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Prediction of soil chemical attributes using optical remote sensing; Predição de atributos químicos do solo utilizando sensoriamento remoto ótico

GENÚ, Aline Marques; DEMATTÊ, José Alexandre Melo
Fonte: Editora da Universidade Estadual de Maringá - EDUEM Publicador: Editora da Universidade Estadual de Maringá - EDUEM
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
55.88%
Soil fertility variability management is one of the pioneering and important areas in which Precision Agriculture has been commercially applied. Consequently, the objective of this work was to predict soil chemical attributes through spectral responses. The 1,000 ha study area used for this report was located in Uberlândia, MG, Brazil. Thirty sampling points were established, at which the soil was collected at 3 different depths. The samples were chemically and physically analyzed and the radiometric data obtained in the 400 - 2500 nm range. Multiple regression equations were generated for sum of bases, cation exchange capacity, base saturation, aluminum saturation, pH, P, K, Ca, Mg, Al, and H, all using 60 soil samples. H, Al, m%, and pH were found to have R² values less than 0.50. Equations with an R² > 0.50 for the other attributes were tested for the 30 unknown soil samples, and the estimated values were obtained. These values were then compared with those determined by conventional analysis. The coefficients of correlation were higher than 50% for all attributes except P and V%. Results indicated that determining chemical attributes with models that are specific for the region is feasible.; Uma das primeiras e mais importantes áreas nas quais a Agricultura de Precisão está sendo comercialmente aplicada é o manejo da variabilidade da fertilidade do solo. Desta forma...

Sensoriamento remoto e sistema de informações geográficas na caracterização de solos e quantificação de seus atributos; Remote sensing and geographic information system for soil characterization and quantification of it attributes

Sousa Junior, José Geraldo de Abreu
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 27/01/2006 PT
Relevância na Pesquisa
55.93%
Com a crescente adoção da agricultura de precisão, há uma busca por informações mais detalhadas da variabilidade espacial dos solos em escalas que viabilizem um manejo diferenciado da área de produção. Entretanto, o custo das análises de solo é sem dúvida um dos principais entraves para obtenção dessas informações. A adoção do geoprocessamento, utilizando-se o sensoriamento remoto, GPS e sistemas de informações geográficas para caracterização de solos e quantificação de seus atributos, é um desafio que vem sendo buscado por vários pesquisadores por ser uma tecnologia alternativa de avaliação do solo, podendo ser mais barata, rápida e com menor impacto ambiental. Contudo, como qualquer tecnologia de ponta, ela deve ser devidamente testada e ajustada para os mais diversos tipos de solos e regiões. Para tanto, foram escolhidas áreas localizadas na região de São Carlos e Ibaté, São Paulo, tendo os seguintes objetivos: (i) caracterizar o comportamento espectral de solos por sensores terrestre (FieldSpec) e orbital (ASTER); (ii) determinar alterações no comportamento espectral dos solos ao longo de diferentes toposseqüências; (iii) gerar modelos de quantificação de atributos químicos e granulométricos dos solos a partir de sua radiação eletromagnética e (iv) caracterizar os solos da região conforme a altitude e declividade do terreno utilizando-se técnicas de sistema de informações geográficas. Para isso foram coletadas amostras no campo e realizado o mapeamento da área. As amostras foram avaliadas por diferentes sensores e correlacionou-se seus atributos com a reflectância. Desta forma...

Análise físico-química de amostras de méis de Apis mellifera e Meliponíneos; Physico-chemical analysis of honey samples of Apis mellifera and Meliponid

Pereira, Luzimario Lima
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 05/11/2010 PT
Relevância na Pesquisa
55.73%
O mel de abelhas é um produto biológico muito complexo, cuja composição varia notavelmente em função da flora visitada pelas abelhas e das condições climáticas e edáficas da região onde foi produzido. Este trabalho teve como objetivos confrontar os resultados das análises físico-químicas entre as amostras de méis produzidos em diferentes localidades do Brasil por Apis mellifera e por Meliponíneos e investigar se o mel produzido por essas abelhas nas suas diferentes regiões de origem apresenta níveis toleráveis de contaminantes inorgânicos. Para tanto, foram avaliadas 56 amostras de méis de A. mellifera e 56 amostras de méis de Meliponíneos dos Estados da Bahia, Minas Gerais, Mato Grosso do Sul, Paraíba, Piauí, Paraná, Santa Catarina e São Paulo, em relação aos seguintes parâmetros: umidade, atividade de água, viscosidade, pH, acidez livre, índice de formol, açúcares redutores, sacarose aparente, teor de cinzas, cor, condutividade elétrica, hidroximetilfurfural, atividade diastásica e metais (Hg+2, Zn+2, Cd+2, Pb+2 e Cu+2). Foi utilizada a técnica de Voltametria de Redissolução Anódica de Pulso Diferencial (DPASV) para quantificar os metais, e métodos convencionais e próprios para mel nas demais análises. Os resultados mostraram que a legislação atual...

Influence of organic-mineral fertilization of an oxisol on soil chemical properties and Bracharia brizantha production

Schiavoni, Edmar Andrade; Alves, Marlene Cristina; Souza, Zigomar Menezes de; Costa, Frederick Gonçalves
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: 2219-2226
ENG
Relevância na Pesquisa
55.95%
A utilização de fertilizante organomineral da indústria produtora dos aminoácidos lisina e treonina pode melhorar a fertilidade de solos tropicais. O presente trabalho teve como objetivo avaliar a influência de diferentes dosagens do fertilizante organomineral denominado Ajifer L-14 nos atributos químicos e no aumento de produção de forragem de um Latossolo Vermelho do noroeste paulista. O delineamento utilizado foi em blocos casualizados, com sete tratamentos e quatro repetições. Os tratamentos foram: T1- testemunha (sem aplicação de Ajifer L-14); T2- testemunha com vegetação natural; T3- adubação mineral de acordo com a necessidade da cultura e a análise do solo (usando 1,35 kg de ureia, 2,20 kg de superfosfato simples e 0,51 kg de KCl por parcela, o que corresponde a 60 kg de N, 40 kg de P2O5 e 30 kg ha-1 de K2O, respectivamente); T4- adubação com Ajifer L-14 de acordo com a recomendação da análise química do solo (40 L parcela-1, o que corresponde a 60 kg ha-1 N); T5- adubação com Ajifer L-14 em dosagem 50 % acima da recomendação (60 L parcela-1, o que corresponde a 90 kg ha-1 N; T6- adubação com Ajifer L-14 em dosagem 50 % abaixo da recomendação (20 L parcela-1, o que corresponde a 30 kg ha-1 N); T7- adubação com Ajifer L-14 em dosagem 25 % acima da recomendação (50 L parcela-1...

Influência da secagem, armazenamento e embalagem nos resultados da análise química de terra para fins de fertilidade

Chitolina, J.C.; Glória, N.A.da; Boaretto, A.E.; Curi, P.R.
Fonte: Universidade de São Paulo (USP), Escola Superior de Agricultura Publicador: Universidade de São Paulo (USP), Escola Superior de Agricultura
Tipo: Artigo de Revista Científica Formato: 343-359
POR
Relevância na Pesquisa
55.87%
Amostras de terra provenientes de uma Terra Roxa Estruturada e um Latossol Vermelho Escuro textura média foram analisados quimicamente para se verificar a influência de embalagem (caixa de papelão saco de polietileno), tempo de armazenamento (1-32 dias) e processo de secagem (ao ar ou estufa a 60°C). A secagem foi o fator que mais influenciou a análise determinando variações nos resultados analíticos principalmente para pH e fósforo. O armazenamento apresentou influência apenas para fósforo trocável enquanto que a embalagem não influiu nos resultados. As variações dos resultados analíticos para pH, em função da secagem, e fósforo, em função da secagem e tempo de armazenamento, foram de ordem a alterar a interpretação da fertilidade quanto aos limites de classes.; Soil samples were chemically analysed to verify the influence of packing (card box or poliethylene bag), storage (1-32 days) and drying process (in the open air or at 60°C). The types of soil under consideration were Terra Roxa Estruturada and Dark Red B Latosolic sand phase. The drying process was the most important factor affecting analytical results of pH and phosphorus. The storage showed importance only to phosphorus, and the packing process had no influence in the results. Variations on the level of soil fertility were also obtained. Statistical analysis applied on the results showed that drying is the main factor affecting the chemical analysis...

Analise quimica de residuos solidos para estudos agroambientais; Chemical analysis of solid waste for agricultural and environmental studies

Audrey de Arruda Falcão
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 12/07/2005 PT
Relevância na Pesquisa
55.96%
A prática de utilizar resíduos orgânicos e inorgânicos como fertilizantes é cada vez mais importante na agricultura. Os riscos da disposição indiscriminada de resíduos no solo são associados principalmente com o transporte dos poluentes pela infiltração dos líquidos percolados, que são responsáveis pela contaminação do subsolo e das águas subterrâneas. Antes de ser usado na agricultura, o resíduo deve ser analisado para verificar se não contém substâncias incluindo microrganismos, em quantidades que possam ser prejudiciais ao solo e às águas subterrâneas. Há relativamente poucos métodos de referência para a análise química de tais resíduos. De uma maneira geral, os métodos recomendados para a análise dos resíduos são aqueles geralmente empregados para análises de solo. Assim o objetivo do presente projeto é avaliar e selecionar os métodos usados nas análises de solos que poderiam ser utilizados para caracterizar resíduos inorgânicos e orgânicos, solo e a mistura desses três. Isto torna possível analisar a viabilidade do uso agrícola de diferentes tipos de resíduos. Os métodos avaliados foram baseados nos procedimentos existentes e usados oficialmente nos EUA pela EPA (Agência de Proteção Ambiental) e no Brasil pelo IAC (instituto Agronômico de Campinas) para análises de solos. Os resultados deste estudo agroambiental permitem a avaliação das diferentes características químicas do resíduo...

Spatial variability of some biometricattributes of sugarcane plants (variety IACSP93-3046) and its relation to physical and chemical soil attributes

Grego,Célia Regina; Vieira,Sidney Rosa; Xavier,Mauro Alexandre
Fonte: Instituto Agronômico de Campinas Publicador: Instituto Agronômico de Campinas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 EN
Relevância na Pesquisa
55.9%
Tests to evaluate competition between plants, in general do not consider the soil spatial variability, nevertheless, the uniformity rarely is present and can not be assumed without verification. The aim of this work was to apply geostatistics to verify the spatial variability of the soil in an experimental field near Ribeirão Preto, SP, with sugarcane variety IACSP93-3046. Ninety seven geo-referenced samples, placed at distances of 10 m, were collected for soil chemical analysis, soil resistance to penetration and biometric evaluation of the sugar cane plant included number of tillers, stalk diameter, stalk height, estimated productivity (TSSe) and root density. Geostatistics has been applied by means of semivariogram, data interpolation via kriging and iso-line maps creation. The results have shown soil spatial dependence for most of the evaluated attributes. The spots, within the area, with low resistance to penetration and low soil density have shown the largest number of tillers and the largest root development of sugar cane. For soil chemical attributes, there was spatial dependence showing higher concentration of nutrients in the central area. The sampling allowed a good representativity of the spatial dependence of soil and plants...

Influence of organic-mineral fertilization of an oxisol on soil chemical properties and Bracharia brizantha production

Schiavoni,Edmar Andrade; Alves,Marlene Cristina; Souza,Zigomar Menezes de; Costa,Frederick Gonçalves
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 EN
Relevância na Pesquisa
55.95%
The use of organic-mineral fertilizer produced by the manufacturing industry of lysine and threonine amino acids can improve the fertility of tropical soils. The objective of this study was to evaluate the influence of different doses of the organic-mineral fertilizer named Ajifer L-14 on chemical properties and on the response with increased production of a forage on a Red Latosol in the northwestern region of São Paulo State, Brazil. A randomized block design was used with seven treatments and four replications. The treatments consisted of: T1- control (without application of Ajifer L-14); T2- control (natural vegetation); T3- mineral fertilization according to crop requirements and soil analysis (application of 1.35 kg plot-1 of urea, 2.20 single superphosphate, and 0.51 KCl, corresponding to 60 of N, 40 P2O5 and 30 kg ha-1 of K2O); T4- fertilization with Ajifer L-14 according to the recommendation resulting from the soil chemical analysis (40 L plot-1, corresponding to 60 kg ha-1 N); T5- fertilization with Ajifer L-14, at a rate of 150 % of the recommended values (60 L plot-1, corresponding to 90 kg ha-1 N); T6- fertilization with Ajifer L-14 at a rate of 50 % of the recommended values (20 L plot-1, corresponding to 30 kg ha-1 N); T7- fertilization with Ajifer L-14 at a rate of 125 % of the recommended values (50 L plot-1...

Characterization of soil chemical properties of strawberry fields using principal component analysis

Islabão,Gláucia Oliveira; Pinto,Marília Alves Brito; Selau,Lisiane Priscila Roldão; Vahl,Ledemar Carlos; Timm,Luís Carlos
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2013 EN
Relevância na Pesquisa
55.95%
One of the largest strawberry-producing municipalities of Rio Grande do Sul (RS) is Turuçu, in the South of the State. The strawberry production system adopted by farmers is similar to that used in other regions in Brazil and in the world. The main difference is related to the soil management, which can change the soil chemical properties during the strawberry cycle. This study had the objective of assessing the spatial and temporal distribution of soil fertility parameters using principal component analysis (PCA). Soil sampling was based on topography, dividing the field in three thirds: upper, middle and lower. From each of these thirds, five soil samples were randomly collected in the 0-0.20 m layer, to form a composite sample for each third. Four samples were taken during the strawberry cycle and the following properties were determined: soil organic matter (OM), soil total nitrogen (N), available phosphorus (P) and potassium (K), exchangeable calcium (Ca) and magnesium (Mg), soil pH (pH), cation exchange capacity (CEC) at pH 7.0, soil base (V%) and soil aluminum saturation(m%). No spatial variation was observed for any of the studied soil fertility parameters in the strawberry fields and temporal variation was only detected for available K. Phosphorus and K contents were always high or very high from the beginning of the strawberry cycle...

Relationships between microbial activity and soil physical and chemical properties in native and reforested Araucaria angustifolia forests in the state of São Paulo, Brazil

Pereira,Jamil de Morais; Baretta,Dilmar; Bini,Daniel; Vasconcellos,Rafael L. de F.; Cardoso,Elke Jurandy Bran Nogueira
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
Relevância na Pesquisa
56.04%
Araucaria angustifolia (Bert.) O. Kuntze is the main component of the Mixed Ombrophilous forest and, in the State of São Paulo, it is associated with a high diversity of soil organisms, essential for the maintenance of soil quality, making the conservation of this ecosystem a major and pressing challenge. The objective of this study was to identify the physical and chemical properties that are most closely correlated with dehydrogenase enzyme activity, basal respiration and microbial biomass under native (NF) and replanted (RF) Araucaria angustifolia forests in three regions of the state of São Paulo, in winter and summer. The main differentiating factors between the areas were also determined. Each forest was represented by three true replications; at each site, from around the araucaria trees, 15 soil samples (0-20 cm) were collected to evaluate the soil physical, chemical and microbiological properties. At the same points, forest litter was sampled to assess mass and chemical properties. The following microbiological properties were evaluated: microbial biomass carbon (MBC), basal respiration (CO2-C), metabolic quotient (Q: CO2), dehydrogenase enzyme activity (DHA) as well as the physical properties (moisture, bulk density, macroporosity and total porosity)...

Organic carbon determination in histosols and soil horizons with high organic matter content from Brazil

Pereira,Marcos Gervasio; Valladares,Gustavo Souza; Anjos,Lúcia Helena Cunha dos; Benites,Vinícius de Melo; Espíndula Jr.,Ademar; Ebeling,Adierson Gilvani
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2006 EN
Relevância na Pesquisa
55.81%
Soil taxonomy systems distinguish mineral soils from organic soils based on the amount of soil organic carbon. Procedures adopted in soil surveys for organic carbon measurement are therefore of major importance to classify the soils, and to correlate their properties with data from other studies. To evaluate different methods for measuring organic carbon and organic matter content in Histosols and soils with histic horizons, from different regions of Brazil, 53 soil samples were comparatively analyzed by the methods of Walkley & Black (modified), Embrapa, Yeomans & Bremner, modified Yeomans & Bremner, muffle furnace, and CHN. The modified Walkley & Black (C-W & B md) and the combustion of organic matter in the muffle furnace (OM-Muffle) were the most suitable for the samples with high organic carbon content. Based on regression analysis data, the OM-muffle may be estimated from C-W & B md by applying a factor that ranges from 2.00 to 2.19 with 95% of probability. The factor 2.10, the average value, is suggested to convert results obtained by these methods.

Prediction of soil chemical attributes using optical remote sensing

Genú,Aline Marques; Demattê,José Alexandre Melo
Fonte: Editora da Universidade Estadual de Maringá - EDUEM Publicador: Editora da Universidade Estadual de Maringá - EDUEM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 EN
Relevância na Pesquisa
55.88%
Soil fertility variability management is one of the pioneering and important areas in which Precision Agriculture has been commercially applied. Consequently, the objective of this work was to predict soil chemical attributes through spectral responses. The 1,000 ha study area used for this report was located in Uberlândia, MG, Brazil. Thirty sampling points were established, at which the soil was collected at 3 different depths. The samples were chemically and physically analyzed and the radiometric data obtained in the 400 - 2500 nm range. Multiple regression equations were generated for sum of bases, cation exchange capacity, base saturation, aluminum saturation, pH, P, K, Ca, Mg, Al, and H, all using 60 soil samples. H, Al, m%, and pH were found to have R² values less than 0.50. Equations with an R² > 0.50 for the other attributes were tested for the 30 unknown soil samples, and the estimated values were obtained. These values were then compared with those determined by conventional analysis. The coefficients of correlation were higher than 50% for all attributes except P and V%. Results indicated that determining chemical attributes with models that are specific for the region is feasible.

Spatial variability of some biometric attributes of sugarcane plants (variety IACSP93-3046) and its relation to physical and chemical soil attributes.

GREGO, C. R.; VIEIRA, S. R.; XAVIER, M. A.
Fonte: Bragantia, Campinas, v. 69, suplemento, p. 107-119, 2010. Publicador: Bragantia, Campinas, v. 69, suplemento, p. 107-119, 2010.
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
55.9%
Tests to evaluate competition between plants, in general do not consider the soil spatial variability, nevertheless, the uniformity rarely is present and can not be assumed without verification. The aim of this work was to apply geostatistics to verify the spatial variability of the soil in an experimental field near Ribeirão Preto, SP, with sugarcane variety IACSP93-3046. Ninety seven geo-referenced samples, placed at distances of 10 m, were collected for soil chemical analysis, soil resistance to penetration and biometric evaluation of the sugar cane plant included number of tillers, stalk diameter, stalk height, estimated productivity (TSSe) and root density. Geostatistics has been applied by means of semivariogram, data interpolation via kriging and iso-line maps creation. The results have shown soil spatial dependence for most of the evaluated attributes. The spots, within the area, with low resistance to penetration and low soil density have shown the largest number of tillers and the largest root development of sugar cane. For soil chemical attributes, there was spatial dependence showing higher concentration of nutrients in the central area. The sampling allowed a good representativity of the spatial dependence of soil and plants...

A Predictive Model of the Effects of Aging on Cobalt Fate and Behavior in Soil

Wendling, L.; Ma, Y.; Kirby, J.; McLaughlin, M.
Fonte: Amer Chemical Soc Publicador: Amer Chemical Soc
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
55.87%
Metal toxicity to terrestrial organisms is influenced by a number of factors including the organisms affected and ecotoxicological end points, soil properties, aging processes, and metal speciation. The toxicity of metals added to soils can change over time through aging processes, which may reduce availability of metals via diffusion into micropores, incorporation into crystal lattices, or Ostwald ripening of precipitates. Metals which have been in contact with soil for longer periods are less able to exchange with the soil solution, rendering them less available to soil biota. The objective of this work was to investigate and model the effects of longterm aging on cobalt(II) (Co2+) (isotopic) exchangeability and potential bioavailability in a wide range of soils, as this is the form of Co commonly used in ecotoxicological investigations. After addition to soil, added soluble Co(II) rapidly partitioned to the soil solid phase, and in alkaline soils a large percentage of this surface-bound Co was fixed through aging reactions in forms that were no longer in equilibrium with the soil solution Co. Analyses indicated that soil pH and incubation time were the most important factors affecting Co(II) aging. The rate and extent of aging of added Co(II) could be accurately predicted across all soils using a semi-mechanistic model that suggested Co was fixed through reactions that we postulate were related to surface oxidation/precipitation nucleation as driven by hydrolysis reactions at the surface of soil minerals.; Laura A. Wendling...

Assessment of the spatial variability of soil chemical properties along a transect using multifractal analysis

Dafonte Dafonte, J.; Valcárcel Armesto, M.; Da Silva Días, R.; Vidal Vázquez, E.; Paz González, A.
Fonte: Universidade da Coruña Publicador: Universidade da Coruña
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
55.89%
[Abstract]The spatial variability of soil properties can be assessed through concepts of scale invariance, fractals and multifractals. The aim of this study was to characterize the scaling patterns and structural heterogeneity properties of general soil chemical properties along a short (i.e. 52 m large) transect. Field measurements were carried out at the experimental farm of CIAM located in Mabegondo, A Coruña, Spain. The studied transect was marked following land slope, and 66 soil samples were collected at the 0-20 cm depth every 0.8 m. The soil properties analyzed were: pH (H2O ), organic carbon content, exchangeable Ca, Mg and K, exchangeable acidity (H + Al), exchangeable bases (SB), cation exchange capacity (CEC), percent base saturation (V) and extractable P. The soil properties studied showed various degrees of multifractality. The spatial distribution of pH was characterized by quasi-monofractal behaviour; CEC, (H+Al) and OM, presented a relatively low degree of multifractality, and the other soil properties studied showed stronger degrees of multifractality, being the highest one for Olsen extractable P. In general, the scaling features of the properties studied implied a multifractal nature, where the low and high density regions scaled differently.

Potassium fertilization for pineapple: effects on soil chemical properties and plant nutrition

Teixeira,Luiz Antonio Junqueira; Quaggio,José Antonio; Cantarella,Heitor; Mellis,Estêvão Vicari
Fonte: Sociedade Brasileira de Fruticultura Publicador: Sociedade Brasileira de Fruticultura
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2011 EN
Relevância na Pesquisa
55.9%
A field experiment was carried out on an Ultisol located at the city of Agudos (22º30'S; 49º03'W), in the state of São Paulo, Brazil, in order to determine the effects of rates and sources of potassium fertilizer on nutritional status of 'Smooth Cayenne' pineapple and on some soil chemical properties. The experiment was a complete factorial design with four rates (0, 175, 350, and 700 kg ha-1 of K2O) and three combinations of K sources (100% KCl, 100% K2SO4 and 40% K2SO4 + 60% KCl). Soil samples were taken from the depths 0-20 cm, 20-40 cm and 40-60 cm at planting and 14 months after. Nutritional status of pineapple plants was assessed by means of tissue analysis. Soil K availability increased with application of K fertilizer, regardless of K sources. Soil chlorine and Cl concentration in pineapple leaves increased with application of KCl or K2SO4+KCl. Plant uptake of potassium was shaped by soil K availability and by the application rates of K fertilizer, independently of K sources.

Influence of Soil Chemical Variables and Altitude on the Distribution of High-alpine Plants: the Case of the Andes of Central Chile

Casale, Jean Francois; Fuente, Luz María de la; Bustamante, Elena; Ginocchio, Rosanna; Montenegro, Gloria; Díaz Forester, Javiera; Harpe, Jean Paul de la; Anic, Vinka
Fonte: INST ARCTIC ALPINE RES, UNIV COLORADO Publicador: INST ARCTIC ALPINE RES, UNIV COLORADO
Tipo: Artículo de revista
EN
Relevância na Pesquisa
55.98%
Artículo de publicación ISI; Temperature is one of the major abiotic factors influencing distribution and productivity of alpine plant species. Although some edaphic parameters (e.g. soil acidity) have also been suggested as determinants in the spatial distribution of alpine vegetation, there is little background on the importance of soil chemical properties in altitudinal gradients, particularly in the high Andes. The present study determined whether soil chemical properties affect spatial distribution and abundance of alpine plants in an altitudinal gradient in the Andes of central Chile, emphasizing metal content. A direct gradient analysis took place at Yerba Loca Natural Sanctuary (YLNS), based on a geobotanical sampling conducted in 73 sites distributed from 1970 to 3330 m a.s.l. According to a Canonical Correspondence Analysis, the main soil chemical factors that explain the pattern of compositional variation of high Andean vegetation are, besides altitude, total soil copper (Cu) content, percentage of soil organic matter, and available phosphorus and nitrogen. An analysis of shoot Cu content conducted in 19 plant species found in sites with highest soil Cu contents (.250 mg kg21) showed high levels of Cu in their shoots (.100 mg kg21). These results demonstrate species or ecotypes with optimal distribution in soils with high Cu contents...

Influence of soot carbon on the soil-air partitioning of polycyclic aromatic hydrocarbons

Ribes, Sandra; Van Drooge, Barend L.; Dachs, Jordi; Gustafsson, Ørjan; Grimalt, Joan O.
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
Relevância na Pesquisa
55.79%
6 pages, 3 figures, 3 tables.-- PMID: 12854704 [PubMed].-- Printed version published Jun 15, 2003.; Soil−air partitioning is one of the key processes controlling the regional and global cycling and storage of polycyclic aromatic hydrocarbons (PAHs). However, the specific processes dominating the partitioning of PAHs between these two environmental compartments still need to be elucidated. Stable and distinct atmospheric conditions paralleling different soil properties are found at Tenerife island (28°18‘N, 16°29‘W), which is located in permanent inversion layer conditions, and they provide interesting model cases for the study of air−soil partitioning. Analysis of phenanthrene, pyrene, fluoranthene, and chrysene showed concentrations 4- to 10-fold higher below than above the inversion layer. Similarly, soil total organic carbon (TOC) and black carbon (BC) were 11 and 3 times higher, respectively, below the inversion layer than above. The octanol−air partition coefficient (KOA) derived model provides a good description of PAH soil−air partitioning coefficients (KP) below the inversion layer but underpredicts them in the area dominated by deposition of long-range transported aerosols without inputs of organic matter from local vegetation. Inclusion of soot carbon in the soil−air partitioning model results in good agreement between predicted and measured KP in this area but in overpredicted KP values for the soils under the vegetation cover...

Influência da secagem, armazenamento e embalagem nos resultados da análise química de terra para fins de fertilidade; Influence of packing, storage and drying process on the results of soil chemical analysis related to soil fertility

Chitolina, J.C.; Glória, N.A.da; Boaretto, A.E.; Curi, P.R.
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/01/1989 POR
Relevância na Pesquisa
85.95%
Amostras de terra provenientes de uma Terra Roxa Estruturada e um Latossol Vermelho Escuro textura média foram analisados quimicamente para se verificar a influência de embalagem (caixa de papelão saco de polietileno), tempo de armazenamento (1-32 dias) e processo de secagem (ao ar ou estufa a 60°C). A secagem foi o fator que mais influenciou a análise determinando variações nos resultados analíticos principalmente para pH e fósforo. O armazenamento apresentou influência apenas para fósforo trocável enquanto que a embalagem não influiu nos resultados. As variações dos resultados analíticos para pH, em função da secagem, e fósforo, em função da secagem e tempo de armazenamento, foram de ordem a alterar a interpretação da fertilidade quanto aos limites de classes.; Soil samples were chemically analysed to verify the influence of packing (card box or poliethylene bag), storage (1-32 days) and drying process (in the open air or at 60°C). The types of soil under consideration were "Terra Roxa Estruturada" and Dark Red B Latosolic sand phase. The drying process was the most important factor affecting analytical results of pH and phosphorus. The storage showed importance only to phosphorus, and the packing process had no influence in the results. Variations on the level of soil fertility were also obtained. Statistical analysis applied on the results showed that drying is the main factor affecting the chemical analysis...

Determinação do carbono orgânico em organossolos e solos com horizontes com elevado conteúdo de matéria orgânica; Organic carbon determination in histosols and soil horizons with high organic matter content from Brazil

Pereira, Marcos Gervasio; Valladares, Gustavo Souza; Anjos, Lúcia Helena Cunha dos; Benites, Vinícius de Melo; Espíndula Jr., Ademar; Ebeling, Adierson Gilvani
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/04/2006 ENG
Relevância na Pesquisa
55.81%
Sistemas taxonômicos distinguem horizontes e/ou camadas minerais das orgânicas baseando-se na quantidade de carbono orgânico. Assim, o procedimento adotado em pesquisas para a quantificação do conteúdo de carbono orgânico é de grande importância para a classificação das terras e correlacionar as suas propriedades com dados de outros estudos. Com o objetivo de avaliar os diferentes métodos para medir o conteúdo de carbono orgânico e de matéria orgânica em Organossolo e solos com elevados teores de matéria orgânica, de diferentes regiões do Brasil, cinqüenta e três amostras de terra foram comparativamente analisadas pelos métodos de Walkley & Black (modificado), Embrapa, Yeomans & Bremner, Yeomans & Bremner modificado, forno mufla, e CHN. O método Walkley & Black modificado (C-W & B md) e a combustão de matéria orgânica no forno mufla (MO-Mufla) revelaram-se mais satisfatórios para as amostras com elevado conteúdo de carbono orgânico. Com base em dados de análise de regressão, os teores de matéria orgânica determinados pela mufla podem ser calculados a partir dos dados de C-W & B md aplicando-se um fator que varia de 2,00 a 2,19 com 95% de probabilidade. O fator 2,10, valor médio, é sugerido para a conversão dos resultados obtidos por estes métodos.; Soil taxonomy systems distinguish mineral soils from organic soils based on the amount of soil organic carbon. Procedures adopted in soil surveys for organic carbon measurement are therefore of major importance to classify the soils...