Humic acid application improves soil quality and wheat yield in saline-alkali soils

Area of Science:

• Soil Science
• Agronomy
• Environmental Science

Background:

• Humic acid (HA) is a key soil conditioner for saline-alkali soil remediation.
• Its specific impacts on soil quality, crop yield, and underlying mechanisms require further investigation.

Purpose of the Study:

• To investigate the effects of varying humic acid application rates on soil properties, microbial communities, and wheat growth in saline-alkali soils.
• To determine the optimal humic acid rate for improving soil quality and wheat productivity.

Main Methods:

• A field experiment was conducted over one year using four humic acid application rates (0, 3, 7.5, and 15 Mg ha^-1).
• Soil samples were analyzed for chemical properties, organic matter, microbial abundance (Ascomycota), and soil quality index.
• Wheat growth parameters, including root biomass, length, volume, and plant growth index, were measured.

Main Results:

• Humic acid application significantly increased soil available potassium, phosphorus, and organic matter while decreasing pH, electrical conductivity, chloride, and sulfate ions.
• Soil microbial communities, particularly Ascomycota, were enhanced in the rhizosphere.
• Wheat root development and plant growth index improved, showing a positive correlation with soil quality and yield.

Conclusions:

• Humic acid application effectively improves saline-alkali soil quality and promotes wheat growth and yield.
• The application rate of 7.5 Mg ha^-1 (HA7.5) is recommended as the optimal rate for balancing cost-effectiveness and benefits.
• Humic acid shows significant potential for saline-alkali soil remediation and agricultural productivity enhancement.