Spatial variability of soil phosphorus in grazing systems

2013

Trotter, Mark

Badgery, Warwick

Barron, Joshua

Guppy, Christopher

Haling, Rebecca

Mitchell, David

Millar, Geoff

Editor(s): David L Michalk, Geoffrey D Millar, Warwick B Badgery, Kim M Broadfoot

Conference Publication

en

Publication

NSW Government, Department of Primary Industry

Orange, Australia

une:14359

Phosphorus (P) use efficiency has been identified as a key issue for Australian grazing systems. This project examined the spatial variability in soil P concentration from two separate surveys of grazed pasture fields. A field on the central tablelands of NSW had a range in Bray P of 1.2 to 140 mg/kg and a COV of 107%. The other field on the northern tablelands of NSW reported a range in Colwell P from 13.0 to 121.1 mg/kg and a COV of 59%. Maps of the spatial variability of soil P demonstrated that there is a relationship with field elevation. Application of critical P values to both fields enabled an estimation of the value of site specific fertiliser management. For one field, fertiliser inputs could potentially be isolated to 37% and the other 56% if nutrient additions were targeted at responsive areas. The opportunity for increased fertiliser use efficiency through site specific management (SSM) warrants further investigation. Research is required into both the value of SSM and the techniques that might enable the development of this strategy.

link

Revitalising Grasslands to Sustain our Communities: Proceedings of the 22nd International Grassland Congress, p. 856-859

9781742565439

9781742565422

856

859