Soil organic matter serves as a crucial indicator for soil quality. Albic soil, characterized by a barrier layer, exhibits limitations in organic matter content, which can adversely affect crop growth and development. To elucidate the impact of deep mixing of various organic materials on the redistribution of organic matter in the surface soil of albic soil could provide theoretical and technical insights for establishing suitable plough layers for albic soil in Northeast China. We conducted a two-year positioning experiment in Shuangyashan, Heilongjiang Province with five treatments, conventional shallow tillage (0-15 cm, CK), inversion tillage (0-35 cm) without or with straw return (T35 and T35+S), inversion tillage with cattle
manure (T35+M) and cattle
manure plus maize straw (T35+S+M). The results showed that soil fertilization via deep mixing of organic materials to a depth of 35 cm significantly increased maize yield in albic soil, with the T35+S+M treatment demonstrating the most pronounced effect, yielding an average production of 2934.76 kg·hm-2. Compared to CK, the T35 treatment resulted in a significant 8.4% decrease in organic matter content in the tillage layer, a significant 7.6% increase in organic matter in the sub-tillage layer, and a relative richness degree of soil organic matter in the sub-tillage layer increased by 17.5%. Deep mixed return of organic materials following deep ploughing markedly increased organic matter content of the plough layer, with organic matter conversion ranging from 16.3% to 31.0%. In comparison to the T35 treatment, there was no significant increase in soil organic matter content in the T35+S tillage layer and sub-tillage layer. Conversely, soil organic matter content increased by 4.6% and 6.9% in the T35+M and T35+S+M treatments, with corresponding increase of 11.2% and 15.4% in sub-tillage layer, respectively. Additionally, the soil organic matter richness index in sub-tillage layer increased by 2.5% and 5.1%, respectively. There was a significant positive correlation between organic matter content in the entire plough layer and maize yield, with a contribution rate of 17.5%. Therefore, the utilization of organic fertilizer or a combination of organic fertilizer and straw deep mixing can quickly fertilize albic soil by increasing soil organic matter content in both the whole tillage layer (0-35 cm) and the sub-tillage layer (15-35 cm).
土壤有机质是表征土壤质量的重要指标,白浆土作为具有典型障碍层的土壤,其低有机质含量易对作物生长发育产生不良影响,明确不同有机物料深混对白浆土表层土壤有机质再分布的影响,可为东北农田白浆土构建适宜的耕层提供理论和技术参考。本研究在黑龙江省双鸭山市白浆土上进行了为期2年的定位试验,设置5种处理:深翻35 cm(T35)、秸秆深混35 cm(T35+S)、有机肥深混35 cm(T35+M)、秸秆搭配有机肥深混35 cm(T35+S+M),以农民常规措施(浅翻15 cm,CK)为对照。结果表明: 有机物料深混35 cm还田处理(T35+S、T35+M和T35+S+M)可显著提升玉米产量,其中以T35+S+M处理对玉米产量的提升效果最显著,2年平均增产2934.76 kg·hm-2。与CK相比,T35处理耕层(0~15 cm)土壤有机质含量降低8.4%,而亚耕层(15~35 cm)土壤有机质含量增加7.6%,亚耕层土壤有机质丰富度指数增加17.5%。在深翻基础上有机物料还田可显著提升全耕层(0~35 cm)土壤有机质含量,全耕层土壤有机质转化率为16.3%~31.0%。与T35处理相比,T35+S处理耕层和亚耕层土壤有机质含量无显著增加,T35+M和T35+S+M处理耕层土壤有机质含量分别显著增加4.6%和6.9%,亚耕层土壤有机质含量分别显著增加11.2%和15.4%,亚耕层土壤有机质丰富度指数分别增加2.5%和5.1%。相关性分析表明,全耕层土壤有机质含量与玉米产量呈显著正相关,贡献率达17.5%。综上,有机肥或有机肥配合秸秆深混还田是培肥白浆土的有效措施,且主要是通过提升全耕层(0~35 cm)与亚耕层(15~35 cm)土壤有机质含量实现。.