为揭示外源锌在绿洲盐化潮土中的转化特征，通过盆栽模拟试验，探究了盐渍条件下不同施锌量对玉米幼苗生长和锌形态转化的影响。结果表明，无论非盐渍条件还是盐渍条件下，随着施锌量的增加玉米的株高和干重均呈先增加后减小的趋势，施锌量为5～10 mg/kg时达到最大。玉米含锌量随施锌量的增加而增大，吸锌量随施锌量的增加先增大后减小，施锌量为10 mg/kg时达到最大。施锌0.5、1.0、2.0、5.0、10.0、20.0 mg/kg处理的株高与不施锌比较，在非盐渍条件下分别增加13.60%、13.89%、15.58%、20.84%、21.57%、19.58%，在盐渍条件下分别增加3.31%、8.00%、9.74%、11.51%、8.41%、6.87%。由此认为，绿洲盐化潮土的适宜施锌量为5～10 mg/kg，有害或过量施锌量为≥20 mg/kg。随施锌量的升高，盐渍条件下的土壤有效锌(DTPA-Zn)、碳酸盐结合态锌(CAB-Zn)、松结有机结合态锌(WBO-Zn)、氧化锰结合态锌(OxMn-Zn)、无定形氧化铁结合态锌(AOFe-Zn)、晶形氧化铁结合态锌(COFe-Zn)和残留矿物态锌(RES-Zn)均呈上升趋势，分别增加了15.63%～767.19%、7.69%～296.92%、5.68%～270.45%、0.72%～19.42%、1.82%～65.25%、1.01%～37.61%、0.18%～6.92%。与非盐渍条件下相比，盐渍条件下的玉米株高、干重、含锌量、吸锌量、土壤有效锌(DTPA-Zn)、植物可利用态锌(碳酸盐结合态锌、松结有机结合态锌、氧化锰结合态锌)均降低，其他态锌(无定形氧化铁结合态锌、晶形氧化铁结合态锌和残留矿物态锌)均升高。综合分析认为，施用适量锌肥能显著提高玉米的耐盐性，缓解长期盐分胁迫带来的毒害，在短期内能有效改善土壤-作物系统的锌营养水平。

To reveal the transformation characteristics of exogenous zinc in saline fluvo-aquic soils in Hexi Oasis Areas, pot experiments were conducted to explore the effects of different zinc application amount on the maize seedlings growth and the zinc transformation forms under saline conditions. The results showed that the plant height and dry weight of maize increased at first and then decreased with the increase of zinc application amount under both S0 non-saline and S5 saline conditions and reached the maximum when the zinc application amount was 5 to 10 mg/kg. The maize zinc contents increased with the increase of zinc application, while the zinc uptake amount increased first and then decreased with the increase of zinc application and reached the maximum when the zinc application amount was 10 mg/kg. The plant heights of zinc application under 0.5, 1.0, 2.0, 5.0, 10.0 and 20.0 g/kg treatments were 13.60%, 13.89%, 15.58%, 20.84%, 21.57% and 19.58% higher than CK, no zinc application, respectively under the S0 non-saline condition, and heights were 3.31%, 8.00%, 9.74%, 11.51%, 8.41% and 6.87% higher than CK, respectively under the S5 saline condition. It was concluded that the appropriate zinc application amount in the saline soils were 5 to 10 mg/kg, and the harmful or excessive zinc application amount was ≥20 mg/kg. With the increasing of zinc application, the contents of soil available zinc (DTPA-Zn), carbonate bound zinc (CAB-Zn), loose organic bound zinc (WBO-Zn), manganese oxide bound zinc (OxMn-Zn), amorphous iron oxide bound zinc (AOFe-Zn), crystalline iron oxide bound zinc (COFe-Zn) and residual mineral zinc (RES-Zn) under S5 saline condition showed an upward trend, increasing by 15.63% to 767.19%, 7.69% to 296.92%, 5.68% to 270.45%, 0.72% to 19.42%, 1.82% to 65.25%, 1.01% to 37.61% and 0.18% to 6.92%, respectively. Compared with the S0 non-saline condition, under the S5 saline condition the plant height, dry weight, zinc content, zinc uptake, soil DTPA-Zn, valid zinc(CAB-Zn, WBO-Zn and OxMn-Zn) were decreased, while contents of other zinc(AOFe-Zn, COFe-Zn and RES-Zn) were increased. Comprehensive analysis showed that the application of appropriate zinc fertilizer could significantly improve the salt tolerance of maize, alleviate the toxicity caused by long-term salt stress, and effectively improve the zinc nutrition level of soil-crop system in the short term.

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国家自然科学基金项目(41967016)；甘肃省现代农业科技支撑体系区域创新中心重点科技项目(2021GAAS53)。