Cargando…

Nitrogen turnover and N(2)O/N(2) ratio of three contrasting tropical soils amended with biochar

Biochar has been reported to reduce emission of nitrous oxide (N(2)O) from soils, but the mechanisms responsible remain fragmentary. For example, it is unclear how biochar effects on N(2)O emissions are mediated through biochar effects on soil gross N turnover rates. Hence, we conducted an incubatio...

Descripción completa

Detalles Bibliográficos
Autores principales: Fungo, Bernard, Chen, Zhe, Butterbach-Bahl, Klaus, Lehmannn, Johannes, Saiz, Gustavo, Braojos, Víctor, Kolar, Allison, Rittl, Tatjana F., Tenywa, Moses, Kalbitz, Karsten, Neufeldt, Henry, Dannenmann, Michael
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Elsevier Scientific Pub. Co 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6559130/
https://www.ncbi.nlm.nih.gov/pubmed/31423022
http://dx.doi.org/10.1016/j.geoderma.2019.04.007
_version_ 1783425775378104320
author Fungo, Bernard
Chen, Zhe
Butterbach-Bahl, Klaus
Lehmannn, Johannes
Saiz, Gustavo
Braojos, Víctor
Kolar, Allison
Rittl, Tatjana F.
Tenywa, Moses
Kalbitz, Karsten
Neufeldt, Henry
Dannenmann, Michael
author_facet Fungo, Bernard
Chen, Zhe
Butterbach-Bahl, Klaus
Lehmannn, Johannes
Saiz, Gustavo
Braojos, Víctor
Kolar, Allison
Rittl, Tatjana F.
Tenywa, Moses
Kalbitz, Karsten
Neufeldt, Henry
Dannenmann, Michael
author_sort Fungo, Bernard
collection PubMed
description Biochar has been reported to reduce emission of nitrous oxide (N(2)O) from soils, but the mechanisms responsible remain fragmentary. For example, it is unclear how biochar effects on N(2)O emissions are mediated through biochar effects on soil gross N turnover rates. Hence, we conducted an incubation study with three contrasting agricultural soils from Kenya (an Acrisol cultivated for 10-years (Acrisol10); an Acrisol cultivated for over 100-years (Acrisol100); a Ferralsol cultivated for over 100 years (Ferralsol)). The soils were amended with biochar at either 2% or 4% w/w. The (15)N pool dilution technique was used to quantify gross N mineralization and nitrification and microbial consumption of extractable N over a 20-day incubation period at 25 °C and 70% water holding capacity of the soil, accompanied by N(2)O emissions measurements. Direct measurements of N(2) emissions were conducted using the helium gas flow soil core method. N(2)O emissions varied across soils with higher emissions in Acrisols than in Ferralsols. Addition of 2% biochar reduced N(2)O emissions in all soils by 53 to 78% with no significant further reduction induced by addition at 4%. Biochar effects on soil nitrate concentrations were highly variable across soils, ranging from a reduction, no effect and an increase. Biochar addition stimulated gross N mineralization in Acrisol-10 and Acrisol-100 soils at both addition rates with no effect observed for the Ferralsol. In contrast, gross nitrification was stimulated in only one soil but only at a 4% application rate. Also, biochar effects on increased NH(4)(+) immobilization and NO(3)(−)consumption strongly varied across the three investigated soils. The variable and bidirectional biochar effects on gross N turnover in conjunction with the unambiguous and consistent reduction of N(2)O emissions suggested that the inhibiting effect of biochar on soil N(2)O emission seemed to be decoupled from gross microbial N turnover processes. With biochar application, N(2) emissions were about an order of magnitude higher for Acrisol-10 soils compared to Acrisol-100 and Ferralsol-100 soils. Our N(2)O and N(2) flux data thus support an explanation of direct promotion of gross N(2)O reduction by biochar rather than effects on soil extractable N dynamics. Effects of biochar on soil extractable N and gross N turnover, however, might be highly variable across different soils as found here for three typical agricultural soils of Kenya.
format Online
Article
Text
id pubmed-6559130
institution National Center for Biotechnology Information
language English
publishDate 2019
publisher Elsevier Scientific Pub. Co
record_format MEDLINE/PubMed
spelling pubmed-65591302019-08-15 Nitrogen turnover and N(2)O/N(2) ratio of three contrasting tropical soils amended with biochar Fungo, Bernard Chen, Zhe Butterbach-Bahl, Klaus Lehmannn, Johannes Saiz, Gustavo Braojos, Víctor Kolar, Allison Rittl, Tatjana F. Tenywa, Moses Kalbitz, Karsten Neufeldt, Henry Dannenmann, Michael Geoderma Article Biochar has been reported to reduce emission of nitrous oxide (N(2)O) from soils, but the mechanisms responsible remain fragmentary. For example, it is unclear how biochar effects on N(2)O emissions are mediated through biochar effects on soil gross N turnover rates. Hence, we conducted an incubation study with three contrasting agricultural soils from Kenya (an Acrisol cultivated for 10-years (Acrisol10); an Acrisol cultivated for over 100-years (Acrisol100); a Ferralsol cultivated for over 100 years (Ferralsol)). The soils were amended with biochar at either 2% or 4% w/w. The (15)N pool dilution technique was used to quantify gross N mineralization and nitrification and microbial consumption of extractable N over a 20-day incubation period at 25 °C and 70% water holding capacity of the soil, accompanied by N(2)O emissions measurements. Direct measurements of N(2) emissions were conducted using the helium gas flow soil core method. N(2)O emissions varied across soils with higher emissions in Acrisols than in Ferralsols. Addition of 2% biochar reduced N(2)O emissions in all soils by 53 to 78% with no significant further reduction induced by addition at 4%. Biochar effects on soil nitrate concentrations were highly variable across soils, ranging from a reduction, no effect and an increase. Biochar addition stimulated gross N mineralization in Acrisol-10 and Acrisol-100 soils at both addition rates with no effect observed for the Ferralsol. In contrast, gross nitrification was stimulated in only one soil but only at a 4% application rate. Also, biochar effects on increased NH(4)(+) immobilization and NO(3)(−)consumption strongly varied across the three investigated soils. The variable and bidirectional biochar effects on gross N turnover in conjunction with the unambiguous and consistent reduction of N(2)O emissions suggested that the inhibiting effect of biochar on soil N(2)O emission seemed to be decoupled from gross microbial N turnover processes. With biochar application, N(2) emissions were about an order of magnitude higher for Acrisol-10 soils compared to Acrisol-100 and Ferralsol-100 soils. Our N(2)O and N(2) flux data thus support an explanation of direct promotion of gross N(2)O reduction by biochar rather than effects on soil extractable N dynamics. Effects of biochar on soil extractable N and gross N turnover, however, might be highly variable across different soils as found here for three typical agricultural soils of Kenya. Elsevier Scientific Pub. Co 2019-08-15 /pmc/articles/PMC6559130/ /pubmed/31423022 http://dx.doi.org/10.1016/j.geoderma.2019.04.007 Text en © 2019 The Authors http://creativecommons.org/licenses/by/4.0/ This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Fungo, Bernard
Chen, Zhe
Butterbach-Bahl, Klaus
Lehmannn, Johannes
Saiz, Gustavo
Braojos, Víctor
Kolar, Allison
Rittl, Tatjana F.
Tenywa, Moses
Kalbitz, Karsten
Neufeldt, Henry
Dannenmann, Michael
Nitrogen turnover and N(2)O/N(2) ratio of three contrasting tropical soils amended with biochar
title Nitrogen turnover and N(2)O/N(2) ratio of three contrasting tropical soils amended with biochar
title_full Nitrogen turnover and N(2)O/N(2) ratio of three contrasting tropical soils amended with biochar
title_fullStr Nitrogen turnover and N(2)O/N(2) ratio of three contrasting tropical soils amended with biochar
title_full_unstemmed Nitrogen turnover and N(2)O/N(2) ratio of three contrasting tropical soils amended with biochar
title_short Nitrogen turnover and N(2)O/N(2) ratio of three contrasting tropical soils amended with biochar
title_sort nitrogen turnover and n(2)o/n(2) ratio of three contrasting tropical soils amended with biochar
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6559130/
https://www.ncbi.nlm.nih.gov/pubmed/31423022
http://dx.doi.org/10.1016/j.geoderma.2019.04.007
work_keys_str_mv AT fungobernard nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT chenzhe nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT butterbachbahlklaus nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT lehmannnjohannes nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT saizgustavo nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT braojosvictor nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT kolarallison nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT rittltatjanaf nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT tenywamoses nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT kalbitzkarsten nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT neufeldthenry nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar
AT dannenmannmichael nitrogenturnoverandn2on2ratioofthreecontrastingtropicalsoilsamendedwithbiochar