Information
Nutrient Balances and Transport from Agricultural and Rainforest Lands: a case study in the Johnstone River Catchment
Level 1 General description
Purpose:
The objective of the project was to determine fertiliser application efficiencies from field nutrient balances under "conventional" and "best bet" management practices for sugarcane, bananas, dairy pasture and rainforest.
Methods (brief)
Nitrogen quantities were measured from fertiliser and rainfall input, runoff and leaching losses and crop uptake. The mineralisation or immobilisation of nitrogen was measured by the change in soil mineral nitrogen status and the change in the easily mineralisable nitrogen between planting or harvesting and the following harvesting of each crop.
The sites were installed with flumes, automatic runoff samples, lysimeters and automatic weather stations to enable the measurement of all hydrologic components. Soil and plant sampling allowed a balance to be developed at each site for nitrogen and phosphorus.
Key findings (brief)
From a catchment prospective the most significant finding during the study period was that the concentrations of nutrients and sediment in runoff water were low and that other loss processes were more significant.
Location
All sites were located on Ferrosols of the Johnson River catchment and were comprised of conventional and best bet management practices for sugarcane, bananas and dairy pastures with a rainforest site instrumented for base line nutrient data collection.
Related studies
N/A