Li Shuai, Zhang Dongliang, Wang Yumei, Wu Jihua, Shi Guoli, Zhang Yuhua, Wang Fayuan
Shangqiu Academy of Agriculture and Forestry Sciences, Shangqiu, China.
Henan Huangfanqu Dishen Seeds Co., Ltd, Zhoukou, China.
Int J Phytoremediation. 2025 Jul 23:1-9. doi: 10.1080/15226514.2025.2532754.
Sweet sorghum has a high tolerance to toxic metals, but its response to soil amendments in Cd-polluted soils remains underexplored. Here, we compared the effects of biochar and hydroxyapatite (HAP) at different doses (0, 0.5%, and 1%, w/w) on the growth, mineral nutrition, stress tolerance, and phytoremediation efficiency of sweet sorghum grown in an agricultural soil heavily polluted by Cd (20.80 mg/kg). In most cases, both amendments greatly increased plant biomass and nutrient uptake of N, P, and K, and enhanced the activities of antioxidative enzymes (peroxidase and superoxide dismutase) in leaves. They also increased soil pH and reduced soil available Cd concentrations, confirming their liming effects and immobilization of Cd. Unexpectedly, both HAP and biochar significantly increased Cd concentration and uptake in the shoots and roots, contradicting prior findings. Shoot Cd uptake was increased by 96% and 57% by 0.5% and 1% biochar, respectively. Root Cd uptake was increased by 50% and 64% by 1% HAP and 0.5% biochar, respectively. Overall, both HAP and biochar improved sweet sorghum growth and mitigated Cd toxicity, and particularly, decreased soil Cd availability while enhancing shoot and root Cd accumulation, indicating a promising strategy for the phytoextraction and phytostabilization of Cd-polluted soils.
甜高粱对有毒金属具有较高的耐受性，但其在镉污染土壤中对土壤改良剂的响应仍未得到充分研究。在此，我们比较了不同剂量（0%、0.5%和1%，w/w）的生物炭和羟基磷灰石（HAP）对生长在镉重度污染（20.80 mg/kg）农业土壤中的甜高粱的生长、矿质营养、胁迫耐受性和植物修复效率的影响。在大多数情况下，两种改良剂都显著增加了植物生物量以及氮、磷和钾的养分吸收，并增强了叶片中抗氧化酶（过氧化物酶和超氧化物歧化酶）的活性。它们还提高了土壤pH值并降低了土壤有效镉浓度，证实了它们的调酸作用和对镉的固定作用。出乎意料的是，HAP和生物炭都显著增加了地上部和根部的镉浓度及吸收量，这与先前的研究结果相矛盾。0.5%和1%的生物炭分别使地上部镉吸收量增加了96%和57%。1%的HAP和0.5%的生物炭分别使根部镉吸收量增加了50%和64%。总体而言，HAP和生物炭都改善了甜高粱的生长并减轻了镉毒性，特别是降低了土壤镉的有效性，同时增加了地上部和根部的镉积累，这表明这是一种用于镉污染土壤植物提取和植物稳定化的有前景的策略。
