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Newton La Scala - One of the best experts on this subject based on the ideXlab platform.
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soil carbon dioxide emission associated with soil porosity after sugarcane field reform
Mitigation and Adaptation Strategies for Global Change, 2019Co-Authors: Luma Castro De Souza, Carolina Fernandes, Mara Regina Moitinho, Elton Da Silva Bicalho, Newton La ScalaAbstract:This study aimed to characterize soil carbon dioxide (CO2) emission associated with soil pore distribution in an Oxisol and Ultisol under chiseling in the planting row and in total area for sugarcane (Saccharum officinarum) cultivation. The experimental design was a large paired-plot design. Treatments consisted of chiseling in the planting row (CPR) and chiseling in total area (CTA) in an Oxisol and Ultisol. Soil CO2 emission, soil temperature, and soil moisture were assessed over 12 days in the Oxisol and 11 days in the Ultisol at a depth of 0–0.10 m. Organic carbon associated with minerals (OCAM) and particulate organic carbon (POC) were also assessed. OCAM, pore class C2 (0.05 ≤ ɸ < 0.1 mm), soil moisture, and soil temperature explained 72 and 53% of the variability of soil CO2 emission in CPR and CTA, respectively. In the Ultisol, pore class C1 (ɸ ≥ 0.1 mm) and OCAM explained 82% of the variability of soil CO2 emission in CPR. In CTA, soil moisture, OCAM, and POC explained 67% of the variability of soil CO2 emission. In the Oxisol, CPR and CTA affected soil structure, causing changes in both soil porosity and soil CO2 emission. In the Oxisol, the lowest average value of soil CO2 emission (2.8 μmol m−2 s−1) was observed in CPR whereas its highest value (3.4 μmol m−2 s−1) was observed in CTA. In the Ultisol, soil tillage (CPR and CTA) did not affect soil CO2 emission. These results indicate that the intensity of soil tillage in more clayey textured soils favors soil CO2 emission possibly due to a higher carbon availability for microbial activity when compared to more sandy textured soils. A less intensive soil tillage can be considered as an efficient strategy to reduce soil CO2 emission and hence soil organic carbon losses. Thus, this management strategy proved to be efficient in terms of mitigating greenhouse gas emissions, reducing the contribution of agriculture to global climate change.
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Soil carbon dioxide emission associated with soil porosity after sugarcane field reform
Mitigation and Adaptation Strategies for Global Change, 2019Co-Authors: Luma Castro De Souza, Carolina Fernandes, Mara Regina Moitinho, Elton Bicalho, Newton La ScalaAbstract:This study aimed to characterize soil carbon dioxide (CO_2) emission associated with soil pore distribution in an Oxisol and Ultisol under chiseling in the planting row and in total area for sugarcane ( Saccharum officinarum ) cultivation. The experimental design was a large paired-plot design. Treatments consisted of chiseling in the planting row (CPR) and chiseling in total area (CTA) in an Oxisol and Ultisol. Soil CO_2 emission, soil temperature, and soil moisture were assessed over 12 days in the Oxisol and 11 days in the Ultisol at a depth of 0–0.10 m. Organic carbon associated with minerals (OCAM) and particulate organic carbon (POC) were also assessed. OCAM, pore class C2 (0.05 ≤ ɸ
Luma Castro De Souza - One of the best experts on this subject based on the ideXlab platform.
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soil carbon dioxide emission associated with soil porosity after sugarcane field reform
Mitigation and Adaptation Strategies for Global Change, 2019Co-Authors: Luma Castro De Souza, Carolina Fernandes, Mara Regina Moitinho, Elton Da Silva Bicalho, Newton La ScalaAbstract:This study aimed to characterize soil carbon dioxide (CO2) emission associated with soil pore distribution in an Oxisol and Ultisol under chiseling in the planting row and in total area for sugarcane (Saccharum officinarum) cultivation. The experimental design was a large paired-plot design. Treatments consisted of chiseling in the planting row (CPR) and chiseling in total area (CTA) in an Oxisol and Ultisol. Soil CO2 emission, soil temperature, and soil moisture were assessed over 12 days in the Oxisol and 11 days in the Ultisol at a depth of 0–0.10 m. Organic carbon associated with minerals (OCAM) and particulate organic carbon (POC) were also assessed. OCAM, pore class C2 (0.05 ≤ ɸ < 0.1 mm), soil moisture, and soil temperature explained 72 and 53% of the variability of soil CO2 emission in CPR and CTA, respectively. In the Ultisol, pore class C1 (ɸ ≥ 0.1 mm) and OCAM explained 82% of the variability of soil CO2 emission in CPR. In CTA, soil moisture, OCAM, and POC explained 67% of the variability of soil CO2 emission. In the Oxisol, CPR and CTA affected soil structure, causing changes in both soil porosity and soil CO2 emission. In the Oxisol, the lowest average value of soil CO2 emission (2.8 μmol m−2 s−1) was observed in CPR whereas its highest value (3.4 μmol m−2 s−1) was observed in CTA. In the Ultisol, soil tillage (CPR and CTA) did not affect soil CO2 emission. These results indicate that the intensity of soil tillage in more clayey textured soils favors soil CO2 emission possibly due to a higher carbon availability for microbial activity when compared to more sandy textured soils. A less intensive soil tillage can be considered as an efficient strategy to reduce soil CO2 emission and hence soil organic carbon losses. Thus, this management strategy proved to be efficient in terms of mitigating greenhouse gas emissions, reducing the contribution of agriculture to global climate change.
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Soil carbon dioxide emission associated with soil porosity after sugarcane field reform
Mitigation and Adaptation Strategies for Global Change, 2019Co-Authors: Luma Castro De Souza, Carolina Fernandes, Mara Regina Moitinho, Elton Bicalho, Newton La ScalaAbstract:This study aimed to characterize soil carbon dioxide (CO_2) emission associated with soil pore distribution in an Oxisol and Ultisol under chiseling in the planting row and in total area for sugarcane ( Saccharum officinarum ) cultivation. The experimental design was a large paired-plot design. Treatments consisted of chiseling in the planting row (CPR) and chiseling in total area (CTA) in an Oxisol and Ultisol. Soil CO_2 emission, soil temperature, and soil moisture were assessed over 12 days in the Oxisol and 11 days in the Ultisol at a depth of 0–0.10 m. Organic carbon associated with minerals (OCAM) and particulate organic carbon (POC) were also assessed. OCAM, pore class C2 (0.05 ≤ ɸ
Virupax C. Baligar - One of the best experts on this subject based on the ideXlab platform.
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Chapter 7 Ameliorating Soil Acidity of Tropical Oxisols by Liming For Sustainable Crop Production
Advances in Agronomy, 2008Co-Authors: N. K. Fageria, Virupax C. BaligarAbstract:The greatest potential for expanding the world's agricultural frontier lies in the savanna regions of the tropics, which are dominated by Oxisols. Soil acidity and low native fertility, however, are major constraints for crop production on tropical Oxisols. Soil acidification is an ongoing natural process which can be enhanced by human activities or can be controlled by appropriate soil management practices. Acidity produces complex interactions of plant growth-limiting factors involving physical, chemical, and biological properties of soil. Soil erosion and low water-holding capacity are major physical constraints for growing crops on tropical Oxisols. Calcium, magnesium, and phosphorous deficiencies or unavailabilities and aluminum toxicity are considered major chemical constraints that limit plant growth on Oxisols. Among biological properties, activities of beneficial microorganisms are adversely affected by soil acidity, which has profound effects on the decomposition of organic matter, nutrient mineralization, and immobilization, uptake, and utilization by plants, and consequently on crop yields. Liming is a dominant and effective practice to overcome these constraints and improve crop production on acid soils. Lime is called the foundation of crop production or "workhorse" in acid soils. Lime requirement for crops grown on acid soils is determined by the quality of liming material, status of soil fertility, crop species and cultivar within species, crop management practices, and economic considerations. Soil pH, base saturation, and aluminum saturation are important acidity indices which are used as a basis for determination of liming rates for reducing plant constraints on acid soils. In addition, crop responses to lime rate are vital tools for making liming recommendations for crops grown on acid soils. The objective of this chapter is to provide a comprehensive and updated review of lime requirements for improved annual crop production on Oxisols. Experimental data are provided, especially for Brazilian Oxisols, to make this review as practical as possible for improving crop production. © 2008 Elsevier Inc. All rights reserved.
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chapter 7 ameliorating soil acidity of tropical Oxisols by liming for sustainable crop production
Advances in Agronomy, 2008Co-Authors: N. K. Fageria, Virupax C. BaligarAbstract:Abstract The greatest potential for expanding the world's agricultural frontier lies in the savanna regions of the tropics, which are dominated by Oxisols. Soil acidity and low native fertility, however, are major constraints for crop production on tropical Oxisols. Soil acidification is an ongoing natural process which can be enhanced by human activities or can be controlled by appropriate soil management practices. Acidity produces complex interactions of plant growth‐limiting factors involving physical, chemical, and biological properties of soil. Soil erosion and low water‐holding capacity are major physical constraints for growing crops on tropical Oxisols. Calcium, magnesium, and phosphorous deficiencies or unavailabilities and aluminum toxicity are considered major chemical constraints that limit plant growth on Oxisols. Among biological properties, activities of beneficial microorganisms are adversely affected by soil acidity, which has profound effects on the decomposition of organic matter, nutrient mineralization, and immobilization, uptake, and utilization by plants, and consequently on crop yields. Liming is a dominant and effective practice to overcome these constraints and improve crop production on acid soils. Lime is called the foundation of crop production or “workhorse” in acid soils. Lime requirement for crops grown on acid soils is determined by the quality of liming material, status of soil fertility, crop species and cultivar within species, crop management practices, and economic considerations. Soil pH, base saturation, and aluminum saturation are important acidity indices which are used as a basis for determination of liming rates for reducing plant constraints on acid soils. In addition, crop responses to lime rate are vital tools for making liming recommendations for crops grown on acid soils. The objective of this chapter is to provide a comprehensive and updated review of lime requirements for improved annual crop production on Oxisols. Experimental data are provided, especially for Brazilian Oxisols, to make this review as practical as possible for improving crop production.
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Response of upland rice and common bean to liming on an Oxisol
Plant-Soil Interactions at Low pH, 1991Co-Authors: N. K. Fageria, Virupax C. Baligar, R. J. Wright, J. R. P. CarvalhoAbstract:Liming is an important cultural practice to improve crop productivity on acid soils. The objectives of this study were to evaluate the response of upland rice (Oryza sativa L.) and common bean (Phaseolus vulgaris L.) to liming on an Oxisol (Typic Haplustox) and to monitor chemical property changes in the soil profile. Dolomitic lime was applied at rates of 0, 3, 6, 9, and 12 metric tons ha−1. Upland rice was less responsive than common bean to lime addition. Upland rice dry matter and grain yields increased up to 32 and 19%, respectively, with lime addition. Liming increased common bean dry matter production up to 40% and grain yield up to 45%. Plow-layer addition of dolomitic limestone resulted in significant downward movement of Ca and Mg into the subsoil and improved subsoil acidity conditions. These results confirm that surface application dolomitic lime can partially ameliorate subsoil acidity in Brazilian Oxisols.
Guangxi Xing - One of the best experts on this subject based on the ideXlab platform.
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the effects of rice straw biochar addition on nitrification activity and nitrous oxide emissions in two Oxisols
Soil & Tillage Research, 2016Co-Authors: Lili He, Xu Zhao, Shenqiang Wang, Guangxi XingAbstract:Nitrification rates in Oxisols vary with soil pH and substrate availability. Biochar can be used to improve acid soils. The aim of this study was therefore to investigate the interactive impacts of 1% and 5% (w/w) rice-straw biochar application on nitrification, ammonia oxidizer populations and nitrous oxide (N2O) emissions over short periods of microcosm incubation in two agricultural Oxisols derived from granite (RGU) and tertiary red sandstone (RTU), respectively. We measured soil nitrate (NO3−) and ammonium (NH4+) concentrations during the incubation and used nitrification kinetic model to assess the response of nitrification to biochar addition. We also performed real-time quantitative polymerase chain reaction (qPCR) to quantify the copies of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) genes, and collected N2O gas at various intervals during the 56-day incubation. The addition of ammonium sulfate ((NH4)2SO4-N) stimulated nitrification in both soils. In RGU, biochar treatments altered soil nitrification patterns to a first-order reaction model; this stimulation was more pronounced with the increase of biochar application rates. In RTU, 1% biochar treatment increased nitrification rate constants, and 5% biochar treatment altered nitrification patterns from a zero-order to a first-order reaction model. Treating the two soils with 5% biochar rates significantly increased AOB gene copy numbers up to 7.88- and 14-fold compared with the no biochar controls in RGU and RTU, respectively, while the treatments had little or reduced effect on AOA gene copy numbers. Biochar addition significantly reduced cumulative N2O emissions up to 37.6% in RGU and 46.4% in RTU, respectively. These results underscore the potential of biochar in the restoration of nitrification and the reduction of greenhouse gas N2O emission in Oxisols.
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comparison of straw biochar mediated changes in nitrification and ammonia oxidizers in agricultural Oxisols and cambosols
Biology and Fertility of Soils, 2016Co-Authors: Lili He, Jin Zhao, Yucui Bi, Xu Zhao, Shenqiang Wang, Guangxi XingAbstract:The responses of nitrification on intensively managed agricultural soils following long-term biochar (BC) amendment are poorly understood. The nitrification potential, abundance, and composition of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in acidic Oxisols and alkaline cambosols following a 3-year BC treatment were investigated using 42-day aerobic incubation, quantitative polymerase chain reaction (qPCR), and clone library approach, respectively. Fresh soils were collected from a wheat/millet rotated pot trial in which 0 (control), 2.25, and 22.5 Mg ha−1 rice straw BCs were added for six consecutive crop seasons. The 22.5 Mg ha−1 BC (BC22.5) treatment enhanced nitrification in Oxisols and even altered nitrification pattern from zero-order to first-order reaction model. AOA and AOB gene copies in the BC22.5 treatment were 9.55 and 22.0 times, respectively, compared with those in the BC0 treatment. The relative abundance of operational taxonomic units (OTUs) in AOA group 1.1a changed due to BC application, and that of OTU-20 was high in group 1.1b-related under the BC22.5 treatment. AOB community composition shifted toward Nitrosospira cluster 3 and 3-related group under the BC22.5 treatment. Basal nitrification was already high in cambosols, and BC had minimal effect on nitrification or AOA/AOB abundance. However, the BC22.5 treatment increased the relative abundance of OTU-9 in Nitrosospira cluster 3 group and that of OTU-13 and OTU-16 in Nitrosospira cluster 3-related groups both being AOB. The BC amendment had minimal effect on ammonia oxidizer composition in cambosols but influenced ammonia oxidizer composition and stimulated nitrification activity in Oxisols.
Carlos Clemente Cerri - One of the best experts on this subject based on the ideXlab platform.
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effect of grassland management on soil carbon sequestration in rondonia and mato grosso states brazil
Geoderma, 2009Co-Authors: Stoecio Malta Ferreira Maia, Stephen M Ogle, Carlos Eduardo Pellegrino Cerri, Carlos Clemente CerriAbstract:Abstract Grassland management affects soil organic carbon (SOC) content and a variety of management options have been proposed to sequester carbon. However, studies conducted in Brazilian pastures have shown divergent responses for the SOC depending on management practices. Our objective was to evaluate the effects of management on SOC stocks in grasslands of the Brazilian states of Rondonia and Mato Grosso, and to derive region-specific factors for soil C stock change associated with different management conditions. Compared to SOC stocks in native vegetation, degraded grassland management decreased SOC by a factor of 0.91 ± 0.14, nominal grassland management reduced SOC stock for Oxisols by a relatively small factor of 0.99 ± 0.08, whereas, SOC storage increased by a factor of 1.24 ± 0.07 with nominal management for other soil types. Improved grassland management on Oxisols increased SOC storage by 1.19 ± 0.07, relative to native stocks, but there were insufficient data to evaluate the impact of improved grassland management for other soil types. Using these results, we also evaluated the potential for grassland management to sequester or emit C to the atmosphere, and found that degraded grassland management decreased stocks by about 0.27–0.28 Mg C ha− 1 yr− 1; nominal management on Oxisols decreased C at a rate of 0.03 Mg C ha− 1 yr− 1, while nominal management on others soil types and improved management on Oxisols increased stocks by 0.72 Mg C ha− 1 yr− 1 and 0.61 Mg C ha− 1 yr− 1, respectively. Therefore, when well managed or improved, grasslands in Rondonia and Mato Grosso states have the potential to sequester C.
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modeling vertical distribution of carbon in Oxisols of the western brazilian amazon rondonia
Soil Science, 1998Co-Authors: Martial Bernoux, Carlos Clemente Cerri, Dominique Arrouays, Hocine BourennaneAbstract:Oxisols have great ecological significance in tropical soils because they are the dominant soil type of the Brazilian Amazon ecosystem, comprising more than 40% of its total. To estimate carbon (C) stocks and changes requires knowledge of the vertical distribution of C in profiles. The objective of this study was to determine if specific patterns occur in C profiles of Oxisols in the Western Brazilian Amazon so that total C storage can be assessed down to any given depth by simple models with low input data requirements. Two models, a power-based model and an exponential-based model, were tested using nonlinear regression analysis on a soil database made up of 129 Oxisol profiles corresponding to 519 soil horizons. These models, as judged by the coefficient of determination (R 2 ) value, explained more than 55% of the total variance for all of the horizons, whether or not segregated by taxonomic unit. The models were then tested with individual profiles. The power model exhibited a tendency to overestimate C stocks when integration was done for the 0-20-cm and the 0-100-cm layers. Results from the exponential model were better than those from the power model. The R 2 values were greater than 0.82, and the associated standard error was reduced. In a validation procedure, the mean error (ME) was close to zero for the exponential model, with a systematic ME of only 0.06 kg C.m -2 for the 0-100-cm layer.
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Soil microbial biomass in Amazonian soils: Evaluation of methods and estimates of pool sizes
Soil Biology and Biochemistry, 1995Co-Authors: Brigitte Josefine Feigl, D J Ross, G. P. Sparling, Carlos Clemente CerriAbstract:The suitability of the fumigation-incubation (FI), fumigation-extraction (FE) (with specific k-factor determined by14C-labelling) and substrate induced respiration (SIR) methods to obtain measures of the microbial biomass in forest soils from the Amazonian basin was examined. Several representitive topsoil (0-10 cm) samples were studied. A reasonable estimate of microbial biomass C in two acid Oxisols (pH
