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  • 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.
141

Quantification of the belowground inputs of organic carbon by the annual pasture legume barrel medic (Medicago truncatula Gaertn.) / by Michael Cameron Crawford.

Crawford, Michael Cameron January 1997 (has links)
Bibliography: leaves 164-193. / x, 193 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study aims to quantify the belowground input of organic carbon by barrel medic using techniques that account for root death and decomposition as well as root secretion and exudation. It also investigates the effect of defoliation on carbon allocation within the plant so as to determine the potential for optimising carbon input to the soil through grazing management. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1997
142

Quantification of the belowground inputs of organic carbon by the annual pasture legume barrel medic (Medicago truncatula Gaertn.) / by Michael Cameron Crawford.

Crawford, Michael Cameron January 1997 (has links)
Bibliography: leaves 164-193. / x, 193 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study aims to quantify the belowground input of organic carbon by barrel medic using techniques that account for root death and decomposition as well as root secretion and exudation. It also investigates the effect of defoliation on carbon allocation within the plant so as to determine the potential for optimising carbon input to the soil through grazing management. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1997
143

Improved soil and water conservatory managements for cotton-maize rotation system in the western cotton area of Burkina Faso /

Ouattara, Korodjouma, January 2007 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2007. / Härtill 3 uppsatser.
144

Ecology of urban lawns the impact of establishment and management on plant species composition, soil food webs, and ecosystem functioning /

Cheng, Zhiqiang , January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 140-151).
145

Behaviour of alkaline sodic soils and clays as influenced by pH and particle change /

Chorom, Mostafa. January 1996 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Soil Science. / Copies of author's previously published articles inserted. Includes bibliographical references (leaves 173-196).
146

Comparative effects of nitrogen phosphorus and the micronutrients on rice and oats on a lateritic soil.

Kanapathy, Kandasamy. January 1955 (has links) (PDF)
Thesis (B. Sci. (Hons.))--University of Adelaide, Faculty Agricultural Science,1955. / Typewritten copy. Includes bibliographical references.
147

Assessing soil microbial populations and activity following the use of microbial inoculants effect on disease suppressiveness and soil health /

Cadena Cepeda, Marleny, Kloepper, Joseph. January 2006 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.
148

Alteration of the soil mantle by strip mining in the Namaqualand Strandveld /

Prinsloo, H. P. January 2005 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.
149

Implantação da cultura de cana-de-açúcar em argissolo vermelho do noroeste paulista: preparo do solo e uso de gesso

Lima, Ronaldo Cintra [UNESP] 24 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-24Bitstream added on 2014-06-13T19:46:49Z : No. of bitstreams: 1 lima_rc_dr_ilha.pdf: 738012 bytes, checksum: 95545f96fb6fc56b4df32a87c95e8362 (MD5) / Universidade Estadual Paulista (UNESP) / A cana-de-açúcar se destaca como sendo uma importante cultura do mundo tropical, e em especial para o Brasil que vem se destacando como o maior produtor mundial. A demanda crescente, no mercado interno e externo, por combustíveis renováveis, especialmente o Etanol, passou a atrair investimentos para a implantação de novas áreas de cana-de-açúcar para atender a indústria. A inclusão de novas regiões no processo produtivo de cana-de- açúcar, requer maior atenção aos fatores de produção, dentre eles o manejo e correção dos solos, pois é imprescindível a eliminação de impedimentos físicos e químicos do solo, causados por camadas compactadas, toxidez por alumínio, acidez e teores inadequados de cálcio e outros nutrientes. Para tanto, a escolha da modalidade e equipamento de preparo do solo mais adequado, além do uso de corretivos de acidez e condicionador de subsuperfície do solo, é de grande importâcia para proporcionar um ambiente mais propício para que a cultura da cana-de-açúcar desenvolva-se e expresse o seu potencial produtivo. O trabalho foi conduzido em área de implantação de cana-de-açúcar, anteriormente ocupada com pastagem há mais de 15 anos, da Usina Vale do Paraná no município de Suzanápolis - SP, região do Noroeste Paulista. Foi utilizada a variedade RB92-5345 com espaçamento de 1,5 m entrelinhas, em Argissolo Vermelho Distrófico abrúptico textura arenosa/média. O delineamento experimental utilizado foi de blocos ao acaso, com seis tratamentos, em esquema fatorial 3 x 2 e seis repetições, sendo os tratamentos constituídos por preparo de solo com três modalidades: arado de aivecas, escarificador e grade pesada; com (1 t ha-1) de gesso e sem gesso. O trabalho objetivou avaliar qual sistema de preparo do solo, com e sem uso de gesso proporciona melhores... / The sugarcane stands out as being an important crop in the tropical world, and especially to Brazil that has emerged as the largest producer. The increasing demand in domestic and foreign markets for renewable fuels, especially ethanol, began to attract investments to roll out new areas of sugarcane to meet the needs of industry. The inclusion of new regions in the productive process of `sugarcane requires greater attention to factors of production, including management and correction of soil, it is necessary to eliminate physical and chemical impediments of the soil, caused by compacted layers, aluminum toxicity, acidity, and inadequate levels of calcium and other nutrients. To this end, the choice of modality and tillage equipment most appropriate, besides the use of corrective agents of acidity and subsurface soil conditioner is of great importance to provide a more favorable environment for sugarcane crop develop itself and to express their productive potential. The experiment was conducted in an area of expansion of sugarcane at Usina Vale do Paraná in the city Suzanápolis - SP, in the Northwest of Sao Paulo in the area previously occupied by grazing for over 15 years. In the implementation of crop was used variety RB92-5354 at a spacing of 1.5 m between rows in Red Argisol Dystrophic abrupt sandy texture / medium. The experimental design used was a randomized block design with six treatments in a factorial scheme 3 x 2 and six repetitions, and the main treatments consisting of soil preparation with three modalities: moldboard plow, chisel plow and harrow and two secondary treatments with (1 t ha -1) and without gypsum. The study aimed to evaluate which system of tillage, with and without the use of gypsum provides better conditions for development and technological qualities in the sugarcane crop. For this... (Complete abstract click electronic access below)
150

Boro em trevo: eficiência de extratores e efeito sobre atributos químicos do solo, em área com e sem corte da parte áerea submetida a níveis de b

Batista, Cíntia Boeira January 2011 (has links)
Recentemente pesquisas têm se voltado à importância dos micronutrientes na nutrição mineral de plantas. Entretanto, há uma enorme dificuldade na quantificação de micronutrientes pela análise química do solo devido à baixa confiabilidade dos métodos. Muitos extratores utilizados pelos laboratórios de análises não possuem uma satisfatória correlação com as quantidades encontradas nas análises de foliar. Este estudo, além de avaliar extratores de solo para B, buscou igualmente avaliar o efeito do manejo do corte e remoção da parte aérea do trevo branco (Trifolium repens L.) sobre as características químicas do solo. Assim, este trabalho pretende: 1º- estudar a eficiência de soluções extratoras compostas por sulfato de alumínio, água quente, sorbitol e Mehlich1 na avaliação quantitativa de boro no solo e a eficiência dos extratores quando correlacionados com os resultados de boro foliar contido na cultura de trevo branco 2º- avaliar a influência do manejo de corte e remoção da parte aérea do trevo branco sobre as características químicas do solo. À campo o trevo-branco foi conduzido na Estação Experimental do Instituto Agronômico do Paraná – IAPAR, localizada no Município de Pato Branco – PR. A área experimental está localizada na região fisiográfica denominada Terceiro Planalto Paranaense. O solo é classificado como LATOSSOLO VERMELHO distroférrico relevo ondulado textura argilosa (EMBRAPA, 2008). O delineamento experimental foi blocos ao acaso com quatro repetições, sendo as parcelas constituídas de quatro coletas, as sub parcelas foram os tratamentos com doses crescentes de boro (0; 0,5; 1; 2 e 4 kg ha-1) na forma de ulexita (10% de B). As sub – sub parcelas foram as diferentes profundidades de solo avaliadas (0–5; 5–10 e 10- 20 cm). As amostras de solo e planta foram coletadas bimestralmente sendo que a planta foi enviada para o Laboratório do IAPAR em Londrina para determinação de teores de boro foliar. Enquanto que, as amostras de solo foram analisadas no Laboratório de Solos da UTFPR – Câmpus Pato Branco. Para a avaliação do segundo experimento foi utilizado delineamento de blocos ao acaso subdivididas com quatro repetições. O tratamento do manejo de corte e sem o corte da parte aérea do trevo branco foi considerado como a parcela e que teve como sub – parcela o tratamento de cinco doses de B (0, 0,5;1,0;2,0 e 4,0 kg ha-1, utilizando solução de Ulexita 10% B) e as sub – sub - parcelas foram constituídas pelas profundidades de amostragem de solo (0-5; 5-10 e 10-20 cm ). As metodologias utilizadas para as análises químicas de rotina do solo seguem Manual de Análise Química de Solo e Controle de Qualidade do IAPAR (1992), para as análises de extração e quantificação de B no solo e na planta utilizou-se EMBRAPA (2009). Com a primeira avaliação constata-se que o Al2(SO4)3 0,005M foi o extrator que apresentou maiores valores de correlação entre os valores do nutriente na planta com o valores do mesmo no solo de 0,92. Verificou-se que a Ulexita apresenta uma liberação lenta do nutriente B no solo sendo que os maiores teores de recuperação de B no solo pelos diversos extratores foram observados, em geral, após seis meses de aplicação. Na segunda avaliação verifica-se que a remoção constante da parte aérea de forrageiras provoca acidificação do solo e maior extração de bases, sendo assim, sistemas de produção de silagem e de feno devem constantemente repor bases ao solo via calagem. / Recently studies have been directed to the importance of micronutrients in plant mineral nutrition. However, there is great difficulty in quantifying micronutrients by chemical analysis of soil due to low reliability of the methods. Extractors used by many laboratories do not have a satisfactory correlation with the amounts found in the analysis of leaf. This study, besides evaluating extractors for soil B, also sought to evaluate the effect of handling the cutting and removal of the aerial part of white clover (Trifolium repens L.) on soil chemical properties. This work aims to: 1ª - to study the efficiency of extraction solutions consisting of aluminum sulfate, sorbitol and Mehlich1 the quantitative assessment of boron in soil and efficiency of extractors when correlated with the results of boron leaf contained in the culture of white clover 2ª - evaluate the influence of the management of cutting and removing the aerial part of white clover on soil chemical properties. In the field the white clover was conducted at the Experimental Station of the Agronomic Institute of Paraná - IAPAR, located in the city of Pato Branco - PR. The experimental area is located in the physiographic region called the Third Paranaense Plateau. The soil is classified as Oxisol clayey wavy relief (EMBRAPA, 2008). The experimental design was randomized blocks with four replications, and plots consist of four collections, the sub plots were the treatments with increasing doses of boron (0, 0.5, 1, 2 and 4 kg ha-1) in the form of ulexite (10% of B). The sub - sub plots were the different soil depths evaluated (0-5, 5-10, 10-20 cm). The soil and plant samples were collected every two months that the plant was being sent to the Laboratory in Londrina IAPAR to determine levels of boron leaf. While the soil samples were analyzed at the Laboratory of Soil UTFPR - Campus White Duck. To evaluate the second experiment was used a randomized block design with four replications subdivided. The samples were treated as two parts, sub-plots were cut and management without cutting the shoots of white clover, sub plots were treated as five doses of B (0, 0.5, 1.0 , 2.0 and 4.0 kg ha-1, using 10% solution Ulexite B) and sub - sub - plots were set up by soil sampling depths (0-5, 5-10 and 10-20 cm). The methodologies used for routine chemical analysis of soil following IAPAR (1992), as well as the analysis of extraction and quantification of B in soil and plant. With the first evaluation finds that the Al 2 (SO4) 3 0.005 M was the extractor that presented higher correlation values between the values of the nutrient in the plant with the same values in the soil of 0.92. It was found that the Ulexite has a slow release of nutrients in the soil B with the highest levels of recovery of B in the soil by different extractants were observed, usually after six months of application. In the second evaluation verifies that the constant removal of the aerial parts of forage causes soil acidification, an increase of toxic elements such as Al and extraction of bases, so production systems of silage and hay must constantly replenish the soil bases through liming.

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