Liu Meng, Tan Xiao, Zheng Mingxia, Yu Dayang, Lin Aijun, Liu Jiaoxian, Wang Chunyan, Gao Zhiyun, Cui Jun
College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing, 100012, China.
J Environ Manage. 2023 Jan 1;325(Pt A):116614. doi: 10.1016/j.jenvman.2022.116614. Epub 2022 Nov 1.
Fertile and uncontaminated soil with appropriate pH is crucial in terms of the agricultural sustainable development. Herein, a compound soil conditioner containing chitosan modified straw biochar (CBC), kitchen waste compost product-derived humic substance (HS), NPK compound fertiliser (NPK-CF) was prepared to simultaneously adjust acidic soil pH, improve fertility, and immobilize heavy metal. The results exhibited that the best Pb and NH adsorption performance was obtained in CBC with chitosan:biochar of 1:5. Then, the acid soil pH was improved from 5.03 to 6.66 in the presence of CBC/HS (5:5) with 3% addition weight (the mass ratio of conditioner to soil). Meanwhile, compared with the control, the contents of organic matter, available nitrogen, and available phosphorus significantly increased by 52.4%, 92.6%, and 136.3%, respectively. Moreover, Pb was highly efficient immobilised by CBC, and the concentration of Pb in the soil was decreased by 55.2%. The optimal growth trend of ryegrass was obtained in the presence of 3% addition weight (the mass ratio of conditioner to soil) CBC/HS (CBC:HS = 5:5) combined with 60% of the recommended NPK-CF application weight, which was mainly contributed by the improvement of the soil microbial abundance and community structure diversity. The addition of CBC/HS could effectively reduce the addition of NPK-CF and contribute to simultaneous controlling nitrogen loss, releasing phosphorus, immobilising Pb, adjusting pH, improving soil quality and controlling nonpoint pollution.
具有适宜pH值的肥沃且未受污染的土壤对于农业可持续发展至关重要。在此，制备了一种复合土壤改良剂，其包含壳聚糖改性秸秆生物炭（CBC）、厨余堆肥产品衍生的腐殖质（HS）、氮磷钾复合肥（NPK - CF），以同时调节酸性土壤pH值、提高肥力并固定重金属。结果表明，壳聚糖与生物炭比例为1:5的CBC对铅和氨具有最佳吸附性能。然后，在添加3%（改良剂与土壤的质量比）的CBC/HS（5:5）时，酸性土壤的pH值从5.03提高到了6.66。同时，与对照相比，有机质、有效氮和有效磷的含量分别显著增加了52.4%、92.6%和136.3%。此外，CBC对铅的固定效果显著，土壤中铅的浓度降低了55.2%。在添加3%（改良剂与土壤的质量比）的CBC/HS（CBC:HS = 5:5）并结合60%推荐施用量的NPK - CF时，黑麦草呈现出最佳生长趋势，这主要得益于土壤微生物丰度和群落结构多样性的改善。添加CBC/HS可以有效减少NPK - CF的施用量，并有助于同时控制氮素流失、释放磷、固定铅、调节pH值、改善土壤质量和控制面源污染
