Silicon increases the phosphorus availability of Arctic soils

Area of Science:

• Soil Science
• Geochemistry
• Ecology

Background:

• Phosphorus availability is crucial for plant growth and terrestrial ecosystem productivity.
• Many soils exhibit phosphorus limitation due to phosphorus being bound in unavailable forms, despite high total phosphorus content.
• Silicon's potential to mobilize phosphorus from mineral-bound forms, demonstrated in marine sediments, is less understood in terrestrial soils.

Purpose of the Study:

• To investigate the effect of silicon on phosphorus mobilization in Arctic soils.
• To determine if silicon addition can increase phosphorus availability in phosphorus-limited Arctic soils.
• To explore the relationship between silicon availability and phosphorus mobilization in unmanaged Arctic soils.

Main Methods:

• Analysis of 143 Arctic soil samples with contrasting characteristics.
• Laboratory experiments involving silicon addition to soils.
• Measurement of phosphorus mobilization and soil respiration.

Main Results:

• Silicon availability showed a significant positive correlation with phosphorus mobilization in Arctic soils.
• Laboratory experiments confirmed that silicon addition significantly increased phosphorus mobilization by releasing Fe(II)-P phases.
• Silicon addition also enhanced soil respiration in phosphorus-deficient soils.

Conclusions:

• Silicon plays a key role in regulating phosphorus mobilization in Arctic soils.
• Silicon addition can enhance phosphorus availability by mobilizing mineral-bound phosphorus.
• The findings suggest silicon's importance for sustainable phosphorus management in soils globally.