Enhancing phosphorus transformation and microbial activity in acidic soils using K-feldspar: A case study

Area of Science:

• Soil Science
• Environmental Science
• Agronomy

Background:

• Acidic soils immobilize 85-90% of soluble phosphorus (P) with Fe and Al oxides, reducing bioavailability and wasting fertilizer resources.
• Inefficient P utilization in agriculture leads to resource depletion and environmental pollution.
• Developing eco-friendly soil conditioners is crucial for improving P cycling and crop nutrition in challenging soil conditions.

Purpose of the Study:

• To develop and evaluate a novel mineral soil conditioner (MSC) for enhancing phosphorus availability in acidic soils.
• To investigate the effects of MSC on soil P fractions, microbial community diversity, and phosphatase activity.
• To assess the impact of MSC application on crop P content and leaf structure.

Main Methods:

• A mineral soil conditioner (MSC) was formulated using K-feldspar, calcium (Ca), and magnesium (Mg).
• MSC was applied at varying rates (0.25–1.00 ‰) to acidic soil conditions.
• Analyses included available phosphorus (AP), phosphatase activity (ACP, ALP), microbial community profiling (phoC, phoD genes), and Cryo-SEM-EDS for crop leaf analysis.

Main Results:

• MSC application significantly increased soil available phosphorus (AP), including readily available forms (Resin-P, NaHCO3-P).
• MSC enhanced phosphatase activity (ACP and ALP), promoting organic phosphorus mineralization.
• The 1.00 ‰ MSC rate increased the diversity of bacterial communities harboring phoC and phoD genes and improved crop leaf structure and P content.

Conclusions:

• The developed mineral soil conditioner (MSC) effectively improves phosphorus availability and cycling in acidic soils.
• MSC application enhances soil health by increasing microbial activity and facilitating P mineralization.
• MSC demonstrates significant potential as a sustainable soil amendment to improve crop nutrition and reduce P loss in agricultural applications.