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A comparison of corn (Zea mays L.) residue and its biochar on soil C and plant growth.

Calderón FJ, Benjamin J, Vigil MF - PLoS ONE (2015)

Bottom Line: The 500°C biochar had little to no effect on plant biomass.With incubation we measured lower soil NO3 content in the corn stalk treatment than in the biochar-amended soils, suggesting that the millet growth reduction in the stalk treatment was mainly driven by N limitation, whereas other factors contributed to the biomass yield reductions in the biochar treatments.Absorbances near 1600, 1500-1420, and 1345 cm-1 represented the more refractory SOM moieties.

View Article: PubMed Central - PubMed

Affiliation: USDA-ARS, 40335 Co Rd GG., Central Great Plains Research Station, Akron, Colorado, United States of America.

ABSTRACT
In order to properly determine the value of charring crop residues, the C use efficiency and effects on crop performance of biochar needs to be compared to the un-charred crop residues. In this study we compared the addition of corn stalks to soil, with equivalent additions of charred (300 °C and 500 °C) corn residues. Two experiments were conducted: a long term laboratory mineralization, and a growth chamber trial with proso millet plants. In the laboratory, we measured soil mineral N dynamics, C use efficiency, and soil organic matter (SOM) chemical changes via infrared spectroscopy. The 300 °C biochar decreased plant biomass relative to a nothing added control. The 500°C biochar had little to no effect on plant biomass. With incubation we measured lower soil NO3 content in the corn stalk treatment than in the biochar-amended soils, suggesting that the millet growth reduction in the stalk treatment was mainly driven by N limitation, whereas other factors contributed to the biomass yield reductions in the biochar treatments. Corn stalks had a C sequestration use efficiency of up to 0.26, but charring enhanced C sequestration to values that ranged from 0.64 to 1.0. Infrared spectroscopy of the soils as they mineralized showed that absorbance at 3400, 2925-2850, 1737 cm-1, and 1656 cm-1 decreased during the incubation and can be regarded as labile SOM, corn residue, or biochar bands. Absorbances near 1600, 1500-1420, and 1345 cm-1 represented the more refractory SOM moieties. Our results show that adding crop residue biochar to soil is a sound C sequestration technology compared to letting the crop residues decompose in the field. This is because the resistance to decomposition of the chars after soil amendment offsets any C losses during charring of the crop residues.

No MeSH data available.


Related in: MedlinePlus

Spectral subtraction of the mid infrared spectra from the unamended soil controls, soil plus stalk feedstock, soil plus 300 degree biochar, and soil plus 500 degree biochar treatments.Subtractions are time zero spectra minus 48 wk incubation soil spectra. Top graph is the High-erosion Soil, and bottom graph is the Low-erosion Soil. wn = wavenumbers in cm-1.
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pone.0121006.g004: Spectral subtraction of the mid infrared spectra from the unamended soil controls, soil plus stalk feedstock, soil plus 300 degree biochar, and soil plus 500 degree biochar treatments.Subtractions are time zero spectra minus 48 wk incubation soil spectra. Top graph is the High-erosion Soil, and bottom graph is the Low-erosion Soil. wn = wavenumbers in cm-1.

Mentions: We carried out spectral subtractions of the time zero minus 40 week incubated soils to determine how SOM chemistry changes as it mineralizes in the presence or absence of biochar or corn feedstock (Fig 4). Both high-erosion and low-erosion soils lost absorbance at the broad band around 3400 cm-1 for OH/NH stretching and the aliphatic CH bands between 2925–2850 cm-1 [6]. The absorbance loss at 2925–2850 cm-1 was more marked with the stalk treatment. The subtracted spectrum for the stalks forms a shoulder at 1737 cm-1 for carbonyl C = O (Fig 4). All soils had a marked reduction in absorbance at 1656 cm-1, a band attributed to amide C = O stretch, but also close to the aromatic C = C band between 1650–1600 [6]. The decreased absorbance at 1390 cm-1 is due to loss of carboxylate or phenolic C-O functional groups. Reductions in the 1249 cm-1 band, which are marked in the Stalk treatment, correspond to a combination of carboxylic acid C-O stretch, OH deformation, and ester, or phenol C-O stretch. Absorbance at 1040 cm-1 increased during the incubation in several treatments. This band is within the polysaccharide C-O stretch region, but could also be due to Si-O stretch (Fig 4).


A comparison of corn (Zea mays L.) residue and its biochar on soil C and plant growth.

Calderón FJ, Benjamin J, Vigil MF - PLoS ONE (2015)

Spectral subtraction of the mid infrared spectra from the unamended soil controls, soil plus stalk feedstock, soil plus 300 degree biochar, and soil plus 500 degree biochar treatments.Subtractions are time zero spectra minus 48 wk incubation soil spectra. Top graph is the High-erosion Soil, and bottom graph is the Low-erosion Soil. wn = wavenumbers in cm-1.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4383588&req=5

pone.0121006.g004: Spectral subtraction of the mid infrared spectra from the unamended soil controls, soil plus stalk feedstock, soil plus 300 degree biochar, and soil plus 500 degree biochar treatments.Subtractions are time zero spectra minus 48 wk incubation soil spectra. Top graph is the High-erosion Soil, and bottom graph is the Low-erosion Soil. wn = wavenumbers in cm-1.
Mentions: We carried out spectral subtractions of the time zero minus 40 week incubated soils to determine how SOM chemistry changes as it mineralizes in the presence or absence of biochar or corn feedstock (Fig 4). Both high-erosion and low-erosion soils lost absorbance at the broad band around 3400 cm-1 for OH/NH stretching and the aliphatic CH bands between 2925–2850 cm-1 [6]. The absorbance loss at 2925–2850 cm-1 was more marked with the stalk treatment. The subtracted spectrum for the stalks forms a shoulder at 1737 cm-1 for carbonyl C = O (Fig 4). All soils had a marked reduction in absorbance at 1656 cm-1, a band attributed to amide C = O stretch, but also close to the aromatic C = C band between 1650–1600 [6]. The decreased absorbance at 1390 cm-1 is due to loss of carboxylate or phenolic C-O functional groups. Reductions in the 1249 cm-1 band, which are marked in the Stalk treatment, correspond to a combination of carboxylic acid C-O stretch, OH deformation, and ester, or phenol C-O stretch. Absorbance at 1040 cm-1 increased during the incubation in several treatments. This band is within the polysaccharide C-O stretch region, but could also be due to Si-O stretch (Fig 4).

Bottom Line: The 500°C biochar had little to no effect on plant biomass.With incubation we measured lower soil NO3 content in the corn stalk treatment than in the biochar-amended soils, suggesting that the millet growth reduction in the stalk treatment was mainly driven by N limitation, whereas other factors contributed to the biomass yield reductions in the biochar treatments.Absorbances near 1600, 1500-1420, and 1345 cm-1 represented the more refractory SOM moieties.

View Article: PubMed Central - PubMed

Affiliation: USDA-ARS, 40335 Co Rd GG., Central Great Plains Research Station, Akron, Colorado, United States of America.

ABSTRACT
In order to properly determine the value of charring crop residues, the C use efficiency and effects on crop performance of biochar needs to be compared to the un-charred crop residues. In this study we compared the addition of corn stalks to soil, with equivalent additions of charred (300 °C and 500 °C) corn residues. Two experiments were conducted: a long term laboratory mineralization, and a growth chamber trial with proso millet plants. In the laboratory, we measured soil mineral N dynamics, C use efficiency, and soil organic matter (SOM) chemical changes via infrared spectroscopy. The 300 °C biochar decreased plant biomass relative to a nothing added control. The 500°C biochar had little to no effect on plant biomass. With incubation we measured lower soil NO3 content in the corn stalk treatment than in the biochar-amended soils, suggesting that the millet growth reduction in the stalk treatment was mainly driven by N limitation, whereas other factors contributed to the biomass yield reductions in the biochar treatments. Corn stalks had a C sequestration use efficiency of up to 0.26, but charring enhanced C sequestration to values that ranged from 0.64 to 1.0. Infrared spectroscopy of the soils as they mineralized showed that absorbance at 3400, 2925-2850, 1737 cm-1, and 1656 cm-1 decreased during the incubation and can be regarded as labile SOM, corn residue, or biochar bands. Absorbances near 1600, 1500-1420, and 1345 cm-1 represented the more refractory SOM moieties. Our results show that adding crop residue biochar to soil is a sound C sequestration technology compared to letting the crop residues decompose in the field. This is because the resistance to decomposition of the chars after soil amendment offsets any C losses during charring of the crop residues.

No MeSH data available.


Related in: MedlinePlus