Consulta: subjectFacets:"Amazonian soils"
Registros recuperados: 4
Data/hora: 09/06/2024 07:45:22

Diuron Sorption, Desorption and Degradation in Anthropogenic Soils Compared to Sandy Soil
Provedor de dados: 87
Autores: ALMEIDA,C.S.; MENDES,K.F.; JUNQUEIRA,L.V.; ALONSO,F.G.; CHITOLINA,G.M.; TORNISIELO,V.L.
ABSTRACT: The aim of this study was to evaluate diuron sorption, desorption and degradation in two anthropogenic soils (Terra Preta de Índio - TPI) in contrast to a sandy soil (Quartzarenic Neosol - NQo). Sorption-desorption studies were performed by the batch equilibrium method and biodegradation in biometric bottles using radiolabeled diuron in 14C. Freundlich coefficient (Kf) values ranged from 13.50 to 50.41 µmol(1-1/n) L1/n kg-1 in TPI-2 and TPI-1, respectively, indicating very high diuron sorption in anthropogenic soils, following the order: TPI-1 ≥ TPI-2 &gt; NQo (99.10, 98.95 and 60.8%, respectively). Diuron desorption was very low in anthropogenic soils, ranging from 1.36 (TPI-1) to 1.70% (TPI-2), and 24% to NQo. Accumulated diuron mineralization...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bound residue; Mineralization; Sorption isotherms; Amazonian soils.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582020000100233

Pedogenesis in an Archaeological Dark Earth – Mulatto Earth Catena over Volcanic Rocks in Western Amazonia, Brazil
Provedor de dados: 90
Autores: Santos,Luís Antônio Coutrim dos; Araujo,Jane Kelly Silva; Souza Júnior,Valdomiro Severino de; Campos,Milton César Costa; Corrêa,Marcelo Metri; Souza,Regilene Angélica da Silva.
ABSTRACT Archaeological Dark Earth (ADE) pedogenesis and pre-Columbian history are fundamental for understanding the biodiversity and pedodiversity of the Neotropical rainforest in the Amazon region. This study aimed to evaluate the morphological, physical, chemical, and mineralogical properties as well as NaOH-extractable organic matter [OM(NaOH)] in ADE and Mulatto Earth (ME) overlying volcanic rocks along a toposequence (four soil profiles) in western Amazonia, Brazil. The soil profiles show anthropic A horizons over an argic horizon (Bt) in the ADE (Humic, Pretic Luvisols) and Bi in the ME (Clayic, Dystric Cambisols). The soil-forming processes in all of the profiles are associated with organic matter accumulation, such as humification and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazonian soils; Anthropogenesis; Pretic horizon; Humin; Luvisols.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100309

USE OF SCALED SEMIVARIOGRAMS IN THE PLANNING SAMPLE OF SOIL CHEMICAL PROPERTIES IN SOUTHERN AMAZONAS, BRAZIL
Provedor de dados: 90
Autores: Oliveira,Ivanildo Amorim de; Campos,Milton César Costa; Marques Junior,José; Aquino,Renato Eleotério de; Teixeira,Daniel de Bortoli; Silva,Douglas Marcelo Pinheiro da.
The lack of information concerning the variability of soil properties has been a major concern of researchers in the Amazon region. Thus, the aim of this study was to evaluate the spatial variability of soil chemical properties and determine minimal sampling density to characterize the variability of these properties in five environments located in the south of the State of Amazonas, Brazil. The five environments were archaeological dark earth (ADE), forest, pasture land, agroforestry operation, and sugarcane crop. Regular 70 × 70 m mesh grids were set up in these areas, with 64 sample points spaced at 10 m distance. Soil samples were collected at the 0.0-0.1 m depth. The chemical properties of pH in water, OM, P, K, Ca, Mg, H+Al, SB, CEC, and V were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Geostatistics; Amazonian soils; Archaeological dark earth; Sampling density.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832015000100031

Synthesis of enriched biochar as a vehicle for phosphorus in tropical soils
Provedor de dados: 36
Autores: MATOSO,Stella Cristiani Gonçalves; WADT,Paulo Guilherme Salvador; SOUZA JÚNIOR,Valdomiro Severino de; PÉREZ,Xosé Lois Otero.
ABSTRACT Phosphorus (P) is one of the nutrients that most limits agricultural productivity, especially in tropical soils. Enriched biochar has been proposed to increase the bioavailability of P and other nutrients in the soil. Thus, the objective of this study was to evaluate the availability of P in phosphate biochar (composed of biomass and soil) as a function of the triple superphosphate mixture before and after the pyrolysis process. We produced eight types of enriched biochar via pyrolysis by combining sandy or clayey soil with rice or coffee husk, and by adding triple superphosphate before or after pyrolysis. The heating of the phosphate fertilizer during the pyrolysis process resulted in a higher crystallinity of the phosphates, lower content of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazonian soils; Coffee husk; Rice husk; Pyrolysis; Triple superphosphate; Biochar quality.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672019000400268