Background
Native pasture yields are soil nutrient limited in subtropical regions. The use of powdered rock as a soil amendment is increasing in these regions as it can supply plant nutrients, increasing the yield of pasture in traditional livestock farming systems. Although powdered rock may also be useful to preserve native rangelands, little is known about the nutrient dynamics in rangeland soil–plant systems amended with powdered rock.
Aims
We evaluated the chemical characteristics of an Acrisol and the grassland production treated with different rates of hydrothermalized basalt powder (HBP) to estimate the nutrient transfer from soil to plants in a rangeland.
Methods
Different HBP doses (0, 1, 2, 4, and 8 t ha−1) were applied twice to the native rangeland topsoil, to which soluble fertilizer was never applied. Soil and plant samples were collected and chemically evaluated seven times over 2 years (674 days).
Results
The soil copper (Cu) and potassium (K) contents increased with the HBP dose, while the available phosphorus (P) and potential acidity (H+Al) decreased. The soil pH temporarily increased. The HBP doses did not affect the exchangeable calcium (Ca), magnesium (Mg), or aluminum (Al) contents. The nutrient concentrations in plant dry mass tended to increase for P, K, Ca, and Mg due to the transfer from the soil. The shoot dry mass increased with the HBP dose according to the growth season of the pasture.
Conclusion
These findings suggest that application of HBP improves the soil‐native pasture system by the transfer of nutrients from soil to plants and by increasing dry mass yield. Rock powder application in native pastures (low chemical fertility and acid conditions) is a feasible agronomic alternative for increasing pasture yield with low impact on the system.