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| Registros recuperados: 74 | |
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| Gontijo,Ivoney; Souza Dias Junior,Moacir de; Guimarães,Paulo Tácito Gontijo; Oliveira,Marcelo Silva de; Ajayi,Ayodele Ebenezer. |
| Information on the spatial structure of soil physical and structural properties is needed to evaluate the soil quality. The purpose of this study was to investigate the spatial behavior of preconsolidation pressure and soil moisture in six transects, three selected along and three across coffee rows, at three different sites under different tillage management systems. The study was carried out on a farm, in Patrocinio, state of Minas Gerais, in the Southeast of Brazil (18 º 59 ' 15 '' S; 46 º 56 ' 47 '' W; 934 m asl). The soil type is a typic dystrophic Red Latosol (Acrustox) and consists of 780 g kg-1 clay; 110 g kg-1 silt and 110 g kg-1 sand, with an average slope of 3 %. Undisturbed soil cores were sampled at a depth of 0.10-0.13 m, at three different... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Semivariogram; Soil compaction; Geostatistics; Soil sampling. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000400012 |
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| Cortez,Jorge W.; Lopes,Hélio L.; Coelho,Daniela S.; Arcoverde,Sálvio N. S.. |
| Since the advent of mechanized farming and intensive use of agricultural machinery and implements on the properties, the soil began to receive greater load of machinery traffic, which can cause increased soil compaction. The aim of this study was to evaluate the spatial variability of soil mechanical resistance to penetration (RP) in the layers of 0.00-0.10, 0.10-0.20, 0.20-0.30 and 0.30-0.40m, using geostatistics in an area cultivated with mango in Haplic Vertisol of the northeastern semi-arid, with mobile unit equipped with electronic penetrometer. The RP data was collected in 56 points from an area of 3 ha, and random soil samples were collected to determine the soil moisture and texture. For RP data analysis we used descriptive statistics and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil compaction; Machinery traffic; Agricultural mechanization. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000200006 |
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| Bonnin,Juan José; Mirás-Avalos,José Manuel; Lanças,Kléber Pereira; González,Antonio Paz; Vieira,Sidney Rosa. |
| The aim of this work was to analyze the spatial distribution of soil compaction and the influence of soil water content on the resistance to penetration. The latter variable was described by the cone index. The soil at the study site was a Nitisol and the cone index data were obtained using a penetrometer. Soil resistance was assessed at 5 different depths, i.e. 0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm and deeper than 40 cm, whereas soil water content was measured at 0-20 cm and 20-40 cm. Soil water conditions varied during the different samplings. Coefficients of variation for cone index ranged from 16.5% to 45.8% while those for soil water content varied from 8.96% to 21.38%. Results suggested a high correlation between soil resistance, as assessed by the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cone index; Indicator kriging; Soil compaction; Spatial distribution. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500017 |
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| Feitosa,Izabela de Lima; Passos,Alexandre Martins Abdão dos; Cipriani,Henrique Nery; Oliveira,Marcelo Silva de; Marcolan,Alaerto Luiz; Vasques,Gustavo Mattos. |
| Abstract: The objective of this work was to analyze the spatial variability of soil physical attributes in integrated production systems and its relationship with the growth and yield of a corn (Zea mays) crop intercropped with palisade grass (Urochloa brizantha). The experiment was carried out in an integrated crop-livestock (ICL) system and in an integrated crop-livestock-forestry (ICLF) system, in a Plinthic Hapludox. The ICLF system was managed in alleys between eucalyptus (Eucalyptus spp.) rows, spaced at 18, 30, and 42 m. Corn grain and forage yields were positively correlated with soil clay and moisture contents, whereas grain yield was negatively correlated with soil penetration resistance. The lowest corn plant heights and grain yields were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eucalyptus; Urochloa brizantha; Agronomic efficiency; Precision agriculture; Soil compaction; Soil variability. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2019000100600 |
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| Severiano,Eduardo da Costa; Oliveira,Geraldo César de; Dias Júnior,Moacir de Souza; Costa,Katia Aparecida de Pinho; Silva,Fabiano Guimarães; Ferreira Filho,Silvio Marcos. |
| The agricultural potential of Latosols of the Brazilian Cerrado region is high, but when intensively cultivated under inappropriate management systems, the porosity can be seriously reduced, leading to rapid soil degradation. Consequently, accelerated erosion and sedimentation of springs and creeks have been observed. Therefore, the objective of this study was to evaluate structural changes of Latosols in Rio Verde, Goiás, based on the Least Limiting Water Range (LLWR), and relationships between LLWR and other physical properties. Soil samples were collected from the B horizons of five oxidic Latosols representing the textural variability of the Latosols of the Cerrado biome. LLWR and other soil physical properties were determined at various soil... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil compaction; Degradation of agricultural soils; Soil penetration resistance; Water availability; Soil texture. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000300013 |
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| Silva,Sâmala Glícia Carneiro; Silva,Álvaro Pires da; Giarola,Neyde Fabíola Balarezo; Tormena,Cássio Antônio; Sá,João Carlos de Moraes. |
| Mechanical chiseling has been used to alleviate the effects of compaction in soils under no-tillage (NT). However, its effect on the soil physical properties does not seem to have a defined duration period. The purpose of this study was to evaluate the behavior of the bulk density (BD) and degree of compaction (DC) at different soil depths, after chiseling in no-tillage, for one year. The experiment was performed in Ponta Grossa, Paraná State, Brazil, using an Oxisol (Rhodic Hapludox). Bulk density and DC were previously measured in an area under NT for 16 years, then immediately after chiseling (CHI) in May 2009, six months after chiseling (CHI6M) in October 2009 and one year after chiseling (CHI12M) in May 2010. In the layers 0.0-0.10, 0.10-0.20 and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil compaction; Structure; Soil quality; Resilience. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000200024 |
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| Pereira,Tonismar dos S.; Robaina,Adroaldo D.; Peiter,Marcia X.; Torres,Rogerio R.; Bruning,Jhosefe. |
| ABSTRACT The aim of this study was to present and to evaluate methodologies for the estimation of soil resistance to penetration (RP) using artificial intelligence prediction techniques. In order to do so, a data base with values of physical-water characteristics of the soils available in the literature was used, and the performances of Artificial Neural Networks (ANN) and Support Vector Machines (SVM) were evaluated. The models generated from the ANNs were implemented through the multilayer perceptron with backpropagation algorithm of Matlab software, varying the number of neurons in the input and intermediate layers. For the procedure from SVM, the RapidMiner software was used, varying input variables, the kernel function and the coefficients of these... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil compaction; Machine learning; Support vector machines; Artificial neural networks. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000100142 |
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| Zulpo,Lucas; Kerpen,Hyran Stefanowski; Fink,Jefferson Antonio; Mazurana,Michael; Levien,Renato. |
| Abstract: The objective of this work was to evaluate the impact of different furrow-opening mechanisms on soil physical characteristics, such as mobilization, porosity, bulk density, and the dynamics of water content and temperature in the sowing groove, as well as the influence of wheeled traffic and of these variables on corn (Zea mays) productivity. The experiment was conducted at the agronomic experimental station of Universidade Federal do Rio Grande do Sul on a Argissolo Vermelho (red Ultisol). Treatments consisted of three winter cover crops and of two types of furrow-opening mechanisms for fertilization (shank and disk), with or without tractor traffic. Corn was planted as the summer crop, and soil mobilization in the sowing groove, soil... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Zea mays; No-tillage system; Furrow-opening mechanisms; Soil compaction; Soil temperature. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2019000103804 |
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| Moraes,Moacir T. de; Silva,Vanderlei R. da; Zwirtes,Anderson L.; Carlesso,Reimar. |
| Soil physical quality can be easily and quickly evaluated by using simple equipment to identify levels of soil compaction. Hence, it is necessary to know the variables responsible for changes in the soil penetration resistance (SPR). The aim of this review is to identify the main factors related to the various equipment used for assessing SPR as a soil physical quality indicator in agriculture. This literature review describes the different types of equipment used and its relationship with SPR. A wide range of procedures, devices, and equipments are available. Much of variability in SPR results is related to the equipment model, cone angle and diameter, and penetration rate. Usually, restrictions to root growth are correlated with SPR values above 2-3 MPa.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil compaction; Soil physics; Physical quality; Penetrometry. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000100019 |
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| CRISTIANO,ZERBATO; COMPAGNON,ARIEL M.; VOLTARELLI,MURILO A.; ROSALEN,DAVID L.; FURLANI,CARLOS E. A.. |
| ABSTRACT The mechanical resistance to penetration when related to the water content is an indicator often used of soil compaction, the use of positioning methods for greater accuracy of this review is important. In this context, this study aimed to determine the variability of positioning methods provided by GPS receivers to determine the spatial behavior of physical attributes related to soil compaction. The study area is located in the municipality of Jaboticabal, around the latitude 21º15’22”S and longitude 48º18’58”W, being characterized with a clayey Oxisol. The variables used as parameters of soil physical properties were the mechanical resistance to penetration and water content, using a sampling grid of 20 x 20 m, totaling 60 points. We used six... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: GPS; Penetrometer; Soil compaction; Soil water content. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162016000400696 |
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| Costa,Larissa F.; Balbinot Antonino,Antonio C. D.; Richard J.,Heck; Coutinho,Artur P.; Vasconcelos,Thiago C.; Machado,Cassia B.. |
| ABSTRACT Analysis of shapes, sizes, continuity, orientation and irregularities of pores can help in the study of soil structural modifications induced by soil management. The study of the inter- and intra-aggregate porous space of urban and rural soils by tomographic images is the objective of this work. A morphometric characterization of the pores was carried out with the analysis of distribution of their size, shape and inclination in these two types of soil. The urban soil showed smaller percentage of inter-aggregate voids and more intra-aggregate voids compared with the rural soil. The cumulative distribution of void volumes showed little pore diversity in the urban soil and great presence of large pores (48%), almost twice the voids with same size in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Porosity; Tomographic images; Soil compaction. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000400249 |
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| 全, 亨奎; 谷口, 哲司; 大友, 功一; 岸本, 正; 大山, 毅; JUN, Hyung-gyu; TANIGUCHI, Tetsuji; OHTOMO, Ko-ichi; KISHIMOTO, Tadashi; OHYAMA, Tsuyoshi. |
| タイヤ性能を改善し土壌踏圧を解明するための基礎研究として, タイヤ変形を考慮しての接地面積計測方法を確立した。走行時のタイヤ断面形状を楕円で近似し, タイヤのラジアル方向および横方向変形量, 沈下量, 踏面長さ等の測定値から, タイヤ走行時の3次元接地面積を求めた。また, レーザセンサ距離計により土壌面上部定位置から踏圧面までの距離をメッシュ状に測定できる土壌変形計測装置を開発し, タイヤ静荷重時の3次元接地面積を求めた。これより, 静荷重時接地面積は走行時の約1.3倍となった。さらに, 同装置により静荷重時の土壌深さの違いによる土壌変形量を測定した。その結果, 変形前の土壌の10cmより浅い土壌層にラグによる土壌変形がみられた。 Methods for the determination of 3-D contact area between a tire and soil were presented to improve tire performance and to clarify soil compaction. The contact area during tire operation on the soil was calculated with radial，lateral and longitudinal deflections of the tire and the sinkage. The device with a laser sensor was developed to measure the distances from a fixed position to soil surface for the calculation of contact area under... |
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Palavras-chave: タイヤ変形; 土壌踏圧; 接地面積; 土壌変形; 空気圧; トラクタタイヤ; ラジアルタイヤ; Tire deformation; Soil compaction; Contact area; Soil deformation; Inflation pressure; Agricultural tractor. |
| Ano: 1997 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2952 |
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| 全, 亨奎; 谷口, 哲司; 大友, 功一; 岸本, 正; 玉利, 達人; JUN, Hyung-gyu; TANIGUCHI, Tetsuji; OHTOMO, Ko-ichi; KISHIMOTO, Tadashi; TAMARI, Tatsuto. |
| 6個の圧力センサを利用して耕盤での土中応力状態を測定可能な土中応力測定器 (以下測定器) を開発した。測定器をタイヤ進行方向のタイヤ中心部およびタイヤ側端のラグ直下ならびにタイヤ側端のアンダートレッド直下の3ヶ所に土壌表面から深さ25cmの耕盤上に埋設し, タイヤを走行させて土中応力を測定した。得られたデータから応力状態を算出し, 主応力を求めた。次に, 測定器の埋設位置の違いによる最大主応力を検討した。その結果, タイヤ中心部ラグ直下における最大主応力が, タイヤ側端部でのそれの2倍以上になっていることが分かった。 A transducer was developed to determine the stress state in the soil on a hard pan. Principal stresses， octahedral normal and shearing stresses can be calculated from the data measured with six pressure cells on the transducer in the six predetermined directions. The transducer was buried in three locations in the soil at 25cm depth : under the lug at the centerline and the edge of the tire and under the undertread at the edge of the tire. The effect of changes in the locations of buried transducer... |
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Palavras-chave: 土壌踏圧; 動荷重; 空気圧; 土中応力; 応力テンソル; 農用タイヤ; ラジアルタイヤ; Soil compaction; Dynamic load; Inflation pressure; Soil stress; Stress tensor; Agricultural tractor tire; Radial tire. |
| Ano: 1997 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2950 |
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| Registros recuperados: 74 | |
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