Arbuscular mycorrhizal fungus-induced decrease in nitrogen concentration in pore water and nitrogen leaching loss...

Area of Science:

• Soil Science
• Agronomy
• Microbiology

Background:

• Arbuscular mycorrhizal fungi (AMF) are known to influence nutrient cycling in soils.
• The impact of AMF on nitrogen (N) leaching in red soils remains under-investigated.
• Red soils are prevalent in many agricultural regions and susceptible to nutrient loss.

Purpose of the Study:

• To investigate the effect of AMF inoculation on nitrogen leaching in different types of red soils under simulated rainfall.
• To quantify the changes in plant nitrogen uptake and soil nitrogen concentrations due to AMF colonization.
• To determine the correlation between soil nitrogen levels and nitrogen leaching losses.

Main Methods:

• Red soils from wasteland, farmland, and slopeland were used with maize as the host plant.
• A dual-compartment system differentiated between AMF-inoculated (mycorrhizal/hyphal) and non-inoculated (root/soil) treatments.
• Nitrogen concentration in maize, pore water, and leaching losses were measured under simulated heavy rainfall (40 and 80 mm/h).

Main Results:

• AMF inoculation significantly increased maize biomass and nitrogen uptake.
• Nitrogen concentrations in pore water and N leaching losses were reduced by 48-77% and 51-74% respectively in AMF-treated soils.
• Positive correlations were found between pore water N concentration and N leaching losses, with AMF consistently reducing these parameters across soil types.

Conclusions:

• AMF inoculation effectively reduces nitrogen leaching in red soils by enhancing plant nitrogen uptake and decreasing soil pore water nitrogen.
• Rainfall intensity significantly influenced nitrogen dynamics, particularly in farmland soils.
• Management of beneficial microorganisms like AMF presents a viable strategy for sustainable agriculture and nutrient loss reduction.