The mineralization of sulfur from organic residues measured by inverse isotope dilution
Sulfur (S) deficiency in soils is increasingly recognized in agricultural systems. The quantification of S mineralization/immobilization processes after incorporation of organic materials into soils is a key factor to predict the availability of S to growing plants. However, immobilization and miner...
| Main Authors: | , , |
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| Format: | Journal Article |
| Language: | Inglés |
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Elsevier
2006
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10568/99924 |
| _version_ | 1855521939864420352 |
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| author | Nziguheba, G. Smolders, E. Merckx, Roel |
| author_browse | Merckx, Roel Nziguheba, G. Smolders, E. |
| author_facet | Nziguheba, G. Smolders, E. Merckx, Roel |
| author_sort | Nziguheba, G. |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | Sulfur (S) deficiency in soils is increasingly recognized in agricultural systems. The quantification of S mineralization/immobilization processes after incorporation of organic materials into soils is a key factor to predict the availability of S to growing plants. However, immobilization and mineralization occur simultaneously making the quantification of the magnitude of each process difficult. We used the inverse isotope (35SO4) dilution technique to quantify immobilization and mineralization fluxes after incorporation of two organic residues with contrasting C/S ratio's (cabbage or wheat straw) into a sandy soil in planted and unplanted soils (pot trial with ryegrass and incubation). The soil was labeled with 35SO4 and incubated for 63 days prior to the application of residues. The specific activity (SA) of soil-extractable SO4 did not change significantly in the control soil during the subsequent experimental period despite significant net mineralization, illustrating that labile-S in soil was homogenously labeled. Application of residues decreased the SAs during the incubation due to the dilution with unlabeled-S from the residues. A three-compartment dynamic model was fitted to the SA data predicting that gross mineralization of residue-S was almost complete over 43 days incubation although this release was not matched by the increase in soil SO4 due to immobilization reactions. Soil-extractable SO4 was significantly increased in the cabbage-treated soil while the reverse was true in the wheat straw amended soil in which the S-immobilization was almost twice the gross mineralization of residue-S. The SA of S in ryegrass were maximally 15% lower than in corresponding soil extracts suggesting that residue mineralization was similar in planted and unplanted soils. The inverse isotope dilution method offers potential for screening S release of different residues; however the details of the dynamics of soil-S isotopes show that the individual fluxes are not constant during the incubation. |
| format | Journal Article |
| id | CGSpace99924 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 2006 |
| publishDateRange | 2006 |
| publishDateSort | 2006 |
| publisher | Elsevier |
| publisherStr | Elsevier |
| record_format | dspace |
| spelling | CGSpace999242024-08-27T10:35:34Z The mineralization of sulfur from organic residues measured by inverse isotope dilution Nziguheba, G. Smolders, E. Merckx, Roel soil wheat straw cabbages Sulfur (S) deficiency in soils is increasingly recognized in agricultural systems. The quantification of S mineralization/immobilization processes after incorporation of organic materials into soils is a key factor to predict the availability of S to growing plants. However, immobilization and mineralization occur simultaneously making the quantification of the magnitude of each process difficult. We used the inverse isotope (35SO4) dilution technique to quantify immobilization and mineralization fluxes after incorporation of two organic residues with contrasting C/S ratio's (cabbage or wheat straw) into a sandy soil in planted and unplanted soils (pot trial with ryegrass and incubation). The soil was labeled with 35SO4 and incubated for 63 days prior to the application of residues. The specific activity (SA) of soil-extractable SO4 did not change significantly in the control soil during the subsequent experimental period despite significant net mineralization, illustrating that labile-S in soil was homogenously labeled. Application of residues decreased the SAs during the incubation due to the dilution with unlabeled-S from the residues. A three-compartment dynamic model was fitted to the SA data predicting that gross mineralization of residue-S was almost complete over 43 days incubation although this release was not matched by the increase in soil SO4 due to immobilization reactions. Soil-extractable SO4 was significantly increased in the cabbage-treated soil while the reverse was true in the wheat straw amended soil in which the S-immobilization was almost twice the gross mineralization of residue-S. The SA of S in ryegrass were maximally 15% lower than in corresponding soil extracts suggesting that residue mineralization was similar in planted and unplanted soils. The inverse isotope dilution method offers potential for screening S release of different residues; however the details of the dynamics of soil-S isotopes show that the individual fluxes are not constant during the incubation. 2006-08 2019-03-03T05:54:06Z 2019-03-03T05:54:06Z Journal Article https://hdl.handle.net/10568/99924 en Limited Access Elsevier Nziguheba, G., Smolders, E. & Merckx, R. (2006). The mineralization of sulfur from organic residues measured by inverse isotope dilution. Soil Biology and Biochemistry, 38(8), 2278-2284. |
| spellingShingle | soil wheat straw cabbages Nziguheba, G. Smolders, E. Merckx, Roel The mineralization of sulfur from organic residues measured by inverse isotope dilution |
| title | The mineralization of sulfur from organic residues measured by inverse isotope dilution |
| title_full | The mineralization of sulfur from organic residues measured by inverse isotope dilution |
| title_fullStr | The mineralization of sulfur from organic residues measured by inverse isotope dilution |
| title_full_unstemmed | The mineralization of sulfur from organic residues measured by inverse isotope dilution |
| title_short | The mineralization of sulfur from organic residues measured by inverse isotope dilution |
| title_sort | mineralization of sulfur from organic residues measured by inverse isotope dilution |
| topic | soil wheat straw cabbages |
| url | https://hdl.handle.net/10568/99924 |
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