State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China.
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China; Institute of Soil and Water Conservation, CAS and MWR, Yangling, Shaanxi Province 712100, PR China.
Sci Total Environ. 2019 Feb 1;649:1403-1413. doi: 10.1016/j.scitotenv.2018.08.415. Epub 2018 Aug 30.
Increasing literature suggests that biochar can be used to improve soil fertility and subsequently benefit crop yield. However, the effects of biochar application rates and particle sizes on soil erosion processes have yet to be fully identified. The objective of the present study was to evaluate the influence of biochar with different application rates and particle sizes on soil erosion. Addition of biochar to loess generally increased the mean time to runoff by 19.47% relative to the control. The time to runoff decreased with an increase in the biochar application rates and fluctuated with a decrease in biochar particle sizes. The combined 1% and <0.25 mm biochar treatment yielded the longest time to runoff (2.97 min) and the lowest runoff (36.23 kg m h) and soil loss (1.33 kg m min). Biochar addition decreased the total runoff volume by 12.21% and generally inhibited soil loss under lower application rates (1% and 3%) while promoting soil loss under higher application rates (5% and 7%). With a decrease in biochar particle size, total runoff volume increased under the 5% and 7% biochar, but no uniform trend was observed under the 1% and 3% biochar treatments. The total soil loss increased with increasing biochar application rates, whereas a negative trend was observed with decreasing biochar particle sizes. The contribution of biochar application rates to runoff and soil loss rates was distinctly greater than the biochar particle sizes. Additionally, biochar addition could increase >2 mm water-stable soil aggregates and saturated hydraulic conductivity (K) in this study. We inferred that the positive effects on soil and water loss were potentially due to the improvement in >2 mm water-stable soil aggregates and K. The results implied that soil-biochar additions could be a potential measure for conserving soil and water in the Loess Plateau.
越来越多的文献表明，生物炭可以用来提高土壤肥力，从而提高作物产量。然而，生物炭施用量和粒径对土壤侵蚀过程的影响尚未完全确定。本研究旨在评估不同施用量和粒径的生物炭对土壤侵蚀的影响。与对照相比，生物炭添加到黄土中通常会使径流开始时间平均增加 19.47%。随着生物炭施用量的增加，径流开始时间减少，而随着生物炭粒径的减小，径流开始时间波动。1%和<0.25mm 的生物炭联合处理产生最长的径流开始时间（2.97min）和最低的径流（36.23kg·m-2·h-1）和土壤流失（1.33kg·m-2·min-1）。生物炭添加减少了 12.21%的总径流量，在较低施用量（1%和 3%）下通常抑制土壤流失，而在较高施用量（5%和 7%）下促进土壤流失。随着生物炭粒径的减小，在 5%和 7%的生物炭处理下总径流量增加，但在 1%和 3%的生物炭处理下没有观察到统一的趋势。总土壤流失量随生物炭施用量的增加而增加，而生物炭粒径的减小则呈负趋势。生物炭施用量对径流量和土壤流失率的贡献明显大于生物炭粒径。此外，本研究中添加生物炭可以增加>2mm 水稳性团聚体和饱和导水率（K）。我们推断，对土壤和水流失的积极影响可能是由于>2mm 水稳性团聚体和 K 的改善。结果表明，土壤-生物炭的添加可以成为黄土高原土壤和水保持的潜在措施。
