Spectroscopic Investigation on the Effects of Biochar and Soluble Phosphorus on Grass Clipping Vermicomposting

Seeking to evaluate the hypothesis that biochar optimises the composting and vermicomposting processes as well as their product quality, we carried out field and greenhouse experiments. Four grass clipping composting treatments (only grass, grass + single superphosphate (SSP), grass + biochar and gr...

Full description

Bibliographic Details
Main Authors: Etelvino Henrique Novotny, Fabiano de Carvalho Balieiro, Ruben Auccaise, Vinícius de Melo Benites, Heitor Luiz da Costa Coutinho
Format: Article
Language:English
Published: MDPI AG 2022-07-01
Series:Agriculture
Subjects:
Online Access:https://www.mdpi.com/2077-0472/12/7/1011
_version_ 1797441494586490880
author Etelvino Henrique Novotny
Fabiano de Carvalho Balieiro
Ruben Auccaise
Vinícius de Melo Benites
Heitor Luiz da Costa Coutinho
author_facet Etelvino Henrique Novotny
Fabiano de Carvalho Balieiro
Ruben Auccaise
Vinícius de Melo Benites
Heitor Luiz da Costa Coutinho
author_sort Etelvino Henrique Novotny
collection DOAJ
description Seeking to evaluate the hypothesis that biochar optimises the composting and vermicomposting processes as well as their product quality, we carried out field and greenhouse experiments. Four grass clipping composting treatments (only grass, grass + single superphosphate (SSP), grass + biochar and grass + SSP + biochar) were evaluated. At the end of the maturation period (150 days), the composts were submitted to vermicomposting (Eisenia fetida earthworm) for an additional 90 days. Ordinary fine charcoal was selected due to its low cost (a by-product of charcoal production) and great availability; this is important since the obtained product presents low commercial value. A greater maturity of the organic matter (humification) was observed in the vermicompost treatments compared with the compost-only treatments. The addition of phosphate significantly reduced the pH (from 6.7 to 4.8), doubled the electrical conductivity and inhibited biological activity, resulting in less than 2% of the number of earthworms found in the treatment without phosphate. The addition of soluble phosphate inhibited the humification process, resulting in a less-stable compound with the preservation of labile structures, primarily cellulose. The P species found corroborate these findings because the pyrophosphate conversion from SSP in the absence of biochar may explain the strong acidification and increased electric conductivity. Biochar appears to prevent this conversion, thus mitigating the deleterious effects of SSP and favouring the formation of organic P species from SSP (78.5% of P in organic form with biochar compared to only 12.8% in the treatments without biochar). In short, biochar decreases pyrophosphate formation from SSP, avoiding acidification and salinity; therefore, biochar improves the whole composting and vermicomposting process and product quality. Vermicompost with SSP and biochar should be tested as a soil conditioner on account of its greater proportion of stabilized C and organic P.
first_indexed 2024-03-09T12:23:54Z
format Article
id doaj.art-973735fedc624c8c99c8f3d76b532f3c
institution Directory Open Access Journal
issn 2077-0472
language English
last_indexed 2024-03-09T12:23:54Z
publishDate 2022-07-01
publisher MDPI AG
record_format Article
series Agriculture
spelling doaj.art-973735fedc624c8c99c8f3d76b532f3c2023-11-30T22:37:26ZengMDPI AGAgriculture2077-04722022-07-01127101110.3390/agriculture12071011Spectroscopic Investigation on the Effects of Biochar and Soluble Phosphorus on Grass Clipping VermicompostingEtelvino Henrique Novotny0Fabiano de Carvalho Balieiro1Ruben Auccaise2Vinícius de Melo Benites3Heitor Luiz da Costa Coutinho4Embrapa Solos, Rua Jardim Botânico, 1024, Rio de Janeiro 22460-000, BrazilEmbrapa Solos, Rua Jardim Botânico, 1024, Rio de Janeiro 22460-000, BrazilDepartamento de Física, Universidade Estadual de Ponta Grossa, Av. General Carlos Cavalcanti 4748, Ponta Grossa 84030-900, BrazilEmbrapa Solos, Rua Jardim Botânico, 1024, Rio de Janeiro 22460-000, BrazilEmbrapa Solos, Rua Jardim Botânico, 1024, Rio de Janeiro 22460-000, BrazilSeeking to evaluate the hypothesis that biochar optimises the composting and vermicomposting processes as well as their product quality, we carried out field and greenhouse experiments. Four grass clipping composting treatments (only grass, grass + single superphosphate (SSP), grass + biochar and grass + SSP + biochar) were evaluated. At the end of the maturation period (150 days), the composts were submitted to vermicomposting (Eisenia fetida earthworm) for an additional 90 days. Ordinary fine charcoal was selected due to its low cost (a by-product of charcoal production) and great availability; this is important since the obtained product presents low commercial value. A greater maturity of the organic matter (humification) was observed in the vermicompost treatments compared with the compost-only treatments. The addition of phosphate significantly reduced the pH (from 6.7 to 4.8), doubled the electrical conductivity and inhibited biological activity, resulting in less than 2% of the number of earthworms found in the treatment without phosphate. The addition of soluble phosphate inhibited the humification process, resulting in a less-stable compound with the preservation of labile structures, primarily cellulose. The P species found corroborate these findings because the pyrophosphate conversion from SSP in the absence of biochar may explain the strong acidification and increased electric conductivity. Biochar appears to prevent this conversion, thus mitigating the deleterious effects of SSP and favouring the formation of organic P species from SSP (78.5% of P in organic form with biochar compared to only 12.8% in the treatments without biochar). In short, biochar decreases pyrophosphate formation from SSP, avoiding acidification and salinity; therefore, biochar improves the whole composting and vermicomposting process and product quality. Vermicompost with SSP and biochar should be tested as a soil conditioner on account of its greater proportion of stabilized C and organic P.https://www.mdpi.com/2077-0472/12/7/1011<sup>13</sup>C nuclear magnetic resonance<sup>31</sup>P nuclear magnetic resonancecharcoal<i>Eisenia fetida</i>pyrogenic carbon
spellingShingle Etelvino Henrique Novotny
Fabiano de Carvalho Balieiro
Ruben Auccaise
Vinícius de Melo Benites
Heitor Luiz da Costa Coutinho
Spectroscopic Investigation on the Effects of Biochar and Soluble Phosphorus on Grass Clipping Vermicomposting
Agriculture
<sup>13</sup>C nuclear magnetic resonance
<sup>31</sup>P nuclear magnetic resonance
charcoal
<i>Eisenia fetida</i>
pyrogenic carbon
title Spectroscopic Investigation on the Effects of Biochar and Soluble Phosphorus on Grass Clipping Vermicomposting
title_full Spectroscopic Investigation on the Effects of Biochar and Soluble Phosphorus on Grass Clipping Vermicomposting
title_fullStr Spectroscopic Investigation on the Effects of Biochar and Soluble Phosphorus on Grass Clipping Vermicomposting
title_full_unstemmed Spectroscopic Investigation on the Effects of Biochar and Soluble Phosphorus on Grass Clipping Vermicomposting
title_short Spectroscopic Investigation on the Effects of Biochar and Soluble Phosphorus on Grass Clipping Vermicomposting
title_sort spectroscopic investigation on the effects of biochar and soluble phosphorus on grass clipping vermicomposting
topic <sup>13</sup>C nuclear magnetic resonance
<sup>31</sup>P nuclear magnetic resonance
charcoal
<i>Eisenia fetida</i>
pyrogenic carbon
url https://www.mdpi.com/2077-0472/12/7/1011
work_keys_str_mv AT etelvinohenriquenovotny spectroscopicinvestigationontheeffectsofbiocharandsolublephosphorusongrassclippingvermicomposting
AT fabianodecarvalhobalieiro spectroscopicinvestigationontheeffectsofbiocharandsolublephosphorusongrassclippingvermicomposting
AT rubenauccaise spectroscopicinvestigationontheeffectsofbiocharandsolublephosphorusongrassclippingvermicomposting
AT viniciusdemelobenites spectroscopicinvestigationontheeffectsofbiocharandsolublephosphorusongrassclippingvermicomposting
AT heitorluizdacostacoutinho spectroscopicinvestigationontheeffectsofbiocharandsolublephosphorusongrassclippingvermicomposting