Work

Phosphate system fertilization in no‐tillage Oxisols: Effects of temporal, horizontal, and vertical distribution of available phosphorus in the soil

Year: 2025

Type: article

Abstract: System fertilization enhances logistics and phosphorus (P) use efficiency, but its effects in high P‐export systems, particularly regarding fertilization timing, placement, and distribution, remain unclear. This study evaluated P fertilization timing (90, 45, and 0 days before winter crop sowing [DBS]), placement (banded vs. broadcast), and spatial distribution (17 × 5 vs. 40 × 10 cm) in subtropical Oxisols with medium and high soil‐test P. Over 4 years, we assessed crop yields, partial phosphorus balance (PPB), and Mehlich‐1 available soil P (0–10 and 10–20 cm) under rotations of corn ( Zea mays L.), soybean ( Glycine max L.), and winter crops including black oat ( Avena strigosa Schreb.), barley ( Hordeum vulgare L.), vetch ( Vicia sativa L.), and fodder radish ( Raphanus sativus L.). Despite pronounced P stratification, yields and PPB were generally unaffected. In medium P soil, the 40 × 10 cm spacing increased P in the 10–20 cm layer to 61% of the critical value after 4 years. In high P soil, P application at winter sowing raised subsurface P to 4.5 mg dm −3 . Soybean yield (5.2 Mg ha −1 ) and PPB (73%) peaked with 90 DBS banded fertilization. Anticipating fertilization by 90 days with 17 × 5 cm spacing improved soybean yield by 20% and PPB by 10% due to better surface P distribution. The 0–10 cm layer remained P‐rich and sufficient for grain yield. However, the benefits of 90 DBS were limited to two seasons. Long‐term studies are needed to refine system fertilization strategies in high‐output grain systems.

Source: Journal of Environmental Quality

DOI: 10.1002/jeq2.70108