农业废弃物制备的生物质炭对红壤酸度和油菜产量的影响

利用自行研制的生物质炭化炉在田间条件下制备花生秸秆炭和油菜秸秆炭,采集秸秆气化站产生的稻壳炭,研究了这3种生物质炭对酸性土壤的改良效果和对油菜产量的影响。结果表明:施用稻壳炭、花生秸秆炭和油菜秸秆炭均可提高土壤p H,降低土壤交换性酸含量,效果随施用量的增加而增强。生物质炭对酸性土壤的改良效果主要决定于其本身的含碱量,施用花生秸秆炭和油菜秸秆炭显著增加土壤交换性盐基阳离子、有效磷、有效阳离子交换量和盐基饱和度,并提高油菜籽产量。田间条件下施用花生秸秆炭和油菜秸秆炭3年后土壤p H仍明显高于对照处理,说明生物质炭对土壤酸度的改良具有持续性。因此,花生秸秆炭和油菜秸秆炭是优良的酸性土壤改良剂。

Amelioration Effects of Crop Residue-derived Biochars on Soil Acidity and Canola Yield in Red Soil

Peanut straw and canola straw biochars produced with self-made biomass carbonization furnace and rice hell biochar collected from a gas gasification station were used to investigate amelioration effects of crop residue-derived biochars on soil acidity and canola yield in red soil. Results indicated that the application of all the three materials effectively increased soil pH and decreased soil exchangeable acidity. The amelioration effects of the biochars were primarily dependent on their alkalinity. Application of peanut straw and canola straw biochars significantly increased soil exchangeable base cations, available phosphorus, effective cation exchange capacity and base saturation, and thus increased the canola yield under field conditions. Soil pH for the treatments with peanut straw and canola straw biochars applied still higher than that for the control after 3 years of the soil amended with the biochars, suggesting that the ameliorating effect of the biochars on red soil is lasting. The amelioration effect on soil acidity and fertility in the red soil intensified with the application rates. Thus, peanut straw and canola straw biochars are good amendments for acid red soils.