Abstract
Recent discoveries of polyhalite (K2SO4.MgSO4.2CaSO(4).2H(2)O) in the UK provide an alternative to conventional fertilizer sources. This work investigated the interaction of polyhalite, commercially known as POLY4, with soil using leaching columns. Different physical forms of polyhalite (powder, crushed rock and granules) were compared to potassium chloride (KCl) for the movement of potassium, calcium, magnesium and sulphur (as sulphate) through the soil profile using 19.7 L of water, equivalent to 4,500 mm rainfall. The nutrients from polyhalite were found to be available at 30 cm depth, with calcium showing signs of interacting with the soil clay particles to release cationic nutrients. Polyhalite granules showed the greatest release of sulphate, magnesium and calcium as a proportion of the additional nutrient with 127%, 71% and 102%, respectively leached. For potassium, all forms of polyhalite had greater release than KCl (powder = 58%; granules = 86%; crushed rock = 57% and KCl 16%). Nutrients from polyhalite and those mobilized from soil interactions are present in soil solution indicating availability for plant growth.
| Original language | English |
|---|---|
| Pages (from-to) | 117-122 |
| Number of pages | 6 |
| Journal | Soil Use and Management |
| Volume | 36 |
| Issue number | 1 |
| Early online date | 17 Oct 2019 |
| DOIs | |
| Publication status | Published - Jan 2020 |
Bibliographical note
The authors wish to thank the analytical team at the University of Aberdeen in supporting the experimental work in the project and Sirius Minerals for providing POLY4, the trademark name of Sirius Mineral's polyhalite products.Keywords
- agriculture
- fertilizer
- nutrient movement
- polyhalite
- potassium
- soil
