
TY  - JOUR
A1  - Goh, K. M. 
A1  - Nguyen, M. L. 
T1  - Estimating net annual soil sulfur mineralisation in New Zealand grazed pastures using mass balance models
JF  - Australian Journal of Agricultural Research
JO  - Aust. J.  Agric. Res.
Y1  - 1997
VL  - 48
IS  - 4
SP  - 477
EP  - 484
KW  - soil organic sulfur.
UR  - https://doi.org/10.1071/A95123 
N2  - Estimates of net soil sulfur (S) mineralisation of grazed pastures in New Zealand were made using the New Zealand Ministry of Agriculture (MAF) S model and a recently developed simple mass-balance S model. Quantitative estimates of S inputs and outputs in the MAF S model were also compared with those obtained in recent field trials. Results obtained showed that the MAF S model was reasonably accurate in estimating S inputs and outputs and long-term maintenance pasture S requirements but not short-term pasture S requirements, due to the parameters used not accounting for the effects of major factors affecting soil organic S mineralisation. Net annual soil S mineralisation under high-producing pastures estimated by the simple mass-balance model was substantial, ranging from 17&#183;7 to 29&#183;1 kg S/ha &#183; year, thus showing that the mineralisation of soil organic S can be a significant source of S for pasture plant growth. The inclusion of the MAF soil organic S test into the MAF S model may improve short-term S requirements, but the soil organic S test needs to be calibrated with net soil S mineralisation potential, soil types, management practices, and pasture production. Although some of the excreta S that has been transferred to stock camps may be returned to the main grazing area, this excretal S and sulfate leaching losses were found to be major S outputs of the main grazing area. The results suggested that the mineralisation of soil organic S may not be sufficient to replace S losses indefinitely when S fertiliser applications are withheld. 
ER  -

