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Fontes de potássio em solos distroférricos cauliníticos originados de basalto no Rio Grande do Sul
Melo, G. W.;Meurer, E. J.;Pinto, L. F. S.;
Revista Brasileira de Ciência do Solo , 2004, DOI: 10.1590/S0100-06832004000400002
Abstract: the objective of this study was to identify the k-bearing minerals as well as the granulometric fraction of the soil with potential to supply k to the plants from two basaltic oxisols (hapludox and kandiudox). the mineralogical analyses of the granulometric fractions of the hapludox soil revealed the probable occurrence of a mica mineral in the fine silt and coarse clay fractions, while feldspar minerals occurred in the sand, coarse silt, and fine silt fractions. in the kandiudox soil, a probable mica mineral was observed in the coarse silt, fine silt, and coarse clay fractions, whereas feldspar minerals were observed in the sand and silt fractions. in both soils, the presence of a 2:1 clay mineral with hydroxy interlayer material (2:1 ehi) was also observed. this clay mineral has the basic structure of a smectite mineral. the coarse clay fraction of both soils presented the strongest evidences of the presence of k-bearing minerals, representing the most promising fraction for k supply to plants.
Levantamento de solos e interpreta??o fotográfica dos padr?es desenvolvidos em solos originados do arenito de Bauru
Fran?a, G.V. de;Demattê, J.A.M.;
Scientia Agricola , 1993, DOI: 10.1590/S0103-90161993000100012
Abstract: drainage network and quantitative parameters necessary for pedologic interpretation were obtained by means of aerial photographs in the 1:25.000 scale. the study area has approximately 700 km2 and is located in the western part of sao paulo state. the rock substrate of the soils was identified as bauru sandstone. the composition of drainage networks in watersheds was determined to the third order of ramification; drainage densities were detennined by circular samples. drainage density values showed differences between podzolic soils and the red-yellow latosols. with the aid of this parameter it was possible to separate intergrade soil groups.
Rela??es solo-paisagem em uma litosseqüência arenito-basalto na regi?o de Pereira Barreto, SP
Campos, Milton César Costa;Marques Júnior, José;Pereira, Gener Tadeu;Montanari, Rafael;Camargo, Livia Arantes;
Revista Brasileira de Ciência do Solo , 2007, DOI: 10.1590/S0100-06832007000300012
Abstract: the focus of our study were to study soil-landscape relationships in a sandstone-basalt transition lithosequence and to compare the limits of geomorphic surfaces mapped in the field with those mapped by geostatistical techniques. an area of 530 ha was mapped using gps equipment in order to generate a model of digital elevation, which allowed for the establishment of a transection of 2.100 m from the hill top downwards. along the transection, the altitude was measured at 50 m regular intervals to construct the elevation profile. the geomorphic surfaces were identified and delimited according to topographic and stratigraphic criteria based on detailed field investigations. soil samples were collected at 67 points of the identified geomorphic surfaces, in the 0.0-0.25 m and 0.80-1.00 m depths. besides, trenches were opened in the slope segments of the mapped geomorphic surfaces. the samples were analyzed for bulk density, texture, ca, k, mg, sb, cec, v%, ph (water and kcl), sio2, al2o3 and fe2o3 (h2so4 attack), and "free" iron oxides extracted with dithionite-citrate-bicarbonate, while poorly crystallized iron was extracted with ammonium oxalate. the iron-free clay fraction was analyzed by x-ray diffraction. the compartmentalization of the area in geomorphic surfaces and the identification of the parent material explained well the variation in the soil attributes. an individual analysis of the soil attributes by univariate statistics contributed to the discrimination of the three geomorphic surfaces. geostatistical techniques confirmed the agreement of the limits determined by individualized soil attributes with those of the geomorphic surfaces.
Canteras taller de basalto en la zona de Bajo Caracoles - río Olnie (Provincia de Santa Cruz)  [cached]
Juan Bautista Belardi,Flavia Carballo Marina
Intersecciones en Antropología , 2005,
Abstract: Se relevaron canteras taller secundarias de basalto en la zona de Bajo Caracoles - río Olnie (noroeste de Santa Cruz), permitiendo proponer la ampliación del radio de disponibilidad regional de rocas de buena y muy buena calidad para la talla. La interpretación de cortes delgados de los materiales registrados aumenta la variabilidad petrográfica existente dentro de la denominación arqueológica y macroscópica del Basalto Posadas. Basalt secondary quarries were surveyed in the zone of Bajo Caracoles, Olnie River (NW of Santa Cruz), enabling a proposed extension of the regional availability radius of good and very good quality rocks for flint knapping. The interpretation of petrographic thin sections increases the existing petrographic variability within the archaeological and macrocospic denomination of Basalto Posadas.
Uso de imagens de satélite na discrimina??o de solos desenvolvidos de basalto e arenito na regi?o de Paragua?u Paulista
Demattê, José Alexandre M;Moreti, Dolorice;Vasconcelos, Ana Carolina Feitosa de;Genú, Aline Marques;
Pesquisa Agropecuária Brasileira , 2005, DOI: 10.1590/S0100-204X2005000700011
Abstract: the objective of this work was to evaluate soil characterization and discrimination by spectral information obtained from satellite sensor. soils presented variation on the spectral signature, and on their spectral intensity. typic argiudoll (alfisols) presented low spectral intensity, and typic quartzpisament presented a high spectral intensity. typic haplorthox (oxisols) presented increments in its reflectance according to the texture. eutrophic soils presented greater reflectance intensities than alic soils. the discriminate analyses indicate a 0.028% error. mistake samples occurred due to similar characteristics of soils. the methodology used to collect spectral data from satellite sensor showed to be efficient, and made possible soil discrimination, as well as faster soil survey of the presented region.
Impacto do Intemperismo no Arenito de Revestimento do Teatro Municipal de S o Paulo
Eliane Aparecida Del Lama,Gergely Andres Julio Szabó,Lauro Kazumi Dehira,Yushiro Kihara
Geologia USP : Série Científica , 2008,
Abstract: Um dos cart es postais da cidade de S o Paulo, o Teatro Municipal, construído em 1911, tem sua fachada frontalrevestida pelo Arenito Itararé. O arenito é proveniente da área da Flona (Floresta Nacional) de Ipanema em Iperó - SP, outroraReal Fábrica de Ferro de Ipanema, constituindo-se hoje num patrim nio histórico, arqueológico e natural. A fachada estábastante deteriorada, por causa do litotipo escolhido na sua constru o. O Arenito Itararé é estratificado, com marcantecaracterística sigmoidal, e tem granula o variada, desde fina a grossa. Petrograficamente, é um arenito feldspático com matrizargilosa em propor o variável. Análises de difra o de raios X apontam que a matriz argilosa é constituída por argilomineraisdo grupo da esmectita, com contribui o de clorita e illita. Apresenta porosidade de 10% a 18%, indicada por porosimetria demercúrio. O mapeamento da fachada identificou as seguintes formas de intemperismo: coloniza o biológica, concre o,eros o, escama o, fissura, incrusta o, junta aberta, lascagem, mancha, placa, plaqueta e vegeta o. A industrializa o e ocrescimento da cidade n o tiveram grande impacto na altera o do revestimento do Teatro Municipal de S o Paulo. Esteprocesso é intrínseco, devido às características petrográficas (presen a de argilominerais expansivos e alta porosidade) e aestrutura do arenito utilizado, inabilitando-o como pedra de revestimento.
Auba??o do feijoeiro em solos derivados do arenito Bauru
Miyasaka, Shiro;Igue, Kosen;Freire, E. S.;
Bragantia , 1965, DOI: 10.1590/S0006-87051965000100020
Abstract: seven fertilizer experiments were laid out in 1960-61 on soils of the ?arenito bauru? type, to study the effects of several treatments on the yields of dry beans. for determining the residual effect of the treatments, three of the experiments were repeated in 1961-62. in the average of the experiments of 1960-61, the responses to 60 and 120 kg/ha (kilograms per hectare) of p2o5 as ordinary superphosphate were +364 and +574 kg/ha of seeds and those due to 30 and 60 kg/ha of nitrogen as ammonium sulfate, +177 and +212 kg/ha, whereas those due to 45 and 90 kg/ha of k2o as potassium sulfate were -5 and -56 kg/ha. the average residual effect of phosphorus corresponded to +151 kg/ha and that of potassium was again negative. the addition of a mixture containing gypsum and micronutrients (zn, cu, b and mo) to a npk fertilizer practically sulfur-free increased the yields in all of the 1960-61 experiments, the average increase reaching 331 kg/ha. although applied in the presence of a complete fertilizer, lime depressed the yields in many experiments and its average effect was practically null. apparently, the rate of application, of a 4 metric tons per hectare, was excessive for the soils studied, which were low in clay and organic matter. while the 1960-61 average yield of the treatments without phosphorus and nitrogen corresponded to 444 kg/ha, that of the treatments which received 30 kg/ha of n as ammonium sulfate and 120 kg/ha of p2o5 as ordinary superphosphate increased to 1,307 kg/ha.
O empobrecimento causado pela eros?o e pela cultura algodoeira no solo do arenito Bauru
Grohmann, F.;Catani, R. A.;
Bragantia , 1949, DOI: 10.1590/S0006-87051949000200003
Abstract: the empovrishment of the soil brought about by erosion and cultivation of cotton has been studied in experimental plots where catch tanks were employed to collect soil removed by erosion. these tests have been carried out by the soil conservation department at the experiment station of the instituto agron?mico of campinas, in pindorama, and on the "arenito bauru" soil type representative of the region. actually sixty percent of all coffee and eighty percent of all cotton cultivation in the state of s?o paulo is on the "arenito bauru" soil type. thus the data collected, although preliminary, are of great interest, and indicate that the empovrishment of the "arenito bauru" soil by erosion is extremely rapid. it is also pointed out that the "arenito bauru" soils are the most highly erodable of all soil types in the state of s?o paulo. a chemical analysis was made of representative samples of the original soils in the experimental plots and of samples of soil carried in the runoff, for the purpose of determining the losses due to erosion. it has been determined that the soil transported in the runoff is proportionally very much richer in mineral elements than was the original soil. the data obtained from analysis of samples showed that soil eroded from the experimental plots contained 2.0 times as much organic material, 2.8 times as much p2o5 ; 2.3 times as much k2o, and 1.9 times as much cao, as was determined present in the samples obtained from the original soil of the experimental plots. in the runoff water it has determined that calcium was present in larger quantities than other elements. on the basis of data obtained from the experimental plots with cotton cultivation, an evaluation and comparison was made of the amount of mineral elements lost by erosion and the amount used by the cotton crop. it was found that the empovrishment of the soil by loss of organic material and chemical elements was due more to erosion than to utilization of these in the production of
Lixivia??o do B. H. C. (is?mero gama) em solo tipo arenito Bauru
Gargantini, H.;Giannotti, O.;Tella, Romeu de;
Bragantia , 1957, DOI: 10.1590/S0006-87051957000100006
Abstract: this paper presents results from an experiment to study the leaching of the b. h. c. in a type of soil named "arenito bauru". the b. h. c. was put in a monolythic lysimeter of undisturbed structure which received measured amounts of distilled water. the whole percolate was analysed in its contents of b. h. c. later on the lysimeters were opened and the soil was analysed in different depths. the results obtained showed that the b. h. c. (isomerous gama) was not leached under the conditions of the experiment; 90 per cent of the total b. h. c. was retained in the upper 10 cm of the soil.
Canteras taller de basalto en la zona de Bajo Caracoles - río Olnie (Provincia de Santa Cruz)
Belardi,Juan Bautista; Carballo Marina,Flavia;
Intersecciones en antropolog?-a , 2005,
Abstract: basalt secondary quarries were surveyed in the zone of bajo caracoles, olnie river (nw of santa cruz), enabling a proposed extension of the regional availability radius of good and very good quality rocks for flint knapping. the interpretation of petrographic thin sections increases the existing petrographic variability within the archaeological and macrocospic denomination of basalto posadas.
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