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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.
1

Leucaena/millet alley cropping in India : microclimate and productivity

Corlett, Janet E. January 1989 (has links)
No description available.
2

Evaluating Productivity of Southern Agroforestry for Fiber, Biofuels, and Wildlife Habitat

Gordon, Henry Gill 14 August 2015 (has links)
Wildlife habitat values associated with agroforestry systems in Mississippi are not fully understood. Landscape matrix changes resulting in close location of various agricultural and tree crops can provide habitat more suitable for use by game wildlife. This study examined the feasibility of improving habitat value by adopting agroforestry alley cropping practices. A completely randomized block design was utilized to ascertain production values for two different even-aged crop trees, shortleaf pine (Pinus echinata Mill.) and loblolly pine (Pinus taeda L.), and four different agricultural crops, corn (Zea mays L.), switchgrass (Panicum virgatum L.), grain sorghum (Sorghum bicolor L.), and soybeans (Glycine max L.). Breeding bird surveys and camera surveys were used to quantify wildlife use and determine habitat improvement produced by this agroforestry management. If agroforestry land management improves wildlife habitat quality so hunters are willing to pay higher premiums, landowners can generate additional economic return from hunting leases.
3

Effects of alley cropping systems on yield and nutrition of forage crops in Saskatchewan

2013 December 1900 (has links)
The agroforestry practice of establishing shelterbelts and/or windbreaks composed of tree and shrub species that include buffaloberry (Shepherdia argentea Nutt.), caragana (Caragana arborescens Lam.) and sea buckthorn (Hippophae rhamnoides L.) is widespread within Saskatchewan. Shelterbelts play major roles in reducing wind speed, trapping snow, improving land-use efficiency and increasing economic returns. However, the practice of alley cropping within Saskatchewan is not popular. Also, apart from the protective roles the tree species offer in shelterbelts, some species have atmospheric nitrogen (N2)-fixation capabilities through biological nitrogen fixation (BNF) that are potentially important. The simultaneous integration of trees and crops on the same land management unit may lead to competition between crops and trees for growth resources such as nutrients, soil moisture and incoming radiation, the latter leading to limited access of light for understory crops. Understanding the contributions of the trees in supplying nitrogen (N) through BNF and in modifying microclimatic conditions in the alleyways would generate information needed to know their impacts on yield and nutrition of associated crops. In order to assess the contribution of the tree species in supplying N and minimizing interspecific competition while maximizing the benefits of tree-based intercropping systems, the thesis quantified the BNF capabilities of each species under greenhouse conditions using 15N dilution techniques and assessed how much of the fixed N2 is transferred to associated triticale (Triticale hexaploide Lart.) and oats (Avena sativa L.) under field conditions. Growth and yield of oats was also studied by measuring photosynthetically active radiation (PAR) and soil moisture in a Manitoba maple (Acer negundo var. negundo L.) -oats alley cropping system at Indian Head, SK. The BNF results showed that each of the test species fixes a substantial amount of N and there was a high transfer of N to associated triticale and oats. Results from the interspecific interaction study also showed that soil moisture was the primary factor affecting oats yields followed by light, with the south-lying oat plants affected more than north-lying. It can be concluded that alley cropping systems can be a practical and beneficial agroforestry practice within Saskatchewan. However, the distance between tree rows should be wide enough to permit farm machinery operations.
4

Produ??o de helic?nia Golden Torch sob cultivo em al?ias. / Production of Heliconia Golden Torch under alley cropping.

Cirqueira, Andr? Luiz Oliveira 29 October 2009 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-08-22T15:27:16Z No. of bitstreams: 1 2009 - Andre Luiz Oliveira Cirqueira.pdf: 2107082 bytes, checksum: 332d5419e8942ce8ee1ccd478e906c34 (MD5) / Made available in DSpace on 2017-08-22T15:27:16Z (GMT). No. of bitstreams: 1 2009 - Andre Luiz Oliveira Cirqueira.pdf: 2107082 bytes, checksum: 332d5419e8942ce8ee1ccd478e906c34 (MD5) Previous issue date: 2009-10-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil. / Tropical flower production has growing in Brazil, mostly by the recent interest of flower consumers on products with exotic shapes, vibrant colors and high durability. These flowers, not usual in Brazil, are still produced on low scale. Production systems have not been intensively exploited, as well as basic studies with the various varieties and species have not been conducted. Production systems that combine economic feasibility with low environmental impact should de developed for this plant group, since they adapt to a wide range of environmental conditions, including shade. Environment adaptation studies combined with mineral nutrition studies are necessary to understand and improve integrated tropical flower production, using other pla nt species under various environmental conditions. Alley cropping, used on this study, is an example of such integration. This research evaluated the performance of hybrid heliconia Golden Torch (Heliconia psittacorum L x Heliconia spathocircinada Aristigueta) under alley cropping with pigeonpea (Cajanus cajan (L.) Millsp.) and Flemingia macrophylla and a control treatment. Two rates of thermophosphate (Yorin Master 1) ? with or without, were combined to the previous treatments. The experiment was conducted at the Crop Science Department of Universidade Federal Rural do Rio de Janeiro. The experimental design was a split plot in complete randomized design. Lower heliconia mortality occurred on alleys formed by Cajanus cajan. Phosphate addition did not affect mortality. Higher yields of heliconia flowers were observed on Flemingia macrophylla alleys, followed by Cajanus cajan and control. Phsophate addition did not affect yields. Number of lateral shoots was affected by the plant position on the plot: central rows tended to have more shoots than lateral rows. Leaf area was higher where phosphate was applied, independently of alley cropping. / A floricultura tropical tem se projetado no Brasil, principalmente pelo recente interesse dos consumidores de flores, por produtos de formas ex?ticas, cores vibrantes e alta durabilidade. Essas flores, pouco tradicionais no Brasil, s?o produzidas ainda em pequena escala. Seus sistemas de produ??o ainda n?o foram intensivamente estudados, bem como estudos b?sicos envolvendo as muitas esp?cies e variedades ainda est?o por ser feitos. Sistemas de produ??o que conciliem viabilidade econ?mica com baixo impacto ambiental, devem ser desenvolvidos para esse grupo de plantas, visto que se adaptam a uma gama de condi??es ambientais, incluindo sombreamento. Estudos de ambi?ncia combinados aos de nutri??o mineral s?o necess?rios para se entender e aperfei?oar uma forma de floricultura tropical integrada a outras esp?cies, em diferentes condi??es edafoclim?ticas. Um exemplo ? o sistema de cultivo em al?ias, objeto deste estudo. Este trabalho teve como objetivo avaliar o comportamento do hibrido natural Golden Torch (Heliconia psittacorum L x Heliconia spathocircinada Aristigueta) cultivada sob sistema de cultivo em al?ias formadas por dois tipos de leguminosas arbustivas: guandu (Cajanus cajan (L.) Millsp.) e flem?ngia (Flemingia macrophylla), e um controle sem forma??o de al?ias. Combinou-se ainda, dois tipos de aduba??o de plantio: com e sem termofosfato magnesiano (Yoorin Master 1). O experimento foi conduzido nas condi??es da Baixada Fluminense no Campus da UFRRJ, Departamento de Fitotecnia, num delineamento de parcelas subdivididas em blocos ao acaso. Houve menor mortalidade de plantas nas al?ias formadas por guandu quando comparada com as formadas por flem?ngia ou no tratamento controle. A aplica??o de termofosfato n?o teve qualquer efeito. A maior produtividade de infloresc?ncias ocorreu nas al?ias formadas por flem?ngia, seguida pelo guando e a testemunha. A adi??o de termofosfato n?o afetou a produ??o de infloresc?ncias. O n?mero de perfilhos, foi afetado pela posi??o da planta na parcela: as da linha central tenderam a ter mais perfilhos do que as laterais. A ?rea foliar das plantas de helic?nia foi maior nos tratamentos com termofosfato, independentemente do tipo de al?ia.
5

Sustentabilidade do sistema plantio direto em argissolo no trópico úmido

Aguiar, Alana das Chagas Ferreira [UNESP] 10 November 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-10Bitstream added on 2014-06-13T18:40:32Z : No. of bitstreams: 1 aguiar_acf_dr_botfca.pdf: 805231 bytes, checksum: 691481c78e5e608342cb3c11587eccca (MD5) / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico do Maranhão (FAPEMA) / Os objetivos do presente estudo foram: (i) avaliar a sustentabilidade do agrossistema de plantio direto na palha com leguminosas cultivadas em aléias, por meio de seu efeito sobre os indicadores qualitativos químicos e físicos de um Argissolo do trópico úmido; (ii) identificar como a combinação de resíduos de leguminosas de diferentes qualidades interferem nos indicadores de sustentabilidade do uso do solo, por meio das produtividades do arroz e do milho. Foram avaliadas duas espécies de leguminosas de alta qualidade de resíduos - Leucaena leucocephala (leucena) e Cajanus cajan (guandu), e duas espécies de baixa qualidade de resíduos - Clitoria fairchildiana (sombreiro) e Acacia mangium (acácia), combinadas entre si, nos seguintes tratamentos: Sombreiro + Guandu (S+G); Leucena + Guandu (L+G); Acácia + Guandu (A+G); Sombreiro + Leucena (S+L); Leucena + Acácia (L+A) e Testemunha, sem leguminosas. Concluiu-se que o sistema de plantio direto na palha com leguminosas cultivadas em aléias pode ser considerado alternativa de uso sustentável do solo nas condições de regime pluviométrico e nos ARGISSOLOS arênicos, por sua capacidade de reciclar nutrientes e melhorar os indicadores de qualidade do solo ao longo do tempo. Os principais indicadores influenciados pelo sistema são: a capacidade de aeração, as quantidades de N adicionadas ao solo via resíduos de leguminosas e o tamponamento dos teores de Ca na zona radicular que resultam na melhoria na qualidade do solo, com reflexos notáveis no aumento da produtividade do milho. A combinação acácia+leucena apresenta, além da precocidade, grande eficiência na cobertura do solo e na reciclagem de nutrientes, mas o uso do sombreiro, como fornecedora de resíduo de baixa qualidade, por sua facilidade de 2 implantação, não pode ser descartado. A incapacidade do sistema em aumentar a retenção do K e Mg na zona radicular... / The present study was carried out focused in the following subjects: (i) Evaluation of no tillage agriculture sustainability over green manure straws in alley system throughout of its effects on the soil s chemical and physical qualitative parameters; (ii) Identification of what and how different green manure residues combine each other to improve the rice and corn crops in sustainability alleys system way. Two green manure species with high residues and other two with low quality had been evaluated: Leucaena leucocephala and Cajanus cajan, and Clitoria fairchildiana and Acacia mangium respectively. A combination between these green manures were made as the treatments: Clitoria + Cajanus (S+G); Leucaena + Cajanus (L+G); Acacia + Cajanus (A+G); Clitoria + Leucaena (S+L); Leucaena + Acacia (L+A) and the control treatment with no green manure. It was concluded that the no tillage soil management using green manure straws in alleys systems could be an alternative as a sustainable way to the crop productions, considering the environments and soil conditions. It was observed that the soil where the trial was carried out has the capacity to recycle nutrients and improve the quality parameters throughout the management used as far. It was observed also that the mainly parameters as aeration capacity, nitrogen range added by the green manure of leguminous species residues, and the Ca++ content in the rizosphere environment were the factors that improve the soil physical and chemical quality, with higher corn crop productivities. The Leucaena + Acacia combination has shown precocious behavior and more efficiency to cover the soil and to recycle nutrients. The Clitoria residues, even as a low quality green manure, could be na option for implanting a alley system because it is easier to 4 management. It was observed that the studied system has no capacity of K+ and Mg++ retain... (Complete abstract, click electronic address below)
6

O cultivo da cana-de-açúcar em aleias: produtividade agrossilvicultural e influências sobre o agroecossistema / Sugarcane farming in alley cropping system: agroforestry productivity and influences in the agroecosystem

Pereira, Virgílio de Almeida 04 December 2013 (has links)
Made available in DSpace on 2016-06-02T18:57:49Z (GMT). No. of bitstreams: 1 5731.pdf: 10443315 bytes, checksum: 6ee3add6c6df69821536597088d1b32d (MD5) Previous issue date: 2013-12-04 / Universidade Federal de Sao Carlos / Sugarcane plantations are increasing in Brazil motivated by the demand of the sugar industry and the energetic sector. Sugarcane monocultures simplify the landscape and disconnect natural ecosystems. The inclusion of native trees in the canebrake, changing the matrices into an alley cropping system, is a new proposal that consider the environment beyond production. In order to assess the environmental effects in agroforestry was raised sugarcane productivity and development of trees in three crops (2009/10, 2010/11 and 2011/12), as well as the timber volume and carbon sequestration produced by the system at the end of the year 2012 and a bird survey during 2011 and 2012 in an experimental area of 1,957 hectares. Was found orderly development of tree species. Schizolobium parahyba present a significant mortality, but had the largest wood production thus coming to the same conclusion in relation to carbon sequestration, which are 3 times those of the Handroanthus spp. and 2 times the Cedrela fissilis. There was no change in the sugarcane productivity related to the distance line planting was the alley, with only a drop productivity in the range of 58 m cultivation. Birds are important bioindicators; trees contributed to the increased diversity of birds, being Schizolobium parahyba the arboreal species of most relevant importance. The spacing between alleys with the greatest diversity of birds was to 29 m. It is concluded that it is technically possible deployment agroecosystem proposed, without agronomic production damage of cane sugar; the 2 smaller bands cultivation (29 m and 43.5 m) are the most suitable; among tree species Schizolobium parahyba was the one with the best results in the short term, since the issue of mortality could be remedied with proper management or replanting. / O plantio de cana-de-açúcar está em franca expansão no Brasil motivado pela demanda do setor sucroenergético. Os canaviais em matrizes monoculturais simplificam a paisagem e desconectam ecossistemas naturais. A inserção de aleias com árvores nativas em canavial é uma nova proposta que contempla o ambiente além da produção. Com o objetivo de avaliar os efeitos ambientais e a produtividade agrossilvicultural nesse sistema agroflorestal, foram levantados em uma área experimental de 1,957 hectares, o rendimento da cana-de-açúcar e o desenvolvimento das árvores constituintes das aleias em 3 safras (2009/10, 2010/11 e 2011/12); bem como o volume de madeira produzido e a fixação de carbono pelo sistema ao final do ano de 2012; e a dinâmica da avifauna durante os anos de 2011 e 2012. Constatou-se um desenvolvimento regular das espécies arbóreas, observando grande taxa de mortalidade do guapuruvu (60%). Foi possível constatar a maior produção de madeira pelo guapuruvu, consequentemente chegando aos mesmos resultados em relação à fixação de carbono, sendo estes 3 vezes superiores aos do ipê e 2 vezes ao cedro. A produtividade da cana não esteve relacionada com a distância entre a linha de plantio e a aleia, apresentando queda apenas na faixa de cultivo de 58 m. A avifauna foi considerada um bioindicador consistente; o guapuruvu foi a espécie florestal com maior importância para o aumento da diversidade de aves e o espaçamento entre aleias com a maior riqueza foi o de 29 m. Conclui-se que é tecnicamente possível a implantação do agrossistema proposto, sem prejuízo agronômico da produção da cana-de-açúcar, sendo as 2 menores faixas de cultivo (29 e 43,5 m) as mais propícias e o guapuruvu a espécie arbórea com melhores resultados em curto prazo, desde que a questão da mortalidade seja sanada com replantio ou manejo adequado.
7

The Adoption of Legumes in Farmer and Consumer Settings

Lemken, Dominic 14 November 2017 (has links)
No description available.
8

Relationships Among Soil Properties and Soil CO2 Efflux in a Loblolly Pine-Switchgrass Intercropped System

Nichols, Lara Kaitlin 05 November 2013 (has links)
The components of soil CO2 efflux are affected by many soil properties including temperature, moisture, microbial abundance and activity, and other soil physical and chemical properties. Changes in these factors can result in high spatial and temporal variability of total soil CO2 efflux. Low molecular weight organic acids (LMWOAs), dissolved organic carbon (DOC) and dissolved organic nitrogen (DON), microbial biomass and activity were measured to evaluate the impact of intercropping switchgrass (Panicum virgatum L.) in a loblolly pine (Pinus taeda L.) plantation. Surface soil samples (0-15 cm) were collected on the bed (PSG-B), interbed (PSG-I) and edge (PSG-E) of pine-switchgrass intercropped treatments, as well as pine only (P-B) and switchgrass only (SG-I) treatments. Differences in most soil properties and processes of intercropped treatments were sporadic and most did not show clear trends. However, significant correlations between DOC, soil temperature, oxalic and acetic acids and soil CO2 efflux were present. In an multiple regression model these factors explained 57% of the variance in total soil CO2 efflux. Therefore we think that LMWOAs, as a labile component of DOC, are influencing total CO2 efflux because they are being consumed by microbial community, increasing heterotrophic respiration and as a result overall total CO2 efflux. The amount and distribution of labile C controls microbial community dynamics, heterotrophic respiration as well as the stabilization of soil C. / Master of Science
9

Soil-water use and irrigation scheduling under fruit tree-turf alley cropping system in Hawkesbury Area

Hasnat, Abul, University of Western Sydney, College of Science, Technology and Environment, School of Environment and Agriculture January 2003 (has links)
Efficient use of irrigation and nutrients are becoming increasingly important in commercial orchards in the Hawkesbury area. Proper irrigation scheduling practices can help in the better use of irrigation water and reduce environmental impacts. Field experiments were conducted during February 1999 to June 2000 to understand soil-water use, and to evaluate farmer’s irrigation practice under an alley cropping system consisting of turf and stone fruits. The study was carried out at Atlas Farm, 3.5 km from the University of Western Sydney, Hawkesbury campus. The experimental site is a floodplain of the Hawkesbury River. The river flows within 1 km of the farm boundaries. The study was conducted under the farmer’s existing irrigation water and nutrient management practices. The main aims of the thesis were to study the movement and redistribution of soil-water and soil-moisture dynamics in the turf and stone fruit alley cropping system and to understand deep percolation losses and nitrogen leaching using the water balance approach. The study indicated that drainage occurred mainly after heavy rainfall and when there was rainfall for a few consecutive days. Thus irrigation application should be delayed if there is a likelihood of rain in a few consecutive days to prevent loss of water due to deep drainage. Furthermore, the study showed irrigation scheduling was essential to reduce nitrate leaching in the field; that irrigation depths should be varied according to the stage of crop growth, and the proper timing of irrigation application could help reduce deep percolation and runoff losses. / Master of Science (Hons) (Agriculture)
10

Sustentabilidade do sistema plantio direto em argissolo no trópico úmido /

Aguiar, Alana das Chagas Ferreira, 1975- January 2006 (has links)
Resumo: Os objetivos do presente estudo foram: (i) avaliar a sustentabilidade do agrossistema de plantio direto na palha com leguminosas cultivadas em aléias, por meio de seu efeito sobre os indicadores qualitativos químicos e físicos de um Argissolo do trópico úmido; (ii) identificar como a combinação de resíduos de leguminosas de diferentes qualidades interferem nos indicadores de sustentabilidade do uso do solo, por meio das produtividades do arroz e do milho. Foram avaliadas duas espécies de leguminosas de alta qualidade de resíduos - Leucaena leucocephala (leucena) e Cajanus cajan (guandu), e duas espécies de baixa qualidade de resíduos - Clitoria fairchildiana (sombreiro) e Acacia mangium (acácia), combinadas entre si, nos seguintes tratamentos: Sombreiro + Guandu (S+G); Leucena + Guandu (L+G); Acácia + Guandu (A+G); Sombreiro + Leucena (S+L); Leucena + Acácia (L+A) e Testemunha, sem leguminosas. Concluiu-se que o sistema de plantio direto na palha com leguminosas cultivadas em aléias pode ser considerado alternativa de uso sustentável do solo nas condições de regime pluviométrico e nos ARGISSOLOS arênicos, por sua capacidade de reciclar nutrientes e melhorar os indicadores de qualidade do solo ao longo do tempo. Os principais indicadores influenciados pelo sistema são: a capacidade de aeração, as quantidades de N adicionadas ao solo via resíduos de leguminosas e o tamponamento dos teores de Ca na zona radicular que resultam na melhoria na qualidade do solo, com reflexos notáveis no aumento da produtividade do milho. A combinação acácia+leucena apresenta, além da precocidade, grande eficiência na cobertura do solo e na reciclagem de nutrientes, mas o uso do sombreiro, como fornecedora de resíduo de baixa qualidade, por sua facilidade de 2 implantação, não pode ser descartado. A incapacidade do sistema em aumentar a retenção do K e Mg na zona radicular... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study was carried out focused in the following subjects: (i) Evaluation of no tillage agriculture sustainability over green manure straws in alley system throughout of its effects on the soil’s chemical and physical qualitative parameters; (ii) Identification of what and how different green manure residues combine each other to improve the rice and corn crops in sustainability alleys system way. Two green manure species with high residues and other two with low quality had been evaluated: Leucaena leucocephala and Cajanus cajan, and Clitoria fairchildiana and Acacia mangium respectively. A combination between these green manures were made as the treatments: Clitoria + Cajanus (S+G); Leucaena + Cajanus (L+G); Acacia + Cajanus (A+G); Clitoria + Leucaena (S+L); Leucaena + Acacia (L+A) and the control treatment with no green manure. It was concluded that the no tillage soil management using green manure straws in alleys systems could be an alternative as a sustainable way to the crop productions, considering the environments and soil conditions. It was observed that the soil where the trial was carried out has the capacity to recycle nutrients and improve the quality parameters throughout the management used as far. It was observed also that the mainly parameters as aeration capacity, nitrogen range added by the green manure of leguminous species residues, and the Ca++ content in the rizosphere environment were the factors that improve the soil physical and chemical quality, with higher corn crop productivities. The Leucaena + Acacia combination has shown precocious behavior and more efficiency to cover the soil and to recycle nutrients. The Clitoria residues, even as a low quality green manure, could be na option for implanting a alley system because it is easier to 4 management. It was observed that the studied system has no capacity of K+ and Mg++ retain... (Complete abstract, click electronic address below) / Orientador: Silvio José Bicudo / Coorientador: Emanoel Gomes de Moura / Banca: Dirceu Maximino Fernandes / Banca: Iraê Amaral Guerrini / Banca: Edmilson José Ambrosano / Banca: Ricardo Augusto Dias Kanthack / Doutor

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