State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, P. O. Box 821, Nanjing 210008, China; Department of Environment Engineering, Henan University of Science and Technology, Luoyang 471023, China.
Department of Environment Engineering, Henan University of Science and Technology, Luoyang 471023, China.
Chemosphere. 2019 Mar;218:907-914. doi: 10.1016/j.chemosphere.2018.11.176. Epub 2018 Nov 27.
The types and amounts of cations and their uptake by plants vary with cultivating soils, which correlates with the carbonates and subsequent alkalis contents in the derived biochars. However, regional differences in the alkaline properties of crop straw biochars are unclear. In the present study, biochars pyrolyzed from canola straws collected from four different regions were used to assess the differences in the alkaline properties among them. The biochars were referred to as YTBC, XCBC, NJBC, and HYBC, respectively, and their feedstocks were collected from four different regions from south to north of China. The NHOAC exchangeable base cations (K, Na, Ca, Mg) in the biochars were 270.74, 1427.05, 2089.23, and 1516.48 mmol kg for YTBC, XCBC, NJBC, and HYBC, respectively, which were roughly consistent with the exchangeable base cations in the corresponding planting soils (17.57, 28.20, 151.26 and 444.65 mmol kg, respectively). The pH, carbonates content, and alkalinity of biochars considerably increased as follows: YTBC < XCBC < NJBC < HYBC. Wheat seedling root elongation experiment indicated that the Al(III) phytotoxicity alleviation effect of the biochars was as follows: HYBC > NJBC > XCBC > YTBC, which was corroborated by the subsequent findings of Evans blue staining, the remnant aluminum (Al(III)) in the reaction solution and Al(III) distribution in the wheat seedling roots. Thus, planting soil had a dominant influence in alleviating Al(III) phytotoxicity, and studies on crop straw biochar properties concerning alkalinities or liming potentials should not only consider crop genera and pyrolysis conditions, but also cultivating conditions.
油菜秸秆生物炭的碱性及其对 Al(III) 毒害的缓解效应
不同地区油菜秸秆生物炭的碱性及其对 Al(III) 毒害的缓解效应
生物炭的碱性与其对植物的阳离子吸收能力有关，而阳离子的种类和数量又与土壤中的碳酸盐及其衍生的生物炭中的碱度有关。然而，作物秸秆生物炭的碱性在不同地区之间的差异尚不清楚。本研究使用了来自中国四个不同地区的油菜秸秆制备的生物炭，以评估它们之间碱性性质的差异。这些生物炭分别被称为 YTBC、XCBC、NJBC 和 HYBC，它们的原料分别来自中国南方到北方的四个不同地区。生物炭中 NHOAC 可交换的碱金属阳离子（K、Na、Ca、Mg）分别为 270.74、1427.05、2089.23 和 1516.48 mmol kg-1，大致与相应种植土壤中的可交换碱金属阳离子（17.57、28.20、151.26 和 444.65 mmol kg-1）一致。生物炭的 pH 值、碳酸盐含量和碱度均随着以下顺序显著增加：YTBC < XCBC < NJBC < HYBC。小麦幼苗根系伸长实验表明，生物炭对 Al(III) 毒性的缓解效果如下：HYBC > NJBC > XCBC > YTBC，这一结果得到了 Evans 蓝染色实验、反应溶液中残留的铝（Al(III)）以及 Al(III)在小麦幼苗根系中分布的后续发现的证实。因此，种植土壤对缓解 Al(III) 毒性具有主导影响，而关于生物炭碱性或石灰化潜力的研究不仅应考虑作物种类和热解条件，还应考虑种植条件。
