Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, 712100 Yangling, Shaanxi, China; College of Water Resources and Architectural Engineering, Northwest A&F University, Weihui Road 23, 712100 Yangling, Shaanxi, China; Department of Agroecology, Aarhus University, Blichers Allé 20, 8830 Tjele, Denmark.
Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, 712100 Yangling, Shaanxi, China; College of Water Resources and Architectural Engineering, Northwest A&F University, Weihui Road 23, 712100 Yangling, Shaanxi, China.
Sci Total Environ. 2022 Feb 1;806(Pt 1):150513. doi: 10.1016/j.scitotenv.2021.150513. Epub 2021 Sep 22.
Biochar has been advocated as a sustainable and eco-friendly practice to improve soil fertility and crop productivity which could aid in the mitigation of climate change. Nonetheless, the combined effects of biochar and irrigation on tobacco growth and soil nutrients in diverse soil types have been incompletely explored. We applied a split-root experiment to investigate the impacts of amendment with 2% softwood- (WBC) and wheat-straw biochar (SBC) on growth responses and rhizosphere soil nutrients availability of tobacco plants grown in a Ferralsol and an Anthrosol. All plants within same soil type received same amount of water daily by either conventional deficit irrigation (CDI) or alternate wetting-drying cycles irrigation (AWD). Compared to the un-amended controls, SBC addition enhanced biomass, carbon (C)-, phosphorus (P)- and potassium (K)-pool in the aboveground organs especially in Anthrosol, despite a negative effect on aboveground nitrogen (N)-pool. Regardless of soil type, biochar combined with AWD lowered root diameter while increased root tissue mass density to engage the plant in an acquisitive strategy for resources, therefore altered leaves stoichiometry as exemplified by lowered N/K, C/P and N/P and increased C/N. The addition of SBC induced a liming effect by increasing Anthrosol soil pH which was further amplified by AWD, but was unaffected on Ferralsol. Moreover, compared to the controls, SBC and AWD increased available P and K, and total C, total N and C/N ratio in the rhizosphere soil which coincided with the lowered soil C and N isotope composition (δC and δN), though a slight reduction in C and N stocks under AWD. However, such effects were not evident with WBC might be associated with its natures. Thus, combined SBC/AWD application might be an effective strategy to synergistically overcome nutrients restriction and improve tobacco productivity by intensifying nutrients cycling and optimizing plant growth strategies.
生物炭被提倡为一种可持续和环保的做法，以提高土壤肥力和作物生产力，从而有助于减缓气候变化。然而，生物炭和灌溉对不同土壤类型中烟草生长和土壤养分的综合影响尚未得到充分探索。我们应用分根实验来研究 2%软木-（WBC）和小麦秸秆生物炭（SBC）对在 Ferralsol 和 Anthrosol 中生长的烟草植物生长响应和根际土壤养分供应的影响。在同一土壤类型中，所有植物每天都通过常规亏缺灌溉（CDI）或交替湿润-干燥循环灌溉（AWD）接受相同数量的水。与未施肥对照相比，SBC 的添加增加了地上器官的生物量、碳（C）、磷（P）和钾（K）库，特别是在 Anthrosol 中，尽管对地上氮（N）库有负面影响。无论土壤类型如何，生物炭与 AWD 结合都会降低根直径，同时增加根组织质量密度，使植物采用资源获取策略，从而改变叶片化学计量比，例如降低 N/K、C/P 和 N/P 以及增加 C/N。SBC 的添加通过增加 Anthrosol 土壤 pH 值产生了石灰化效应，AWD 进一步放大了这种效应，但对 Ferralsol 没有影响。此外，与对照相比，SBC 和 AWD 增加了根际土壤中有效磷和钾以及总 C、总 N 和 C/N 比，同时降低了土壤 C 和 N 同位素组成（δC 和 δN），尽管 AWD 下 C 和 N 储量略有减少。然而，WBC 没有明显的效果，可能与其性质有关。因此，SBC/AWD 的联合应用可能是一种有效的策略，可以通过加强养分循环和优化植物生长策略来协同克服养分限制并提高烟草生产力。
