Electrokinetic treatment enhances the germination of Chinese cabbage on a treated saline-alkali soil by modifying its physicochemical properties
摘要
Saline-alkali soil has the potential for agricultural productivity, electrokinetic treatment can be used as a development method. In order to explore and verify the complex changes of saline-alkali soil properties under electrokinetic treatment, the study adopted soil agrochemical analysis and a pot experiment. Firstly, the changes in soil pH and electrical conductivity (EC) under different voltage intensities (8, 16, 24, 32 V) and treatment durations (6, 12, 18, 24 h) was investigated. Based on the improvement effects and the movement pattern of the alkaline migration zone, the condition of 32 V for 24 h was selected for further experimentation. Subsequently, the redistribution of soil physicochemical properties after this treatment was evaluated. Furthermore, the feasibility of cultivating Chinese cabbage (Brassica rapa subsp. chinensis) in the treated soil was verified through a pot experiment. Following treatment, the pH in the anode area decreased from 9.10 to 7.24, and the electrical conductivity (EC) reduced from 4.39 to 3.13 dS/m, which makes original moderately saline-alkali soil meets the standard of slightly saline soil in expanded anode area. Significant removal of harmful salt ions was achieved, with reduction rates from 13.83 to 83.45% for Na+ and from 14.14 to 74.74% for Cl−. Sulfate (SO42−) was also removed in localized areas. Conversely, the concentrations of base cations (K+, Ca2+, Mg2+) increased in specific zones. The content of soil organic matter (SOM) locally increased by 14.27% to 66.38%, alkali-hydrolyzed nitrogen (AN) increased by 16.29% to 84.52% and available phosphorus (AP) locally increased by 8.82% to116.46% after electrokinetic treatment. The soil texture in most areas was improved. In the pot experiment, the 7th day germination rate of Chinese cabbage increased to 45% near the treated soil’s anode, compared with untreated group (CK, 0%). However, the treatment also led to the formation and migration of a highly alkaline zone, soil compaction, and sandification, which require management through agronomic measures. The results indicate promise for improving certain soil properties and agricultural potential, while also revealing several problems that need to be solved.