We hypothesised that plant P uptake from fluid MAP fertiliser would not be restricted by a soil moisture deficit and also that some of the residual MAP would be available to subsequent crops.
The P fertiliser treatments were: (1) zero P fertiliser applied in Expt 2 or 3; (2) zero P fertiliser applied in Expt 2 and 8 kg P/ha of MAP banded at 40 mm in Expt 3; (3) residual MAP banded at 40 mm in Expt 2 and zero P fertiliser applied in Expt 3; (4) residual MAP banded at 80 mm in Expt 2 and zero P fertiliser applied in Expt 3; (5) residual MAP banded at 40 mm in Expt 2 and 8 kg P/ha of MAP banded at 40 mm before planting in Expt 3.
Uptake was also similar from soil cores with residual MAP fertiliser placed at 80 mm, growing under wet soil moisture conditions.
After Expt 3 (canola), Colwell P values (0-50 mm) of soils containing only residual MAP fertiliser declined sharply.
The resulting residual map will be named the local anomaly map.
With two successive approaches, firstly over the residual map (data minus regional component) and, secondly, over the residual minus previous estimated signal, the successive correlation analysis of the data gave us a distribution of empirical covariances, which were adjusted by means of suitable analytical covariance functions (Fig.