Information

Loss of phosphorus and nitrogen in runoff and subsurface drainage from high and low input pastures grazed by sheep in southern Australia (Vasey)

Level 1 General description

Purpose:

The purpose of this study was to determine the effect of increased fertiliser and stocking rates on nutrient loss in runoff and subsurface flow from pastures.

 

Site layout

Methods (brief)

Phosphorus (P) and nitrogen (N) concentrations in surface and subsurface flow were measured from 1998 – 2000 in four 0.5 ha hillslope plots. Surface flow volume was measured directly and subsurface water flux was estimated using soil moisture data and a water balance model. A simulated rainfall study was also conducted using 0.6 m2 plots. The treatments represented were: a low P set-stocked sown pasture (SS low P), a high P set-stocked sown pasture (SS high P), a high P sown pasture in a 4-paddock rotation (RG 4-pdk), and an unsown set-stocked pasture (Low P volunteer).

Key findings (brief)

  • Surface runoff is the most important pathway for P losses from perennial pastures in south-western Victoria.
  • The large spatial variation in the volume of runoff across the hillslope site, compared with the smaller variation in runoff TP concentrations between plots indicated that flow volume has a larger influence on P loads than pasture treatment.

 

Various clippings

Location

Vasey (37o24’S, 141o55’E) on the Dundas Tablelands of south-western Victoria.

Key references and sources of this data synthesis

These data summaries have been extracted from:

       i. Melland AR, Mc Caskill MR, White RE and Chapman DF. 2008. Loss of phosphorus and nitrogen in runoff and subsurface drainage from high and low input pastures grazed by sheep in southern Australia. Australian Journal of Soil Research 46: 161 – 172.

Keywords:

Fertiliser, water quality, nutrient loads, soil fertility, hillslope hydrology