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Sample records for fluvic neosoil compactacao

  1. Soil compaction: alterations in physical, chemical and biological attributes in a fluvic neosoil; Compactacao do solo: alteracoes nos atributos fisicos, quimicos e biologicos de um neossolo fluvico

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Eliane Ferreira

    2004-12-15

    The efficient management of soil proposes the correct utilization of agricultural practices to minimize the loss of structure, compaction, and nutrient losses in the soil, which are the main causes of its degradation. Such concerns reside in the fact that the impact from compaction can also be related to the soil capacity for losing carbon. This effect has strong influence on CO{sub 2} emissions to the atmosphere. On the other hand, induced mutation, a valuable tool for the development of genetic materials, that is tolerant to environmental adversities, can be helpful in the adaptation of crops in compacted soils. This study was conducted to evaluate isolated and combined effects of compaction, water content and organic amendments in soil respiration. Also it investigates the development of cowpea (V. unguiculata, L. Walp] var. IPA 206, in a Fluvic Neosoil, artificially compacted, with different fertilizer materials added (cowdung, NPK, organomineral I, and organomineral II). Also it evaluates the development of cowpea when the seeds were submitted to gamma irradiation ({sup 60}Co) and cultivated in compacted and non compacted soil, under greenhouse conditions, for 60 days. The isolated addition of spent coffee powder and marine algae to the soil increased the CO{sub 2} evolution from soil, reflecting variations in dynamics of the heterotrophic soil microbiota. CO{sub 2} evolution decreased with the increase in soil density, showing reductions in aeration. The values presented were found to be low in the treatment without addition of these materials (control) and showed them to be significantly increased in the treatments that received such residues, all over the incubation period. Plant height, root length, shoot dry matter production and dry matter of nodules diminished with the increase in soil density. The incorporation of the organomineral mixtures I and II to the artificially compacted soil, showed an increase in plant height, and root length, suggesting the

  2. Soil compaction: alterations in physical, chemical and biological attributes in a fluvic neosoil

    International Nuclear Information System (INIS)

    Viana, Eliane Ferreira

    2004-12-01

    The efficient management of soil proposes the correct utilization of agricultural practices to minimize the loss of structure, compaction, and nutrient losses in the soil, which are the main causes of its degradation. Such concerns reside in the fact that the impact from compaction can also be related to the soil capacity for losing carbon. This effect has strong influence on CO 2 emissions to the atmosphere. On the other hand, induced mutation, a valuable tool for the development of genetic materials, that is tolerant to environmental adversities, can be helpful in the adaptation of crops in compacted soils. This study was conducted to evaluate isolated and combined effects of compaction, water content and organic amendments in soil respiration. Also it investigates the development of cowpea (V. unguiculata, L. Walp] var. IPA 206, in a Fluvic Neosoil, artificially compacted, with different fertilizer materials added (cowdung, NPK, organomineral I, and organomineral II). Also it evaluates the development of cowpea when the seeds were submitted to gamma irradiation ( 60 Co) and cultivated in compacted and non compacted soil, under greenhouse conditions, for 60 days. The isolated addition of spent coffee powder and marine algae to the soil increased the CO 2 evolution from soil, reflecting variations in dynamics of the heterotrophic soil microbiota. CO 2 evolution decreased with the increase in soil density, showing reductions in aeration. The values presented were found to be low in the treatment without addition of these materials (control) and showed them to be significantly increased in the treatments that received such residues, all over the incubation period. Plant height, root length, shoot dry matter production and dry matter of nodules diminished with the increase in soil density. The incorporation of the organomineral mixtures I and II to the artificially compacted soil, showed an increase in plant height, and root length, suggesting the beneficial action

  3. PRODUCTION AND PHYSIOLOGICAL QUALITY OF SOYBEAN SEEDS IN ORTHIC QUARTZARENIC NEOSOIL OF THE CERRADO REGION

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    CHARLINE ZARATIN ALVES

    2015-01-01

    Full Text Available The aim of this study was to evaluate the effect of the sowing periods in production , productivity component and physiological quality of seeds of three soybean cultivars (TMG133RR, P98Y70RR and NS7670RR in Orthic Quartzarenic Neosoil in the cerrado region. The design used was a randomized block a factorial scheme design with four repetitions, and each plot with useful space consisted of three rows of four meters length, spaced at 0.45 meters. Field evaluations were the final stand, the height of the plants, height of the first pod insertion, the mass of 100 seeds and productivity. Already in the lab seeds were evaluated for germination and vigor (first germination count, emergency, emergence speed index, length and dry mass of the aerial part of the plant and roots, electrical conductivity, accelerated aging and tetrazolium test. It concludes that it is possible to use Orthic Quartzarenic Neosoils , located in the Cerrado region at altitudes higher than 600 m, in years and places with good water distribution in the spring - summer seasons, for grain and soybeans production, but as a first goal, the crop should be sown in the first 20 days of November otherwise it should take place in early December.

  4. Water allocations and mulching in castor bean crops in a semiarid Fluvic Neossol

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    Júlio José do Nascimento Silva

    Full Text Available The influence of different irrigation levels, both with and without mulching, was evaluated for the growth variables of productivity, production components and water use efficiency, in a castor bean crop (Ricinus Comunnis cv. BRS Energia, in a Fluvic Neossol of the semiarid in the Brazilian state of Pernambuco. The experimental design used was completely randomised in a factorial of 4 (irrigation levels × 2 (with and without mulch, with four replications. The irrigation levels were based on the evapotranspiration of the crop (ETc, with L1 = 60% ETc, L2 = 80% ETc, L3 = 100% ETc and L4 = 120% ETc. All growth variables showed significant differences to the mulch at 120 days after germination. The number of racemes per plant, percentage of bark, and water use efficiency responded significantly to the presence of mulch on the ground, while length of racemes, fruit yield and berry yield responded significantly to the isolated effects of the irrigation levels and ground cover. Levels L3 and L4 improved the performance of the crop, with an average productivity of over 2,360 kg berries ha-1.

  5. Humic and fluvic acids and organic colloidal materials in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Gaffney, J.S.; Marley, N.A. [Argonne National Lab., IL (United States); Clark, S.B. [Univ. of Georgia, Aiken, SC (United States)

    1996-04-01

    Humic substances are ubiquitous in the environment, occurring in all soils, waters, and sediments of the ecosphere. Humic substances arise from the decomposition of plant and animal tissues yet are more stable than their precursors. Their size, molecular weight, elemental composition, structure, and the number and position of functional groups vary, depending on the origin and age of the material. Humic and fulvic substances have been studied extensively for more than 200 years; however, much remains unknown regarding their structure and properties. Humic substances are those organic compounds found in the environment that cannot be classified as any other chemical class of compounds. They are traditionally defined according to their solubilities. Fulvic acids are those organic materials that are soluble in water at all pH values. Humic acids are those materials that are insoluble at acidic pH values (pH < 2) but are soluble at higher pH values. Humin is the fraction of natural organic materials that is insoluble in water at all pH values. These definitions reflect the traditional methods for separating the different fractions from the original mixture. The humic content of soils varies from 0 to almost 10%. In surface waters, the humic content, expressed as dissolved organic carbon (DOC), varies from 0.1 to 50 ppm in dark-water swamps. In ocean waters, the DOC varies from 0.5 to 1.2 ppm at the surface, and the DOC in samples from deep groundwaters varies from 0.1 to 10 ppm. In addition, about 10% of the DOC in surface waters is found in suspended matter, either as organic or organically coated inorganic particulates. Humic materials function as surfactants, with the ability to bind both hydrophobic and hydrophyllic materials, making numic and fluvic materials effective agents in transporting both organic and inorganic contaminants in the environment.

  6. Soil compaction and gamma radiation ({sup 60}Co) in the development of the cowpea beans [Vigna unguiculata, (L) Walp]; Compactacao do solo e radiacao gama ({sup 60}Co) no desenvolvimento do feijao caupi [Vigna unguiculata, (L) Walp

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Eliane Ferreira; Colaco, Waldeciro [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Radioagronomia]. E-mails: aroucha@ufpe.br; wcolaco@ufpe.br

    2005-08-15

    The objective is to investigate the effect of compaction and increased doses of gamma radiation on the development of cowpea [Vigna unguiculata, (L) Walp] var. IPA-206 cultivated in a Neossolo fluvic soil, artificially compacted. Significant differences were observed in plant height, with the increase doses in soil density (1.30 Mg.m{sup -3} - compacted soil and 1.70 Mg.m{sup -3} - non-compacted soil), and in response to increased doses of irradiation (y-rays) [ [0, 100, 200 and 300 Gy). The diameter of the stem was significantly reduced in response to the increase in soil density, however the same did not occur in relation to the doses of irradiation (y-rays) holding capacity of the soil was reduced in response to the increase in soil density. (author)

  7. Alterações químicas de um Neossolo Flúvico irrigado com águas salinas Chemical changes of a Fluvic Neossol cultivated with tomato and irrigated with saline water

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    Israel Venismare Cordeiro Gonçalves

    2011-09-01

    Full Text Available Com o objetivo de avaliar as alterações químicas de um Neossolo Flúvico do semiárido de Pernambuco cultivado com três cultivares de tomateiro e irrigado com água de dois valores de relação de adsorção de sódio (RAS e seis de condutividade elétrica (CE foi realizado um experimento em vasos de polietileno em delineamento em blocos ao acaso com arranjo fatorial 3 x 6 x 2 (três cultivares de tomateiro, seis valores de CE e dois de RAS e quatro repetições. Os atributos estudados foram: CE, pH e RAS do extrato de saturação do solo, Ca2+, Mg2+, K+ e Na+ solúveis em função dos cultivares e da CE e RAS da água de irrigação. Os cultivares de tomateiro estudados não alteraram os atributos CE, pH, RAS, Ca2+, Mg2+ e Na+ do extrato de saturação do solo. O aumento da salinidade da água de irrigação incrementou a CE do extrato de saturação e os teores de Ca2+, Na+, Mg2+ e K+. A água com RAS de 20 (mmol L-10,5 promoveu aumento da RAS do extrato de saturação do solo.Aiming to evaluate chemical changes of a Fluvic Neossol from Pernambuco's semiarid there were cultivated tree tomato cultivars, irrigated with saline water with two values of sodium adsorption ratio (SAR and six values of electrical conductivity (EC. The experiment was carried out in polyethylene pots in randomized blocks design with factorial arrangement 3 x 6 x 2 (three tomato cultivars, six values of EC and two SAR and four replications. The variables studied were: EC, pH, SAR, Ca2+, Mg2+, K+ e Na+ of the saturation extract of soil depending on the cultivar and the EC and SAR of irrigation water. The tomato cultivars used in this study did not promote significant changes in the EC, pH, SAR, Ca2+, Mg2+ e Na+ of saturation extracts of soil. Increasing salinity of irrigation water promotes increases in the EC, Ca2+, Na+, Mg2+ and K+ of saturation extract of soil. Water with SAR of 20 (mmol L-10,5 increased the SAR value of the soil saturation extract.

  8. MINERALOGIA E QUÍMICA DE SOLO DE VÁRZEA E SUAS SUSCEPTIBILIDADES NO PROCESSO DE TERRAS CAÍDAS NA COMUNIDADE DO DIVINO ESPÍRITO SANTO-AM / Mineralogy and chemistry of the lowland soil and its sensibilities in the process of lands falls in community Divino Espírito Santo (Amazonas, Brazil.

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    Regiane Campos Magalhães

    2013-12-01

    Full Text Available The study about the mineralogical and chemical lowland soils generate information to compose a current survey about the susceptibility of lowland soil to process Fallen Lands. With this purpose we studied five profiles the banks of the Solimões River, located in the municipality of Iranduba (AM. The information obtained allowed to determine the Neosoil Fluvic the study area has favorable conditions for cultivation with an average pH of 6.2, with high levels of Ca, Mg, K, P, micronutrients and zero Al content, with high levels of C and M. O. in the first layer and a decrease in depth. Thus, Neosoil Fluvic was characterized as Tb eutrophic, with base saturation above 50%, with good CTC. The mineralogy was homogeneous in all profiles, with a predominance of primary minerals: Quartz, Albite and rutile, with low proportions of clay minerals Muscovite, Kaolinite, Muscovite-Illite interstratified and Illite.

  9. Níveis de silicato de cálcio e magnésio na produção das gramídeas Marandu e Tanzânia cultivadas em um Neossolo Quartzarênico Level of calcium and magnesium silicate in the yield of Marandu grass and Tanzania grass cultivated in one Quartzsandy Neosoil

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    Caio Augustus Fortes

    2008-02-01

    Full Text Available O estudo foi conduzido em casa-de-vegetação do Departamento de Ciência do Solo da Universidade Federal de Lavras, Lavras-MG, com o objetivo de avaliar o efeito da correção da acidez do solo, por meio da aplicação de níveis de silicato de Ca e Mg, na produção das gramíneas Brachiaria brizantha cv. Marandu e Panicum maximum cv. Tanzânia-1 cultivadas em solo Neossolo Quartzarênico ortic. O delineamento experimental utilizado foi blocos ao acaso, em esquema fatorial 2 x 5 com quatro repetições, sendo duas forrageiras e cinco níveis de saturação por bases (V% original, 40, 60, 80 e 100%. Cada unidade experimental correspondeu a um vaso sem furos, com capacidade para 4,0 dm³ de solo, totalizando 40 vasos. Foram avaliadas as produções de MS por corte (PMS e total (PTMS, a altura e o número de perfilhos. Não houve variação entre as gramíneas em altura de perfilhos. O Tanzânia foi superior ao Marandu em PMS e número de perfilhos. Houve aumento linear na PMS, PTMS e altura de perfilhos. Conclui-se que ambas as gramíneas responderam de forma positiva à elevação dos níveis de V%, em PMS, até 54,8%. O Tanzânia produziu mais MS em relação ao Marandu.This study was conducted in a greenhouse of the Soil Science Department at Universidade Federal de Lavras, Lavras-MG, with the purpose of evaluating the effect of the soil correction acidity, by the application of Ca and Mg silicate levels, in the production of grasses Brachiaria brizantha cv. Marandu and Panicum maximum cv. Tanzânia-1 cultivated in Quartzsandy Neosoil ortic. The experimental design was a randomized complete block, in 2 x 5 factorial scheme with four replicates, being two forages and five levels of base saturation (BS%; (original BS, 40, 60, 80 and 100%. Each experimental unit corresponded to a pot with a capacity of 4.0 dm³ of soil, totalizing 40 pots. The dry matter yield (DMY for cut and total (TDMY, height and number of tillers were evaluated. There were

  10. A spatial application of a vegetation productivity equation for neo-soil reconstruction

    International Nuclear Information System (INIS)

    Burley, J.B.

    1999-01-01

    Reclamation specialists are interested in the application of recently developed soil productivity equations for post-mining reclamation planning and design. This paper presents the application of one recently developed soil productivity equation to a surface coal mine site in Mercer County, North Dakota. Geographic information systems (GIS) technology (Map*Factory 1.1) was combined with a soil productivity equation developed by the author to generate a GIS script to calculate a site's pre-mining productivity per 10 meter grid cell and then summed to calculate the grand and the expected average soil productivity for the site, resulting in a pre-mining baseline numerical spatial scores. Several post-mining alternatives were evaluated to study various soil management strategies to restore post-mining soil productivity, including: an abandoned mine landscape treatment, a reconstructed topsoil treatment with graded gentile slopes, and a reconstructed topsoil treatment with soil improvements. The results indicated that the abandoned mine scenario was significantly different than the other three treatments (ple0.05), with the reconstructed topsoil treatment with soil amendments generating the greatest estimated productivity

  11. Errata to: Characteristics of humic acid fluvic acids in Arabian Sea sediments

    Digital Repository Service at National Institute of Oceanography (India)

    Sardessai, S.

    stream_size 1 stream_content_type text/plain stream_name Indian_J_Mar_Sci_24_245.pdf.txt stream_source_info Indian_J_Mar_Sci_24_245.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  12. Obtention of charcoal briquettes from rice husks using low compaction pressure; Obtencao de briquetes de carvao vegetal de cascas de arroz utilizando baixa pressao de compactacao

    Energy Technology Data Exchange (ETDEWEB)

    Morais, Marcia R.; Seye, Omar; Freitas, Katrina T. de; Rodrigues, Monica; Santos, Eyde C.S. dos; Souza, Rubem C.R. [Universidade Federal do Amazonas (CDEAM/UFAM), Manaus, AM (Brazil). Centro de Desenvolvimento Energetico Amazonico

    2006-07-01

    This work consists of the preparation of briquette from carbonized rice's husks in low pressure. The results demonstrate are necessary a fine granulation of the rice's husks coal to obtainment of briquettes. The ultimate analysis of the briquette did not detect the presence of nitrogen and sulfur, and that prevents the formation and emission of acid gases that can produce corrosion in the equipment and pollute the atmosphere. The performance of the briquette production was superior to 80%. The briquettes present high heating value (HHV) 17,73 MJ/kg and adequate mechanic resistance for the use in gasifier-engine system. (author)

  13. Application of portable nuclear gauge to the control of soil, asphalt and concrete compaction; A aplicacao dos medidores nucleares portateis no controle de compactacao de solos, asfalto e concreto

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    Castro, Bruno Almeida Cunha de [PATTROL, Pavimentos, Tracados e Obras Ltda. (Brazil)

    1999-07-01

    This paper presents an overview on the density and humidity determination methodology by using nuclear techniques, describing the different process phases and demonstrating their advantages compared to the traditional methods.

  14. Influência de doses de fósforo no fluxo difusivo em solos de Alagoas Influence of phosphorus doses in diffusive flow in the soils of Alagoas

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    Adelmo L. Bastos

    2008-04-01

    Full Text Available Objetivando avaliar o efeito de diferentes doses de fósforo sobre o fluxo difusivo deste elemento em amostras de solos do Estado de Alagoas, conduziu-se um experimento em laboratório, no Centro de Ciências Agrárias da Universidade Federal de Alagoas, município de Rio Largo, AL. Os solos utilizados foram classificados como Latossolo Amarelo coeso (LAx, Argissolo Acinzentado (PAC, Neossolo Flúvico (RU, Neossolo Quartzarênico RQ, Luvissolo Crômico órtico (TCo e Luvissolo Crômico pálico (TCp. Realizaram-se análises químicas, físicas e mineralógicas. O P remanescente foi determinado na solução de equilíbrio e a CMAP o foi em função do fósforo remanescente, utilizando-se, como unidades experimentais, anéis de PVC, que serviram como câmara de difusão. As doses de fósforo corresponderam a 0, 10, 20 e 30% da CMAP. Para avaliação do fluxo difusivo de fósforo dos solos, se utilizaram papel de troca aniônica e a metodologia de papel-filtro impregnado com óxido de ferro. O ensaio consistiu em um arranjo fatorial (6 x 4 correspondendo, respectivamente, a seis solos e quatro doses de fósforo. Os solos mais arenosos (RQ e RU e a maior dose usada indicaram sempre os maiores fluxos difusivos de fósforo.The effect of distinct doses of phosphorus was evaluated on the diffusion of this element in soil samples from the State of Alagoas. The experiment was performed in the laboratory of the Centro de Ciências Agrárias of the Federal University of Alagoas, Rio Largo, AL. The soils were classified as a compacted Yellow Latossol, Grey Argissoil, Fluvic Neosoil, Quartzanic Neossoil and ortic Chromic Luvissoil. Chemical, physical and mineralogical analyses had been made. The determination of the remaining P was made in the equilibrium solution. The maximum capacity of adsorption was determined through the remaining phosphorus, using PVC rings which were used as diffusion chambers. The doses of phosphorus had been equivalent to 0, 10, 20

  15. Formas de potássio em solos de várzea e sua disponibilidade para o feijoeiro Potassium forms in lowland soils and availability to common bean

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    M. R. Villa

    2004-08-01

    Full Text Available O presente estudo teve como objetivos caracterizar as formas de K em solos de várzea e o aproveitamento dessas formas pela planta, avaliar a resposta do feijoeiro à aplicação desse nutriente nesses solos e determinar os seus níveis críticos nos solos e nas plantas. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 4 x 5, com quatro repetições, sendo quatro solos de várzea [Gleissolo Melânico (GM, Gleissolo Háplico (GX, Neossolo Flúvico (RU e Organossolo Méssico (OY] e cinco níveis de saturação por K da CTC potencial (natural, 4, 6, 8 e 10 %. Foram cultivadas quatro plantas de feijoeiro (Phaseolus vulgaris L. por vaso até a produção de grãos. Amostras dos solos foram coletadas para a determinação do K total, não-trocável, trocável, em solução, disponível pelos extratores Mehlich-1 e Resina e medidas da relação Quantidade/Intensidade de K. Os teores de K total e K não-trocável foram maiores nos solos OY e RU, enquanto os teores de K trocável e K em solução foram maiores nos solos OY e GM. As saturações críticas por K da CTC potencial foram de 5,0, 4,1, 8,7 e 5,3 %, enquanto os níveis críticos de K foliar foram de 17,9, 30,5, 16,8 e 14,6 mg kg-1, para os solos OY, GM, GX e RU, respectivamente.The present study had as objectives to characterize K forms, plant use of these forms and to evaluate the common bean (Phaseolus vulgaris L. response to K application in four lowland soils. It was also sought to determine the critical levels for K in soils and plant. The experimental design was completely randomized in a 4 x 5 factorial scheme with four replications. The treatments were a combination of four lowland soils [Mesic Organosoil (OY, Melanic Gleysoil (GM, Haplic Gleysoil (GX, and Fluvic Neosoil (RU] and five K CEC saturation levels (native, 4, 6, 8, and 10 %. Four bean plants per pot were cultivated until grain production. Soil samples were analyzed for total K, non

  16. Sintering of nanopowders of ZrO{sub 2} (Y{sub 2}O{sub 3}): Effect of compaction pressure on densification; Sinterizacao de pos nanoparticulados de ZrO{sub 2} (Y{sub 2}O{sub 3}): efeito da pressao de compactacao na densificacao

    Energy Technology Data Exchange (ETDEWEB)

    Palmeira, Alexandre Alvarenga; Magnago, Roberto de Oliveira; Pereira, Glayce Cassaro [Centro Universitario de Volta Redonda (UNIFOA), Volta Redonda, RJ (Brazil); Bondioli, Marcelo Jose; Strecker, Kurt [Universidade Federal Sao Joao Del-Rey (UFSJ), MG (Brazil); Santos, Claudinei dos [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil)

    2014-06-15

    In this work studied the powders (nano) sintered of ZrO{sub 2} (Y{sub 2}O{sub 3}) by dilatometry. Was identified the effect of compaction pressure variation in the final results of densification of materials. Powders were compacted at different compaction pressures. The compacts were subjected to temperatures of 1250°C to 1400°C with sintering levels ranging from 0 to 8 hours. Samples were characterized by X-ray diffraction and relative density using Archimedes method. The results were compared with powders (micro) of similar composition in order to compare the effect of particle size on densification parameters. The samples were further subjected to microstructural characterization in order to identify the average grain size of the sintering under each condition used in both materials. (author)

  17. Effects on the work of a direct ethanol fuel cell as function of compacting force applied to the cell; Efeitos no funcionamento de uma celula a combustivel com alimentacao direta de etanol (CCADE) em funcao da forca de compactacao aplicada a celula

    Energy Technology Data Exchange (ETDEWEB)

    Belchior, P.M.; Forte, M.M.C. [UFRGS - Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Serafin, R.; Fusiger, V.; Carpenter, D. [FURB - Fundacao Universidade Regional de Blumenau, SC (Brazil)

    2010-07-01

    This experiment aimed to verify the influence due to the variation of the compacting force applied to a DEFC. According to the tests, as the increase of cell compacting, the performance improves significantly. According applied tests, when the high electrical conductivity components are used, small differences of the cell compacting can generate a large difference on the total ohmic resistance. Through the tests one can conclude that with the increase of cell compacting, the contact probably increase among the distribution of reagents and the diffuser layer, improving the cell performance. (author)

  18. ESTABELECIMENTO A CAMPO DE MUDAS DE Eucalyptus grandis MICORRIZADAS COM Pisolithus microcarpus (UFSC Pt 116 EM SOLO ARENOSO

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    Andréa Hentz de Mello

    2009-01-01

    Full Text Available The aim of this work was to evaluate the survival and the initial growth of mycorrhizated eucalypts with Pisolithus microcarpus (UFSC Pt 116 ectomycorrhizal fungus, after its transplant to area subject to the arenization process in São Francisco de Assis, RS. The area was divided into four blocks, each one with four treatments (fertile turf with and without mycorrhizae, Quartzarenic Neosoil with and without mycorrhizae. Each parcel was composed of 16 seedlings arranged in four lines in the spacing of 1,5 m x 1,5 m, totalizing in each block 64 seedlings. 90 days after the planting in the field, the eucaliptus seedlings produced in turf with fungus in the fertile substratum presented a survival rate of 100 %, whereas for those produced in fertile turf without fingi, the survival rate was 92 %. The seedlings produced in the Quartzarenic Neosoil with and without mycorrhizae had a survival rate varying around 98 and 89 %, respectively. The produced seedlings with turf and fungus showed significant differences in height and stem diameter. This study showed that the Eucalyptus grandis seedlings produced in substratum fertile turf and inoculated with the Pisolithus microcarpus (UFSC Pt 116 isolated may maintain good development and establishment in the field.

  19. Sound Wave Energy Resulting from the Impact of Water Drops on the Soil Surface.

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    Magdalena Ryżak

    Full Text Available The splashing of water drops on a soil surface is the first step of water erosion. There have been many investigations into splashing-most are based on recording and analysing images taken with high-speed cameras, or measuring the mass of the soil moved by splashing. Here, we present a new aspect of the splash phenomenon's characterization the measurement of the sound pressure level and the sound energy of the wave that propagates in the air. The measurements were carried out for 10 consecutive water drop impacts on the soil surface. Three soils were tested (Endogleyic Umbrisol, Fluvic Endogleyic Cambisol and Haplic Chernozem with four initial moisture levels (pressure heads: 0.1 kPa, 1 kPa, 3.16 kPa and 16 kPa. We found that the values of the sound pressure and sound wave energy were dependent on the particle size distribution of the soil, less dependent on the initial pressure head, and practically the same for subsequent water drops (from the first to the tenth drop. The highest sound pressure level (and the greatest variability was for Endogleyic Umbrisol, which had the highest sand fraction content. The sound pressure for this soil increased from 29 dB to 42 dB with the next incidence of drops falling on the sample The smallest (and the lowest variability was for Fluvic Endogleyic Cambisol which had the highest clay fraction. For all experiments the sound pressure level ranged from ~27 to ~42 dB and the energy emitted in the form of sound waves was within the range of 0.14 μJ to 5.26 μJ. This was from 0.03 to 1.07% of the energy of the incident drops.

  20. Sound Wave Energy Resulting from the Impact of Water Drops on the Soil Surface.

    Science.gov (United States)

    Ryżak, Magdalena; Bieganowski, Andrzej; Korbiel, Tomasz

    2016-01-01

    The splashing of water drops on a soil surface is the first step of water erosion. There have been many investigations into splashing-most are based on recording and analysing images taken with high-speed cameras, or measuring the mass of the soil moved by splashing. Here, we present a new aspect of the splash phenomenon's characterization the measurement of the sound pressure level and the sound energy of the wave that propagates in the air. The measurements were carried out for 10 consecutive water drop impacts on the soil surface. Three soils were tested (Endogleyic Umbrisol, Fluvic Endogleyic Cambisol and Haplic Chernozem) with four initial moisture levels (pressure heads: 0.1 kPa, 1 kPa, 3.16 kPa and 16 kPa). We found that the values of the sound pressure and sound wave energy were dependent on the particle size distribution of the soil, less dependent on the initial pressure head, and practically the same for subsequent water drops (from the first to the tenth drop). The highest sound pressure level (and the greatest variability) was for Endogleyic Umbrisol, which had the highest sand fraction content. The sound pressure for this soil increased from 29 dB to 42 dB with the next incidence of drops falling on the sample The smallest (and the lowest variability) was for Fluvic Endogleyic Cambisol which had the highest clay fraction. For all experiments the sound pressure level ranged from ~27 to ~42 dB and the energy emitted in the form of sound waves was within the range of 0.14 μJ to 5.26 μJ. This was from 0.03 to 1.07% of the energy of the incident drops.

  1. ESTRUTURA E DIVERSIDADE DA COMUNIDADE ARBÓREA DE UMA FLORESTA SUPEROMONTANA, NO PLANALTO DE POÇOS DE CALDAS (MG

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    Malcon do Prado Costa

    2011-01-01

    Full Text Available A survey of the tree community of a ombrophilous upper montane forest, situated in Poços de Caldas, Brazil (1200-1575 m of altitude; 21°46'25"S, 46'24"10"W was carried out in order to assess its environmental and structural variation. The physiognomic (density, basal area and distribution of size of the trees and community structure (composition, distribution and diversity of species were analyzed through 22 plots of 5 x 100 m, where the tree individuals with diameter at breast height ¿ 5 cm were sampled. The topographic variables were measured and the surface soil samples were collected to obtain their chemical and texture attributes. The survey resulted in 53 botanic families, 104 genera, 178 species and 1963 individuals, as well as four soil classes: distrofic and eutrofic Argisoil, Cambisoil and Litolic Neosoil, distributed sequentially from the hilltop to the base of the fragment. The canonic correspondence analyses showed a gradient of tree species distribution mainly correlated with variations of quotas, magnesium content (Mg++ and aluminum saturation (m.

  2. Radiation decomposition of humic substances in landfill disposal leachate

    International Nuclear Information System (INIS)

    Sawai, Takeshi; Sawai, Teruko; Shimokawa, Toshinari

    1979-01-01

    The leachate generated from landfill contains humic substances such as humic acid and fluvic acid. It shows, in general, high chemical oxygen demand (COD) and biological oxygen demand (BOD), and colors in dark brown. When the leachate collected on the No. 15 landfill in Tokyo Bay was irradiated by γ-rays from a 60 Co source in bubbling air, the total organic carbon (TOC) decreased with increasing dose and the brown color was bleached. The effects of pH, flow rate, and dose rate on the decrease of TOC, the variations of UV spectrum, and the formation of carbon dioxide by the irradiation were examined. The decreasing rate of TOC increased with an increase of the flow rate up to -- 11/min and showed a maximum value in the region of pH 4 - 6. It was also dependent on the dose rate and increased with a decrease of the dose rate. The radiation chemical yield, G(-TOC), reached 162 at low dose rate of 1.3 x 10 4 rad/h. This result suggests that a radiation-induced chain reaction occurred. The amount of TOC decreased was almost equal to that of carbon dioxide formed. This result shows that the organic substances were decomposed by irradiation to carbon dioxide as a final product and it was ejected from the solution. (author)

  3. Insights into the redox components of dissolved organic matters during stabilization process.

    Science.gov (United States)

    Yuan, Ying; Xi, Bei-Dou; He, Xiao-Song; Ma, Yan; Zhang, Hui; Li, Dan; Zhao, Xin-Yu

    2018-05-01

    The changes of dissolved organic matter (DOM) components during stabilization process play significant effects on its redox properties but are little reported. Composting is a stabilization process of DOM, during which both the components and electron transfer capacities (ETCs) of DOM change. The redox components within compost-derived DOM during the stabilization process are investigated in this study. The results show that compost-derived DOM contained protein-like, fulvic-like, and humic-like components. The protein-like component decreases during composting, whereas the fulvic- and humic-like components increase during the process. The electron-donating capacity (EDC), electron-accepting capacity (EAC), and ETC of compost-derived DOM all increase during composting but their correlations with the components presented significant difference. The humic-like components were the main functional component responsible for both EDC and ETC, whereas the protein- and fluvic-like components show negative effects with the EAC, EDC, and ETC, suggesting that the components within DOM have specific redox properties during the stabilization process. These findings are very meaningful for better understanding the geochemical behaviors of DOM in the environment.

  4. Growth, biomass production and ions accumulation in Atriplex nummularia Lindl grown under abiotic stress

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    Hidelblandi F. de Melo

    2016-02-01

    Full Text Available ABSTRACT Atriplex nummularia is a halophyte of great importance in the recovery of saline soils and is considered as a model plant to study biosaline scenarios. This study aimed to evaluate biometric parameters, biomass production and the accumulation of ions in A. nummularia grown under abiotic stresses. Cultivation was carried out in a Fluvic Neosol for 100 days, adopting two water regimes: 37 and 70% of field capacity. Plants were irrigated with saline solutions containing two types of salts (NaCl and a mixture of NaCl, KCl, MgCl2 and CaCl2 at six levels of electrical conductivity: 0, 5, 10, 20, 30 and 40 dS m-1, arranged in a 6 x 2 x 2 factorial with 4 replicates, forming 96 plots. At the end of the experiment, plants were divided into leaves, stem and roots, for the determination of fresh matter (FM, dry matter (DM and estimated leaf area (LA, besides the contents of Ca2+, Mg2+, Na+, K+ and Cl-. The type of salt did not influence plant growth or biomass production; however, it influenced the levels of Ca2+, Mg2+, Na+ and Cl- in the leaves and Mg2+, K+ and Cl- in the roots. Increase in salinity reduced the contents of Ca2+, Mg2+, Na+, K+ and Cl- for all treatments.

  5. Mechanical behaviour of AlSiC nano composites produced by ball milling and spark plasma sintering =

    Science.gov (United States)

    Buchheim, Claudia Sofia de Andrade Redondo Murilhas

    Neste trabalho foram produzidos nanocompositos de AlSiC misturando aluminio puro com nano particulas de SiC com diâmetro de 45 - 55 nm, usando, de forma sequencial, a tecnica da metalurgia do po e a compactacao por "Spark Plasma Sintering". O composito obtido apresentava graos com 100 nm de diâmetro, encontrandose as particulas de SiC localizadas, principalmente, nas fronteiras de grao. O nanocomposito sob a forma de provetes cilindricos foi submetido a testes de compressao uniaxial e a testes de nanoindentacao para analisar a influencia das nanoparticulas de SiC, da fracao volumica de acido estearico e do tempo de moagem, nas propriedades mecânicas do material. Para efeitos de comparacao, utilizouse o comportamento mecânico do Al puro processado em condicoes similares e da liga de aluminio AA1050O. A tensao limite de elasticidade do nanocomposito com 1% Vol./Vol. de SiC e dez vezes superior a do AA1050. O refinamento de grao a escala nano constitui o principal mecanismo de aumento de resistencia mecânica. Na realidade, o Al nanocristalino sem reforco de particulas de SiC, apresenta uma tensao limite de elasticidade sete vezes superior a da liga AA1050O. A adicao de 0,5 % Vol./Vol. e de 1 % Vol./Vol. de SiC conduzem, respetivamente, ao aumento da tensao limite de elasticidade em 47 % e 50%. O aumento do tempo de moagem e a adicao de acido estearico ao po durante a moagem conduzem apenas a um pequeno aumento da tensao de escoamento. A dureza do material medida atraves de testes de nanoindentacao confirmaram os dados anteriores. A estabilidade das microestruturas do aluminio puro e do nanocomposito AlSiC, foi testada atraves de recozimento de restauracao realizado as temperaturas de 150 °C e 250 °C durante 2 horas. Aparentemente, o tratamento termico nao influenciou as propriedades mecânicas dos materiais, excepto do nanocomposito com 1 % Vol./Vol. de SiC restaurado a temperatura de 250 °C, para o qual se observou uma reducao da tensao limite de elasticidade

  6. Aspectos florísticos da vegetação de restinga no litoral de Pernambuco Floristics aspects of restinga vegetation in the coast of Pernambuco - Brazil

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    Ana Cláudia Sacramento

    2007-12-01

    Full Text Available As zonas costeiras acolhem quadros de alta riqueza e relevância ecológica que as qualificam como importante ecossistema para conservação. O objetivo deste estudo foi listar as espécies que compõem a restinga da praia do Paiva e descrever a sua fisionomia. A área de restinga compreende 147 ha, situa-se no Município do Cabo de Santo Agostinho, PE, sob as coordenadas 08º07'30"S e 35º00'55"W. As coletas florísticas foram realizadas durante 28 meses, em todos os estratos. O solo foi classificado como Neossolo Quartzarênico; foram determinadas duas fisionomias: a floresta não-inundável e o fruticeto aberto não-inundável. Foram listadas 124 espécies, distribuídas em 103 gêneros e 55 famílias. As famílias com maior número de espécies foram Myrtaceae, com 11 espécies, Cyperaceae (10, Fabaceae (8, Euphorbiaceae (7, Rubiaceae (6 e Asteraceae (5. As espécies Anacardium occidentale, Tapirira guianensis, Chamaecrista ramosa, Protium heptaphyllum, Byrsonima sericea, Myrcia rotundifolia e Marlierea schotti são encontradas na maioria das restingas do Nordeste. No entanto, devido à incipiência dos estudos na Região não foram verificadas espécies endêmicas.The high biodiversity and richness of the coastal zone make it an important ecosystem to be preserved. The aim of this study is to list the species composition of the restinga area (147 ha. of Paiva beach, in Cabo de Santo Agostinho-Pernambuco (08º07'30"S and 35º00'55"W and describe the physiognomies. Floristic survey was carried out for 28 months for all strata. The soil was classified as Quartzarenic Neosoil and two physiognomies were determined: unflooded forest and unflooded open shrubby vegetation. One hundred-twenty-four species were recorded, distributed in 103 genera and 55 families. The families with the highest number of species were: Myrtaceae (11, Cyperaceae (10, Fabaceae (8, Euphorbiaceae (7, Rubiaceae (6 and Asteraceae (5. Anacardium occidentale, Byrsonima sericea

  7. Resposta do milho a doses de fósforo Response of corn to doses of phosphorus

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    Adelmo L. Bastos

    2010-05-01

    Full Text Available Conduziu-se um experimento em casadevegetação, do Centro de Ciências Agrárias da Universidade Federal de Alagoas, Rio Largo, AL, com o objetivo de avaliar o efeito de diferentes doses de P recomendadas pela capacidade máxima de adsorção de fósforo - CMAP (%, sobre os teores de P e matéria seca da cultura do milho, em solos de Alagoas. Os solos foram classificados como Latossolo Amarelo coeso, Argissolo Acinzentado, Neossolo Flúvico, Neossolo Quartzarênico, Luvissolo Crômico órtico e Luvissolo Crômico pálico. Retiraram-se subamostras para análises físicas, químicas e mineralógicas. O experimento foi arranjado em esquema fatorial (6 x 4 correspondendo a 6 solos e quatro doses de P (0, 10, 20 e 30% da CMAP, em delineamento em blocos casualizados. A determinação do P remanescente foi feita em solução de equilíbrio. A CMAP foi determinada através do fósforo remanescente. A massa de matéria seca da parte aérea da planta apresentou melhor resultado no Luvissolo Crômico pálico, com a dose de 10% da CMAP e o solo que proporcionou os maiores teores de fósforo na planta foi o Neossolo Flúvico na dose de 30% da CMAP.An experiment was conducted in a greenhouse of the Centro de Ciências Agrárias, Universidade Federal de Alagoas - Rio Largo/AL, aiming to evaluate the effect of different doses of P recommended by the maximum adsortion capacity of phosphorus - CMAP (%, on content of P and the production of mass of dry matter in corn. The soils were classified as cohesive Yellow Latosol, Gray Argisol, Fluvic Neosol, Quartzarenic Neosol, ortic Chromic Luvisol and palic Chromic Luvisol. Soil samples were taken for physical, chemical and mineralogical analyses. The experiment was arranged in a factorial design (6 x 4 corresponding to the 6 soils and the 4 doses of P (0, 10, 20 and 30% of the CMAP, in a randomized block design. The determination of the remenecent P was made in a equilibrium solution. The CMAP was determined through

  8. Teor de zinco, cádmio e chumbo em plantas de arroz em solos incubados com resíduo siderúrgico Contents of zinc, cadmium and lead in rice plants in soils incubated with slag

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    André F. M. de Andrade

    2010-10-01

    Full Text Available Os efeitos da aplicação de resíduo siderúrgico, proveniente da concentração de Zn em lama de altos fornos siderúrgicos, como fonte de Zn às plantas de arroz e a toxicidade de Cd e Pb no resíduo, foram avaliados em experimento. O material de solo usado proveio do horizonte superficial dos solos Latossolo Vermelho Amarelo (LVA; Neossolo Flúvico (RU e Argissolo Vermelho Amarelo (PVA, coletados no município de Pinheiral, Estado do Rio de Janeiro; utilizou se a variedade de arroz (Oryza sativa L. BRS Curinga. As plantas foram coletadas aos 145 dias após a semeadura; aquelas crescidas no Neossolo Flúvico apresentaram a maior produção de matéria seca e a maior acumulação de zinco, mas a menor de cádmio, enquanto as desenvolvidas no Argissolo Vermelho Amarelo indicaram a menor produção de matéria seca, menor acumulação de zinco, mas maior de chumbo e de cádmio. O extrator DTPA foi alvo de correlações elevadas e significativas com as concentrações de chumbo, cádmio e zinco, nas raízes e na parte aérea e, com a quantidade acumulada nas plantas, mostrando se bom indicador da biodisponibilidade desses três metais. Pelas características apresentadas nos solos estudados e pelas concentrações fitotóxicas do chumbo e do cádmio encontradas nas plantas desenvolvidas no PVA, não é recomendável a utilização desse resíduo como fonte de zinco para a cultura do arroz.The effects of the application of slag, from the concentration of Zn in the mud of steel slag, as a source of Zn for rice plants and the toxicity of Cd and Pb in the residue were studied in a greenhouse during the period from April 2005 to March 2006. The material used came from the surface horizon of a Red Yellow Oxisol (LVA; Fluvic Entisol (RU and Red Yellow ultisol (PVA, collected in the municipality of Pinheiral, in the State of Rio de Janeiro. The variety of rice (Oryza sativa L. BRS Joker was used. Plants were harvested at 145 days after sowing; those

  9. Availability of {sup 99}Tc in undisturbed soil cores

    Energy Technology Data Exchange (ETDEWEB)

    Denys, Sebastien; Echevarria, Guillaume E-mail: guillaume.echevarria@ensaia.inpl-nancy.fr; Florentin, Louis; Leclerc-Cessac, Elisabeth; Morel, Jean-Louis

    2003-07-01

    Models for safety assessment of radioactive waste repositories need accurate values of the soil-to-plant transfer of radionuclides. In oxidizing environments, {sup 99}Tc is expected to occur as pertechnetate ({sup 99}TcO{sub 4}{sup -}). Due to its high mobility, leaching of this element in the field might be important, potentially affecting the reliability of estimated transfer parameters of {sup 99}Tc as measured in closed experimental systems such as hydroponics or pot experiments. The aim of this experiment was to measure the leaching of {sup 99}Tc in undisturbed irrigated soil cores under cultivation as well as plant uptake and to study the possible competition between the two transfer pathways. Undisturbed soil cores (50x50 cm) were sampled from a Rendzic Leptosol (R), a colluvial Fluvic Cambisol (F) and a Dystric Cambisol (D) using PVC tubes (three cores sampled per soil type). Each core was equipped with a leachate collector at the bottom, allowing the monitoring of {sup 99}Tc leaching through the cores. Cores were placed in a greenhouse and maize (Zea mays L., cv. DEA, Pioneer[reg]) was sown. After 135 d, maize was harvested and radioactivity determined in both plant and water samples. Results showed that during the growing period, leaching of {sup 99}Tc was limited, due to the high evapotranspiration rate of maize. After harvest, leaching of {sup 99}Tc went on because of the absence of evapotranspiration. Effective uptake (EU) of {sup 99}Tc in leaves and grains was calculated. EU reached 70% of the input in the leaves and was not significantly different among soils. These results confirmed those obtained from pot experiments, even though leaching was allowed to occur in close-to-reality hydraulical conditions. As a consequence, it was concluded that pot experiments are an adequate surrogate for more complex 'close-to-reality' experimental systems for measuring transfer factors.

  10. Phyto extraction of 99Tc on soil cores with aged contamination

    International Nuclear Information System (INIS)

    Massoura, S.T.; Echevarria, G.; Morel, J.L.; Massoura, S.T.; Leclerc-Cessac, E.; Denys, D.

    2004-01-01

    99 Tc is an artificial radionuclide which is found in high-activity and long-lived nuclear waste. This work was designed to study the phyto-extraction of 99 Tc in soils that had received aged contamination and to monitor the resulting 99 Tc concentrations in the soil solution of undisturbed soil cores in a greenhouse. Undisturbed soil cores had been sampled previously from a Rendzic Leptosol (R), a Fluvic cambisol (F) and a Dystric cambisol (D), using 0.5-m diameter PVC tubing (3 samples/soil type) without disturbing soil structure (1). Each core was equipped with two nylon porous cups (respectively 20 and 35 cm deep) and a final leachate collector. A 99 TcNO 3 solution had been supplied at the soil surface of each core during the two previous years (4200 kBq in total) in which maize and wheat had been successively cropped. These two crops had already removed 30-65% of total contamination before the present study. After the second year no more 99 Tc was added to the cores. Thereafter, Lolium perenne was cultivated for 20 successive months. 99 Tc was determined in both plant aerial parts and water samples (from both cups and collectors), and the balance of 99 Tc in the system was established after phyto-extraction. Results showed that transfer of 99 Tc to plants vary among soils: 7% on soil R to 11% on soil D. Concentration of 99 Tc in the porous cups dramatically decreased in all soils. The plants maintained low and stable concentration levels of 99 Tc in the soil solution which decreased the potential migration of the radionuclide through the cores: The leaching of 99 Tc in the final collectors of the R soil cores decreased from 18 to 1.7 Bq mL -1 . (author)

  11. Availability of 99Tc in undisturbed soil cores

    International Nuclear Information System (INIS)

    Denys, Sebastien; Echevarria, Guillaume; Florentin, Louis; Leclerc-Cessac, Elisabeth; Morel, Jean-Louis

    2003-01-01

    Models for safety assessment of radioactive waste repositories need accurate values of the soil-to-plant transfer of radionuclides. In oxidizing environments, 99 Tc is expected to occur as pertechnetate ( 99 TcO 4 - ). Due to its high mobility, leaching of this element in the field might be important, potentially affecting the reliability of estimated transfer parameters of 99 Tc as measured in closed experimental systems such as hydroponics or pot experiments. The aim of this experiment was to measure the leaching of 99 Tc in undisturbed irrigated soil cores under cultivation as well as plant uptake and to study the possible competition between the two transfer pathways. Undisturbed soil cores (50x50 cm) were sampled from a Rendzic Leptosol (R), a colluvial Fluvic Cambisol (F) and a Dystric Cambisol (D) using PVC tubes (three cores sampled per soil type). Each core was equipped with a leachate collector at the bottom, allowing the monitoring of 99 Tc leaching through the cores. Cores were placed in a greenhouse and maize (Zea mays L., cv. DEA, Pioneer[reg]) was sown. After 135 d, maize was harvested and radioactivity determined in both plant and water samples. Results showed that during the growing period, leaching of 99 Tc was limited, due to the high evapotranspiration rate of maize. After harvest, leaching of 99 Tc went on because of the absence of evapotranspiration. Effective uptake (EU) of 99 Tc in leaves and grains was calculated. EU reached 70% of the input in the leaves and was not significantly different among soils. These results confirmed those obtained from pot experiments, even though leaching was allowed to occur in close-to-reality hydraulical conditions. As a consequence, it was concluded that pot experiments are an adequate surrogate for more complex 'close-to-reality' experimental systems for measuring transfer factors

  12. Phytogeographical patterns of dry forests sensu stricto in northern Minas Gerais State, Brazil.

    Science.gov (United States)

    Arruda, Daniel M; Ferreira-Júnior, Walnir G; Duque-Brasil, Reinaldo; Schaefer, Carlos E R

    2013-01-01

    The Deciduous Complex that occurs in northern Minas Gerais State, Brazil, raises questions about the floristic affinities of these formations in relation to neighboring phytogeographical domains. Little is known about the identity of the seasonal forest formations that comprise this complex, or about its relationships to abiotic components, such as soils, topography and climate. This study aimed to recognize the patterns of floristic similarity of all studied fragments of dry forest of northern Minas Gerais with soil and climate attributes, based on the available database. Cluster analysis indicated the existence of two floristic groups that had clear associations with either the Koppen's BSh (semi-arid) or Aw (seasonal tropical) climates. Likewise, the subdivisions of these groups showed clear associations with the dominant soil classes in the region. The Red-Yellow Latosol is the dominant soil classes in the BSh climatic domain, seconded by alluvial areas associated with Fluvic Neosols. The Aw domain comprised a much varied set of soils: Nitosols, Argisols, Cambisols and Litholic Neosols, most derived from the Bambuí limestone/slate formation. The ecotonal nature of northern Minas Gerais State provides a complex interaction between the flora of neighboring phytogeographical domains. This, allied to pedogeomorphological factors, allowed a better understanding of the effects of late Quaternary climate changes for the Deciduous Complex evolution. We conclude that the Latosols under present-day semi-arid climates (BSh) are relicts of former wetter climates, during which humid forest (semideciduous) expansion took place. Later, these semideciduous forests were subjected to a much drier climate, when selection for deciduousness led to the present-days Deciduous Complex scenario.

  13. Caracterização e classificação de Neossolos da Ilha de Fernando de Noronha (PE Characterization and classification of Neosols on the Fernando de Noronha Island, Pernambuco, Brazil

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    Flávio Adriano Marques

    2007-12-01

    Archipelago of Fernando de Noronha, the dry tropical climate with oceanic influence and the parent material of volcanic origin are responsible for low soil weathering. The peculiar conditions are of particular scientific interest with a view to the improvement of the Brazilian Soil Classification System (SiBCS. For this purpose, the morphological, physical, chemical and mineralogical attributes of seven representative soil profiles (two Lithic Neosols, one "Saprolithic" Neosol, three Regolithic Neosols and one Fluvic Neosol were characterized and classified. The lithic contact (R of the Lithic Neosol consisted of coarse fragments of less than 50 cm deep rocks. The Saprolithic Neosol shows lithic contact beneath 50 cm depth but is preceded by a layer of weathered soft rock with original structure. The Regolithic Neosols are related with marine sedimentary deposits of the coastal areas and formed by bioclastic carbonate material from reefs, algae and sea animals. The layers of the Fluvic Neosol, developed on colluvial- alluvial sediments, have alternating texture and mineralogy. The Lithic Neosols were adequately classified at the subgroup level according to the SiBCS, 2nd edition (Embrapa, 2006, proposed as a new subgroup "fragmentary", based on our study. The other Neosols were not adequately classified, either due to peculiar characteristics, or due to the lack of more specific terms that would describe the distinct characteristics more precisely. This study suggests the following adaptations of the SIBCS: inclusion of a new suborder of Saprolithic Neosols, of a new large group of Psamitic Regolithic Neosols and of new subgroups of bioclastic carbonate Psamitic Regolithic Neosols and bioclastic carbonate Ta Eutrophic Fluvic Neosols.

  14. Levantamento do meio físico das Estações Ecológica e Experimental de Itirapina, São Paulo, Brasil. Physical environment of Itirapina Ecological and Experimental Stations, São Paulo State, Brazil.

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    Dimas Antonio da SILVA

    2005-06-01

    , interpretation of aerial photographs andfield works. The study area bears a year average airtemperature and precipitation of 21.9ºC and1,458.9 mm, respectively Two morphologicalgroups are presented: wide hills and alluvial fans.Wide hills, covered by cerrado and plantation ofPinus spp. and Eucalyptus spp., consist ofsandstones from Botucatu Formation over whichQuartzarenics Neosoils are primarily developed.Most sharp coastal cliffs are fragile to erosionprocesses. Alluvial fans are characterized by plainland formed by recent sediments, originatingGleisoils and Organosoils. Its original vegetationis the wetland. Drainage ways are subject to flood,and rivers aggradations. Drainage ways are formedby two rivers (Itaqueri and Lobo, which target theLobo dam. It was concluded that hills and alluvialfans’ sections bearing higher degree of vegetationconservation, and particularly susceptible to linearerosion and alluvial dynamics, should integrate thezones of more restricted use. However, moremodified areas may compose recovering zones orzones of higher use intensity, considering soilconservation measures.

  15. Fatores de retardamento e coeficientes de dispersão-difusão de fosfato, potássio e amônio em solos de Minas Gerais Retardation factors and dispersion-diffusion coefficients of phosphate, potassium and ammonium in soils of Minas Gerais - Brazil

    Directory of Open Access Journals (Sweden)

    Ermelinda M. M. Oliveira

    2004-12-01

    Full Text Available Através deste estudo objetivou-se comparar os fatores de retardamento (R e os coeficientes de dispersão-difusão (D do fosfato, potássio e amônio, determinados em cinco solos de Minas Gerais (um Neossolo Quartzarênico órtico - RQo; três Latossolos Vermelhos distróficos - LVd1, LVd2 e LVd3; e um Latossolo Vermelho-Amarelo distrófico - LVAd. O experimento foi realizado utilizando-se colunas de percolação, que receberam aplicações de uma das soluções resultantes das oito possíveis combinações de duas concentrações de fosfato, potássio e amônio (15 e 60 mg L-1 de P, 75 e 300 mg L-1 de K e 15 e 60 mg L-1 de N. Valores menores de R para o potássio e o amônio, foram observados, quando comparados com os do fosfato. O R para fosfato foi menor no solo mais arenoso (RQo e maior no mais oxídico (LVd2, enquanto nos Latossolos os maiores valores do R para potássio e amônio estiveram relacionados com o incremento do teor de argila, sem tendência definida quanto á concentração do íon em estudo ou do íon acompanhante. Não se evidenciou relação nítida entre as concentrações de fosfato, potássio e amônio e os D desses íons nos solos estudados.The objective of this study was to compare the retardation factors (R, and dispersion-diffusion coefficients (D of phosphate, potassium and ammonium, determined in five Brazilian soils from Minas Gerais State (Orthic Quartzarenic Neosoil, RQo; three distrophic Red Latosols, LVd1, LVd2 and LVd3; and a distrophic Yellow-Red Latosol, LVAd. The experiment used percolation columns, applying one of the eight possible solutions resulting from the mixture of two phosphate, potassium and ammonium concentrations (15 and 60 mg L-1 P, 75 and 300 mg L-1 K, and 15 and 60 mgL-1 N. Lower values of R were observed for potassium and ammonium compared to phosphate. The value of R for phosphate was the lowest in the most sandy soil (RQo and highest in the most oxidic soil (LVd2. The highest Latosol

  16. Diferentes fontes de P no desenvolvimento do meloeiro e disponibilidade de fósforo no solo Use of biofertilizantes phosphated of the development of the melon and readiness of phosphorus

    Directory of Open Access Journals (Sweden)

    Michelangelo de Oliveira Silva

    2011-06-01

    Full Text Available Avaliou-se o desenvolvimento da cultura do melão, como também a disponibilidade de fósforo nos solos com o uso de biofertilizante fosfatado após três ciclos da cultura. Os tratamentos foram distribuídos em blocos casualizados com três repetições, arranjados num fatorial 2 x 3 x 7, correspondente a dois tipos de solos (Latossolo Amarelo e Neossolo Flúvico; três fontes de fósforo (superfosfato triplo, biofertilizante fosfatado e a rocha fosfatada; e sete níveis de fósforo (0; 0,5; 1,0; 1,5; 2,0; 2,5; 3,0 do recomendado para a cultura e para cada solo. Os fertilizantes superfosfato triplo, biofertilizante de rocha fosfatada e rocha fosfatada não apresentaram diferenças significativas na produção de matéria seca, porém o biofertilizante foi o que mais disponibilizou P nos dois solos estudados após três ciclos da mesma cultura.This work assessed the development of melon crops,and the availability of phosphorus in the soil with the use of biofertilizer phosphate after three cycles of culture. The treatments were distributed into randomized block design with three repetitions, arranged in a factorial 2 x 3 x 7, corresponding to two types of soils (Yellow Latossol and Fluvic Neosol; three sources of phosphorus (triple superphosphate, bio-fertilizer phosphate and rocks and seven levels of phosphorus (0; 0.5; 1.0; 1.5; 2.0; 2.5; 3.0 of recommended for the culture and for each soil. The triple superphosphate fertilizer, biofertilizer rock phosphate and rock phosphate showed no significant differences in dry matter production, but the biofertilizer was the most available P in both soils after three cycles of the same culture.

  17. Yield Response of Spring Maize to Inter-Row Subsoiling and Soil Water Deficit in Northern China.

    Science.gov (United States)

    Liu, Zhandong; Qin, Anzhen; Zhao, Ben; Ata-Ul-Karim, Syed Tahir; Xiao, Junfu; Sun, Jingsheng; Ning, Dongfeng; Liu, Zugui; Nan, Jiqin; Duan, Aiwang

    2016-01-01

    Long-term tillage has been shown to induce water stress episode during crop growth period due to low water retention capacity. It is unclear whether integrated water conservation tillage systems, such asspringdeepinter-row subsoiling with annual or biennial repetitions, can be developed to alleviate this issue while improve crop productivity. Experimentswere carried out in a spring maize cropping system on Calcaric-fluvicCambisolsatJiaozuoexperimentstation, northern China, in 2009 to 2014. Effects of threesubsoiling depths (i.e., 30 cm, 40 cm, and 50 cm) in combination with annual and biennial repetitionswasdetermined in two single-years (i.e., 2012 and 2014)againstthe conventional tillage. The objectives were to investigateyield response to subsoiling depths and soil water deficit(SWD), and to identify the most effective subsoiling treatment using a systematic assessment. Annualsubsoiling to 50 cm (AS-50) increased soil water storage (SWS, mm) by an average of8% in 0-20 cm soil depth, 19% in 20-80 cm depth, and 10% in 80-120 cm depth, followed by AS-40 and BS-50, whereas AS-30 and BS-30 showed much less effects in increasing SWS across the 0-120 cm soil profile, compared to the CK. AS-50 significantly reduced soil water deficit (SWD, mm) by an average of123% during sowing to jointing, 318% during jointing to filling, and 221% during filling to maturity, compared to the CK, followed by AS-40 and BS-50. An integrated effect on increasing SWS and reducing SWD helped AS-50 boost grain yield by an average of 31% and biomass yield by 30%, compared to the CK. A power function for subsoiling depth and a negative linear function for SWD were used to fit the measured yields, showing the deepest subsoiling depth (50 cm) with the lowest SWD contributed to the highest yield. Systematic assessment showed that AS-50 received the highest evaluation index (0.69 out of 1.0) among all treatments. Deepinter-row subsoilingwith annual repetition significantly boosts yield by

  18. Fitorremediação de solos contaminados com arsênio (As utilizando braquiária Phytoremediation of arsenic-contaminated soils using Brachiaria grass

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    Alessandra Silveira Antunes Araújo

    2011-02-01

    Full Text Available Conduziu-se este trabalho, com o objetivo de avaliar o potencial fitoextrator de arsênio (As da Brachiaria decumbens Stapf., cultivada em casa de vegetação, utilizando-se seis solos: Latossolo Amarelo Distrófico (LAd, Latossolo Vermelho Distrófico (LVd, Neossolo Flúvico (RU, Neossolo Quartzarênico (RQ, Gleissolo Háplico (GX e Gleissolo Melânico (GM. O As foi adicionado aos solos na forma de arsenato de sódio heptahidratado nas doses 0, 25, 50, 200 e 800 mg kg-1. As plantas foram coletadas 55 dias após a semeadura, separadas em parte aérea e raiz e, após secagem do material em estufa, o mesmo foi digerido segundo o método 3051 da USEPA, sendo o teor de As determinado por espectrofotometria de absorção atômica (EEA com forno de grafite. Observou-se redução no desenvolvimento da braquiária de forma diferenciada nas seis classes de solo. Houve baixa translocação do As, da raiz para a parte aérea, sendo essa espécie considerada tolerante ao elemento e não hiperacumuladora, podendo ser utilizada em programas de revegetação de áreas contaminadas pelo elemento.This work evaluated the phytoextraction potential of arsenic (As by Brachiaria decumbens growing under greenhouse conditions in six soils: a Dystrophic Yellow Latosol (LAd, a Dystrophic Red Latosol (LVd, a Fluvic Neosol (RU, a Quartzenic Neosol (RQ, a Haplic Gleysol (GX, and a Melanic Gleysol (GM. Arsenic was added to the soils as sodium arsenate heptahydrate (Na2HAsO4.7H2O at the following doses: 0, 25, 50, 200, and 800 mg kg-1. The plants were collected 55 days after planting for determination of shoot and root dry matter production. Arsenic shoot and root contents were evaluated after digestion according to the USEPA 3051A method, following analysis by graphite furnace atomic absorption spectroscopy. Plant development was differently affected by As in the six different soil classes. There was low translocation of As and consequently most of the As was detected in the

  19. MERCURY CONCENTRATION IN MARGIN SOIL OF THE MADEIRA RIVER

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    Déborah Pereira Linhares

    2005-05-01

    Full Text Available The extraction of gold in the Amazon, since 1970, has grown fast from a politic that was resulted in the creation of gold extraction reserves in this region. In the Madeira River the gold exploration is noticeable because of the deposition of mercury in the environment. This metal is toxic and it resists to degradation process, transforming itself chemically, till it gets to its organic form, known as very toxic. Its extensive usage in the gold recover has caused impacts to the environment and consequently to the population, according to studies already done. This study has as its goal to value the pollution by Hg in soils and the variation according to soil fractions. The soils were collected by profiles in 10 areas in the Madeira River. The determination of organic matter was done, according (BRASIL, 1999.To Hg determination it was selected the fraction <200 mesh (<74ım, analyzed by atomic absorption spectrophotometer coupled vapor cold generation (Bastos et. al, 1998. Soils of the kind Latosols and hydromorphic were identified. The Latosols presented from 288 to 641g.Kg-1 of clay and from 266 to 111 g.Kg-1 of thin send, from the horizon A1 (superficial to B2 (sub-superficial. The increase of values of clay makes the function of organic matter in the superficial horizon better (from 20,2 to 19.0 %. The Hg concentration in these horizons varies from 25,5 to 641,4 ıg.Kg-1in the superficial horizon. The hydromorphic, especially, the Fluvic Neosols, present thin area, 396 to 57 g.Kg-1 and clay from 254 to 654 g.Kg-1 from A1 to A2. The horizon A2 presents 467 g.Kg-1 of silt, 13,6 % of OM and 147,31 ıgHg.Kg-1.Among the soils groups of the studied area, it is noticed more Hg concentration with the increase of values of silt and clay, that consequently presents more tenor of OM, and that subsidizes the organic mercury forming.

  20. Spectral characterization of the fluorescent components present in humic substances, fulvic acid and humic acid mixed with pure benzo(a)pyrene solution

    Science.gov (United States)

    El Fallah, Rawa; Rouillon, Régis; Vouvé, Florence

    2018-06-01

    The fate of benzo(a)pyrene (BaP), a ubiquitous contaminant reported to be persistent in the environment, is largely controlled by its interactions with the soil organic matter. In the present study, the spectral characteristics of fluorophores present in the physical fractions of the soil organic matter were investigated in the presence of pure BaP solution. After extraction of humic substances (HSs), and their fractionation into fluvic acid (FA) and humic acid (HA), two fluorescent compounds (C1 and C2) were identified and characterized in each physical soil fraction, by means of fluorescence excitation-emission matrices (FEEMs) and Parallel Factor Analysis (PARAFAC). Then, to each type of fraction having similar DOC content, was added an increasing volume of pure BaP solution in attempt to assess the behavior of BaP with the fluorophores present in each one. The application of FEEMs-PARAFAC method validated a three-component model that consisted of the two resulted fluorophores from HSs, FA and HA (C1 and C2) and a BaP-like fluorophore (C3). Spectral modifications were noted for components C2HSs (C2 in humic substances fraction) (λex/λem: 420/490-520 nm), C2FA (C2 in fulvic acid fraction) (λex/λem: 400/487(517) nm) and C1HA (C1 in humic acid fraction) (λex/λem: 350/452(520) nm). We explored the impact of increasing the volume of the added pure BaP solution on the scores of the fluorophores present in the soil fractions. It was found that the scores of C2HSs, C2FA, and C1HA increased when the volume of the added pure BaP solution increased. Superposition of the excitation spectra of these fluorophores with the emission spectrum of BaP showed significant overlaps that might explain the observed interactions between BaP and the fluorescent compounds present in SOM physical fractions.

  1. Genesis and classification of the soils developed from the sediments of the former Oleszek mill pond basin (the Chełmińskie Lakeland, N Poland / Geneza i pozycja systematyczna gleb wykształconych z osadów niecki dawnego stawu młyńskiego Oleszek (Pojezierze Chełmińskie

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    Mendyk Łukasz

    2015-03-01

    Full Text Available Budowa i funkcjonowanie młynów wodnych znacznie wpłynęły na przekształcenie środowiska przyrodniczego w ich otoczeniu, przede wszystkim na zmiany rzeźby terenu i warunków wodnych. Obszar badañ obejmuje nieckę dawnego stawu młyńskiego Oleszek w okolicach wsi Borówno, w zachodniej części Pojezierza Chełmińskiego, około 20 km na północny wschód od Torunia. Celem badañ było określenie genezy gleb wykształconych z osadów zakumulowanych w niecce dawnego stawu młyńskiego Oleszek. Pięć profili glebowych w transekcie o długości około 550 m zlokalizowanym wzdłuż Strugi Rychnowskiej stanowiącej oś podłużną niecki. Wszystkie przeanalizowane gleby zbudowane są z osadów wypełniających nieckę dawnego stawu młyńskiego. Gleby w opisywanej niecce powstały w wyniku wielu nakładających się procesów, takich jak: proces mułotwórczy, aluwialny, koluwialny oraz glejowy. Dwa z analizowanych profili glebowych (profile 3 i 4 spełniaj¹ kryteria wydzielania gleb organicznych limnowych typowych (Systematyka gleb Polski 2011. Jako pozycję systematyczną kolejnych dwóch gleb (profile 2 i 5 zaproponowano gleby mułowate. W związku z problemami klasyfikacyjnymi dotyczącymi tego typu gleb, przy opracowaniu aktualizacji Systematyki gleb Polski należałoby wprowadzić w typie gleb glejowych podtyp gleb mułowatych lub mułowato-glejowych, obejmuj¹cy gleby wytworzone z mineralno-organicznych utworów aluwialno-mułowych. Cztery wymienione powyżej profile zostały zaklasyfikowane jako Histosols (3 i 4 i Gleysols (2 i 5 według klasyfikacji WRB (2014. Jednostki glebowe wykształcone z osadów aluwialnych (mady wg SgP 2011 lub Fluvic Phaeozems wg WRB 2014 występują w proksymalnej części stawu (cofce.

  2. Mobilidade do ametryn em solos da região semiárida do Rio Grande do Norte Ametryn mobility in soils of Rio Grande do Norte semiarid region

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    F.C.L. Freitas

    2012-09-01

    profundidade. O método do bioensaio com pepino como planta indicadora pode ser utilizado em estudos de lixiviação desse herbicida, em substituição ao método cromatográfico.This work aimed to evaluate ametryn mobility in four types of soils, three from the semiarid region of the state of Rio Grande do Norte (Cambisol ; Fluvic Neosol; Latosolic Dystrophic Red-Yellow Argisol and one from the state of Minas Gerais (Red-Yellow Latosol. Ametryn mobility was evaluated using PVC columns of 10 cm in diameter and 50 cm long. The experiment was conducted in a split-plot in a completely randomized design with four replications. The plots were composed by the columns, filled with the four types of soils and the subplots by 10 depths at intervals of 5 cm (0-5, 5-10, 10-15, 15-20, 20-25, 25-30 , 30-35, 35-40, 40-45 and 45-50 cm. Ametryn was applied on top of the columns (4 kg ha-1 and, 12 hours later, rainfall was simulated at the intensity of 60 mm. After 72 hours of simulated rain, the columns were placed in a horizontal position and opened longitudinally, divided into sections of 5.0 cm. At the center of each section, soil samples were collected for subsequent herbicide extraction and quantification through analysis by liquid chromatography (HPLC. Five seeds of cucumber (Cucumis sativus were sown as bio-indicators of the presence of the herbicide. Ametryn mobility at the columns was influenced by the physical and chemical characteristics of the soil,(soil texture, organic matter, and pH. The Rio Grande do Norte semiarid region soils had higher ametryn mobility potential, being detected at up to 25, 20, and 15 cm depth in Latosolic Dystrophic Red- Yellow Argisol, Cambisol, and Fluvic Neosol, respectively. Ametryn mobility was restricted to 5 cm depth in the Red Yellow Latosol, with higher organic matter content and pH 4.7. The bioassay method was more efficient to confirm ametryn leaching than liquid chromatography.

  3. Resistência hidráulica da crosta formada em solos submetidos a chuvas simuladas Crust hydraulic resistance in soils under simulated rain

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    Viviane dos Santos Brandão

    2006-02-01

    Full Text Available Para avaliar a redução da taxa de infiltração em solos sujeitos ao encrostamento decorrente da aplicação de chuvas simuladas, foi realizado um experimento em esquema fatorial 5 x 6, sendo cinco solos (Argissolo Vermelho, Argissolo Vermelho-Amarelo, Latossolo Vermelho-Amarelo, Neossolo Flúvico e Neossolo Quartzarênico e seis energias cinéticas de chuva (0, 525, 1051, 2102, 3153 e 4204 J m-2, com três repetições. A partir dos dados de taxa de infiltração da água no solo e da espessura da crosta, determinadas por micromorfometria, calcularam-se a condutividade e a resistência hidráulica da crosta. Todos os solos apresentaram redução da taxa de infiltração, quando a energia cinética de chuva simulada aplicada aumentou. A resistência hidráulica da crosta aumentou com a energia cinética (especialmente para os solos Argissolos Vermelho-Amarelos e Vermelho até atingir um valor máximo, a partir do qual ocorreu diminuição, atribuída ao desgaste erosivo da crosta provocado pelo aumento do escoamento superficial, associado aos maiores valores de energia cinética da chuva simulada. Por meio de análise de regressão múltipla, foram determinadas a relação da resistência hidráulica da crosta com a energia cinética da chuva e as características químicas e físicas de cada solo. A variável resistência hidráulica da crosta mostrou-se adequada a ser utilizada nos modelos infiltração da água no solo para descrever a influência do encrostamento neste processo.To evaluate the decrease in infiltration rate in crusting soils an experiment was carried out using a rainfall simulator. Treatments were distributed in a factorial schedule 5 x 6, using five soils (Red Ultisol, Red-Yellow Ultisol, Red-Yellow Oxisol, Fluvic Entisol and Arenic Entisol and six rainfall kinetic energies (0, 525, 1051, 2102, 3153, and 4204 J m-2 with three replications. According to the water infiltration rate and crust thickness, as determined by

  4. Uncertainties and Solutions Related to Use of WRB (2007) in the Boreo-nemoral zone, Case of Latvia

    Science.gov (United States)

    Kasparinskis, Raimonds; Nikodemus, Olgerts; Rolavs, Nauris

    2014-05-01

    Relatively high diversity of soils groups according to the WRB (2007) classification is observed in forest ecosystems in the boreo-nemoral zone in Latvia. This is due to the geological genesis of area and environmental conditions (Kasparinskis, Nikodemus, 2012), as well as historical land use and management (Nikodemus et al., 2013). Due to the relatively young soils, Albic, Spodic and Cambic horizons are relatively weakly expressed in many cases. Relatively well developed Albic horizons occur in sandy forest soils, but unusually well expressed Spodic features are observed. In some cases there is a Cambic horizon, however location of Cambisols in the WRB (2007) soil classification sequence does not provide an opportunity to classify these soils as Cambisols, but they are classified as Arenosols. This sequence does not reflect the logical sheme of soil development, and therefore raises the question about location of Podzols, Arenosols and Cambisols in the sequence of WRB (2007) soil classification. Soils with two parent materials (abrupt textural change) are relatively common in Latvia, where conceptually on the small scale mapping results in classification as the soil group Planosols, but in many cases there is occurrence of Fluvic materials, as parent material in the upper part of the soil profile is formed by Baltic Ice lake sandy sediments - this leads to question about the location of Fluvisols and Planosols in the sequence of the WRB (2007) soil classification. Soil research has found cases, where a relatively well developed Spodic horizon was established as the result of ground water table depth in areas of abrupt textural change. In this case the profile corresponds to the soil group of Podzols, however in some cases - Gleysols not Planosols due to a high ground water table. Therefore there is a need for discussion also about the location of Podzols and Planosols in the sequence of the WRB (2007) soil classification. The above mentioned questions raise

  5. Condicionadores químicos e orgânicos na recuperação de solo salino-sódico em casa de vegetação Chemical and organic amendments in reclamation of saline-sodic soil in greenhouse

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    Marcelo A. Miranda

    2011-05-01

    Full Text Available A salinização vem promovendo a degradação de solos no Semiárido do Brasil, os quais precisam ser recuperados para que possam ter utilização agrícola. Este trabalho teve como objetivo avaliar o efeito de condicionadores orgânicos e químicos em atributos físico-hídricos de um Neossolo Flúvico salino-sódico, no Sertão de Pernambuco. O experimento foi instalado em colunas de solo, sendo aplicados 10 tratamentos: esterco ovino, esterco bovino, gesso, seis doses de polímero sintético e a testemunha, em delineamento em blocos casualizados. As colunas foram submetidas a lixiviação durante 70 dias e analisadas as soluções percoladas aos sete e 70 dias e os solos após a lixiviação. Nos lixiviados foram medidos o pH e a CE e determinados os teores de Na+, K+ e Cl-; no solo foram medidos o pH e a CE e determinado o teor de Na+ do extrato de saturação, o teor de Na+ trocável e a CTC, para cálculo da PST, além das variáveis físico-hídricas do solo. Os resultados foram submetidos a análise de variância e teste de Scott Knott a 0,05 de probabilidade. Os tratamentos, especialmente os estercos, o gesso e o polímero na menor concentração, diminuíram a CE, a PST e o Na+ solúvel, aumentando a condutividade hidráulica do solo.The salinization is degrading Brazilian semi-arid soils, which need to be reclaimed for agricultural utilization. This work aimed to evaluate use of organic and chemical amendments in a Fluvic Entisol having saline-sodic properties in Pernambuco's semi-arid region. Soil experiment was conducted in soil columns, with 10 treatments: sheep manure, cow manure, gypsum, synthetic polymer in six concentrations and the control, in randomized block design. The columns were submitted to leaching during 70 days, being analyzed the leachates collected at 7 and 70 days and the soil after leaching. In leachates, the pH, EC and concentration of Na+, K+ and Cl- were determined; in the saturation extract, pH and EC were

  6. Efeitos da compactação do solo e do manejo da água sobre os componentes de produção e a produtividade de grãos de arroz Effects of soil compaction and water management upon yield components and rice grain yields

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    Roberto Dantas de Medeiros

    2005-10-01

    . The results stressed that soil compaction tends to reduce the number os panicles per pot, sterility of spikelets and grain yield. At moderate compaction levels, there was an increase of the number of filled grain per panicle, taking into account the three water management. Moisture favored production components: the number of panicles per pot, the number of filled grain per panicle and spikelet sterility, contributing toward increased yield. Thus, it follows that soil moisture was more determinant than compaction as a limiting factor to grain yield and, that, for Fluvic Neosol, compaction per si is not a factor limiting to a possible adoption of the no-tillage system with lowland rice.

  7. Organic residue, limestone, gypsum, and phosphorus adsorption by lowland soils Resíduo orgânico, calcário e gesso e a adsorção de fósforo por solos de várzea

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    Alex Teixeira Andrade

    2002-06-01

    Full Text Available Organic residue application is a low cost alternative to reduce the use of inorganic fertilizers and correctives. In order to study the effect of organic residues, limestone and gypsum application on phosphorus adsorption by lowland soils, four experiments were carried out. A Mesic Organosol (OY, a Melanic Gleysol (MG, a Haplic Gleysol (GX, and a Fluvic Neosol (RU were used in a completely randomized design and factorial scheme (3 x 2, with five replicates: three soil amendment practices (limestone, gypsum and no corrective and two levels of organic residue (with and without corral manure. Soil samples were incubated for 60 days, with and without organic residue incorporation. After this period, we applied the corrective and incubated the soil for 30 days, then P and basic fertilization (macro and micronutrients were applied and the soil was incubated for additional 60 days. Equilibrium phosphorus, maximum phosphate adsorption capacity, pH, exchangeable Al and phosphorus-buffering index were measured. Organic residue and limestone application increased soil pH and reduced exchangeable Al, decreasing P adsorption. Gypsum application did not increase the pH but reduced exchangeable Al and P adsorption.A aplicação de resíduo orgânico é uma alternativa de baixo custo para reduzir a aplicação de fertilizantes inorgânicos e corretivos. Com objetivo de estudar a relação da aplicação de resíduo orgânico, calcário e gesso com adsorção de fósforo em solos de várzea conduziram-se simultaneamente quatro experimentos com os solos Organossolo Mésico (OY, Gleissolo Melânico (GM, Gleissolo Háplico (GX e Neossolo Flúvico (RU. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 3x2, com cinco repetições, sendo três práticas de correção do solo (calcário, gesso e sem corretivo e dois níveis de resíduo orgânico com e sem esterco de curral curtido. Amostras dos solos foram incubadas por 60 dias

  8. Características hidráulicas e perdas de solo e água sob cultivo do feijoeiro no semi-árido Hydraulic characteristics and soil and water losses under bean cultivation in the semiarid

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    Thais E. M. dos Santos

    2009-06-01

    Full Text Available A região semi-árida apresenta chuvas escassas, irregulares e de secas freqüentes, sendo usual a ocorrência de eventos de alta intensidade. Os solos são pedregosos e rasos, dificultam a prática regular da agropecuária, comprometem freqüentemente a produtividade e tornam esses ambientes vulneráveis à erosão. Objetivou-se avaliar o desempenho de práticas conservacionistas sob a cultura do feijoeiro, no controle de perdas de solo e água por erosão hídrica, em Neossolo Flúvico do semi-árido, com cultivo de sequeiro. Chuvas simuladas com intensidades de 60 mm h-1 foram aplicadas sobre os seguintes tratamentos: cultivo em nível (N1 com barramentos de pedra entre cada fileira de plantio, no espaçamento de 0,5 m; cultivo em nível (N2 com barramentos de pedra no espaçamento de 1,0 m; cultivo morro abaixo (MA; cultivo em nível com cobertura morta (CM, de palha de feijão; parcelas desmatadas (D e com cobertura natural (CN. Dentre os tratamentos avaliados, verificou-se que a adoção de cobertura morta permitiu, em média, redução nas perdas de solo de 86,91% em relação à parcela sem cobertura, com valores próximos ao da condição ideal de cobertura, que é a condição natural, durante todo o ciclo da cultura.The semiarid zone presents scarce and irregular rainfall with frequent droughts, with the occurrence of high intensity events being usual. The soils are shallow and stony, which limits regular agriculture practice, usually reducing productivity and turning this environment susceptible to erosion. The objective of this study was to evaluate the influence of conservation practices, under bean crop, upon soil and water losses by the hydric erosion, in a Fluvic Neossol in the semiarid zone, with rainfed crop. Simulated rainfall has been applied with 60 mm h-1 intensity under the following treatments: cultivation in contour lines (N1 with rock barriers between each row of plantation, spacing 0.5 m; cultivation in contour lines

  9. Teor de arsênio e adsorção competitiva arsênio/fosfato e arsênio/sulfato em solos de Minas Gerais, Brasil Arsenate content, and arsenate/phosphate and arsenate/sulphate competitive adsorption in soils from Minas Gerais, Brazil

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    Mari Lucia Campos

    2013-06-01

    Full Text Available A alta toxicidade de As para homens e animais gera a necessidade de estudos do comportamento químico do arsenato nos solos que possam auxiliar na mitigação de áreas contaminadas com arsênio. Este trabalho teve por objetivo avaliar o teor total e a adsorção de As na ausência e presença dos ânions fosfato e sulfato em seis diferentes classes de solos do estado de Minas Gerais, Brasil. Os solos alvo deste estudo são: o Neossolo Flúvico (RU, Gleissolo Háplico (GX, Gleissolo Melânico (GM, Latossolo Vermelho Distrófico (LVd, coletados em Lavras; Neossolo Quartzarênico (RQ, coletado em Itutinga e o Latossolo Amarelo Distrófico (LAd, coletado em Rosário, no estado de Minas Gerais. As amostras de solo foram secas, moídas e peneiradas em peneira de 2,0mm para execução do teste de adsorção e peneiradas em peneira plástica com malha de 1,5mm para determinação do teor de As, o qual foi determinado pelo método 3051A. A adsorção de As foi avaliada na dose de1500µmol L-1 de As, 1500µmol L-1 de As + 1500µmol L-1 de P e 1500µmol L-1 de As + 750µmolL-1 de S, em relação solo:solução final de 1:100, a pH 5,5 e força iônica de 15mmol L-1. Os seis solos apresentaram teor médio de As entre 0,14 e 9,3mgkg-1. A porcentagem adsorvida de arsênio na ausência dos outros ânions seguiu a sequência GM>LVd=RU=LAd=GX=RQ. A adição de fosfato e sulfato reduziu a porcentagem de arsênio adsorvido e, por consequência, houve um aumentou na concentração de arsênio disponível na solução do solo.The high toxicity of arsenic to humans and animals creates the need to study the chemical behavior of arsenate in soils that can help in the mitigation of areas contaminated with arsenic. This work aimed to evaluate the total content and adsorption in the absence and presence of phosphate and sulfate anions in six different soil classes in the state of Minas Gerais, Brazil. Soils aim of this study are: Fluvic Neosol (RU, Haplic Gleysol (GX

  10. Solos do topo da Serra São José (Minas Gerais e suas relações com o paleoclima no Sudeste do Brasil Soils of the São José Hills (Minas Gerais State, Brazil and their relationship with palaeoclimate in Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    A. C. Silva

    2004-06-01

    sand layers, were identified in P1. Three layers in P1 (20-30, 70-80, and 100-110 cm depth with an organic C content of 0,5, 7, and 1 dag kg-1, respectively, present radiocarbon (14C ages < 40, 180 ± 60, and 350 ± 80 years BP, respectively, and deposition rates of 0.177 cm year-1 at depths between 110 and 170 cm and of 0.357 cm year-1 between 70 and 20 cm layer. In P2, the layers enriched with organic matter are thicker (between 10 and 130 mm, with abrupt discontinuity. They lie between 20-30, 80-90 110-120, and 170-180 cm deep, have a C content of 3, 2.5, 21, and 1.5 dag kg-1, and a 14 C age of 3580 ± 80, 3750 ± 80, 21210 ± 180, and 24060 ± 130 year-1 BP, respectively. Their deposition rates are 0.352 cm year-1 between 20 and 80 cm, 0.002 cm year-1 between 80 and 110 cm and 0.021 cm year-1 at depths between 110 and 170 cm. In both soil profiles, the C/N ratio increases with depth and age. The amount of Ti and Zr, elements of low mobility, are higher in the oldest profile layers, while Cu and Pb are more concentrated in the layers higher in organic matter. A plant fragment (diameter 5 cm, 62 cm long found at the bottom of P2 dated back to 32220 ± 290 years BP, and is associated with the beginning of this profile formation. The soils at the summit of São José Hills had its origin in the Tiradentes Formation without contribution of other geologic material. Rain water is the main factor that adds energy to this environmental energy. Therefore, soil formation is related to climate attributes. P1 is a holocenic (Fluvic Entisol soil, formed by episodic depositions of sand, alternated with sand enriched with organic matter. The formation of P2 (Paleosol began in the Pleistocene and lasted until the Holocene. The morphology of its buried peat layers is related to oscillations of the water surface of a lake, reflecting drier and more humid climate phases. The assessed radiocarbonic ages are related to Pleistocene and Holocene climate alternations in P2 and holocenic in