Wang Yong, Sun Yanni, Chen Le, Shao Hua, Zeng Yanhua, Zeng Yongjun, Tang Feiyu, Cai Junhuo, Huang Shan
Ministry of Education Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Jiangxi Agricultural University, Nanchang, 330045, China.
Soil and Fertilization Technology Extension Station of Jiangxi Province, Nanchang, 330046, China.
Environ Sci Pollut Res Int. 2023 Jan;30(5):13551-13559. doi: 10.1007/s11356-022-23162-x. Epub 2022 Sep 22.
Rice agriculture is both an important source of the potent greenhouse gas methane (CH) and a bioaccumulator of cadmium (Cd), which is hazardous to human health. Avoiding flooding during rice production is effective for reducing CH emissions, but it increases rice Cd uptake. Although lime application decreases Cd concentration in rice grains, it is not clear whether combining appropriate water management with liming can simultaneously reduce CH emissions and Cd uptake in rice paddies. Thus, a pot experiment was performed to investigate the interactive effects of water management (F: continuous flooding, FDF: flooding - midseason drainage - flooding, FDI: flooding - midseason drainage - intermittent irrigation) and lime application on CH emissions and rice Cd uptake in an acid paddy soil spiked with Cd. Results showed that neither water management nor liming significantly affected grain yield. Overall, liming reduced CH emissions by 42.2%. Compared to F, the FDF and FDI treatments reduced CH emissions by 43.5% and 54.2%, respectively. Liming reduced CH emissions by 32.6% under F, but with a greater decrease of 48.6% and 52.7% under FDF and FDI, respectively. Overall, liming reduced rice Cd uptake by an average of 47.3%. Compared to FDI, F and FDF significantly reduced Cd uptake by 84.0% and 75.1%, respectively, but there was no significant difference between F and FDF. Liming did not significantly affect Cd uptake under F and FDF, whereas liming reduced Cd uptake by 55.9% under FDI. These results suggest that maintaining flooding following midseason drainage can help in reducing rice Cd uptake, though slightly promoting CH emissions. Therefore, we recommend FDF combined with liming to mitigate CH emissions without increasing rice Cd uptake in acid paddy soils.
水稻种植既是强效温室气体甲烷（CH₄）的重要排放源，也是镉（Cd）的生物蓄积源，而镉对人体健康有害。在水稻生产过程中避免淹水对于减少CH₄排放是有效的，但会增加水稻对镉的吸收。虽然施用石灰能降低稻米中的镉浓度，但尚不清楚将适当的水分管理与施用石灰相结合是否能同时减少稻田CH₄排放和水稻对镉的吸收。因此，进行了一项盆栽试验，以研究水分管理（F：持续淹水、FDF：淹水-生育中期排水-淹水、FDI：淹水-生育中期排水-间歇灌溉）和施用石灰对添加镉的酸性稻田土壤中CH₄排放和水稻镉吸收的交互作用。结果表明，水分管理和施用石灰均未显著影响粮食产量。总体而言，施用石灰使CH₄排放量降低了42.2%。与F处理相比，FDF和FDI处理的CH₄排放量分别降低了43.5%和54.2%。在F处理下，施用石灰使CH₄排放量降低了32.6%，但在FDF和FDI处理下分别有更大幅度的降低，即48.6%和52.7%。总体而言，施用石灰使水稻对镉的吸收平均降低了47.3%。与FDI处理相比，F和FDF处理分别使镉吸收量显著降低了84.0%和75.1%，但F和FDF之间没有显著差异。在F和FDF处理下，施用石灰对镉吸收没有显著影响，而在FDI处理下，施用石灰使镉吸收量降低了55.9%。这些结果表明，生育中期排水后保持淹水有助于减少水稻对镉的吸收，尽管会略微促进CH₄排放。因此，我们建议在酸性稻田土壤中采用FDF处理并结合施用石灰，以在不增加水稻镉吸收的情况下减轻CH₄排放。
