Details zur Publikation |
| Kategorie | Textpublikation |
| Referenztyp | Zeitschriften |
| DOI | 10.1016/j.geoderma.2023.116472 |
| Lizenz |
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| Titel (primär) | Soil organic carbon sequestration in agricultural long-term field experiments as derived from particulate and mineral-associated organic matter |
| Autor | Just, C.; Armbruster, M.; Barkusky, D.; Baumecker, M.; Diepolder, M.; Döring, T.F.; Heigl, L.; Honermeier, B.; Jate, M.; Merbach, I.; Rusch, C.; Schubert, D.; Schulz, F.; Schweitzer, K.; Seidel, S.; Sommer, M.; Spiegel, H.; Thumm, U.; Urbatzka, P.; Zimmer, J.; Kögel-Knabner, I.; Wiesmeier, M. |
| Journal / Serie | Geoderma |
| Erscheinungsjahr | 2023 |
| Department | BZF |
| Band/Volume | 434 |
| Seite von | art. 116472 |
| Sprache | englisch |
| Topic | T5 Future Landscapes |
| Supplements | https://ars.els-cdn.com/content/image/1-s2.0-S0016706123001490-mmc1.docx |
| Keywords | Fractionation; Mixed-effects modeling; Fertilization; Crop rotation; POM-C / MAOM-C ratio indicator |
| Abstract | Soil organic matter (SOM) is indispensable for soil health and, in the context of climate change, is considered a significant CO2 sink. Improving agricultural management to increase long-term soil organic carbon (SOC) stocks for mitigating climate change requires tools that estimate short and long-cycling SOM pools. In this study, we analyzed changes in fast-cycling particulate organic matter (POM) and slow-cycling mineral-associated organic matter (MAOM) induced by common management practices, i.e., fertilization and crop rotation in topsoils from 25 Central European long-term field experiments. When relating MAOM-C contents to recent MAOM-C saturation levels, estimated sequestration potentials were only met in coarse-textured soils under appropriate agricultural management or fine-textured soils under extreme organic fertilization. Soil texture, organic fertilization, and below-ground OC inputs through root exudates and root biomass were decisive for estimating MAOM-C, allowing for calibration of a mixed-effects model (Nakagawa’s: marginal R2m = 0.6, conditional R2c = 0.89). While the models containing soil texture and organic fertilization parameters can be validated and generalized (R2 = 0.43), the below-ground OC input predictor substantially decreases the generalizability of the validated models (R2 = 0.14). According to quantile regression models, we estimate the average difference in MAOM-C concentration between well-managed and control site (without organic fertilization) topsoils to 4.1 mg g−1 soil. In dependence on the soil bulk density, this amounts to 1.38 – 1.84 t ha−1 MAOM-C stocks or 5.06 – 10.1 t ha−1 CO2-equivalents. POM-C was difficult to predict (R2 = 0.28), presumably due to strong POM dynamics. The POM-C / MAOM-C ratio can inform on the effects of agricultural practices in before/after management change comparisons. Under increasing SOC concentration, an increasing POM-C / MAOM-C ratio indicates that the effects of organic fertilization do not transfer to real effects on long-term SOC sequestration. Because MAOM-C depends on soil texture, this ratio is also a covariate of soil texture, limiting it for comparisons between sites with different textures. However, our data indicate that agricultural long-term field experiment soils constantly approximate MAOM-C saturation when the POM-C/MAOM-C ratio is >0.35. This ratio might be used as a management goal to prevent organic over-fertilization and N loss, especially on coarse-textured soils. Thereby, the POM-C / MAOM-C ratio can help to optimize SOC management and sequestration on agricultural soils and support climate change mitigation strategies in Central Europe. |
| dauerhafte UFZ-Verlinkung | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=22709 |
| Just, C., Armbruster, M., Barkusky, D., Baumecker, M., Diepolder, M., Döring, T.F., Heigl, L., Honermeier, B., Jate, M., Merbach, I., Rusch, C., Schubert, D., Schulz, F., Schweitzer, K., Seidel, S., Sommer, M., Spiegel, H., Thumm, U., Urbatzka, P., Zimmer, J., Kögel-Knabner, I., Wiesmeier, M. (2023): Soil organic carbon sequestration in agricultural long-term field experiments as derived from particulate and mineral-associated organic matter Geoderma 434 , art. 116472 |
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