siliques, in addition to senescing leaves. To identify senescenceregulation of miRNAs in Arabidopsis thaliana, eight small RNA libraries were constructed and sequenced at four different stages of development and senescence from both leaves and siliques, resulting in more than 200 million genome-matched sequences. Parallel Analysis of RNA Ends (PARE) libraries, which enable the large-scale examination of miRNA-guided cleavage products, were also constructed and sequenced, resulting in over 750 million genome-matched sequences. These massive datasets lead to the identification of new miRNAs, as well as new regulation of known miRNAs and their target genes during senescence, many of which have established roles in nutrient responsiveness and cell structural integrity. In keeping with remobilization of nutrients thought to occur during senescence, many miRNAs and targets had opposite expression pattern changes between leaf and silique tissues during the progression of senescence. Taken together, these findings highlight the integral role that miRNAs may play in the remobilization of resources and alteration of cellular structure that is known to occur in senescence. Experiments were initiated for functional analysis of specific senescence-associated miRNAs and respective target genes. Transgenic Arabidopsis plants were generated in which miR408, found in this study to be significantly induced in leaf senescence, was over-expressed either constitutively or under a senescence-specific promoter. These plants are currently being characterized for any altered phenotypes. In addition T-DNA knock out mutants for various target genes identified in this research are being analyzed. This work provides insights about specific miRNAs that contribute to leaf and silique senescence. The knowledge generated may suggest new strategies to monitor and alter the progression of senescence in crops for agricultural improvement.
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Palmborg, Cecilia. Fertilization with digestate and digestate products – availability and demonstration experiments within the project Botnia nutrient recycling. Department of Agricultural Research for Northern Sweden, Swedish University of Agricultural Sciences, 2022. http://dx.doi.org/10.54612/a.25rctaeopn.
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To increase our food security in Västerbotten we will need to become more self-sufficient of both energy, feed and nutrients that are now imported to the region. Biogas production from different waste streams is one solution to this. Biogas is produced using biowaste or sewage sludge as substrate in the major cities Umeå and Skellefteå. Biogas systems offer a range of benefits to society. Biogas production is currently prized for its climate benefits when replacing fossil fuels for the production of heat, electricity and vehicle gas, but at Bothnia Nutrient Recycling we have studied how to use the digestate, i.e. the residual product of production, as fertilizer in agriculture. We have been working to improve profitability for biogas producers and develop sustainable products from recycled nutrients, like phosphorus and nitrogen. Improving the uses for digestate increases self-sufficiency in agriculture and contributes to a circular economy. We conducted three agricultural demonstration experiments in collaboration with agricultural high schools in Finland and Sweden to introduce digestate and digestate products to the future farmers in the regions. We found that it may be possible to replace cattle slurry with compost when growing maize despite the low levels of nitrogen, N, available to plants in the compost. In barley, NPK fertilizers gave the highest yield. Digestate from HEMAB and sludge biochar supplemented with recycled ammonium sulphate gave a smaller yield but higher than unfertilized crop. Digestate from a dry digestion biogas plant in Härnösand was better suited to barley than to grass because in an experiment on grass ley the viscous fertilizer did not penetrate the grass and did not increase the growth of the grass. Fertilizer effects on crop quality were small. There was no increased uptake of heavy metals in barley after fertilization with digestate or digestate products compared to NPK fertilization. These demonstration experiments show that more thorough scientific experimentation is needed as a foundation for recommendations to farmers. The amounts of nitrogen and phosphorous in digestate from Västerbotten that could become used as fertilizer were modelled. It showed that if sewage sludge digestate is used to make sludge biochar and ammonium sulphate and the other available digestates are used directly in agriculture, the entire phosphorous demand but only a small part of the nitrogen demand in the county, could be covered. Thus, to achieve a true circular food production, development and increase of both the waste handling sector and agriculture is needed.
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Савосько, Василь Миколайович, Юлія Віліївна Бєлик, Юрій Васильович Лихолат, Герман Хайльмейер i Іван Панасович Григорюк. Macronutrients and Heavy Metals Contents in the Leaves of Trees from the Devastated Lands at Kryvyi Rih District (Central Ukraine). КДПУ, 2020. http://dx.doi.org/10.31812/123456789/4151.
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The relevance of these studies was due to the need to clarify the biogeochemical characteristics of woody plant species that grow naturally on devastated lands. The object of this paper: to carry out a comparative analysis of macro nutrients and heavy metals contents in the leaves of trees spontaneously sprouting on the devastated lands at the Kryvyi Rih District. This research was performed at Petrovsky waste rock dump, the Central part of the Kryvyi Rih iron-ore & metallurgical district (Dnipropetrovsk region, Ukraine). The macronutrients (K, Ca, Mg, P and S) and heavy metals (Fe, Mn, Zn, Cu, Pb and Cd) contents in the leaves of three species of the trees (Ash-leaved Maple Acer negundo L., Silver Birch Betula pendula Roth. and Black Locust Robinia pseudoacacia L.) that were collected on devastated lands were assessed. It was established that trees which grow on the Petrovsky dump take place under evident shortage of nutrients (especially K and P) and excess of metals (especially Fe, Mn and Zn). Taking into account the revealed values of macronutrients optimal concentrations and revealed the heavy metals lowest content in the leaves, we assume that Ash-leaved maple and Black locust (compared to the Silver Birch) are more resistant to the geochemical conditions of devastated lands.
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Granot, David, Richard Amasino i Avner Silber. Mutual effects of hexose phosphorylation enzymes and phosphorous on plant development. United States Department of Agriculture, styczeń 2006. http://dx.doi.org/10.32747/2006.7587223.bard.
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Research objectives 1) Analyze the combined effects of hexose phosphorylation and P level in tomato and Arabidopsis plants 2) Analyze the combined effects of hexose phosphorylation and P level in pho1 and pho2 Arabidopsis mutants 3) Clone and analyze the PHO2 gene 4) Select Arabidopsis mutants resistant to high and low P 5) Analyze the Arabidopsis mutants and clone the corresponding genes 6) Survey wild tomato species for growth characteristics at various P levels Background to the topic Hexose phosphorylating enzymes, the first enzymes of sugar metabolism, regulate key processes in plants such as photosynthesis, growth, senescence and vascular transport. We have previously discovered that hexose phosphorylating enzymes might regulate these processes as a function of phosphorous (P) concentration, and might accelerate acquisition of P, one of the most limiting nutrients in the soil. These discoveries have opened new avenues to gain fundamental knowledge about the relationship between P, sugar phosphorylation and plant development. Since both hexose phosphorylating enzymes and P levels affect plant development, their interaction is of major importance for agriculture. Due to the acceleration of senescence caused by the combined effects of hexose phosphorylation and P concentration, traits affecting P uptake may have been lost in the course of cultivation in which fertilization with relatively high P (30 mg/L) are commonly used. We therefore intended to survey wild tomato species for high P-acquisition at low P soil levels. Genetic resources with high P-acquisition will serve not only to generate a segregating population to map the trait and clone the gene, but will also provide a means to follow the trait in classical breeding programs. This approach could potentially be applicable for other crops as well. Major conclusions, solutions, achievements Our results confirm the mutual effect of hexose phosphorylating enzymes and P level on plant development. Two major aspects of this mutual effect arose. One is related to P toxicity in which HXK seems to play a major role, and the second is related to the effect of HXK on P concentration in the plant. Using tomato plants we demonstrated that high HXK activity increased leaf P concentration, and induced P toxicity when leaf P concentration increases above a certain high level. These results further support our prediction that the desired trait of high-P acquisition might have been lost in the course of cultivation and might exist in wild species. Indeed, in a survey of wild species we identified tomato species that acquired P and performed better at low P (in the irrigation water) compared to the cultivated Lycopersicon esculentum species. The connection between hexose phosphorylation and P toxicity has also been shown with the P sensitive species VerticordiaplumosaL . in which P toxicity is manifested by accelerated senescence (Silber et al., 2003). In a previous work we uncovered the phenomenon of sugar induced cell death (SICD) in yeast cells. Subsequently we showed that SICD is dependent on the rate of hexose phosphorylation as determined by Arabidopsis thaliana hexokinase. In this study we have shown that hexokinase dependent SICD has many characteristics of programmed cell death (PCD) (Granot et al., 2003). High hexokinase activity accelerates senescence (a PCD process) of tomato plants, which is further enhanced by high P. Hence, hexokinase mediated PCD might be a general phenomena. Botrytis cinerea is a non-specific, necrotrophic pathogen that attacks many plant species, including tomato. Senescing leaves are particularly susceptible to B. cinerea infection and delaying leaf senescence might reduce this susceptibility. It has been suggested that B. cinerea’s mode of action may be based on induction of precocious senescence. Using tomato plants developed in the course of the preceding BARD grant (IS 2894-97) and characterized throughout this research (Swartzberg et al., 2006), we have shown that B. cinerea indeed induces senescence and is inhibited by autoregulated production of cytokinin (Swartzberg et al., submitted). To further determine how hexokinase mediates sugar effects we have analyzed tomato plants that express Arabidopsis HXK1 (AtHXK1) grown at different P levels in the irrigation water. We found that Arabidopsis hexokinase mediates sugar signalling in tomato plants independently of hexose phosphate (Kandel-Kfir et al., submitted). To study which hexokinase is involved in sugar sensing we searched and identified two additional HXK genes in tomato plants (Kandel-Kfir et al., 2006). Tomato plants have two different hexose phosphorylating enzymes; hexokinases (HXKs) that can phosphorylate either glucose or fructose, and fructokinases (FRKs) that specifically phosphorylate fructose. To complete the search for genes encoding hexose phosphorylating enzymes we identified a forth fructokinase gene (FRK) (German et al., 2004). The intracellular localization of the four tomato HXK and four FRK enzymes has been determined using GFP fusion analysis in tobacco protoplasts (Kandel-Kfir et al., 2006; Hilla-Weissler et al., 2006). One of the HXK isozymes and one of the FRK isozymes are located within plastids. The other three HXK isozymes are associated with the mitochondria while the other three FRK isozymes are dispersed in the cytosol. We concluded that HXK and FRK are spatially separated in plant cytoplasm and accordingly might play different metabolic and perhaps signalling roles. We have started to analyze the role of the various HXK and FRK genes in plant development. So far we found that LeFRK2 is required for xylem development (German et al., 2003). Irrigation with different P levels had no effect on the phenotype of LeFRK2 antisense plants. In the course of this research we developed a rapid method for the analysis of zygosity in transgenic plants (German et al., 2003).
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Wolf, Shmuel, i William J. Lucas. Involvement of the TMV-MP in the Control of Carbon Metabolism and Partitioning in Transgenic Plants. United States Department of Agriculture, październik 1999. http://dx.doi.org/10.32747/1999.7570560.bard.
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The function of the 30-kilodalton movement protein (MP) of tobacco mosaic virus (TMV) is to facilitate cell-to-cell movement of viral progeny in infected plants. Our earlier findings have indicated that this protein has a direct effect on plasmodesmal function. In addition, these studies demonstrated that constitutive expression of the TMV MP gene (under the control of the CaMV 35S promoter) in transgenic tobacco plants significantly affects carbon metabolism in source leaves and alters the biomass distribution between the various plant organs. The long-term goal of the proposed research was to better understand the factors controlling carbon translocation in plants. The specific objectives were: A) To introduce into tobacco and potato plants a virally-encoded (TMV-MP) gene that affects plasmodesmal functioning and photosynthate partitioning under tissue-specific promoters. B) To introduce into tobacco and potato plants the TMV-MP gene under the control of promoters which are tightly repressed by the Tn10-encoded Tet repressor, to enable the expression of the protein by external application of tetracycline. C) To explore the mechanism by which the TMV-MP interacts with the endogenous control o~ carbon allocation. Data obtained in our previous project together with the results of this current study established that the TMV-MP has pleiotropic effects when expressed in transgenic tobacco plants. In addition to its ability to increase the plasmodesmal size exclusion limit, it alters carbohydrate metabolism in source leaves and dry matter partitioning between the various plant organs, Expression of the TMV-MP in various tissues of transgenic potato plants indicated that sugars and starch levels in source leaves are reduced below those of control plants when the TMV-MP is expressed in green tissue only. However, when the TMV-MP was expressed predominantly in PP and CC, sugar and starch levels were raised above those of control plants. Perhaps the most significant result obtained from experiments performed on transgenic potato plants was the discovery that the influence of the TMV-MP on carbohydrate allocation within source leaves was under developmental control and was exerted only during tuber development. The complexity of the mode by which the TMV-MP exerts its effect on the process of carbohydrate allocation was further demonstrated when transgenic tobacco plants were subjected to environmental stresses such as drought stress and nutrients deficiencies, Collectively, these studies indicated that the influence of the TMV-MP on carbon allocation L the result of protein-protein interaction within the source tissue. Based on these results, together with the findings that plasmodesmata potentiate the cell-to-cell trafficking of viral and endogenous proteins and nucleoproteins complexes, we developed the theme that at the whole plant level, the phloem serves as an information superhighway. Such a long-distance communication system may utilize a new class of signaling molecules (proteins and/or RNA) to co-ordinate photosynthesis and carbon/nitrogen metabolism in source leaves with the complex growth requirements of the plant under the prevailing environmental conditions. The discovery that expression of viral MP in plants can induce precise changes in carbon metabolism and photoassimilate allocation, now provide a conceptual foundation for future studies aimed at elucidating the communication network responsible for integrating photosynthetic productivity with resource allocation at the whole-plant level. Such information will surely provide an understanding of how plants coordinate the essential physiological functions performed by distantly-separated organs. Identification of the proteins involved in mediating and controlling cell-to-cell transport, especially at the companion cell-sieve element boundary, will provide an important first step towards achieving this goal.
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Shtienberg, Dan, William Fry, Amos Dinoor, Thomas Zitter i Uzi Kafkafi. Reduction in Pesticide Use in Plant Disease Control by Integration of Chemical and Non-Chemical Factors. United States Department of Agriculture, maj 1995. http://dx.doi.org/10.32747/1995.7613027.bard.
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The long term goal of this research project was to improve control efficiency of Alternaria diseases while reducing fungicide use, by integration of chemical and non-chemical factors. Non-chemical factors were genotype resistance, age-related resistance and fertilizers. The Specific objectives were: 1) To quantify changes in resistance among genotypes and over time in terms of disease development and specific phases of the disease cycle; 2) To quantify the effects of fertilizers applied to the foliage alone, or in combination with a fungicide, on disease development; 3) To quantify the relative contribution of genotype resistance, age-related resistance and fungicide type to the reduction of disease development; 4) To develop a strategy for integration of chemical and non-chemical factors which will achieve optimal disease suppression. The influence of physiological age of cotton plants and of the individual leaves, on disease incidence and on the rate of lesion expansion of A. macrospora was examined on leaves sampled from the field. Both parameters increased with the physiological age of individual leaves but were not affected by the age of the whole plant. The hypothesis that enrichment of the foliage with nitrogen and potassium may enhance host resistance to Alternaria and thus reduce disease severity, was examined for potato and tomato (A. solani ) and for cotton (A. macrospora ). Under controlled environment conditions, application of urea or KNO3 resulted in some reduction in disease development; however, foliar application of both nutrients (8-10 sprays in total) did not affect Alternaria severity in the field. Systemic fungicides against Alternaria (e.g. , tebuconazole and difenoconazole) are more effective than the commonly used protectant fungicides (e.g. mancozeb and chlorothalonil). Concepts for the integration of genotype resistance, age-related resistances and fungicide for the suppression of Alternaria diseases were developed and evaluated. It was found that reduction in host resistance, with age and among genotypes, can be compensated for by adjusting the intensity of fungicide applications, i.e. by increasing the frequency of sprays and by spraying systemic fungicides towards the end of the season. In, moderately resistant cultivars protection can be achieved by spraying at longer intervals than susceptible cultivars. The concepts for integration were evaluated in field trials for cotton, potatoes and tomatoes. By following these concepts it was possible to save up to five sprays out of 8-10 in a growing season.
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Katan, Jaacov, i Michael E. Stanghellini. Clinical (Major) and Subclinical (Minor) Root-Infecting Pathogens in Plant Growth Substrates, and Integrated Strategies for their Control. United States Department of Agriculture, październik 1993. http://dx.doi.org/10.32747/1993.7568089.bard.
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In intensive agriculture, harmful soilborne biotic agents, cause severe damage. These include both typical soilborne (clinical) major pathogens which destroy plants (e.g. Fusarium and Phytophthora pathogens), and subclinical ("minor") pathogens (e.g. Olpidium and Pythium). The latter cause growth retardation and yield decline. The objectives of this study were: (1) To study the behavior of clinical (major) and subclinical (minor) pathogens in plant growth substrate, with emphasis on zoosporic fungi, such as Pythium, Olipidium and Polymyxa. (2) To study the interaction between subclinical pathogens and plants, and those aspects of Pythium biology which are relevant to these systems. (3) To adopt a holistic-integrated approach for control that includes both eradicative and protective measures, based on a knowledge of the pathogens' biology. Zoospores were demonstrated as the primary, if not the sole propagule, responsible for pathogen spread in a recirculating hydroponic cultural system, as verified with P. aphanidermatum and Phytophthora capsici. P. aphanidermatum, in contrast to Phytophthora capsici, can also spread by hyphae from plant-to-plant. Synthetic surfactants, when added to the recirculating nutrient solutions provided 100% control of root rot of peppers by these fungi without any detrimental effects on plant growth or yield. A bacterium which produced a biosurfactant was proved as efficacious as synthetic surfactants in the control of zoosporic plant pathogens in the recirculating hydroponic cultural system. The biosurfactant was identified as a rhamnolipid. Olpidium and Polymyxa are widespread and were determined as subclinical pathogens since they cause growth retardation but no plant mortality. Pythium can induce both phenomena and is an occasional subclinical pathogen. Physiological and ultrastructural studies of the interaction between Olpidium and melon plants showed that this pathogen is not destructive but affects root hairs, respiration and plant nutrition. The infected roots constitute an amplified sink competing with the shoots and eventually leading to growth retardation. Space solarization, by solar heating of the greenhouse, is effective in the sanitation of the greenhouse from residual inoculum and should be used as a component in disease management, along with other strategies.
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Alvez, Juan, James Cropper, Lynn Knight, Ed Rayburn, Howard Skinner, Kathy Soder i Mike Westendorf. Managing Grazing to Improve Climate Resilience. USDA Northeast Climate Hub, luty 2017. http://dx.doi.org/10.32747/2017.6956540.ch.
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Heavy rain events have increased dramatically in the Northeastern United States. These downpours are causing more soil erosion and nutrient runoff. Increasing summer temperatures may also amplify plant stress and limit productivity.