Shi Ren-Yong, Hong Zhi-Neng, Li Jiu-Yu, Jiang Jun, Baquy M Abdulaha-Al, Xu Ren-Kou, Qian Wei
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences , P.O. Box 821, Nanjing 210008, P.R. China.
University of Chinese Academy of Sciences , Beijing 100049, P.R. China.
J Agric Food Chem. 2017 Sep 20;65(37):8111-8119. doi: 10.1021/acs.jafc.7b02266. Epub 2017 Sep 8.
The effects and underlying mechanisms of crop residue-derived biochars on the pH buffering capacity (pHbuff) of an acidic Ultisol, with low pHbuff, were investigated through indoor incubation and simulated acidification experiments. The incorporation of biochars significantly increased soil pHbuff with the magnitude of the increase dependent on acid buffering capacity of the biochar incorporated to the soil. Cation release, resulting from the protonation of carboxyl groups on biochar surfaces and the dissolution of carbonates, was the predominant mechanism responsible for the increase in soil pHbuff at pH 4.0-7.0 and accounted for >67% of the increased pHbuff. The reaction of protons with soluble silica (Si) in biochars derived from rice straw and corn stover also accounted for ∼20% of the pHbuff increase due to HSiO precipitation. In conclusion, the incorporation of crop residue-derived biochars into acidic soils increased soil pHbuff with peanut stover biochar being the most effective biochar tested.
通过室内培养和模拟酸化实验，研究了作物秸秆衍生生物炭对酸性低pH缓冲容量（pHbuff）的老成土pH缓冲容量（pHbuff）的影响及潜在机制。生物炭的添加显著提高了土壤pHbuff，增加幅度取决于添加到土壤中的生物炭的酸缓冲能力。生物炭表面羧基质子化和碳酸盐溶解导致的阳离子释放是pH值为4.0 - 7.0时土壤pHbuff增加的主要机制，占增加的pHbuff的67%以上。质子与稻草和玉米秸秆衍生生物炭中可溶性硅（Si）的反应也占因HSiO沉淀导致的pHbuff增加的约20%。总之，将作物秸秆衍生生物炭添加到酸性土壤中可提高土壤pHbuff，花生秸秆生物炭是测试的最有效生物炭。
