Compared with nitrogen fertilizers such as urea and ammonium bicarbonate, coking-grade ammonium sulfate granules have a specific regulating effect on soil due to their sulfate ion (SO₄²⁻) content, and are particularly suitable for the following scenarios:
Alkaline soils (pH > 7.5) often suffer from problems such as "compaction and low nutrient availability". After the ammonium ions (NH₄⁺) in ammonium sulfate are absorbed by crops in the soil, the remaining sulfate ions will combine with alkaline ions (e.g., Na⁺, K⁺) in the soil to form neutral salts, which gradually reduce the soil pH value and alleviate alkaline stress. At the same time, sulfate ions can promote the release of medium and trace elements such as calcium and magnesium in the soil, improving the efficiency of crop nutrient absorption.
Although ammonium sulfate itself is weakly acidic, in acidic soils (pH < 6.0), when applied in combination with organic fertilizers or lime, it can prevent single acidic fertilizers from exacerbating soil acidification. Meanwhile, sulfate ions can supplement sulfur (also an essential medium element for crops) that is easily lost in acidic soils, preventing "sulfur deficiency symptoms" in crops (such as leaf chlorosis and delayed flowering).
After ammonium sulfate granules are applied to the soil, ammonium ions can be adsorbed by soil colloids and are not easily lost with rainwater or irrigation water (with a lower "leaching risk" compared to nitrate nitrogen fertilizers), resulting in a higher nutrient retention rate. This makes them particularly suitable for use in rainy areas or sandy soils (which have poor fertilizer retention capacity), reducing fertilizer waste.
