oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Viabilidade Econ mica de Sistemas Silvipastoris com Schizolobium parahyba var. amazonicum e Tectona grandis no Pará Economical Viability of Silvopastoral Systems with Schizolobium parahyba var. amazonicum Barneby and Tectona grandis in Para, Brazil  [cached]
Rosana Quaresma Maneschy,Ant?nio Cordeiro de Santana,Jonas Bastos da Veiga
Pesquisa Florestal Brasileira , 2010, DOI: 10.4336/2012.pfb.60.49
Abstract: Os sistemas silvipastoris (SSPs) consistem de um conjunto de metodologias que podem ser consideradas promissoras para recuperar áreas de pastagens degradadas da Amaz nia, por integrar o cultivo arbóreo ao pecuária tradicional. Embora já utilizados em pequena escala por produtores inovadores, os SSPs carecem de uma base científica que forne a subsídios técnicos ao seu uso mais amplo, sobretudo quando se trata de justificar a viabilidade econ mica desses sistemas. O objetivo desse estudo foi analisar a viabilidade econ mica de SSPs utilizados por produtores no nordeste do Estado do Pará, comparando-os ao monocultivo tradicional. Os sistemas s o compostos basicamente pelo paricá (Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby) ou teca (Tectona grandis L.F.), em pastagens de quicuio-da-amaz nia (Brachiaria humidicola (Rendle) Schweick) pastejados por bovinos. A análise de viabilidade econ mica foi realizada por meio dos métodos: valor presente líquido (VPL), taxa interna de retorno (TIR) e rela o benefício/custo (Rb/c), considerando quatro SSPs e o monocultivo de paricá e teca. Os sistemas compostos por teca apresentam maior atratividade econ mica do que os com paricá, e dentre eles, os arranjos silvipastoris, em que o gado era próprio, foram considerados de melhor viabilidade que os sistemas em monocultivo ou em que a incorpora o animal se dava através do aluguel da pastagem. doi: 10.4336/2009.pfb.60.49 The silvopastoral systems (SPSs) have been considered promising to integrate tree crops in livestock production systems and reclain large areas of degraded pastures of the Brazilian Amazon. They are used on small scale by innovative farmers, the SPSs lack a scientific basis to provide technical subsidies to its wider use, especially when it comes to justifying the economic viability of these systems. The objective of this study was to analyze the economical viability of SPSs, established in farms areas used by producers in the Northeast State of Para and comparing to the traditional monoculture. The systems are composed basically by parica (Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby) or teak (Tectona grandis L. F.) in kikuyu grass (Brachiaria humidicola (Rendle) Schweick) under cattle grazing. The analysis of economical viability was realized by the indicators: net present value (NPV), internal rate of return (IRR) and benefit-cost ratio (Rb/c), considering the four models of SPSs and monoculture of parica and teak. The systems composed by teak are economically more attractive than that with paricá, and among all silv
Variabilidade entre procedências de paricá Schizolobium parahyba var amazonicum (Huber ex Ducke) Barneby plantadas no município de Colares - Pará
Ohashi, Selma Toyoko;Yared, Jorge Alberto Gazel;Farias Neto, Jo?o Tomé de;
Acta Amazonica , 2010, DOI: 10.1590/S0044-59672010000100011
Abstract: the study involved four three-year-old provenances of schizolobium parahyba var. amazonicum planted in the municipality of colares-pará, following an experimental design of randomized blocks with five replications. the studied characteristics were: survival, plant height, diameter at 1.30 m from the ground (dap), height and diameter of the tree crown, percentage of attacked plants and type of bark. differences among origins for the survival and growth in height of plant and dap had been found, however, no differences were found for crown height characteristics, crown diameter, percentage plants of attacked plants and bark type. the provenance with the highest survival was belterra. for plant growth in height and dap, the provenances belterra, ji-paraná and alta floresta were statistically similar, differing from brasiléia that presented the lowest development. the provenances belterra, alta floresta and ji-paraná can be recommended for reforestation programs and agroforestry systems for this region. the spearman correlation coefficient indicated a strong association among the production variables and the latitude, indicating that the provenances from lower latitudes tend to have a higher development. however, due to this study had involved only a small sample inside of the ample area of distribution of the species, it is advisable to extend the prospection and collecting activities for better explore the variability in the program of genetic improvement of the species.
Análise econ mica dos sistemas de cultivo com Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby (Paricá) E Ananas comosus var. erectifolius (L. B. Smith) Coppus & Leal (Curauá) no município de Aurora do Pará (pa), Brasil Economical analysis of cultivation systems with Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby (Parica) and Ananas comosus var. erectifolius (L. B. Smith) Coppus & Leal (Curaua) crop at Aurora do Pará, Brazil
Castro Coimbra Cordeiro,A Cordeiro de Santana,O.A Lameira,I Matos Silva
Revista de la Facultad de Agronomía , 2009,
Abstract: O objetivo do trabalho foi analisar a viabilidade econ mica dos sistemas de cultivo com Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby e Ananas comosus var. erectifolius (L. B. Smith) Coppus & Leal, considerando-se três sistemas distintos: I) Monocultivo de Paricá; II) Monocultivo de Curauá; e III) Sistema Paricá e Curauá. Os sistemas foram implantados no Campo Experimental da Empresa Tramontina Belém, localizado no município de Aurora do Pará (PA). A partir dos registros das contas de despesa e receita do or amento unitário, elaborados para cada sistema, foi construído o fluxo de caixa. A viabilidade econ mica foi determinada por meio do valor presente líquido (VPL), raz o benefício/custo (B/C) e taxa interna de retorno (TIR). Utilizou-se como custo de oportunidade uma taxa de juros de longo prazo de 12% ao ano. Os custos e as receitas foram mensurados em R$/ha. Os resultados mostraram que o monocultivo de Curauá apresentou o maior VPL (R$ 19.853,44), seguido do sistema agroflorestal de Paricá e Curauá (R$ 9.507,795). O sistema Paricá e Curauá apresentou a maior rela o benefício/custo (1,29) enquanto a menor ficou com o monocultivo de Paricá. Das atividades analisadas, o monocultivo de Curauá apresentou maior TIR (44%), seguido do sistema Paricá e Curauá (33%), valores superiores ao custo de oportunidade. A associa o Paricá e Curauá mostrou-se economicamente viável, tanto para agricultores que desejam implantar um povoamento florestal, quanto para as empresas madeireiras interessadas na redu o dos custos da implanta o de povoamentos florestais. The main purpose of this work was to analyze the economic viability of crop systems with Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby and Ananas comosus var. erectifolius (L. B. Smith) Coppus & Leal, considering three distinct systems: I) parica Monoculture; II) Curauá monoculture; and III) Paricá + Curauá system. The experiment was carried out in the Tramontina's Belém experimental field in Aurora do Pará, PA. From the registers of the accounts of expenditure and prescription of the unitary budget, elaborated for system each, a box flow was elaborated. The economic viability was determined through calculations of: Net Present Value (NPV), Benefit/cost ratio (B/C.R), Break-even point (BEP) and Internal Rate of Return (IRR) in three distinct activities. For tax calculations of a 12% of discounting was chosen. The costs and the prescriptions had been esteem in R$/ha. Results showed that Curauá monoculture had a greater VPL (R$ 19,853.44), followed by the plantation of parica a
Análise econ?mica dos sistemas de cultivo com Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby (Paricá) E Ananas comosus var. erectifolius (L. B. Smith) Coppus & Leal (Curauá) no município de Aurora do Pará (pa), Brasil
Castro Coimbra Cordeiro,; Cordeiro de Santana,A; Lameira,O.A; Matos Silva,I;
Revista de la Facultad de Agronomía , 2009,
Abstract: the main purpose of this work was to analyze the economic viability of crop systems with schizolobium parahyba var. amazonicum (huber ex ducke) barneby and ananas comosus var. erectifolius (l. b. smith) coppus & leal, considering three distinct systems: i) parica monoculture; ii) curauá monoculture; and iii) paricá + curauá system. the experiment was carried out in the tramontina's belém experimental field in aurora do pará, pa. from the registers of the accounts of expenditure and prescription of the unitary budget, elaborated for system each, a box flow was elaborated. the economic viability was determined through calculations of: net present value (npv), benefit/cost ratio (b/c.r), break-even point (bep) and internal rate of return (irr) in three distinct activities. for tax calculations of a 12% of discounting was chosen. the costs and the prescriptions had been esteem in r$/ha. results showed that curauá monoculture had a greater vpl (r$ 19,853.44), followed by the plantation of parica and curaua (r$ 9,507.795). the paricá and curauá system showed a high benefit/cost relation (1.29), while parica monoculture the b/c.r was less than 1. among the analyzed activities, the curauá monoculture showed a greater tir (44%) followed by the paricá and curauá system (33%). the association between paricá and curauá showed to be economically recommendable, as for agriculturists, whom they desire to implant a forest stand, as for companies interested in the reduction of the forest costs.
Cancro em Paricá (Schizolobium parahyba var. amazonicum) no Estado do Pará Canker Disease of Parica (Schizolobium parahyba var. amazonicum) in Para State, Brazil
Célia Regina Tremacoldi,Alexandre Mehl Lunz,Fábio Renato de Souza Costa
Pesquisa Florestal Brasileira , 2010, DOI: 10.4336/2012.pfb.59.69
Abstract: Plantios de paricá, avaliados no Município de Dom Eliseu, Estado do Pará, apresentaram sintomas de cancro. Várias espécies de fungos foram associadas ao cancro observado no campo, mais notavelmente Lasiodiplodia theobromae e Pestalotiopsis sp. Culturas isoladas destes fungos, frequentemente associados a outros (incluindo Fusarium oxysporum, Alternaria e basidiomicetes), foram testadas quanto à patogenicidade em plantas jovens de paricá, com aproximadamente um metro de altura. Apenas L. theobromae produziu cancro sob as condi es testadas, quando discos de cultura foram aplicados usando técnicas de inocula o por ferimento e alta umidade, reproduzindo perfeitamente os sintomas do campo. Pestalotiopsis sp. causou danos muito menores quando comparado a L. theobromae. A confirma o de L. theobromae como agente causal do cancro em paricá ocorreu após o reisolamento do fungo a partir dos tecidos sintomáticos das plantas inoculadas em casa-de-vegeta o, concluindo a verifica o dos Postulados de Koch. Este é o primeiro relato deste patógeno em paricá. Doi: 10.4336/2009.pfb.59.69 Canker have been found in field plantings of parica examined in Dom Eliseu county, Para State, Brazil. Several fungal species were associated with the field canker, most notably Lasiodiplodia theobromae and Pestalotiopsis sp. Isolated cultures of these fungi together with other often associated fungi (including Fusarium oxysporum, Alternaria, basidiomycetes) were tested for pathogenicity on young parica plants, with approximately one meter height. Only L. theobromae produced canker under the conditions tested when discs of culture were applied using wound inoculation techniques and high humidity, which closely mimicked the field symptoms. Pestalotiopsis sp. proved much less damaging compared to L. theobromae. The acknowledgment of L. theobromae as the causal agent of parica canker came after the reisolations of the fungus from symptomatic tissue of inoculated plants, concluding the verification of Koch’s Postulates. This is the first report of this pathogen in paricá.
NUTRIENT RIQUERIMENT OF Schizolobium amazonicum, Herb (PARICá) SEEDLINGS
Teresa Cristina Lara Lanza de Sá e Melo Marques,Janice Guedes de Carvalho,Mariluza Pinto Coelho Lacerda,Paulo Emílio Ferreira da Mota
CERNE , 2004,
Abstract: Macronutrients concentrations in leave, stem, and root tissues of Schizolobium amazonicum Herb. were determined under greenhouse conditions using the missing element technique. The experimental design was a completely randomized block with four replications and 13 treatments. Seedlings 0.05–0.10 -m high were planted into 3 L pots filled with nutritive solution. Based on the concentrations of macronutrients in the leaves of the complete and the deficient treatments, suitable and deficient levels (g kg-1) of macronutrients for S. amazonicum are: a) suitable: 4 for P; 15 for K; 40 for Ca; 4 for Mg; and 3 for S; 33of B; 5 of Cu; 540 of Fe, 88 of Mn; and 71 of Zn; b) critical: 1 for P; 4 for K; 8 for Ca; 1 for Mg; and 2 for S; 31 of B; 4 of Cu; 140 of Fe; 38 of Mn; and 24 of Zn
THE EFFECT OF BORON DOSES ON PARICA (Schizolobium amazonicum Herb.)
Sebasti?o Ferreira de Lima,Rodrigo Luz da Cunha,Janice Guedes de Carvalho,Carlos Alberto Spaggiari Souza
CERNE , 2003,
Abstract: An experiment was conducted in a greenhouse in order to evaluate the effects of boron on parica growth and on concentration and contents of macro and micronutrients indry matter of shoots and roots. Six treatments constituted by boron doses of 0.0; 0.1; 0.3; 0.9;1.5 and 2.1 mg/dm3 in four replications were used. It was evaluated the characteristics:visual diagnostic, plants height and diameter, dry matter production of shoots and roots,concentration and contents of nutrients in dry matter of shoots and roots. The symptoms ofdeficiency can be observed in new leaves and roots and the toxicity in older leaves. Bothboron deficiency and excess inhibits plants growth, but toxicity is more damaging. The Comportamento do paricá (Schizolobium amazonicum Herb.) submetido ...193approximate dose of 0 Estimate of average equilibrium moisture content of wood for 26Brazilian states, by Hailwood and Harrobin one hydrate sorption theory equation.15mg/dm3 was the best for plants growth in MSPA and MSRA. The concentration of boronincreased in MSPA and MSRA with application of increasing concentration of B, with a smallreduction in concentration of MSRA from the concentration 1.9 mg/dm3. The toxicity of boronbegins when concentration reaches 36.06 mg/dm3 in shoots and 32.38 in roots. The contentsof all nutrients, except Mn and Fe in MSPA and Cu, Fe and B in MSRA, followed its own drymatter production curves.
Scarification with sulphuric acid of Schizolobium amazonicum Huber ex Ducke seeds - FABACEAE
Cruz, Eniel David;Carvalho, José Edmar Urano de;Queiroz, Rafaela Josemara Barbosa;
Scientia Agricola , 2007, DOI: 10.1590/S0103-90162007000300017
Abstract: seed coat impermeability to water occurs in many species, including schizolobium amazonicum huber ex ducke. to promote germination in seeds with coat impermeability the use of sulphuric acid (h2so4) is recommended. the objective of this study was to identify a better time for the scarification with sulphuric acid for s. amazonicum seeds. the effect of scarification with sulphuric acid for 20, 40 and 60 min on germination and speed germination was studied for seeds that were either sowed immediately after scarification or after a 24-hour period of immersion in water. seeds were sown on a mix of sand and sawdust (1:1). the experimental design was completely randomized with four replications of 50 seeds. the statistical analysis of germination was carried out at six, nine, 12, 15, 18, 21 and 24 days after sowing, in a factorial scheme. for speed germination the means were compared by the tukey test. there was an interaction between treatments to overcome dormancy and immersion time after scarification in most evaluations. immersion in water accelerated the beginning of germination. all treatments to overcome dormancy promoted seed germination. however, scarification for 60 min, showed better germination, 92% when immediately sown and 86.5% when sown after 24 hours. speed germination index was highest for scarified seeds for 60 min followed by immersion in water. scarification for 60 min was the most efficient treatment to promote germination in s. amazonicum seeds.
Occurrence of Quesada gigas on Schizolobium amazonicum trees in Maranh?o and Pará States, Brazil
Zanuncio, José Cola;Pereira, Fabrício Fagundes;Zanuncio, Teresinha Vinha;Martinelli, Nilza Maria;Pinon, Tobias Baruc Moreira;Guimar?es, Edylene Marota;
Pesquisa Agropecuária Brasileira , 2004, DOI: 10.1590/S0100-204X2004000900015
Abstract: an infestation of quesada gigas olivier (hemiptera: cicadidae) on "paricá" schizolobium amazonicum (huber) ducken (fabales: fabaceae) was reported in the municipalities of itinga, maranh?o state and paragominas, pará state. nymphs of this insect on roots and adults and exuvias on trunks of the plant were observed. exit holes of nymphs in the soil were also observed. the occurrence of q. gigas on s. amazonicum shows the damage potential of this species and the necessity of developing integrated management programs for species of this group, specially in reforested areas with "paricá".
Modeling Growth and Yield of Schizolobium amazonicum under Different Spacings  [PDF]
Gilson Fernandes da Silva,Salvador Alejandro Gezan,Carlos Pedro Boechat Soares,Luciano Zumerle Zaneti
International Journal of Forestry Research , 2013, DOI: 10.1155/2013/675137
Abstract: This study aimed to present an approach to model the growth and yield of the species Schizolobium amazonicum (Paricá) based on a study of different spacings located in Pará, Brazil. Whole-stand models were employed, and two modeling strategies (Strategies A and B) were tested. Moreover, the following three scenarios were evaluated to assess the accuracy of the model in estimating total and commercial volumes at five years of age: complete absence of data (S1); available information about the variables basal area, site index, dominant height, and number of trees at two years of age (S2); and this information available at five years of age (S3). The results indicated that the 3 × 2 spacing has a higher mortality rate than normal, and, in general, greater spacing corresponds to larger diameter and average height and smaller basal area and volume per hectare. In estimating the total and commercial volumes for the three scenarios tested, Strategy B seems to be the most appropriate method to estimate the growth and yield of Paricá plantations in the study region, particularly because Strategy A showed a significant bias in its estimates. 1. Introduction In the past, logging of high-grade trees in Brazilian natural forests occurred in an unplanned and predatory way. At present, the trend is toward increasingly rigorous environmental legislation to prevent illegal harvesting of natural forests. In Brazil, most wood still comes from native forests. Companies that produce pulpwood and fuelwood constitute a minor part of the total timber production and often fill their needs with their own supply. In contrast, companies that produce sawtimber and plywood correspond to a large proportion of the total production and usually require wood from native forests. The increasing difficulty removing wood from native forests due to legislation or supply has resulted in some companies beginning to produce high economic value species through commercial plantations. However, little is often known about the silviculture of some of these native species, and it is typically difficult to find improved genetic material for high yields and more homogeneous forests. One attractive native species that has been planted in recent years due to its favorable characteristics is Schizolobium amazonicum Huber ex Ducke, known in Brazil as Paricá. This species has rapid growth, a straight bole, natural pruning, and highly valued wood in domestic and foreign markets [1, 2]. Paricá has been widely cultivated by timber companies in the northern and northeastern regions of Brazil, mainly in the
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.