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James V. Wallace - One of the best experts on this subject based on the ideXlab platform.
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Soil nitrogen conservation with continuous no-till management
Nutrient Cycling in Agroecosystems, 2008Co-Authors: John T. Spargo, Marcus M. Alley, Ronald F. Follett, James V. WallaceAbstract:Tillage management is an important regulator of organic matter decomposition and N mineralization in agroecosystems. Tillage has resulted in the loss of considerable organic N from surface soils. There is potential to rebuild and conserve substantial amounts of soil N where no-till management is implemented in crop production systems. The objectives of our research were to measure N conservation rate with continuous no-till management of grain cropping systems and evaluate its impact on mineralizable and inorganic soil N. Samples were collected from 63 sites in production fields using a rotation of corn (Zea mays L.)—wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.)—double-crop soybean (Glysine max L.) across three soil series [Bojac (Coarse-loamy, mixed, semiactive, thermic Typic Hapludults), Altavista (Fine-loamy, mixed semiactive, thermic Aquic Hapludults), and Kempsville (Fine-loamy, siliceous, subactive, thermic Typic Hapludults)] with a history of continuous no-till that ranged from 0 to 14 yrs. Thirty-two of the sites had a history of biosolids application. Soil cores were collected at each site from 0–2.5, 2.5–7.5 and 7.5–15 cm and analyzed for total N, Illinois soil N test-N (ISNT-N), and [NH4 + NO3]-N. A history of biosolids application increased the concentration of total soil N by 154 ± 66.8 mg N kg−1 (310 ± 140 kg N ha−1) but did not increase ISNT-N in the surface 0 – 15 cm. Continuous no-till increased the concentration of total soil N by 9.98 mg N kg−1 year−1 (22.2 ± 21.2 kg N ha−1 year−1) and ISNT-N by 1.68 mg N kg−1 year−1 in the surface 0–15 cm. The implementation of continuous no-till management in this cropping system has resulted in conservation of soil N.
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Soil carbon sequestration with continuous no-till management of grain cropping systems in the Virginia coastal plain
Soil & Tillage Research, 2008Co-Authors: John T. Spargo, Marcus M. Alley, Ronald F. Follett, James V. WallaceAbstract:Carbon sequestration in agroecosystems represents a significant opportunity to offset a portion of anthropogenic CO2 emissions. Climatic conditions in the Virginia coastal plain and modern production practices make it possible for high annual photosynthetic CO2 fixation. There is potential to sequester a substantial amount of C, and concomitantly improve soil quality, with the elimination of tillage for crop production in this region. The objectives of our research were to: (1) measure C sequestration rate with continuous no-till management of grain cropping systems of the Virginia middle coastal plain; (2) determine the influence of biosolids application history on C content and its interaction with tillage management; and (3) evaluate the impact of continuous no-till C stratification as an indicator of soil quality. Samples were collected from 63 sites in production fields using a rotation of corn (Zea mays L.)- wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.)/soybean double-crop (Glysine max L.) across three soil series (Bojac (coarse-loamy, mixed, semiactive, thermic Typic Hapludults), Altavista (fine- loamy, mixed semiactive, thermic Aquic Hapludults), and Kempsville (fine-loamy, siliceous, subactive, thermic Typic Hapludults)) with a history of continuous no-till management ranging from 0 to 14 years. Thirty-two of the sites had a history of biosolids application. Five soil cores were collected at each site from 0-2.5, 2.5-7.5 and 7.5-15 cm and analyzed for bulk density and soil C. Bulk density in the 0-2.5 cm layer decreased and C stratification ratio (0-2.5 cm:7.5-15 cm) increased with increasing duration of continuous no-till due to the accumulation of organic matter at the soil surface. A history of biosolids application resulted in an increase of 4.19 1.93 Mg C ha 1
John T. Spargo - One of the best experts on this subject based on the ideXlab platform.
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Soil nitrogen conservation with continuous no-till management
Nutrient Cycling in Agroecosystems, 2008Co-Authors: John T. Spargo, Marcus M. Alley, Ronald F. Follett, James V. WallaceAbstract:Tillage management is an important regulator of organic matter decomposition and N mineralization in agroecosystems. Tillage has resulted in the loss of considerable organic N from surface soils. There is potential to rebuild and conserve substantial amounts of soil N where no-till management is implemented in crop production systems. The objectives of our research were to measure N conservation rate with continuous no-till management of grain cropping systems and evaluate its impact on mineralizable and inorganic soil N. Samples were collected from 63 sites in production fields using a rotation of corn (Zea mays L.)—wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.)—double-crop soybean (Glysine max L.) across three soil series [Bojac (Coarse-loamy, mixed, semiactive, thermic Typic Hapludults), Altavista (Fine-loamy, mixed semiactive, thermic Aquic Hapludults), and Kempsville (Fine-loamy, siliceous, subactive, thermic Typic Hapludults)] with a history of continuous no-till that ranged from 0 to 14 yrs. Thirty-two of the sites had a history of biosolids application. Soil cores were collected at each site from 0–2.5, 2.5–7.5 and 7.5–15 cm and analyzed for total N, Illinois soil N test-N (ISNT-N), and [NH4 + NO3]-N. A history of biosolids application increased the concentration of total soil N by 154 ± 66.8 mg N kg−1 (310 ± 140 kg N ha−1) but did not increase ISNT-N in the surface 0 – 15 cm. Continuous no-till increased the concentration of total soil N by 9.98 mg N kg−1 year−1 (22.2 ± 21.2 kg N ha−1 year−1) and ISNT-N by 1.68 mg N kg−1 year−1 in the surface 0–15 cm. The implementation of continuous no-till management in this cropping system has resulted in conservation of soil N.
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Soil carbon sequestration with continuous no-till management of grain cropping systems in the Virginia coastal plain
Soil & Tillage Research, 2008Co-Authors: John T. Spargo, Marcus M. Alley, Ronald F. Follett, James V. WallaceAbstract:Carbon sequestration in agroecosystems represents a significant opportunity to offset a portion of anthropogenic CO2 emissions. Climatic conditions in the Virginia coastal plain and modern production practices make it possible for high annual photosynthetic CO2 fixation. There is potential to sequester a substantial amount of C, and concomitantly improve soil quality, with the elimination of tillage for crop production in this region. The objectives of our research were to: (1) measure C sequestration rate with continuous no-till management of grain cropping systems of the Virginia middle coastal plain; (2) determine the influence of biosolids application history on C content and its interaction with tillage management; and (3) evaluate the impact of continuous no-till C stratification as an indicator of soil quality. Samples were collected from 63 sites in production fields using a rotation of corn (Zea mays L.)- wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.)/soybean double-crop (Glysine max L.) across three soil series (Bojac (coarse-loamy, mixed, semiactive, thermic Typic Hapludults), Altavista (fine- loamy, mixed semiactive, thermic Aquic Hapludults), and Kempsville (fine-loamy, siliceous, subactive, thermic Typic Hapludults)) with a history of continuous no-till management ranging from 0 to 14 years. Thirty-two of the sites had a history of biosolids application. Five soil cores were collected at each site from 0-2.5, 2.5-7.5 and 7.5-15 cm and analyzed for bulk density and soil C. Bulk density in the 0-2.5 cm layer decreased and C stratification ratio (0-2.5 cm:7.5-15 cm) increased with increasing duration of continuous no-till due to the accumulation of organic matter at the soil surface. A history of biosolids application resulted in an increase of 4.19 1.93 Mg C ha 1
Sung Won Yoon - One of the best experts on this subject based on the ideXlab platform.
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Deep subsoiling of a subsurface-compacted typical hapludult under citrus orchard
Revista Brasileira de Ciência do Solo, 2013Co-Authors: João Carlos Medeiros, Getulio Coutinho Figueiredo, Álvaro Luiz Mafra, Jaqueline Dalla Rosa, Sung Won YoonAbstract:Soil management practices which increase the root depth penetration of citrus are important to the longevity and yield maintenance of this plant, especially in regions where long periods of drought are common, even in soil conventionally subsoiled to a depth of 30-40 cm, when the orchard was first established. The objective of this study was to evaluate the efficiency of subsoiling on the physical and hydric properties of a Typical Hapludult and fruit yield in a 14-year-old citrus orchard located in Piracicaba, SP. The treatments consisted of: no-subsoiling (with no tilling of the soil after the orchard was planted); subsoiling on one side of the plant lines (SUB. 1); and subsoiling on both sides of the plant lines (SUB. 2). The subsoiling treatments were carried out 1.5 m from the plant lines and to a depth of 0.8 m. Soil samples were taken 120 days after this operation, at four depths, in order to determine physical and hydric properties. Fruit yield was evaluated 150 days after subsoiling. Subsoiling between the plant lines of an old established citrus orchard alters the physical and hydric properties of the soil, which is reflected in increased soil macroporosity and unsaturated hydraulic conductivity, and reduced soil bulk density, critical degree-of-compactness and penetration resistance. The improvements in the physical and hydric properties of the soil were related to an increase in fruit number and orchard yield.
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Morphology, lacunarity and entropy of intra-aggregate pores: Aggregate size and soil management effects
Geoderma, 2008Co-Authors: Hyen-chung Chun, Daniel Giménez, Sung Won YoonAbstract:Abstract In a hierarchical model of soil structure, small size aggregates are less porous and contain smaller pores than larger aggregates. Fractal dimensions obtained from aggregate mass-ratio data seem to confirm a hierarchical organization of intra-aggregate pores that may be altered by tillage. The objective of this study was to use image analysis to directly characterize the morphology and spatial arrangement of intra-aggregate pores as a function of aggregate size and soil management. The surfaces of wooded and cultivated sites of a Typic Hapludults, an Aquic Hapludults and an Ultic Hapludalfs were sampled. Hand-picked aggregates from each site were separated in three size groups having masses of 5–6 g ( M 5 ), 2 g ( M 2 ) and 0.5 g ( M 0.5 ) and 6 aggregates per size group were resin-impregnated and imaged. Measurements on the 108 images included pore shape (planar, irregular and rounded), the geometric mean of the Feret (longest) pore diameter (GMFD) for each shape group and pores greater than 300 μm 2 , and properties of the spatial arrangement of pores characterized with a normalized entropy and a lacunarity function. Distributions of GMFD by shape were quantified with the Kullback–Leibler Divergence and a chi-square test. Planar pores had greater GMFD values than irregular and rounded pores and their distributions were significantly different ( P P M 0.5 than in the M 5 and M 2 size groups (entropy function only) and 2) correlated to the porosity, pore number and to GMFD (entropy function only) values of each pore shape group. The lacunarity function revealed a fractal or multifractal structure of pores within aggregates, while the normalized entropy function detected significantly lower entropy in aggregates of the M 0.5 size group. The GMFD of planar pores showed well defined trends with fractal parameters obtained from data (reported elsewhere) on aggregate mass-ratio. These results are evidence of differences in the organization and distribution of pores within aggregates of different sizes that may be of a hierarchical (fractal) type.
Marcus M. Alley - One of the best experts on this subject based on the ideXlab platform.
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Soil nitrogen conservation with continuous no-till management
Nutrient Cycling in Agroecosystems, 2008Co-Authors: John T. Spargo, Marcus M. Alley, Ronald F. Follett, James V. WallaceAbstract:Tillage management is an important regulator of organic matter decomposition and N mineralization in agroecosystems. Tillage has resulted in the loss of considerable organic N from surface soils. There is potential to rebuild and conserve substantial amounts of soil N where no-till management is implemented in crop production systems. The objectives of our research were to measure N conservation rate with continuous no-till management of grain cropping systems and evaluate its impact on mineralizable and inorganic soil N. Samples were collected from 63 sites in production fields using a rotation of corn (Zea mays L.)—wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.)—double-crop soybean (Glysine max L.) across three soil series [Bojac (Coarse-loamy, mixed, semiactive, thermic Typic Hapludults), Altavista (Fine-loamy, mixed semiactive, thermic Aquic Hapludults), and Kempsville (Fine-loamy, siliceous, subactive, thermic Typic Hapludults)] with a history of continuous no-till that ranged from 0 to 14 yrs. Thirty-two of the sites had a history of biosolids application. Soil cores were collected at each site from 0–2.5, 2.5–7.5 and 7.5–15 cm and analyzed for total N, Illinois soil N test-N (ISNT-N), and [NH4 + NO3]-N. A history of biosolids application increased the concentration of total soil N by 154 ± 66.8 mg N kg−1 (310 ± 140 kg N ha−1) but did not increase ISNT-N in the surface 0 – 15 cm. Continuous no-till increased the concentration of total soil N by 9.98 mg N kg−1 year−1 (22.2 ± 21.2 kg N ha−1 year−1) and ISNT-N by 1.68 mg N kg−1 year−1 in the surface 0–15 cm. The implementation of continuous no-till management in this cropping system has resulted in conservation of soil N.
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Soil carbon sequestration with continuous no-till management of grain cropping systems in the Virginia coastal plain
Soil & Tillage Research, 2008Co-Authors: John T. Spargo, Marcus M. Alley, Ronald F. Follett, James V. WallaceAbstract:Carbon sequestration in agroecosystems represents a significant opportunity to offset a portion of anthropogenic CO2 emissions. Climatic conditions in the Virginia coastal plain and modern production practices make it possible for high annual photosynthetic CO2 fixation. There is potential to sequester a substantial amount of C, and concomitantly improve soil quality, with the elimination of tillage for crop production in this region. The objectives of our research were to: (1) measure C sequestration rate with continuous no-till management of grain cropping systems of the Virginia middle coastal plain; (2) determine the influence of biosolids application history on C content and its interaction with tillage management; and (3) evaluate the impact of continuous no-till C stratification as an indicator of soil quality. Samples were collected from 63 sites in production fields using a rotation of corn (Zea mays L.)- wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.)/soybean double-crop (Glysine max L.) across three soil series (Bojac (coarse-loamy, mixed, semiactive, thermic Typic Hapludults), Altavista (fine- loamy, mixed semiactive, thermic Aquic Hapludults), and Kempsville (fine-loamy, siliceous, subactive, thermic Typic Hapludults)) with a history of continuous no-till management ranging from 0 to 14 years. Thirty-two of the sites had a history of biosolids application. Five soil cores were collected at each site from 0-2.5, 2.5-7.5 and 7.5-15 cm and analyzed for bulk density and soil C. Bulk density in the 0-2.5 cm layer decreased and C stratification ratio (0-2.5 cm:7.5-15 cm) increased with increasing duration of continuous no-till due to the accumulation of organic matter at the soil surface. A history of biosolids application resulted in an increase of 4.19 1.93 Mg C ha 1
Ronald F. Follett - One of the best experts on this subject based on the ideXlab platform.
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Soil nitrogen conservation with continuous no-till management
Nutrient Cycling in Agroecosystems, 2008Co-Authors: John T. Spargo, Marcus M. Alley, Ronald F. Follett, James V. WallaceAbstract:Tillage management is an important regulator of organic matter decomposition and N mineralization in agroecosystems. Tillage has resulted in the loss of considerable organic N from surface soils. There is potential to rebuild and conserve substantial amounts of soil N where no-till management is implemented in crop production systems. The objectives of our research were to measure N conservation rate with continuous no-till management of grain cropping systems and evaluate its impact on mineralizable and inorganic soil N. Samples were collected from 63 sites in production fields using a rotation of corn (Zea mays L.)—wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.)—double-crop soybean (Glysine max L.) across three soil series [Bojac (Coarse-loamy, mixed, semiactive, thermic Typic Hapludults), Altavista (Fine-loamy, mixed semiactive, thermic Aquic Hapludults), and Kempsville (Fine-loamy, siliceous, subactive, thermic Typic Hapludults)] with a history of continuous no-till that ranged from 0 to 14 yrs. Thirty-two of the sites had a history of biosolids application. Soil cores were collected at each site from 0–2.5, 2.5–7.5 and 7.5–15 cm and analyzed for total N, Illinois soil N test-N (ISNT-N), and [NH4 + NO3]-N. A history of biosolids application increased the concentration of total soil N by 154 ± 66.8 mg N kg−1 (310 ± 140 kg N ha−1) but did not increase ISNT-N in the surface 0 – 15 cm. Continuous no-till increased the concentration of total soil N by 9.98 mg N kg−1 year−1 (22.2 ± 21.2 kg N ha−1 year−1) and ISNT-N by 1.68 mg N kg−1 year−1 in the surface 0–15 cm. The implementation of continuous no-till management in this cropping system has resulted in conservation of soil N.
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Soil carbon sequestration with continuous no-till management of grain cropping systems in the Virginia coastal plain
Soil & Tillage Research, 2008Co-Authors: John T. Spargo, Marcus M. Alley, Ronald F. Follett, James V. WallaceAbstract:Carbon sequestration in agroecosystems represents a significant opportunity to offset a portion of anthropogenic CO2 emissions. Climatic conditions in the Virginia coastal plain and modern production practices make it possible for high annual photosynthetic CO2 fixation. There is potential to sequester a substantial amount of C, and concomitantly improve soil quality, with the elimination of tillage for crop production in this region. The objectives of our research were to: (1) measure C sequestration rate with continuous no-till management of grain cropping systems of the Virginia middle coastal plain; (2) determine the influence of biosolids application history on C content and its interaction with tillage management; and (3) evaluate the impact of continuous no-till C stratification as an indicator of soil quality. Samples were collected from 63 sites in production fields using a rotation of corn (Zea mays L.)- wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.)/soybean double-crop (Glysine max L.) across three soil series (Bojac (coarse-loamy, mixed, semiactive, thermic Typic Hapludults), Altavista (fine- loamy, mixed semiactive, thermic Aquic Hapludults), and Kempsville (fine-loamy, siliceous, subactive, thermic Typic Hapludults)) with a history of continuous no-till management ranging from 0 to 14 years. Thirty-two of the sites had a history of biosolids application. Five soil cores were collected at each site from 0-2.5, 2.5-7.5 and 7.5-15 cm and analyzed for bulk density and soil C. Bulk density in the 0-2.5 cm layer decreased and C stratification ratio (0-2.5 cm:7.5-15 cm) increased with increasing duration of continuous no-till due to the accumulation of organic matter at the soil surface. A history of biosolids application resulted in an increase of 4.19 1.93 Mg C ha 1
