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| Ducey, Tom; Ippolito, J.A.; Cantrell, K.B.; Novak, J.M.; Lentz, R.D.. |
| It has been demonstrated that soil amended with biochar, designed specifically for use as a soil conditioner, results in changes to the microbial populations that reside therein. These changes have been reflected in studies measuring variations in microbial activity, biomass, and community structure. Despite these studies, very few experiments have been performed examining microbial genes involved in nutrient cycling processes. Given the paucity of research in this area, we designed a six-month study in a Portneuf soil (coarse-silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid) treated with three levels (1%, 2%, and 10% w/w ratio) of a biochar pyrolyzed from switchgrass (Panicum virgatum) at 350°C and steam activated at 800°C to measure the... |
| Tipo: Article |
Palavras-chave: Amendments; Chemistry; Nitrogen; Soil. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1517/1/1481.pdf |
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| Ippolito, J.A.; Spokas, K.A.; Novak, J.M.; Lentz, R.D.; Cantrell, K.B.. |
| Biochar is the carbonaceous solid byproduct of the thermochemical conversion of a carbon-bearing organic material, commonly high in cellulose, hemicelluloses, or lignin content, for the purposes of carbon sequestration and storage. More specifically, the thermal conversion process known as pyrolysis occurs when carbon-containing substances are introduced to elevated temperatures in the absence of oxygen at varying residence times, yielding biochar. Several pyrolysis techniques employed to produce biochar differ in the temperature of reaction and residence time in the reactor. Different reactor residence times are described as slow (hours to days), fast (seconds to minutes), and flash (seconds). Fast or flash pyrolysis typically occurs around 500oC with... |
| Tipo: Book Section |
Palavras-chave: Fertility; Soil quality; Fertilizer. |
| Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1590/1/1547.pdf |
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| Novak, J.M.; Busscher, W.J.; Watts, D.W.; Amonette, J.; Ippolito, J.A.; Lima, I.M.; Gaskin, J.; Das, K.C.; Steiner, C.; Ahmedna, M.; Rehrah, D.; Schomberg, H.H.. |
| Droughts associated with low or erratic rainfall distribution can cause detrimental crop moisture stress. This problem is exacerbated in the USA’s arid western and southeastern Coastal Plain due to poor rainfall distribution, poor soil water storage, or poorly-aggregated, subsurface hard layers that limit root penetration. We hypothesized that soil physical deficiencies may be improved by biochar applications. Research indicates a single biochar will not serve as a universal supplement to all soils; consequently, biochars may need to be designed with physico-chemical properties that can ameliorate specific soil physical deficiencies. We conducted a laboratory study that examined the effect of biochar on soil moisture retention and aggregate formation.... |
| Tipo: Article |
Palavras-chave: Soil quality; Soil water (soil moisture). |
| Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1523/1/1485.pdf |
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| Ippolito, J.A.; Ducey, Tom; Cantrell, K.B.; Novak, J.M.; Lentz, R.D.. |
| An acidic (pH 5.8) biochar was created using a low pyrolysis temperature (350 degrees celsius) and steam activation to potentially improve the soil physicochemical status of an eroded calcareous soil. Biochar was added at 0, 1, 2, and 10 percent (by weight) to an eroded Portneuf soil (coarse-silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid) and destructively sampled at 1, 2, 3, 4, 5, and 6 month intervals. Soil was analyzed for volumetric water content, pH, nitrate-nitrogen, ammonium-nitrogen, plant-available iron, zinc, manganese, copper, and phosphorus, organic carbon, carbon dioxide respiration, and microbial enumeration via extractable DNA and 16S rRNA gene copies. Soil water content increased with biochar application regardless of rate;... |
| Tipo: Article |
Palavras-chave: Calcareous soil; Chemistry; Soil. |
| Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1598/1/1556.pdf |
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| Spokas, K.A.; Novak, J.M.; Masiello, C.A.; Johnson, M.G.; Colosky, E.C.; Ippolito\, J.A.. |
| Data collected from both artificially and field (naturally) weathered biochar suggest that a potentially significant pathway of biochar disappearance is through physical breakdown of the biochar structure. Through scanning electron microscopy (SEM) we characterized this physical weathering which increased structural fractures and possessed higher numbers of liberated biochar fragments. This was hypothesized to be due to the graphitic sheet expansion accompanying water sorption coupled with comminution. These fragments can be on the micro and nano-scale, but are still carbon-rich particles with no detectable alteration in the oxygen to carbon ratio of the original biochar. However, these particles are now easily dissolved and could be moved by infiltration.... |
| Tipo: Article |
Palavras-chave: Soil. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1547/1/1502.pdf |
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| Spokas, K.A.; Novak, J.M.; Masiello, C.A.; Johnson, M.G.; Colosky, E.C.; Ippolito, J.A.; Trigo, C.. |
| Data collected from both artificially and field (naturally) weathered biochar suggest that a potentially significant pathway of biochar disappearance is through physical breakdown of the biochar structure. Through scanning electron microscopy (SEM) we characterized this physical weathering which increased structural fractures and possessed higher numbers of liberated biochar fragments. This was hypothesized to be due to the graphitic sheet expansion accompanying water sorption coupled with comminution. These fragments can be on the micro and nano-scale, but are still carbon-rich particles with no detectable alteration in the oxygen to carbon ratio of the original biochar. However, these particles are now easily dissolved and could be moved by... |
| Tipo: Article |
Palavras-chave: Dissolved Organic Carbon (DOC). |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1548/1/1502.pdf |
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| Novak, J.M.; Ippolito, J.A.; Lentz, R.D.; Spokas, K.A.; Bolster, C.H.; Sistani, K.R.; Trippe, K.M.; Phillips, C.L.; Johnson, M.G.. |
| Biochar is being evaluated by scientists from the United States Department of Agriculture (USDA) Agricultural Research Service (ARS) for its potential to sequester soil C, to improve soil health, and to increase crop yields. ARS scientists from multiple locations such as Florence, SC, Kimberly, ID, Bowling Green, KY, Corvallis, OR, and St. Paul, MN, are conducting investigations with agronomic experiments at the laboratory, greenhouse, and field plot scales. To further expand biochars utility, ARS scientists have collaborated with United States Environmental Protection Agency (US EPA) investigators to reclaim mine-impacted soils. In the agronomic investigations, both positive and negative aspects of biochar application were revealed. In some experiments,... |
| Tipo: Article |
Palavras-chave: Fertility; Soil quality; Soil. |
| Ano: 2016 |
URL: http://eprints.nwisrl.ars.usda.gov/1621/1/1578.pdf |
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