Department of Mineralogy and Petrology, Science and Technology Faculty, University of the Basque Country (UPV/EHU), Apartado 644, E-48080 Bilbao, Spain; NEIKER-Tecnalia, Department of Conservation of Natural Resources, 812 Bizkaia Science and Technology Park, E-48160 Derio, Spain; European Commission, Joint Research Centre (JRC), Directorate D - Sustainable Resources, Land Resources, Via E. Fermi 2749, I-21027 Ispra (VA), Italy.
NEIKER-Tecnalia, Department of Conservation of Natural Resources, 812 Bizkaia Science and Technology Park, E-48160 Derio, Spain.
Sci Total Environ. 2017 Jun 1;587-588:204-213. doi: 10.1016/j.scitotenv.2017.02.121. Epub 2017 Feb 23.
Biochar can largely contribute to enhance organic carbon (OC) stocks in soil and improve soil quality in forest and agricultural lands. Its contribution depends on its recalcitrance, but also on its interactions with minerals and other organic compounds in soil. Thus, it is important to study the link between minerals, natural organic matter and biochar in soil. In this study, we investigated the incorporation of biochar-derived carbon (biochar-C) into various particle-size fractions with contrasting mineralogy and the effect of biochar on the storage of total OC in the particle-size fractions in an acid loamy soil under Pinus radiata (C3 type) in the Spanish Atlantic area. We compared plots amended with biochar produced from Miscanthus sp. (C4 type) with control plots (not amended). We separated sand-, silt-, and clay-size fractions in samples collected from 0 to 20-cm depth. In each fraction, we analyzed clay minerals, metallic oxides and oxy-hydroxides, total OC and biochar-C. The results showed that 51% of the biochar-C was in fractions <20μm one year after the application of biochar. Biochar-C stored in clay-size fractions (0.2-2μm, 0.05-0.2μm, <0.05μm) was only 14%. Even so, we observed that biochar-C increased with decreasing particle-size in clay-size fractions, as it occurred with the vermiculitic phases and metallic oxides and oxy-hydroxides. Biochar also affected to the distribution of total OC among particle-size fractions. Total OC concentration was greater in fractions 2-20μm, 0.2-2μm, 0.05-0.2μm in biochar-amended plots than in control plots. This may be explained by the adsorption of dissolved OC from fraction <0.05μm onto biochar particles. The results suggested that interactions between biochar, minerals and pre-existing organic matter already occurred in the first year.
生物炭可以大量增加土壤中的有机碳（OC）储量，改善森林和农业土地的土壤质量。其贡献取决于其稳定性，但也取决于其与土壤中矿物质和其他有机化合物的相互作用。因此，研究土壤中矿物质、天然有机质和生物炭之间的联系非常重要。在这项研究中，我们研究了生物炭衍生碳（biochar-C）在具有不同矿物学特性的不同粒径分馏物中的掺入情况，以及生物炭对酸性壤土中总 OC 在颗粒分馏物中储存的影响，该土壤位于西班牙大西洋地区辐射松（C3 型）下。我们将用 Miscanthus sp.（C4 型）生产的生物炭改良的地块与对照地块（未改良）进行了比较。我们从 0 到 20 厘米深度的样品中分离出砂、粉砂和粘粒级分。在每个分级中，我们分析了粘土矿物、金属氧化物和氢氧化物、总 OC 和 biochar-C。结果表明，在施用生物炭一年后，51%的 biochar-C 存在于<20μm 的级分中。储存在粘粒级分（0.2-2μm、0.05-0.2μm、<0.05μm）中的 biochar-C 仅为 14%。即便如此，我们观察到，与蛭石相和金属氧化物及氢氧化物一样，随着粘粒级分粒径的减小，biochar-C 也会增加。生物炭还影响总 OC 在颗粒级分中的分布。在生物炭改良的地块中，总 OC 浓度在 2-20μm、0.2-2μm 和 0.05-0.2μm 级分中大于对照地块。这可能是由于来自<0.05μm 级分的溶解 OC 被吸附到生物炭颗粒上所致。结果表明，在第一年，生物炭、矿物质和现有有机质之间就已经发生了相互作用。
