Key Laboratory of Natural Disaster and Remote Sensing of Henan Province, Nanyang Normal University, Nanyang 473061, China.
Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Xianyang 712100, China.
Int J Environ Res Public Health. 2022 Dec 6;19(23):16358. doi: 10.3390/ijerph192316358.
Deficiencies of micronutrients in calcareous soils have been reported in different areas of China's Loess Plateau. The objective of this research was to study the influence of the continuous application of micronutrient fertilizers on soil properties and micronutrient availability in this region. The micronutrient fertilizer field plot experiment began in 1984. It included Zn, Mn and Cu fertilizer treatments and the control treatment. The crop system was continuously cropped winter wheat. The soil properties and available Zn, Mn, Cu and Fe were measured. Their relationships were analyzed through correlation and path analysis. After 31 years, the soil pH, CaCO and available P levels decreased; in contrast, the organic matter, fulvic acid, reducing substances and soil moisture levels in the surface soil increased in the micronutrient fertilized treatments compared to the control treatment. Cu and Zn fertilizers promoted the available Cu and Zn levels in the surface and deep soil, but available Mn was not significantly affected by Mn fertilizer. It can be seen from the interaction between the micronutrient availability and micronutrient fertilizers that Zn, Cu and Mn fertilizers can increase the available Fe level; Mn fertilizer can increase the available Cu level, and Cu and Mn fertilizers can increase the available Zn level. This means that Fe, Cu and Zn availability were easy to implement, whereas the soil-available Mn was difficult to improve in calcareous soils on the Loess Plateau. Fulvic acid and organic matter showed a significant and direct effect on the available Zn; the available Mn and Fe were mainly affected by the soil CaCO and moisture; the available Cu was mainly affected by the soil organic matter, available P and reducing substances. These results indicate the importance of organic matter in calcareous soils; it can not only directly affect the availability of micronutrients but also indirectly affect their availability through the indirect interaction with fulvic acid, reducing substances, available P and CaCO. The above conclusions suggest that the long-term micronutrient fertilizers changed some important soil properties and increased the micronutrient availability in the loess-derived soil.
在中国黄土高原的不同地区，人们已经报告了钙质土壤中微量营养素的缺乏。本研究的目的是研究连续施用微量元素肥料对该地区土壤性质和微量元素有效性的影响。微量元素肥料田间试验始于 1984 年。它包括锌、锰和铜肥处理以及对照处理。作物系统连续种植冬小麦。测量了土壤性质和有效锌、锰、铜和铁。通过相关和路径分析分析了它们之间的关系。31 年后，与对照处理相比，施微量元素肥料处理的土壤 pH 值、碳酸钙和有效磷水平降低，而表层土壤的有机质、黄腐酸、还原物质和土壤水分含量增加。Cu 和 Zn 肥料促进了表层和深层土壤中有效 Cu 和 Zn 的含量，但 Mn 肥料对有效 Mn 没有显著影响。从微量元素有效性与微量元素肥料的相互作用可以看出，Zn、Cu 和 Mn 肥料可以提高有效 Fe 水平；Mn 肥料可以提高有效 Cu 水平，Cu 和 Mn 肥料可以提高有效 Zn 水平。这意味着 Fe、Cu 和 Zn 的有效性容易实现，而在黄土高原钙质土壤中，土壤有效 Mn 则难以提高。黄腐酸和有机质对有效 Zn 有显著直接影响；有效 Mn 和 Fe 主要受土壤 CaCO 和水分的影响；有效 Cu 主要受土壤有机质、有效 P 和还原物质的影响。这些结果表明有机质在钙质土壤中的重要性；它不仅可以直接影响微量元素的有效性，还可以通过与黄腐酸、还原物质、有效 P 和 CaCO 的间接相互作用间接影响其有效性。上述结论表明，长期施用微量元素肥料可以改变一些重要的土壤性质，提高黄土衍生土壤中微量元素的有效性。
