College of Environmental Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, 225127, PR China; Department of Animal, Plant and Soil Sciences, Centre for AgriBioscience, La Trobe University, Melbourne, VIC, 3086, Australia.
College of Environmental Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, 225127, PR China.
Chemosphere. 2022 Dec;308(Pt 2):136347. doi: 10.1016/j.chemosphere.2022.136347. Epub 2022 Sep 7.
Biochar application is a potent climate change mitigation strategy in agroecosystems. However, little is known about the interactive effects of elevated CO (eCO) and biochar on plant nutrient uptake and soil microbial processes. A pot experiment was conducted to investigate the effects of eCO and biochar addition on plant C:N:P stoichiometry and rhizobacterial community for better management of nutrient balance and use efficiency in a future climate scenario. White lupin (Lupinus albus L.) was grown for 30 days in topsoil and subsoil with or without 2% corn-stubble biochar under ambient CO (aCO: 390 ppm) or eCO (550 ppm). Elevated CO increased, but biochar decreased, plant biomass and shoot N and P uptake, with no interactions in either soil layer. Elevated CO decreased shoot N concentration by 16% and biochar decreased shoot P concentration by 11%. As a result, eCO increased shoot C:N ratio by 20% and decreased the N:P ratio by 11%. Biochar decreased shoot C:N ratio by 8% in the subsoil under eCO. However, biochar increased shoot C:P ratio by an average of 13% and N:P ratio by 23% in the subsoil. Moreover, plants grown in the subsoil showed lower shoot N (35%) and P (70%) uptake compared to the topsoil. The results indicate that N and P are the more limiting factors that regulate plant growth under eCO and biochar application, respectively. Elevated CO and biochar oppositely affected dominant rhizobacterial community composition, with the eCO effect being greater. The microbiota in the subsoil held a greater diversity of contrasting species than the topsoil, which were associated with nutrient cycling, hydrocarbon degradation and plant productivity. These results enrich our understanding of potential soil nutrient cycling and plant nutrient balance in future agroecosystems.
生物炭的应用是农业生态系统中一种有效的减缓气候变化的策略。然而，对于升高的 CO（eCO）和生物炭对植物养分吸收和土壤微生物过程的交互影响知之甚少。本试验通过盆栽试验研究了 eCO 和生物炭添加对植物 C:N:P 化学计量和根际细菌群落的影响，以期在未来气候情景下更好地管理养分平衡和利用效率。在常 CO（aCO：390 ppm）或 eCO（550 ppm）条件下，在表土和底土中添加或不添加 2%玉米秸秆生物炭，种植白 Lupinus albus L.30 天。升高的 CO 增加了，但生物炭减少了植物生物量和地上部 N 和 P 的吸收，在两个土层中均无交互作用。升高的 CO 使地上部 N 浓度降低 16%，生物炭使地上部 P 浓度降低 11%。结果，eCO 增加了地上部 C:N 比 20%，降低了 N:P 比 11%。在 eCO 下，生物炭使底土地上部 C:N 比降低 8%。然而，生物炭使底土地上部 C:P 比平均增加 13%，N:P 比增加 23%。此外，与表土相比，生长在底土中的植物地上部对 N（35%）和 P（70%）的吸收较低。结果表明，在 eCO 和生物炭应用下，N 和 P 分别是限制植物生长的更重要因素。升高的 CO 和生物炭对优势根际细菌群落组成的影响相反，eCO 的影响更大。与表土相比，底土中的微生物具有更大的多样性和相反的物种，这些物种与养分循环、碳氢化合物降解和植物生产力有关。这些结果丰富了我们对未来农业生态系统中潜在土壤养分循环和植物养分平衡的理解。
