Advances on graphene-based gas sensors for acetone detection based on its physical and chemical attributes

Abstract The objective of this work was to evaluate the use of magnetic susceptibility for characterizing the spatial variability of soil attributes and identifying areas with different potentials for sugarcane (Saccharum spp.) production. Samples were collected at 110 points (1 per 7 ha) in the layers of 0.00-0.20 and 0.20-0.40 m, to determine the magnetic susceptibility and physical and chemical attributes of the soil. Fiber content, sucrose polarization (POL), and sugarcane yield were determined in 33 points. The spatial variability model for magnetic susceptibility was 63 and 22% more accurate in delimiting soil potential for sugarcane production than soil physical and chemical attributes at the 0.0-0.2 and 0.2-0.4-m layers, respectively. The spatial variability map for magnetic susceptibility was strongly correlated with clay (0.83 and 0.89, respectively, for the layers) and sand contents (-0.84 and -0.88); moderately correlated with organic matter (-0.25 and -0.35), sum of bases (-0.46 and 0.37), cation exchange capacity (0.22 and 0.47), pH (-0.52 and 0.13), and POL (0.43 and 0.53); and weakly correlated with sugarcane yield (0.26 and 0.23). Magnetic susceptibility can be used to characterize the spatial variability of soil attributes and to identify areas with different potentials for sugarcane production.

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Physical and chemical attributes of archaeological soils developed from shell middens in the Região dos Lagos, Rio de Janeiro, Brazil

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832011000400004 ◽

2011 ◽

Vol 35 (4) ◽

pp. 1100-1111 ◽

Cited By ~ 6

Author(s):

Guilherme Resende Corrêa ◽

Carlos Ernesto G.R Schaefer ◽

Vander de Freitas Melo ◽

Kleberson Worslley de Souza ◽

João Carlos Ker ◽

...

Keyword(s):

Sandy Loam ◽

Chemical Properties ◽

Brazilian Coast ◽

High Fertility ◽

Physical Analysis ◽

Shell Middens ◽

Organic C ◽

Chemical Attributes ◽

Região Dos Lagos ◽

Physical And Chemical

In prehistoric times, innumerous shell middens, called "sambaquis", consisting mainly of remains of marine organisms, were built along the Brazilian coast. Although the scientific community took interest in these anthropic formations, especially since the nineteenth century, their pedological context is still poorly understood. The purpose of this study was to characterize and identify the physical and chemical changes induced by soil-forming processes, as well as to compare the morphology of shell midden soils with other, already described, anthropogenic soils of Brazil. Four soil profiles developed from shell middens in the Região dos Lagos - RJ were morphologically described and the physical and chemical properties determined. The chemical analysis showed that Ca, Mn, Mg, and particularly P and Zn are indicators of anthropic horizons of midden soils, as in the Amazon Dark Earths (Terras Pretas de Índio). After the deposition of P-rich material, P reaction and leaching can mask or disturb the evidence of in situ man-made strata, but mineralogical and chemical studies of phosphate forms can elucidate the apparent complexity. Lower phosphate-rich strata without direct anthropic inputs indicate P leaching and precipitation in secondary forms. The total and bioavailable contents of Ca, Mg, Zn, Mn, Cu, P, and organic C of midden soils were much higher than of regional soils without influence of ancient human settlements, demonstrating that the high fertility persisted for long periods, at some sites for more than 4000 years. The physical analysis showed that wind-blown sand contributed significantly to increase the sand fraction in the analyzed soils (texture classes sand, sandy loam and sandy clay loam) and that the aeolian sand accumulation occurred simultaneously with the midden formation.

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Ethnopedological Studies to Characterize Neosols at the Brazilian Semiarid Region

Journal of Agricultural Science ◽

10.5539/jas.v11n4p536 ◽

2019 ◽

Vol 11 (4) ◽

pp. 536

Author(s):

Jucirema Ferreira da Silva ◽

Jeane Cruz Portela ◽

Nildo da Silva Dias ◽

Cezar Augusto Medeiros Rebouças ◽

Francisco Ernesto Sobrinho ◽

...

Keyword(s):

Chemical Analysis ◽

Agricultural Soils ◽

Close Relation ◽

Soil Types ◽

Semiarid Region ◽

Brazilian Semiarid ◽

Soil Landscape ◽

Chemical Attributes ◽

Pasture Area ◽

Physical And Chemical

The ethnopedological approach to soil characterization presents great challenges, since the understanding of the systems occurs through the knowledge acquired by the man in his coexistence with agroecosystems. The aim of the present research was to characterize the agricultural soils through morphological, physical and chemical analysis, using ethnopedological studies in the ‘Santa Agostinha’ Settlement Project, Caraúbas-RN, Brazil. Five areas were defined for study in the soil/landscape relation: i) area with cashew cultivation; ii) area of pasture; iii) area of crops in consortium; iv) agroforestry; and v) preserved forest, used as the reference. Participatory workshops, exchanges and classifications (from the locals and formal) were carried out with the analysis of the morphological, physical and chemical attributes of the studied soils in the layers of 0.00-0.10, 0.10-0.20 and 0.20-0.30 m. The results of the ethicist classification, based on the attributes evaluation were: Quartzarenic latosol NEOSOL (cashew area); Regolitic euthrofic NEOSOL (pasture area); Ortic quartzarenic fragiudult NEOSOL (intercropping area); typical quartzarenic ortic NEOSOL (agroforestry area and typical hydromorphic quartzarenic NEOSOL that presented a close relation with the emicist classification (from the local people). The observation of the different soil types in the landscape, due to the stratification of the environments, allowed the growers to identify characteristics associated with soil potentials and restrictions and, consequently, the correct management to be adopted. The experiences of local growers in the participatory workshops provided an exchange of popular and scientific knowledge, as well as new perspectives of coexistence with the semiarid.

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Soil Attributes Using Different Agricultural Use Systems in the Rio Grande do Norte Semiarid, Brazil

Journal of Agricultural Science ◽

10.5539/jas.v10n11p190 ◽

2018 ◽

Vol 10 (11) ◽

pp. 190

Author(s):

Ana Karenina Fernandes de Sousa Ribeiro ◽

Jeane Cruz Portela ◽

Rafael Oliveira Batista ◽

Carolina Malala Martins Souza ◽

Joseane Dunga da Costa ◽

...

Keyword(s):

High Salinity ◽

Clay Fraction ◽

Particle Size Analysis ◽

Semiarid Region ◽

Size Analysis ◽

Plasticity Limit ◽

Physical Attributes ◽

Agricultural Use ◽

Chemical Attributes ◽

Physical And Chemical

The semiarid region is extremely fragile to anthropogenic actions. Thus, the objective of this study is to evaluate the physical and chemical attributes of soils with different agricultural uses. The research was carried out in the municipality of Governador Dix-Sept Rosado. Fertility and physical analyses were performed. The results were interpreted by multivariate analysis. The soils that presented a eutrophic character were influenced by lithology. In the Cambissolo (Haplustepts), there was an increase in the limits of liquidity and plasticity due to the increase of the clay fraction and total organic carbon. By the particle size analysis, the profiles presented variations in textural classes. We concluded that the physical attributes moisture, liquidity limit, plasticity limit, clay plasticity index, thin sand and the chemical attributes pH, (H + Al), V and PST were the most sensitive for the distinction of environments. The studied areas presented acidity reactions to alkalinity with presence of Al3+, (H + Al) and high salinity.

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Land use and soil quality in peri-urban farms in Southern Brazil

Pesquisa Agropecuária Gaúcha ◽

10.36812/pag.2021271160-174 ◽

2021 ◽

Vol 27 (1) ◽

pp. 160-174

Author(s):

Agi Costa Cassimo ◽

Paulo César Nascimento ◽

Patrícia Lima De Lima ◽

Carlos Gustavo Tornquist ◽

Carlos Alberto Bissani ◽

...

Keyword(s):

Land Use ◽

Soil Quality ◽

Production Systems ◽

Family Farms ◽

Porto Alegre ◽

Organic Farms ◽

Rural Landscapes ◽

Horticultural Crops ◽

Chemical Attributes ◽

Physical And Chemical

Small family farms constitute a major part of land use in the surrounding regions of Brazilian cities, as these farms not only contribute to the food supply, but also help conserve rural landscapes and improve environmental services. This study evaluated agricultural impacts on soil quality in seven family farms in Porto Alegre municipality, Rio Grande do Sul state, RS. Selected production units (PUs) were managed as conventional or organic farms, producing horticultural crops, fruits and pastures, besides native forests. Soil samples were collected from representative areas for five use and management types, under disturbed and undisturbed conditions, at 0–20 cm depth. Physical and chemical attributes were analyzed, comparing the effects of types of land use. Data analysis showed that more affected attributes were soil density, macro and microporosity, phosphorus content, pH and electrical conductivity. Macroporosity, phosphorus, zinc and cooper contents are the greater threats to soil quality. Horticulture, under both agroecological and conventional production systems caused major changes compared to natural conditions.

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Morphological, physical and chemical attributes of the soil profile to the right margin of the Paraguay river, Baia da Campina, Cáceres (MT)

Scientific Electronic Archives ◽

10.36560/131020201076 ◽

2020 ◽

Vol 13 (10) ◽

pp. 61

Author(s):

A. T. Martins-Oliveira ◽

L. E. S. Stefanello ◽

T. M. Santos ◽

V. R. Pinto ◽

C. A. Souza ◽

...

Keyword(s):

Soil Profile ◽

Geological Structure ◽

Physical Structure ◽

Exchange Capacity ◽

River Channels ◽

Mato Grosso ◽

Paraguay River ◽

Chemical Attributes ◽

The Right ◽

Physical And Chemical

The fluvial dynamics corresponds to the natural changes of river channels that can influence the water energy, type and morphology of the gutter, geological structure and soil types. In this context, the type of soil present on the banks of the rivers stands out, which due to their morphological, physical and chemical characteristics, will offer greater or less resistance to marginal erosive processes. Whit this study, we aim to verify the contribution of soil morphological, physical and chemical attributes in the natural dynamics of the right bank of the Paraguay River. The studied area is located in the Pantanal Matogrossense, sub-region of Cáceres, and comprises the right bank of the Paraguay River, in the region of Baia da Campina, approximately 10 km away from the municipality of Cáceres, Mato Grosso, Brazil. We carry out morphological, granulometric and chemical description of the soil. The data were tabulated in a spreadsheet, being subsequently analyzed and discussed. The vegetation occurring in the study area is of the seasonal / cerrado and alluvial forests type, with the presence of low and semi-shrub vegetation. We classified the soil profile in the section studied as Fluvic Tb Endoeutrophic Neosol, presenting medium texture and, in general, high levels of sand and low levels of clay. The values referring to the effective cation exchange capacity (CTC) obtained in this study, were classified from low to very good, a characteristic that allows the existence of low and semi-shrubby vegetation, which contributes to the resistance to erosive processes, even that the soil has a low presenting resistance physical structure.

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