• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • Tagged with
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Resposta da mamoneira a doses de potássio, boro, zinco, cobre, magnésio e a fontes de nitrogênio / Response of castor bean to doses potassium, boron, zinc, copper, magnesium and nitrogen sources

Diógenes, Talita Barbosa Abreu 27 March 2012 (has links)
Made available in DSpace on 2016-08-31T13:15:06Z (GMT). No. of bitstreams: 1 TalitaBAD_DISSERT.pdf: 1199750 bytes, checksum: 6beacf2ab995069e2c168a6be1d1f249 (MD5) Previous issue date: 2012-03-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The production of castor bean in the Apodi Plateau can be used as an alternative to crop rotation schemes aimed at economic and environmental sustainability of areas traditionally cultivated cucurbits. For the castor produce satisfactorily, the adaptation to climate conditions and the use of appropriate farming is essential to have supplies of water and nutrients. In alkaline soils, the availability of some nutrients become limited, especially micronutrients; nitrogen, when applied in this type of soil can be quickly lost to the atmosphere by volatilization of ammonia, and the main occurrence of this loss occurs with the use of urea. This work aimed to evaluate the response of castor bean doses of potassium, boron, zinc, copper, magnesium and nitrogen sources applied at planting and coverage in order to contribute to the improvement of its productive system in the Apodi Plateau . In experiment 01, 10 treatments were compared regarding the soil application of five doses of potassium (0, 25, 50, 75 and 100 kg ha-1) and five doses of boron (0.0, 0.5, 1.0, 2.0 and 3.0 kg ha-1). In experiment 02, compared to seven treatments with the aim of evaluating the effects of the presence and absence of fertilization with Zn, Cu and Mg and the effects of forms of use (cultivation and or coverage) of N sources (urea and , or, ammonium sulfate). At 47 days after emergence composite samples were collected at depth 0-20 cm from the floor area of each plot, to determine the levels of K, Zn, Cu and Mg available. At the beginning of flowering of castor beans was assessed the nutritional status of plants, determining the K, B, Zn, Cu, Mg, S and N in the leaves. At the end of the experiment were evaluated: plant height, height of insertion of the primary raceme, stem diameter, number of racemes per plant, thousand grain weight of the raceme and primary and subsequent productivity. Under the experimental conditions, the average productivity of castor beans was 2.019 kg ha-1 grain, without requiring fertilization with potassium, boron, copper, zinc and magnesium, and indiscriminately using urea or ammonium sulfate as nitrogen source for crop fertilization and or cover, incorporated into the soil 5 cm in depth / A produção da mamona na Chapada do Apodi pode ser utilizada como alternativa para os sistemas de rotação de culturas que visem à sustentabilidade econômica e ambiental de áreas tradicionalmente cultivadas com cucurbitáceas. Para que a mamona produza satisfatoriamente, além de adaptação às condições edafoclimáticas e da utilização da cultivar adequada, é imprescindível que haja suprimentos de água e de nutrientes. Em solos alcalinos, a disponibilidade de alguns nutrientes torna-se restrita, principalmenteos micronutrientes; o nitrogênio, quando aplicado neste tipo de solo pode ser rapidamente perdido para atmosfera por volatilização da amônia, e a principal ocorrência dessa perda acontece com a utilização de uréia. Neste trabalho objetivou-se avaliar a resposta da cultura da mamona a doses de potássio, boro, zinco, cobre, magnésio e a fontes de nitrogênio aplicadas no plantio e em cobertura, de forma a contribuir para a melhoria do seu sistema produtivo na Chapada do Apodi. No experimento 01, foram comparados 10 tratamentos referentes à aplicação, no solo, de cinco doses de potássio (0, 25, 50, 75 e 100 kg ha -1) e cinco doses de boro (0,0, 0,5, 1,0, 2,0 e 3,0 kg ha -1). No experimento 02, compararam-se sete tratamentos, com o objetivo de avaliar os efeitos da presença e ausência de adubação com Zn, Cu e Mg e os efeitos de formas de utilização (plantio e, ou, cobertura) de fontes de N (uréia e, ou, sulfato de amônio). Aos 47 dias após a emergência foram coletadas amostras compostas de solo na profundidade de 0 a 20 cm da área útil de cada parcela, para determinação dos teores de K, Zn, Cu e Mg disponíveis. No início do florescimento da mamoneira foi avaliado o estado nutricional das plantas, determinando-se os teores de K, B, Zn, Cu, Mg, S e N nas folhas. Ao final do experimento, foram avaliadas a altura da planta, altura de inserção do racemo primário, o diâmetro do caule, número de racemos por planta, massa de mil grãos do racemo primário e subsequentes e produtividade. Nas condições experimentais, a produtividade média da mamoneira foi 2.019 kg ha-1 de grãos, sem necessitar de adubação com potássio, boro, cobre, zinco e magnésio, e utilizando indistintamente a uréia ou sulfato de amônio como fonte de nitrogênio para adubação de plantio e, ou, de cobertura, incorporada no solo a 5 cm de profundidade
2

Use Of Waste Pyrite From Mineral Processing Plants In Soil Remediation

Aydin, Gulsen 01 November 2011 (has links) (PDF)
Pyrite (FeS2) is commonly present in complex sulphide ores in significant amounts. After the enrichment of such ores by flotation, pyrite is either produced as a separate concentrate and sold to acid manufactures or removed and disposed off as tailing. Due to lack of demand from manufacturers, most of pyrites is usually disposed off as tailing. Therefore, pyrite is usually a waste from complex sulphide ores. Yet, it may be a remediation additive for calcareous soils and calcareous- alkali soils deficient in Fe and other micronutrients such as Cu, Zn and Mn. Waste pyrite may be also an alternative amendment to gypsum because of the production of sulphuric acid which is effectively used in the reclamation of calcareous alkali soils. The effectiveness of adding waste pyrite and sulphuric acid produced from waste pyrite to calcareous-alkali soil (Sarayk&ouml / y-Ankara) and calcareous soil (Gaziantep) was studied under laboratory conditions. Pure gypsum was also used as an amendment for the comparison of the effectiveness of waste pyrite in the reclamation of alkali soils. Gypsum, powder waste pyrite and sulphuric acid were applied to the soil with reference to the gypsum requirement (GR) of the soils. Greenhouse pot tests were carried out with wheat as test plant to determine the effect of waste pyrite treatment on the plant yield (wheat) and on the amount of micronutrient (Fe, Cu, Zn, Mn) essential for plant growth. Hazard potential of pyritic tailings in terms of heavy metal contamination was also taken into account. The results showed that the soil pH and exchangeable sodium percentage (ESP), indicators of alkalization, decreased upon pyrite addition to calcareous- alkali soils of Sarayk&ouml / y-Ankara. It was also found that pyritic tailings were effective in the increasing level of essential micronutrients (Fe, Cu, Zn and Mn) for plant growth in both soils. This was ascertained by the dry matter yield of the plants in the green house pot tests. Heavy metal toxicity caused by pyrite which is a rightful concern remained well below the legal limits in the soils. Thus, it was concluded that the application of pyritic tailings promoted rapid amelioration of calcareous-alkali soil (Sarayk&ouml / y-Ankara) and calcareous soil (Gaziantep) with no deleterious heavy metal contamination.

Page generated in 0.0682 seconds