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Showing 11 to 12 of 12 (0.056 seconds)Spelling suggestions: "subject:"ammonium phosphate"" "subject:"ammmonium phosphate""
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Fertilizantes fosfatados para a cana-de-açúcar aplicados em pré plantio (fosfatagem) / Phosphate fertilizers for sugarcane used in pre-planting (Phosphorus fertilizer application)Sousa, Robson Thiago Xavier de 07 February 2011 (has links)
Phosphate application is still rarely used in sugarcane and can be done with phosphorus
fertilizers of long residual period. This study evaluated the effect of phosphate fertilizers
applied in the whole area before planting on sugarcane yield and technological quality.
The study was done at Jalles Machado sugar-mill, in Goianésia-GO, during three
growing seasons. The treatments consisted of five different phosphorus sources, soluble
and insoluble, applied in the rate equivalent to 300 kg ha-1 P2O5. The fertilizers used
were: triple superphosphate, mono-ammonium phosphate (MAP), Arad phosphate rock,
Itafós phosphate rock and magnesium thermophosphate. The effects of these fertilizers
were evaluated by analysis of plant height (height from ground to TVD), leaf
phosphorus content, sugarcane yield in cane plant, first ratoon and second ratoon, by
technology parameters in ratoon, by sugar produced and by agronomic efficiency.
Application of magnesium thermophosphate and triple superphosphate resulted in
greater plant cane height. Leaf concentrations of phosphorus in cane showed the
superiority of MAP, magnesium thermophosphate and triple superphosphate. Phosphate
applications did not affect yield of cane plant, but increased yield of sugarcane ratoon as
well as the amount of sugar produced per hectare. In general, the residual effect of
insoluble phosphates increased over the years. The Agronomic Efficiency Indices (AEI)
of phosphate decreased in the following order: Triple superphosphate (100%)>
Thermophosphate (89%)> MAP (80%)>Itafós phosphate rock (67%)> Arad phosphate
rock (60 %). / A fosfatagem é ainda uma prática pouco utilizada na cultura da cana-de-açúcar e pode
ser feita com fertilizantes fosfatados de efeito residual longo. Este trabalho teve como
objetivo avaliar o efeito de fertilizantes fosfatados aplicados em área total antes do
plantio da cana-de-açúcar na produção de colmos e qualidade da matéria prima de
cana-de-açúcar. O experimento foi conduzido na Usina Jalles Machado, no município
de Goianésia-GO durante três anos agrícolas. Os tratamentos foram constituídos de
cinco fertilizantes fosfatados, solúveis e insolúveis na dose equivalente a 300 kg ha-1
de P2O5. Os fertilizantes usados foram: superfosfato triplo, monoamônio fosfato
(MAP), fosfato natural reativo de Arad, fosfato natural de Itafós e termofosfato
magnesiano. Para avaliar os efeitos imediatos e residuais destes fertilizantes, foram
utilizados parâmetros tais como: altura de plantas (altura do solo até TVD), teor foliar
de fósforo, produtividade da cana-de-açúcar na cana-planta, soca e ressoca, análise
tecnologia na soqueira, quantidade de açúcar produzido e índice de eficiência
agronômica dos fertilizantes utilizados. Na cana planta a adubação fosfatada
proporcionou maior altura de plantas com a aplicação do termofosfato magnesiano e
do superfosfato triplo. As concentrações de fósforo (P) nas folhas de cana-planta
indicaram superioridade do MAP, termofosfato-magnesiano e superfosfatto-triplo. A
fosfatagem não influenciou a produtividade da cana-planta, porém aumentou a
produtividade da cana soca bem como a quantidade de açúcar produzida por hectare.
De uma forma geral, o efeito residual dos fosfatos insolúveis aumentou no decorrer
dos anos. O Índice de Eficiência Agronômica (IEA) dos fosfatos diminuiu na seguinte
ordem: Superfosfato triplo (100 %) > Termofosfato (89%) > MAP (80%) > Fosfato
Itafós (67%) > Fosfato Arad ( 60%). / Mestre em Agronomia
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| 12 |
Analyzing Transactions in Linked Value Chains of Wastewater Treatment and Crop ProductionMaaß, Oliver 12 July 2019 (has links)
In dieser Dissertation wird der Einfluss von Transaktionen zur Wiederverwendung von Nährstoffen und gereinigtem kommunalen Abwasser auf die Wertschöpfungsketten der Abwasserbehandlung und Pflanzenproduktion untersucht. Ziel ist es, Kosten und Nutzen sowie die Wertschöpfung von Transaktionen in verknüpften Wertschöpfungsketten der Abwasserbehandlung und Pflanzenproduktion zu analysieren. Darüber hinaus wird untersucht, wie Transaktionen und Interdependenzen zwischen Akteuren in verknüpften Wertschöpfungsketten die lokalen Governance-Strukturen für die Wiederverwendung von Abwasser beeinflussen. Die Analyse wird hauptsächlich durch das Wertschöpfungskettenkonzept, das Konzept der Kreislaufwirtschaft und die Theorie der Transaktionskostenökonomie geleitet. Mit verschiedenen Methoden, wie der Kosten-Nutzen-Analyse, der Wertschöpfungskettenanalyse und der Transaktionskostenanalyse, werden zwei Fallstudien in Deutschland untersucht: (1) die Fällung von Struvit (Magnesium-Ammonium-Phosphat) und dessen Verwendung als Dünger in Berlin-Brandenburg und (2) das Modell der landwirtschaftlichen Abwasserwiederverwendung in Braunschweig. Die Ergebnisse zeigen, dass die Wiederverwendung von Nährstoffen und Abwasser zu geringeren Kosten für die Abwasserbehandlung, höherer Rentabilität und Wertschöpfung in der Pflanzenproduktion und zu einem hohen Anteil an regionaler Wertschöpfung führen. Die Ergebnisse verdeutlichen aber auch, dass die Wiederverwendung von Abwasser zu Einschränkungen, Verdrängungseffekten und Veränderungen in der Verteilung der Wertschöpfung führen kann. Des Weiteren zeigen die Ergebnisse, dass differenzierte Governance-Strukturen erforderlich sind, um den unterschiedlichen Eigenschaften der Transaktionen zwischen Abwasserbehandlung und der Pflanzenproduktion gerecht zu werden. Interdependenzen zwischen Abwasseranbietern und Landwirten erhöhen den Bedarf an hybriden und hierarchischen Elementen in den Governance-Strukuren für die Wiederverwendung von Abwasser. / This dissertation explores the impact of transactions for reusing nutrients and treated municipal wastewater on the value chains of wastewater treatment and crop production. It aims to analyze what costs and benefits and what added-value can result from transactions in linked value chains of wastewater treatment and crop production. Furthermore, it aims to analyze how transactions and interdependences between actors in linked value chains shape the governance structures for reusing wastewater at the local level. The analysis is mainly guided by the value chain concept, the concept of the circular economy and the theory of transaction costs economics. Different methods including cost-benefit analysis, value chain analysis and transaction cost analysis are used to investigate two case studies located in Germany: (1) the precipitation of struvite (magnesium ammonium phosphate) in the wastewater treatment plant in Waßmannsdorf and its application as fertilizer in Berlin-Brandenburg, and (2) the agricultural wastewater reuse scheme of the Wastewater Association Braunschweig. The results show that transactions for reusing nutrients and wastewater result in the development of linked regional value chains with lower costs of wastewater treatment, higher profitability and added-value in crop production, and a high share of regional added-value. However, the results also highlight that the reuse of wastewater can lead to restrictions (e.g., cultivation bans on certain crops), crowding out effects and changes in the distribution of the added-value. Furthermore, the findings suggest that different governance structures are needed to match the different properties of the transactions between wastewater treatment and crop production. Interdependences resulting from transactions between wastewater providers and farmers increase the need for hybrid and hierarchical elements in the governance structures for reusing wastewater.
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