Extração seqüencial de Mn e Zn em solos em função do pH e adição de cama-de-frango

A disponibilidade de micronutrientes catiônicos e sua distribuição nas frações do solo, são afetadas por diversos atributos, como pH e teor de matéria orgânica do solo. Avaliaram-se a disponibilidade de Mn e Zn por três extratores químicos e o fracionamento desses elementos, por meio de extração seqüencial, em função da variação do pH e da adição de cama-de-frango, em amostras da camada superficial (0 a 10 cm) de um Neossolo Litólico distrófico típico e de um Cambissolo Húmico alumínico da região da Serra do Rio Grande do Sul, cultivados com videira. Após redução dos valores de pH do solo, de 6,5 para 3,8, ocorreu aumento nos teores disponíveis de Mn e Zn e nos de Mn e Zn ligados à fração trocável, com diminuição nos teores desses elementos ligados à fração orgânica. A aplicação de doses de cama-de-frango contribuiu para aumentar os teores disponíveis e os ligados à fração trocável. A maior proporção do Mn dos solos estudados esteve ligada à fração orgânica (35%) e à fração residual (30%); para o Zn, a maior proporção foi observada na fração residual (55%). Os teores de Mn e Zn extraídos com DTPA, com CaCl2 0,01 mol L-1 e com Mehlich III, apresentaram relação linear com os teores dos elementos nas frações trocável e ligada à matéria orgânica

Copper concentration of vineyard soils as a function of pH variation and addition of Poulttry litter.

Made available in DSpace on 2019-04-17T01:10:26Z (GMT). No. of bitstreams: 1 COPPER.pdf: 86877 bytes, checksum: 5ca4bc890d0578fbe7347c875d4b1bc2 (MD5) Previous issue date: 2007bitstream/item/195909/1/COPPER.pd

Sequential extraction and availability of copper in Cu fungicide-amended vineyard soils from Southern Brazil.

Three laboratory column experiments were performed to test the suitability of two different MgO-rich reagents for removal of Mn and Al from the out-?owing waters of Shilbottle passive treatment system (Northumberland, UK). The input water was doped with 100mg/L Zn in order to extrapolate results to waters in sulphide mining districts. One column was ?lled with a Dispersed Alkaline Substrate (DAS) containing 12.5% (v/v) causticmagnesia precipitator dust (CMPD) fromSpainmixedwithwood shavings, two columns were ?lled with DAS containing wood shavings and 12.5% or 25% (v/v), respectively, of dolomitic lime precipitator dust (DLPD) from Thrislington, UK. The two columns containing 12.5% of CMPD or DLPD completely removed the contaminants from the in?ow water during the ?rst 6 weeks of the experiment (mean removal of 88mg/L Al, 96mg/L Zn and 37mg/LMn), operating at an acidity load of 140 g acidity/m2 day. At thismoment, a substantial increase of theAl andMnwater concentration in the out-?owingwaters of Shilbottle occurred (430 g acidity/m2 day), leading to passivation of the reactive material and to the development of preferential ?ow paths within less than another 6 weeks, probably mainly due to Al precipitates. Al should be removed prior to MgO treatment.Made available in DSpace on 2019-04-04T00:31:26Z (GMT). No. of bitstreams: 1 SEQUENTIALEXTRACTION.pdf: 333657 bytes, checksum: 3edcd019a604e0e1d4d55de6e03894f7 (MD5) Previous issue date: 2010bitstream/item/195349/1/SEQUENTIAL-EXTRACTION.pd

Sequential extraction and availability of copper in Cu fungicide-amended vineyard soils from Southern Brazil.

Three laboratory column experiments were performed to test the suitability of two different MgO-rich reagents for removal of Mn and Al from the out-?owing waters of Shilbottle passive treatment system (Northumberland, UK). The input water was doped with 100mg/L Zn in order to extrapolate results to waters in sulphide mining districts. One column was ?lled with a Dispersed Alkaline Substrate (DAS) containing 12.5% (v/v) causticmagnesia precipitator dust (CMPD) fromSpainmixedwithwood shavings, two columns were ?lled with DAS containing wood shavings and 12.5% or 25% (v/v), respectively, of dolomitic lime precipitator dust (DLPD) from Thrislington, UK. The two columns containing 12.5% of CMPD or DLPD completely removed the contaminants from the in?ow water during the ?rst 6 weeks of the experiment (mean removal of 88mg/L Al, 96mg/L Zn and 37mg/LMn), operating at an acidity load of 140 g acidity/m2 day. At thismoment, a substantial increase of theAl andMnwater concentration in the out-?owingwaters of Shilbottle occurred (430 g acidity/m2 day), leading to passivation of the reactive material and to the development of preferential ?ow paths within less than another 6 weeks, probably mainly due to Al precipitates. Al should be removed prior to MgO treatment