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Search Results: 1 - 10 of 7876 matches for " Albuquerque Jackson Adriano "
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Aplica??o de resíduo alcalino na superfície de Cambissolos
Albuquerque, Jackson Adriano;Medeiros, Jo?o Carlos;Costa, André da;Rengel, Maicon;
Bragantia , 2011, DOI: 10.1590/S0006-87052011000400023
Abstract: the cellulose industry produce a large amount of residues, and some have potential to improve the soil fertility. however, there is still lack of information about the viability of use and the doses to be applied to the soil. the aims of this study were to evaluate the use of an alkaline residue (dregs) as acidity corrective and measure the changes in the chemical and physical attributes of two cambisols, one clay loam and another sandy loam. the experiment was performed in pots in a greenhouse, with superficial application of dregs in the proportion of 0%, 12%, 35%, 50% and 100% of the equivalent rate of caco3 required to increase the ph to 6.0. the maize crop was grown until 40 days after germination to quantify the dry matter of roots and shoots. in soil not cultivated with maize, samples were collected to evaluate the aggregate stability, clay dispersion, ph, and content of exchangeable cations. the addition of surface dregs increases the ph, ca, k and mg, and reduces the content of exchangeable al, mainly in the soil layer of 0 to 5 cm. however, harmful effects are observed, as the increase in the content of na, the ca/mg ratio and dispersion of clay. changes in soil chemical properties favor the growth of roots and shoots of maize until the dose equivalent to the dregs from 40 to 47% of the need for lime to raise the water ph to 6.0. above these doses plant development is constrained.
Tens?o e extra??o de água em mesa de tens?o e coluna de areia, em dois solos com elevada densidade
Gubiani, Paulo Ivonir;Albuquerque, Jackson Adriano;Reinert, Dalvan José;Reichert, José Miguel;
Ciência Rural , 2009, DOI: 10.1590/S0103-84782009005000199
Abstract: the determination of moisture content in soils under tension follows the assumption that the water matric potential is at equilibrium with an applied tension. the time the soil water tension reaches the equilibrium under the 6kpa tension was determined in hapludalf and hapludox clay soils. in the hapludalf, the equilibrium between the applied tension and water matric potential, in most of the samples, was obtained between 72 and 96h, while in hapludox, equilibrium was not reached until the 168h. the water tension in the samples had no significant correlation with bulk density and did not reach the tension applied on the suction table and sand suction column. nevertheless, more than 97% of the soil water was extracted at 48h both in hapludalf and hapludox, suggesting that this time is sufficient to estimate the soil moisture at 6kpa tension, independently of clay content.
Atributos químicos de um Cambissolo Húmico após 12 anos sob preparo convencional e semeadura direta em rota??o e sucess?o de culturas
Andrade, Andréia Patrícia;Mafra, álvaro Luiz;Picolla, Cristiano Della;Albuquerque, Jackson Adriano;Bertol, Ildegardis;
Ciência Rural , 2012, DOI: 10.1590/S0103-84782012005000013
Abstract: suitable soil management is one of the bases for sustainability in agricultural systems. the study aimed to evaluate chemical properties of a humic dystrudept for 12 years under two tillage systems, with crops rotation and succession. the experiment was carried out in lages, sc, under conventional tillage (ct) and no-till (nt), with rotation (r) and succession (s) cropping systems, using crop sequences of beans-fallow-maize-fallow-soybean in ctr; maize-fallow in cts; beans-oats-maize-fodder radish-soybean-vetch in ntr; and maize-vetch in nts. the experimental design was completely randomized with four replicates. the soil samples were collected in the layers 0-2.5, 2.5-5, 5-10 and 10-20cm. the variables assessed were total organic carbon (toc), calcium, magnesium, exchangeable aluminum, phosphorus, potassium, total nitrogen (tn) and water ph. the no-tillage system increased toc and nutrient levels in comparison with conventional tillage, especially in the surface soil layer. maize and vetch crop succession had higher toc and tn contents in the surface soil layer compared to crop rotation under no-tillage.
Atributos físicos de um Latossolo Vermelho e produtividade de culturas cultivadas em sucess?o e rota??o
Genro Junior, Silvio Aymone;Reinert, Dalvan José;Reichert, José Miguel;Albuquerque, Jackson Adriano;
Ciência Rural , 2009, DOI: 10.1590/S0103-84782009000100011
Abstract: this study had as objective to evaluate the effects of crops succession and rotation on physical properties and crops yield on an oxisol (clayey haplortox) under no tillage system, in rio grande do sul state, brazil. the treatments included four cropping sequences, used from 1998 to 2001: 1) succession wheat / soybean, 2) rotation corn / oat / corn+ cajanus cajan l. millsp / wheat / soybean / wheat, 3) rotation cajanus cajan l. millsp / wheat / soybean / wheat / soybean / oat, and 4) rotation crotalaria juncea l. / wheat / soybean / oat / corn / wheat. in october of 2000 and 2001, soil samples were collected to determine physical properties. in all years, the crops yield was measured. the oxisol cultivated under no-tillage had a high compaction degree, with soil bulk density greater and macroporosity smaller than the critical limit for clay texture. the largest limitations were observed below the layer of 0 to 0,03m, because in the uppermost layer soil mobilization by successive operations of fertilization and sowing increases soil porosity and reduces soil density. thus, greater volume of pores is observed between soil saturation and field capacity, responsible for soil aeration, and between field capacity and wilting point, responsible for storage of plant available water. the use of cover crops once every three years was not efficient to reduce soil compaction. the yield of the subsequent crops was influenced positively in the rotation with crotalaria juncea, while the other cropping systems did not differ from crop succession.
Matéria organica e aumento da capacidade de troca de cátions em solo com argila de atividade baixa sob plantio direto
Ciotta, Marlise Nara;Bayer, Cimélio;Fontoura, Sandra Mara Vieira;Ernani, Paulo Roberto;Albuquerque, Jackson Adriano;
Ciência Rural , 2003, DOI: 10.1590/S0103-84782003000600026
Abstract: soil management affects the organic matter stocks, and thus the cec especially in low activity clay soils. the main goal of this study was to evaluate the long-term (21 years) effect of the no-tillage on soil organic carbon (soc) stocks and its relationship with cec increase in a clayey oxisol (hapludox), in guarapuava (pr), southern brazil. no-tillage soil had only 2.63t ha-1 more soc than conventionally tilled soil at 0-20cm, and the highest net accumulation occurred in soil surface layers (0-6cm). the low accumulation rate of soc in the no-tilled soil (0,12t ha-1 yr-1) was related to the high physical stability of soil organic matter in this clayey oxisol. despite the small effect on soc contents, the no-tilllage had an expressive influence on the cec of 0-8cm soil layer. the effective cec increased 15.2mmolckg-1 and the potential (ph 7.0) cec increased 20.7mmolckg-1 in this soil layer, in comparison to conventional tillage system. the results support the positive effect of no-tillage on soil organic matter stocks and on cec of tropical and subtropical soils with predominantly low activity clay minerals.
Calagem e as propriedades eletroquímicas e físicas de um latossolo em plantio direto
Costa, Falberni de Souza;Bayer, Cimélio;Albuquerque, Jackson Adriano;Fontoura, Sandra Mara Vieira;
Ciência Rural , 2004, DOI: 10.1590/S0103-84782004000100045
Abstract: in this study there has been an evaluation of (i) the liming effect on some electrochemical and physical properties of a no-tilled oxisol (haplohumox) for 21 years, and (ii) the effect of soil disturbance to lime incorporation on soil physical properties. liming increased the surface electric potential, regardless of lime application method, and the estimated values varied from (-) 90mv to (-) 118mv. however, the amount of clay dispersed in water was not affected by liming, probably due to its negative relationship with total organic carbon (toc) and ca+mg concentrations, with the greatest values occurring in soil surface layers. the liming had no effect on the mean geometric diameter (mgd) of soil aggregates, which was positively related to toc stock of the different soil layers. after five years, no negative effect of plow and disking to lime application into the soil was observed for mgd and porosity of this clayey (690 g kg-1 clay) and gibbsitic oxisol, in comparison to surface liming treatment. in addition to the favorable conditions to microbial activity, the highest toc and ca+mg in the surface layers of no-tillage soils contribute to mitigated the effect of liming on clay dispersion.
Aumento de matéria organica num latossolo bruno em plantio direto
Costa, Falberni de Souza;Bayer, Cimélio;Albuquerque, Jackson Adriano;Fontoura, Sandra Mara Vieira;
Ciência Rural , 2004, DOI: 10.1590/S0103-84782004000200041
Abstract: the increase of soil organic matter stocks under conservation management systems is dependent of soil type and regional climatic conditions, and has influence on the physical quality of soils. in this study the long-term (21 yr) effect of no-tillage on total soil organic carbon (toc) and particulate organic carbon (poc, >53mm), as well as its relationship with aggregate stability of a south brazilian oxisol (haplohumox), was evaluated. in comparison with toc stocks of conventionally-tilled soil, no-tillage soil had a net storage of 0.15mg ha-1 yr-1 of toc, and 0.06mg ha-1 yr-1 of poc, in the 0-20cm soil layer. these low accumulation rates of organic carbon probably were due to the high clay content and gibbsitic mineralogy of the soil, which determine a great physical stability of soil organic matter. the mean geometric diameter (mgd) of soil aggregates varied from 1.6 to 3.7mm, and had a positive relationship with toc and poc, reinforcing the crucial role of organic matter on physical quality of subtropical oxisols.
Recupera??o da qualidade estrutural, pelo sistema plantio direto, de um Argissolo Vermelho
Flores, Carlos Alberto;Reinert, Dalvan José;Reichert, José Miguel;Albuquerque, Jackson Adriano;Pauletto, Eloy Antonio;
Ciência Rural , 2008, DOI: 10.1590/S0103-84782008000800012
Abstract: soils with high sand content in the a horizon are prone to degradation processes, depending on management system used. this study had as objective to evaluate the degradation of a hapludalf formed from granite, located in the passo do pil?o watershed in pelotas county, cultivated under conventional system, and its recovery by no-tillage system, compared to two native systems, namely grass field and forest. the experiment was setup in an agricultural area, in april of 1995, with the cultivation of avena strigosa plus vicia vilosa, both for conventional system and no-tillage. an area under native grasses and another with native forest were sampled for comparison. soils samples were colleted from the layers of 0-0.05m, 0.10-0.15m and 0.20-0.25m, to determine the soil texture, porosity, densities, water retention, aggregate stability and distribution, and organic carbon content. the cultivation systems increase the soil bulk density and reduce total porosity, microporosity, water retention and availability, compared with native systems such as grass field and forest. the conventional system reduces organic carbon content and aggregate stability, whereas no-tillage, after five years, increases, somewhat, the organic carbon content in the surface layer, but increases aggregate stability to values near of those for native systems. the aggregate stability had direct relationship with organic carbon content up to an upper limit of 25g kg-1. the bulk density, macroporosity, s parameter, organic carbon content and aggregate stability are good indicators of the changes observed in the soil management systems. for the hapludalf formed from granite, there was recovery of the properties related to soil structure stability, but in those related to soil bulk density and porosity no recovery was observed.
Yield and fruit quality of apple from conventional and organic production systems
Amarante, Cassandro Vidal Talamini do;Steffens, Cristiano André;Mafra, álvaro Luiz;Albuquerque, Jackson Adriano;
Pesquisa Agropecuária Brasileira , 2008, DOI: 10.1590/S0100-204X2008000300007
Abstract: the objective of this study was to assess the yield and fruit quality of apple produced with a conventional and an organic production systems in southern brazil. the orchards consisted of alternate rows from 10 to 12-year old 'royal gala' and 'fuji' apple trees on m.7 rootstocks, grown as slender spindles, on 4x6 m spacing. eighteen apple trees of each cultivar and management system were randomly selected and assessed for nutrition, flowering, fruit set, yield, and fruit quality during two growing seasons (2002/2003 and 2003/2004). the organic management system resulted in lower concentrations of k, mg, and n in leaves and fruits, and in smaller fruits for both cultivars, and lower fruit yield for 'fuji' than from the conventional production system. for both cultivars, fruits from the organic orchard harvested at commercial maturity had a more yellowish skin background color, higher percentage of blush in the fruit skin, higher soluble solids content, higher density, higher flesh firmness, and higher severity of russet than fruits from the conventional orchard. fruit from the organic orchard had lower titratable acidity in 'royal gala', and higher incidence of moldy core and lower incidence of watercore in 'fuji', than fruit from the conventional orchard. a non-trained sensory panel detected no significant differences for fruit attributes of taste, flavor and texture between fruit from the production systems for either cultivar.
Influência da adi??o de um resíduo alcalino da indústria de papel e celulose na lixivia??o de cátions em um solo ácido
Almeida, Henrique Cesar;Ernani, Paulo Roberto;Albuquerque, Jackson Adriano;Mecab? Junior, José;Almeida, Denice;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000400042
Abstract: alkaline by-products generated in the pulp and paper industry can be used to reduce soil acidity. however, the low mg and intermediate na values in these residues can negatively affect the bioavailability of some nutrients and soil properties. before recommending them, it is therefore imperative that their effects on the soil be evaluated. the objective of this study was to quantify the soil chemical composition and vertical mobility of cations due to application of alkaline industrial residue in different forms, in comparison to dolomitic limestone. the experiment was carried out in a laboratory, with a haplumbrept, from 2005 to 2006, using leaching columns (30 x 10 cm diameter). the treatments consisted of a 4 x 2 x 2 factorial design, including two previous values of soil ph with one control each, two alkaline compounds (industrial residue or dolomitic limestone) and two application methods (surface applied or soil incorporated). ten percolations were performed, at weekly intervals, in a volume of 300 ml of distilled water per week, corresponding to a total amount of 380 mm rain. 60 % of the na added leached from the soil-incorporate by-product, but this leaching decreased to 12 % when it was applied on the soil surface. the addition of alkaline residue did not cause leaching of ca, mg or k, and dolomitic limestone leached only 2.4 % of the ca and 7.2 % of added mg, demonstrating the low vertical mobility of these cations when applied from basic compounds to variable charge soils. the previous elevation of the soil ph decreased cation leaching substantially due to the increase of the soil negative charges. given the rainfall conditions in southern brazil, the amount of na added will disappear from the plow layer in less than one year after its application, so this product should not negatively affect any chemical or physical soil property.
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