Effects of biochar-based soil conditioners on ameliorating acid soil in vegetable field

Abstract

为研究不同配比生物炭基土壤调理剂对酸性菜田土的改良效果，以生石灰、粉煤灰、钢渣和生物炭为原料，通过盆栽试验研究4种原料不同配比生物炭基土壤调理剂对酸性菜田土壤的改良效果及对油麦菜养分吸收、产量的影响。试验采用4因素3水平正交试验。生石灰、粉煤灰、钢渣用量水平为0、2.5、5.0g·kg^-1，生物炭用量水平为0、25.0、50.0g·kg^-1，共9个处理，每个处理设4次重复。结果表明：施用不同配比生物炭基土壤调理剂后，土壤pH显著提高0.82~1.75个单位，土壤交换性钙、阳离子交换量（CEC）分别显著增加38.52%~122.63%、41.10%~78.65%（P<0.05）；土壤微生物丰富度提高，其中溶杆菌属（Lysobacter）、马赛菌属（Massilia）等微生物增加最为明显；油麦菜对N、P、K的吸收量增加7.94%~64.79%，产量增幅达8.03%~16.68%；土壤碱解氮含量显著降低，土壤脲酶和过氧化氢酶活性变化不显著；施用适宜配比的生物炭基土壤调理剂后，土壤有机质、全氮、有效磷、速效钾、交换性镁含量以及土壤磷酸酶和蔗糖酶活性均有不同程度的提高。研究表明，生物炭基土壤调理剂对酸性菜田土壤具有良好的改良效果，当生石灰、粉煤灰、钢渣和生物炭的施用量分别为5.0、2.5、5.0g·kg^-1和50.0g·kg^-1时效果最佳。

This study is to explore the effects of different biochar-based soil conditioners on the amelioration of acidic soil in vegetable fields. Using quicklime, fly ash, steel slag, and biochar as raw materials, nine biochar-based soil conditioners were prepared by employing an orthogonal test of four factors and three levels. The dosages of lime, fly ash, and steel slag were 0, 2.5 g·kg^-1, and 5.0 g·kg^-1, and the dosages of biochar were 0, 25.0 g·kg^-1, and 50.0 g·kg^-1. A pot experiment was conducted to study the effects of these soil conditioners on soil quality, vegetable yield, and nutrient uptake with four replicates. With the application of different biochar-based soil conditioners, soil pH, soil exchangeable Ca, and soil cation exchange capacity（CEC） significantly（P<0.05） increased by 0.82-1.75 units, 38.52%-122.63%, and 41.10%-78.65%, respectively. Soil microbial abundance was promoted, especially for Lysobacter and Massilia. The uptake of N, P, and K by lettuce increased by 7.94%-64.79%, and lettuce yield increased by 8.03%-16.68%. However, the soil's alkaline hydrolysis nitrogen content decreased significantly. There were no significant effects of treatments on soil urease or catalase activity. The contents of soil organic matter, total N, available P, available K, and exchangeable Mg, and the activities of soil phosphatase and invertase all increased upon the addition of soil conditioners with proper material ratios. Biochar-based soil conditioners were effective at ameliorating acidic soil in vegetable fields. The optimal combination of quicklime, fly ash, steel slag, and biochar involved an input of 5.0, 2.5, 5.0 g·kg^-1, and 50.0 g·kg^-1, respectively.