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Wild and commercial mushrooms as source of nutrients and nutraceuticals

Barros, Lillian; Cruz, Telma; Baptista, Paula; Estevinho, Leticia M.; Ferreira, Isabel C.F.R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.6%
In order to promote the use of mushrooms as source of nutrients and nutraceuticals, several experiments were performed in wild and commercial species. The analysis of nutrients included determination of proteins, fats, ash, and carbohydrates, particularly sugars by HPLC-RI. The analysis of nutraceuticals included determination of fatty acids by GC-FID, and other phytochemicals such as tocopherols, by HPLC-fluorescence, and phenolics, flavonoids, carotenoids and ascorbic acid, by spectrophotometer techniques. The antimicrobial properties of the mushrooms were also screened against fungi, Gram positive and Gram negative bacteria. The wild mushroom species proved to be less energetic than the commercial sp., containing higher contents of protein and lower fat concentrations. In general, commercial species seem to have higher concentrations of sugars, while wild sp. contained lower values of MUFA but also higher contents of PUFA. ?-Tocopherol was detected in higher amounts in the wild species, while ?-tocopherol was not found in these species. Wild mushrooms revealed a higher content of phenols but a lower content of ascorbic acid, than commercial mushrooms. There were no differences between the antimicrobial properties of wild and commercial species. The ongoing research will lead to a new generation of foods...

Carbon and nutrients stocks in even-aged maritime pine stands from Portugal

Nunes, Luís; Patrício, Maria do Sameiro; Tomé, José; Tomé, Margarida
Fonte: Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA) Publicador: Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA)
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.74%
To comply with the demands of the Kyoto Protocol, industrialized countries must reliably estimate the stored carbon (C) in different pools of forest ecosystems. The main objective of this study was to quantify the biomass, C and nutrients stocks in the forest floor, understory, downed dead wood (DDW) and mineral soil of even-aged maritime pine (Pinus pinaster Ait.) stands from three contrasting regions of Portugal. Assessing the specific contribution of DDW to the C and nutrients stocks and how C concentration in the plant material differs from 0.50, the reference value used in many practical applications, were also objectives of this research. Biomass content of forest floor was determined by a quadrat method. Sampling units of 1 m2 were used for the understory. The line intersection method was adopted for sampling DDW and the mineral soil was sampled at three depths. Concentrations of C and nutrients were obtained by chemical analysis of samples from soil and milled plant material. Biomass and C in the trees were obtained using published equations. Total C stocks ranged between 100.6 Mg ha–1 and 308.6 Mg ha–1. Mineral soil shared up to 70-74% of global stored C, being the main cause of the global C stock differences among regions. Phosphorous and potassium were at low to very low levels in the mineral soil and plant material. The contribution of DDW to the C and nutrients pools was negligible. The percentage of C in the plant material ranged between 52% and 54%.

Fertiliser recommendations for olive based upon nutrients removed in crop and pruning

Rodrigues, M.A.; Ferreira, I.Q.; Claro, Ana Marília; Arrobas, Margarida
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.84%
The above-ground part of fourteen, young (ten-year-old), rainfed olive trees were separated into trunk (wood and bark), main branches (wood and bark), secondary branches (wood and bark), twigs, leaves and fruits. Based on the dry matter and nutrient concentration in the different tissues, the total amounts of nutrients in each tree were estimated. A controlled scheme of pruning conducted annually allowed the quantification of the amount of nutrients removed in pruning. Olive yields and nutrient concentrations in the fruits (pulp and pit) were used to quantify the nutrients removed in the crop. The results showed that the amounts of nutrients annually removed were relatively low, suggesting that more conservative fertilizer applications could be made than those usually recommended by the laboratories of soil testing and plant analysis. In this orchard, with a yield goal of 2500 kg fruit ha?1, the nitrogen (N) rate to apply as fertilizer should not exceed 20 kg N ha?1 year?1. The transient nature of N in the soil/plant systems recommends that N be applied every year to increase the nutrient-use efficiency. The application of other nutrients as fertilizer should be diagnosed beforehand by soil testing and/or plant analysis. Nutrients removed by crop and pruning do not provide all the information on the need for supplemental fertilizer applications. Soil testing and plant analysis should be used routinely for a continuous adjustment of the fertilizer program.

EVALUATION OF THE INTERACTION OF NUTRIENTS IN THE ZINC APPLICATION IN SEEDS OF THE RICE

SOUZA, Henrique Antunes de; ROZANE, Danilo Eduardo; PRADO, Renato de Mello; ROMUALDO, Liliane Maria
Fonte: UNIV FEDERAL UBERLANDIA Publicador: UNIV FEDERAL UBERLANDIA
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.68%
The efficient fertilizer use contend micronutrient depends, also, of the interactions that occur with some nutrients. The objective was to study the interaction of zinc with the excessively nutrient ones in function of the application of different doses and sources of Zn saw seed in the culture of the rice. The experiment was carried through in conditions of vegetation house, in the FCAV/Unesp. The used experimental delineation was entirely cazualized, with three repetitions. The treatments had been five doses: 0; 1,0; 2,0; 4,0 and 8,0 g of Zn for kg of seed; e two zinc sources; sulphate of zinc (22% of Zn) and zinc oxide (50% of Zn). The experimental unit was a translucent polyethylene tray, filled with 5 washed thick sand, where 50 seeds of rice had been sown (to var. Caiapo). To the 30 days after the sowing, effected the cut of the plants, separating them in aerial part and roots. From the results of the dry substance and text of nutrients of the aerial part and root of the rice, the accumulation of the nutrients in the respective agencies of the plants was calculated. Becoming fullfilled it variance analysis and the when necessary unfoldings. It had effect of the interactions in distinguishing way between root and aerial part of rice...

Produção de colmos e exportação de macronutrientes primários por cultivares de cana-de-açúcar (Saccharum spp.).; Yield of stalks and exportation of major nutrients by sugarcane (saccharum spp.) varieties.

Gomes, Jorge Fernando Favaro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 16/04/2003 Português
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36.68%
A vinhaça é um resíduo que pode representar um problema ambiental, porém pode ser utilizado com fertilizante potássico na cultura da cana-de-açúcar, que apresenta uma grande importância na agricultura brasileira. A seleção de cultivares com um comportamento adequado às áreas que receberam esse resíduo, e o conhecimento das quantidades exportadas de macronutrientes primários pelos colmos, tem importância na melhoria da produtividade agrícola. Doze cultivares de cana-de-açúcar foram cultivadas em um LATOSSOLO VERMELHO-AMARELO Distrófico psamítico (LVA) e um NITOSSOLO VERMELHO Eutroférrico latossólico (NV), no município de Rafard, SP, em áreas com aplicação de vinhaça, durante três safras. As cultivares, em função das características genéticas, do ano agrícola, do estágio e do conjunto de práticas utilizadas, apresentaram diferenças de produção, dentro de cada solo. A cultivar RB 835089 apresentou uma boa adaptação, enquanto que as cultivares RB 72454, SP 80-1842 apresentaram desempenho intermediário, nos dois ambientes. Já as cultivares RB 835486, RB 845257 e RB 825336 adaptaram-se melhor ao LVA e as cultivares SP 80-3280 e RB 855536 ao NV. As cultivares apresentaram concentrações diferentes de nutrientes em função do solo...

Ciclagem de nutrientes após aplicação de lodo de esgoto (Biossólido) sobre latossolo cultivado com Eucalyptus grandis; Nutrients cycling after sewage sludge (biosolid) apllication on oxisol planted with Eucalyptus Grandis

Guedes, Marcelino Carneiro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 08/03/2005 Português
Relevância na Pesquisa
36.78%
O tratamento das águas residuárias gera um resíduo, o lodo de esgoto, que poderia ser utilizado para aumentar a produtividade de culturas agrícolas e florestais. O objetivo geral deste trabalho foi estudar como a utilização do biossólido em um povoamento de Eucalyptus grandis afeta a ciclagem biogeoquímica de nutrientes. O estudo foi desenvolvido na Estação Experimental de Itatinga, vinculada ao Departamento de Ciências Florestais da ESALQ/USP. O experimento foi instalado em março de 1998 em um delineamento em blocos casualizados, com cinco tratamentos (testemunha, adubação mineral, 10 Mg ha-1 de biossólido + KP, 20 Mg ha-1 de biossólido + K e 40 Mg ha-1 de biossólido + K). Os resultados mostraram que a aplicação de biossólido alterou o desenvolvimento e o estado nutricional dos eucaliptos, bem como os padrões de reciclagem dos nutrientes. A produção de fitomassa arbórea pelos eucaliptos que receberam 10 Mg ha-1 de biossólido + K e P mineral foi significativamente maior do que no tratamento testemunha e, em média, maior também do que na fertilização mineral. Com as doses de biossólido, também foi verificado um significativo aumento na produção de serapilheira e na devolução de nutrientes ao solo. Durante quatro anos de desenvolvimento...

Avaliação do histórico de impactos antrópicos na bacia de drenagem do Lago das Garças (São Paulo-SP), durante o século XX, com base nos estoques de nutrientes, metais pesados e compostos orgânicos em sedimento lacustre; Evaluation of human impact at Garças lake drainage basin (São Paulo, SP) during the 20th Century based in nutrients, heavy metals and organic compounds in lacustrine sediments

Jesus, Tatiane Araujo de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 07/11/2008 Português
Relevância na Pesquisa
36.6%
O presente estudo visou reconstruir o histórico de impactos antrópicos na bacia de drenagem do Lago das Garças durante o século XX por meio da deposição de contaminantes no compartimento sedimentar. O Lago das Garças está localizado em uma unidade de conservação, Parque Estadual das Fontes do Ipiranga (PEFI), inserida em área altamente povoada e urbanizada da cidade de São Paulo. Dois testemunhos de sedimento (LG05-03 e LG05-04, com 70 cm e 65 cm, respectivamente) foram amostrados mediante auxílio de mergulhadores no ponto mais profundo do reservatório, sendo, posteriormente, fatiados a cada 1 cm. Em LG05-03 foram quantificadas as distribuições verticais de carbono orgânico total (COT), nutrientes totais (NT e PT), hidrocarbonetos policíclicos aromáticos (HPA), hidrocarbonetos alifáticos (n-alcanos), bem como foi feita a classificação granulométrica. Em LG05-04 foi determinada a deposição de metais pesados (Co, Cr, Cu, Fe, Mn, Ni, Pb e Zn) e a geocronologia através do isótopo radioativo 'ANTPOT. 210 Pb', usando o modelo CIC (Constant Initial Concentration). Os dados foram analisados por meio de análises estatísticas multivariadas (ACP: Análise de Componentes Principais). Com base nas tendências dos dados e na ACP...

Estudo do balanço biogeoquímico dos nutrientes dissolvidos principais como indicador da influência antrópica em sistemas estuarinos do Nordeste e Sudeste do Brasil; Study of biogechemical ratios of dissolved nutrients as indicator of the anthropogenic influence in Northeastern and Southeastern estuarine systems of Brazil

Eschrique, Samara Aranha
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 10/10/2011 Português
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36.68%
Este trabalho teve como proposta principal avaliar os efeitos de ações antrópicas sobre sistemas estuarinos com base no balanço biogeoquímico entre as formas de nutrientes (N, P e Si). Foram estudados dois sistemas estuarinos localizados em pontos extremos da costa, um no nordeste, o estuário do Rio Jaguaribe, no Ceará, e outro no sudeste, o complexo estuarino-lagunar de Cananéia e Iguape, em São Paulo. Estes sistemas estão sob os diferentes regimes climáticos e o estudo envolveu: aspectos dos períodos de seca e chuva nos dois locais; o efeito da maré; e, o aporte de águas doces quer sob a forma de chuva, quer via drenagem continental e barragens. A influência antrópica mostrou a ação sobre o excesso de silício nos dois sistemas. O fósforo foi o elemento dissolvido que recebeu maior ação neutralizadora, sendo "tamponado" de forma que não ofereceu sinais de eutrofização. Este não é o caso das formas nitrogenadas, que mostraram uma assinatura relativa às atividades antrópicas que mais impactam cada região. No caso do Rio Jaguaribe, o aporte de matéria orgânica e de nutrientes via atividade de carcinicultura colaborou ao destaque na forma de N-amoniacal nas águas do médio e baixo estuário, onde se localizam as fazendas de carcinicultura. Os sinais mais acima no sistema estiveram ligados aos aportes via barragem e da cidade de Aracati. No caso do complexo estuarino-lagunar de Cananéia e Iguape...

Estado nutricional e disponibilidade de nutrientes e carotenóides para a população brasileira; Nutritional status and availability of nutrients and carotenoids for the Brazilian population

Gaino, Natalia Moreno
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 18/05/2012 Português
Relevância na Pesquisa
36.74%
O trabalho teve por objetivo analisar a disponibilidade domiciliar de energia, nutrientes e carotenóides para as famílias brasileiras residentes nas áreas rurais e urbanas, das Grandes Regiões Geográficas, bem como o estado nutricional dos indivíduos adultos pertencentes a esta população. Utilizou-se como base de dados as informações individuais obtidas por meio da Pesquisa de Orçamentos Familiares (POF 2008-2009) do Instituto Brasileiro de Geografia e Estatística (IBGE). Adotou-se preliminarmente um banco de dados criado a partir dos microdados da POF 2002- 2003. Essa planilha revisada e atualizada gerou um novo banco de dados. Utilizouse como parâmetro para a avaliação da participação de macronutrientes no Valor Energético Total (VET) e disponibilidade de vitaminas e minerais os valores preconizados pelo Institute of Medicine (1997, 1998, 2000, 2001, 2002, 2004). Para a identificação do conteúdo de carotenóides foram adotadas as informações contidas na tabela Nutrient Database for Standard Reference Release 23 - United States of Department Agriculture (USDA). A disponibilidade média diária de energia e nutrientes e estado nutricional foram calculados utilizando o programa Statistical Analysis System SAS. Os resultados evidenciam diferenças da disponibilidade de energia e nutrientes para as famílias brasileiras...

Crescimento e marcha de absorção de nutrientes de crisântemo (Dendranthema grandiflora, Tzvelev.) cultivado em vaso; Growth and nutrients uptake curve of chrysanthemum (Dendranthema grandiflora, Tzvelev.) cultivated in pot

Rodrigues, Marcelo Antonio
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 07/11/2013 Português
Relevância na Pesquisa
36.6%
O crisântemo cultivado em vaso é um dos produtos floríferos mais vendidos na floricultura brasileira, possuindo grande diversidade de cores, formas e tamanhos de inflorescências, além de possuir alta durabilidade após a colheita. Para tanto, é necessário o atendimento das exigências nutricionais da planta para possibilitar expressar seu potencial ornamental. Os objetivos deste trabalho foram analisar o crescimento da planta e caracterizar a marcha de absorção de nutrientes no cultivo em vaso do crisântemo, variedade cultivada ,,Fine Time". O experimento foi realizado na estufa climatizada do Setor de Floricultura do Colégio Politécnico da UFSM, Santa Maria - RS, no período de setembro a dezembro de 2012. O delineamento experimental foi inteiramente casualizado com oito tratamentos e seis repetições. As plantas foram coletadas e analisadas em intervalos que variaram de 7 a 14 dias dependendo da fase de desenvolvimento da planta. Os parâmetros de crescimento avaliados foram: comprimento das hastes, folhas e de raízes; número de folhas, raízes, brotações, botões florais e de inflorescências; largura e área das folhas; massa de matéria seca das folhas, raízes; botões florais; inflorescências, hastes e das plantas. Em relação aos nutrientes foi analisado teor...

Determinação de nutrientes e contaminantes Inorgânicos em café solúvel por espectrometria de emissão atômica com plasma de argônio induzido (ICP-AES); Determination of nutrients and inorganic contaminants in soluble coffee by atomic emission spectrometry with inductively-coupled plasma (ICP-AES)

Santos, Eder José dos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 07/04/1999 Português
Relevância na Pesquisa
36.68%
A produção industrial do café solúvel brasileiro destina-se, na sua maior parte, ao mercado externo, constituindo-se em um importante ítem de exportação do país. O objetivo do presente trabalho foi o desenvolvimento e aprimoramento de métodos de análise química adequados à investigação de componentes inorgânicos em café solúvel. Inicialmente foi definido o método de mineralização das amostras através da avaliação de 6 procedimentos diferentes, classificados em 3 classes: (I) microondas focalizado; (II) via úmida convencional e (III) sistema sob pressão em frascos de decomposição com tampas (bombas de teflon). As determinações dos nutrientes e contaminantes inorgânicos: Na, K, Mg, Al, P, S, Ca, Mn, Fe, Ni, Cu, Zn, Cd, Sb, Pb, Cr, Sn, As, Se e Hg, após a utilização do procedimento de mineralização que emprega o sistema de microondas focalizado com os reagentes HNO3 e H2O2, foram realizadas por espectrometria de emissão atômica com plasma induzido, ICP-AES (da nomenclatura inglesa Inductively Coupled Plasma-Atomic Emission Spectrometry). Interferências de matriz e/ou espectrais foram detectadas nas determinações de Pb, Cr, Sn, As, Se e Hg. No caso do Sn, optou-se pela correção da radiação de fundo através do software do equipamento...

Peat humic substances enriched with nutrients for agricultural applications: Competition between nutrients and non-essential metals present in tropical soils

Botero, Wander Gustavo; de Oliveira, Luciana Camargo; Rocha, Julio Cesar; Rosa, Andre Henrique; dos Santos, Ademir
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: info:eu-repo/semantics/conferenceobject Formato: 307-311
Português
Relevância na Pesquisa
36.68%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Improved agricultural productivity, and reduction of environmental impacts, require studies of the interactions between different soil components. Fertilizers marketed as "organic" or "natural", such as peats or humic substances (HS) extracted from peats, are enriched with macro and micronutrients that, according to the manufacturers, are released to the plant in accordance with its needs. This work investigates the complexation capacity of HS for macro and micronutrient metal species, considering the competition, for HS complexation sites, between non-essential metals (aluminium and lead), present in the soil, and the nutrients. Humic substances were found to possess strong affinities for Pb(II) and Al(III), forming stable complexes, with concomitant release of complexed nutrients. Although HS are already used commercially as organic fertilizers, further studies of methods of HS enrichment, aimed at avoiding losses, are highly desirable from environmental and economic perspectives. (C) 2009 Elsevier B.V. All rights reserved.

Nutrient cycling aspects in stands of Pinus-elliottii engelm var elliottii under differents resining intensities .2. nutrients contents in litter

Soave, RDF; Pagano, S. N.
Fonte: Inst Tecnologia Parana Publicador: Inst Tecnologia Parana
Tipo: Artigo de Revista Científica Formato: 711-721
Português
Relevância na Pesquisa
36.6%
Annual and monthly quantities of nutrients wich returned to the soil through litter fall in Pinus elliottii Engelm. var. elliottii stand were estimated durint a two years period, in Experimental Station of Mogi-Guacu, SP. From the trees of the stand was extracted oleoresin according two differents techniques and control. The annual average of nutrients that returned to the soil was 72.2 Kg/ha, in following order: N > Ca > K > Mg > P. No relationship appeared between nutrient concentrations plus quantities when they were compared with oleoresin yields treatments and control. The differences in annual quantities were possibly due to climatic factors. The soil profile showed short concentrations in nutrient contents. Thus, the forest may be suffering by nutrient deficiences.

Peat humic substances enriched with nutrients for agricultural applications: competion between nutrients and non-essential metals present in tropical soils

Botero, Wander Gustavo; Oliveira, Luciana Camargo de; Rocha, Julio Cesar; Rosa, André Henrique; Santos, Ademir dos
Tipo: Artigo de Revista Científica Formato: 307-311
Português
Relevância na Pesquisa
36.68%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Improved agricultural productivity, and reduction of environmental impacts, require studies of the interactions between different soil components. Fertilizers marketed as “organic” or “natural”, such as peats or humic substances (HS) extracted from peats, are enriched with macro and micronutrients that, according to the manufacturers, are released to the plant in accordance with its needs. This work investigates the complexation capacity of HS for macro and micronutrient metal species, considering the competition, for HS complexation sites, between non-essential metals (aluminium and lead), present in the soil, and the nutrients. Humic substances were found to possess strong affinities for Pb(II) and Al(III), forming stable complexes, with concomitant release of complexed nutrients. Although HS are already used commercially as organic fertilizers, further studies of methods of HS enrichment, aimed at avoiding losses, are highly desirable from environmental and economic perspectives.

Annual dynamics of nutrients in a temporary stream in Southern Portugal: contributions of the primary producers and the drainage basin

Pedro, Ana; Morais, Manuela; Rosado, Joana
Fonte: TEMPRIV2012 International Conference on Temporay Rivers Publicador: TEMPRIV2012 International Conference on Temporay Rivers
Tipo: lecture
Português
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36.74%
Under the Mediterranean climatic conditions, the annual precipitation distribution determines that many streams are temporary with surface flow interruption during the summer dry period in contrast to the high discharges during floods, observed from late autumn to early spring. As water flows through the drainage basin it can pick up nutrients, sediments and pollutions. These can affect the ecological processes causing eutrophication where primary producers’ growth is accelerated. In this study, the nutrient (N and P) concentrations were determined in water and river sediments, over a 3 years period in a 3rd order temporary stream reach of 500 m (Pardiela stream in Guadiana basin). The nutrients concentration in the water and in the sediment shows a decrease during the flood events due to the high discharge, followed by a rapid increase, although the nutrients concentrations in the sediments were smaller than in the water. The primary producers were studied during the same 3 years period, in terms of biomass of macrophytes, periphyton, and leaves fall in order to describe the annual patters. Complementary, a rapid assessment of N, P and C concentration in macrophytes was analyzed with the objective to determine their nutrients contribution to the system in summer (1047.35 g/m2) although with low contents of P...

Release of Nutrients and Organic Matter from River Floodplain Habitats: Simulating Seasonal Inundation Dynamics

Ostoji?, Ana; Rosado, J.; Miliša, M.; Morais, M; Tockner, K.
Fonte: SWS Publicador: SWS
Tipo: Artigo de Revista Científica
Português
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36.6%
River floodplains form a complex mosaic of aquatic, semi-aquatic, and terrestrial habitats. While spatially distinct, these habitats are connected through water, carbon and nutrients, and thus ecosystem processes in one habitat type may have ramifications for others. In the laboratory, we studied the effects of inundation duration (12, 36 and 96 h)and water temperature (4, 12 and 25 °C) on the release of nutrients and organic carbon from sediments of seven habitat types, and from leaves (Populus nigra L.), from the nearnatural,braided, Tagliamento River in NE Italy. The relative content of POC, TN, and TP was similar in the sediment size fraction

Carbon and nutrients stocks in even-aged maritime pine stands from Portugal

Nunes, L.; Patricio, M.; Tomé, J.; Tomé, Margarida
Fonte: INIA Publicador: INIA
Tipo: Artigo de Revista Científica
Publicado em //2010 Português
Relevância na Pesquisa
36.74%
To comply with the demands of the Kyoto Protocol, industrialized countries must reliably estimate the stored carbon (C) in different pools of forest ecosystems. The main objective of this study was to quantify the biomass, C and nutrients stocks in the forest floor, understory, downed dead wood (DDW) and mineral soil of even-aged maritime pine (Pinus pinaster Ait.) stands from three contrasting regions of Portugal. Assessing the specific contribution of DDW to the C and nutrients stocks and how C concentration in the plant material differs from 0.50, the reference value used in many practical applications, were also objectives of this research. Biomass content of forest floor was determined by a quadrat method. Sampling units of 1 m2 were used for the understory. The line intersection method was adopted for sampling DDW and the mineral soil was sampled at three depths. Concentrations of C and nutrients were obtained by chemical analysis of samples from soil and milled plant material. Biomass and C in the trees were obtained using published equations. Total C stocks ranged between 100.6 Mg ha–1 and 308.6 Mg ha–1. Mineral soil shared up to 70-74% of global stored C, being the main cause of the global C stock differences among regions. Phosphorous and potassium were at low to very low levels in the mineral soil and plant material. The contribution of DDW to the C and nutrients pools was negligible. The percentage of C in the plant material ranged between 52% and 54%.

Use of fractional factorial design for selection of nutrients for culturing Paecilomyces variotii in eucalyptus hemicellulosic hydrolysate

Almeida e Silva,J.B.; Lima,U.A.; Taqueda,M.E.S.; Guaragna,F.G.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/1998 Português
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36.6%
A eucalyptus hemicellulose fraction was hydrolysed by treating eucalyptus wood chips with sulfuric acid. The hydrolysate was used as the substrate to grow Paecilomyces variotii IOC-3764 cultured for 72 or 96 hours. The influence of the inhibitors, nutrients and fermentation time was verified by a 28-4 and, subsequently, a 25-1 fractional factorial design. The effects of the inhibitors (acetic acid and furfural), nutrients (rice bran, urea, potassium nitrate, ammonium sulfate, magnesium sulfate and sodium phosphate) and fermentation time were investigated. The highest yield (10.59 g/L of biomass) was obtained when the microorganisms were cultivated for 72 hours in a medium composed of 30 g/L rice bran, 9.4 g/L ammonium sulfate (2 g/L nitrogen) and 2 g/L sodium phosphate.

Effects of the application of sewage sludge and petrochemical residue in maize culture as source of micro-nutrients on soils of Paraná state

Pigozzo,Ana T. Jordão; Gobbi,Marlene A.; Lenzi,Ervim; Luchese,Eduardo B.
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2000 Português
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An evaluation of the potential of two organic residues as source of micro-nutrients in three soils of Paraná state was studied. Treatments consisted of one dose (38 t.ha-1) of sewage sludge and residue of purified used motor oil both neutralized with CaO+MgO mixture in 3:1 rate. Maize (Zea mays L.) was used as reference plant. After 30 days of seeding, the aerial parts of the plants were cut. They were dried at 70ºC till constant weight and ground. Analysis was undertaken after nitric-perchloric digestion. Micro-nutrients levels in the soils and in the aerial parts of the plants were determined by atomic absorption spectrometry. The results showed a production of the aerial parts of the plants treated with sewage sludge higher than those in other treatments. The micro-nutrients in Terra Roxa - TR were higher than those of Latossolo Vervelho Escuro - LE (Deep Red Latisol) and Podzólico Vermelho - PV (Red Podzolic) soils, respectively. In the aerial part of the maize plants in treated soils concentrations of micro-nutrients Cu, Fe, Mn and Zn were higher than those without treatment.

White Vegetables: A Forgotten Source of Nutrients: Purdue Roundtable Executive Summary12

Weaver, Connie; Marr, Elizabeth T.
Fonte: American Society for Nutrition Publicador: American Society for Nutrition
Tipo: text
Publicado em 06/05/2013 Português
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Purdue University convened a scientific roundtable, “White Vegetables: A Forgotten Source of Nutrients,” in Chicago, IL, June 18–19, 2012, to bring together experts to address the contributions of white vegetables, including potatoes, as sources of key nutrients and other microconstituents within a dietary pattern supporting health and wellness. This paper summarizes the meeting and supplement papers, including discussion among participants. The group of researchers identified areas of ambiguity regarding classification of vegetables for research and dietary guidance, future research needs, and the imperative to draw on that research to enhance evidence-based dietary guidance about white vegetables, including potatoes. U.S. dietary guidance encourages consumption of a variety of fruits and vegetables, including at least 1 serving of a dark green and 1 orange vegetable daily. However, no such recommendation exists for white vegetables, such as potatoes, cauliflowers, turnips, onions, parsnips, mushrooms, corn, and kohlrabi. Vegetable subgrouping approaches need to be considered in the context of nutrients of concern and low fruits and vegetable consumption. This Roundtable and supplement provide a substantial body of evidence to demonstrate how the inclusion of white vegetables...