[Bacillus amyloliquefaciens Biofertilizer Mitigating Soil Ammonia Volatilization]

Area of Science:

• Agricultural Science
• Environmental Microbiology
• Soil Science

Background:

• Ammonia volatilization from farmland soil is a significant environmental issue, leading to air pollution and reduced nitrogen use efficiency.
• Chemical fertilizers, while boosting crop yields, can exacerbate ammonia loss and negatively impact soil microbial communities.
• Biofertilizers offer a potential sustainable alternative for managing soil nitrogen and mitigating environmental pollution.

Purpose of the Study:

• To evaluate the effectiveness of Bacillus amyloliquefaciens biofertilizer (BB) in reducing ammonia volatilization from farmland soil.
• To investigate the impact of BB on crop yield, quality, and soil microbial community structure.
• To elucidate the microbial mechanisms underlying BB's effects on nitrogen cycling.

Main Methods:

• Pot experiments were conducted using four fertilization strategies: no fertilizer (CK), 100% chemical fertilizer (C), 50% BB + 50% chemical fertilizer (B1), and 100% BB (B2).
• Ammonia volatilization flux was measured using the dynamic flow-through chamber method.
• Soil bacterial community composition was analyzed via 16S rDNA high-throughput sequencing during peak ammonia volatilization.

Main Results:

• Ammonia volatilization was reduced by 79.5% in B1 and 84.8% in B2 compared to the chemical fertilizer treatment (C).
• The 100% BB treatment (B2) resulted in the lowest soil nitrate content and the highest crop yield, increasing by 50.5% over CK and 12.3% over C.
• Treatment B1 showed the highest vitamin C content (67.6 mg·kg⁻¹), and BB application enhanced soil bacterial diversity, particularly the abundance of Bacillus and Nitrospira.

Conclusions:

• Bacillus amyloliquefaciens biofertilizer is highly effective in reducing ammonia volatilization in agricultural soils.
• BB application improves crop yield and quality while promoting a healthier soil microbial environment, enhancing nitrogen utilization.
• This biofertilizer presents a sustainable solution for mitigating air pollution and improving agricultural sustainability.