Kuang Xi-Zhi, Deng Wei-Ming, Tang Le-le, Huang Qi, Cai Kun-Zheng, Tian Ji-Hui
Guangdong Provincial Key Laboratory of Eco-Circular Agriculture, Guangzhou 510642, China.
College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China.
Ying Yong Sheng Tai Xue Bao. 2022 Jul;33(7):1911-1918. doi: 10.13287/j.1001-9332.202207.018.
Biochar is beneficial to soil phosphorus (P) availability and crop growth, but the effects vary greatly across different soil types. We investigated the effects of rice straw biochar (4% of total mass) and P application (0, 30, and 90 kg P·hm) on soil P availability, phosphomonoesterase activity, and soybean P uptake by using lateritic red soil (pH 4.91) and cinnamon soil (pH 7.24) as test materials. The results showed that biochar application at different P levels significantly increased available P and total P in both soils. Biochar application with 30 kg P·hm increased soil available P with maxima at 192.6% and 237.1% in lateritic red soil and cinnamon soil, respectively. Biochar application with 30 kg P·hm in lateritic red soil significantly increased the activity of alkaline phosphomonoesterase by 78.9%, decreased the content of active organic P by 39.3%, and subsequently stimulated soybean P absorption and growth. Biochar amendment significantly reduced active organic P content in cinnamon soil, but did not affect soil phosphomonoesterase activity and plant growth. The content of active organic P was significantly negatively correlated with soil available P content. In summary, the effect of biochar on soil P availability varied across different soil types (lateritic red soil > cinnamon soil) and P levels (better at 30 kg P·hm). Our results could provide scientific basis for a promising application of biochar in reducing the amount of P fertilizer and increasing soybean P uptake, especially in lateritic red soil.
生物炭有利于提高土壤磷（P）有效性和作物生长，但不同土壤类型的效果差异很大。我们以赤红壤（pH 4.91）和黄棕壤（pH 7.24）为试验材料，研究了稻草生物炭（占总质量的4%）和施磷量（0、30和90 kg P·hm²）对土壤磷有效性、磷酸单酯酶活性和大豆磷吸收的影响。结果表明，在不同磷水平下施用生物炭均显著提高了两种土壤的有效磷和全磷含量。在赤红壤和黄棕壤中，施30 kg P·hm²生物炭分别使土壤有效磷含量最高增加了192.6%和237.1%。在赤红壤中施30 kg P·hm²生物炭显著提高了碱性磷酸单酯酶活性78.9%，降低了活性有机磷含量39.3%，进而促进了大豆对磷的吸收和生长。生物炭改良显著降低了黄棕壤中活性有机磷含量，但对土壤磷酸单酯酶活性和植物生长没有影响。活性有机磷含量与土壤有效磷含量呈显著负相关。综上所述，生物炭对土壤磷有效性的影响因土壤类型（赤红壤>黄棕壤）和磷水平（30 kg P·hm²效果较好）而异。我们的研究结果可为生物炭在减少磷肥用量和增加大豆磷吸收方面的应用提供科学依据，特别是在赤红壤中。
