作者: Mark Trotter , Chris Guppy , Rebecca Haling , Tieneke Trotter , Clare Edwards
DOI: 10.1071/CP13449
关键词:
摘要: Nutrient-use efficiency is a key issue for grazing systems in Australia. Spatial variability soil pH and nutrients at the sub-paddock scale may affect of utilisation of, provide an opportunity for, site-specific management (SSM) fertiliser ameliorants. However, there has been little research exploring potential SSM systems. This study examines spatial test pH, phosphorus (P), potassium (K) sulfur (S) two typical pasture fields (a native improved) on Northern Tablelands New South Wales evaluates based comparison with critical values. In both fields, overall paddock mean from grid survey containing >80 samples P, K S (0–10 cm) exceeded values, suggesting that addition or lime was not required. considerable sub-paddock-scale observed, CV ranging 35% to 66% (P, S). The Sprengel–Liebig Law Minimum applied evaluate proportion each field constrained by one more characteristics. Up 55% improved 78% potentially responsive amendments. results this suggest fertilisers ameliorants could substantial improvements productivity possibly reductions use. development application appropriate tools effectively quantify remain challenge, coupled strategies optimise placement amendments account other production limiting factors.