Information
Level 2 Detail of experimental conditions (what might be found in a journal paper or project brief in Hydrstra)
Description of the Study
What?
The study measured water quality (nutrients and herbicides) in runoff from CTF and CP, during simulated and natural rainfall events.
When and Where?
This productivity trial was situated on a 5.13 ha block with 0.25% slope and was planted with the sugarcane variety Q135 on 30th July 2002. The monitoring study occurred from 2006-2007 (1 year study).
The soil across the paddock can be generally described as 0.3 m deep, dark to very dark brown (sometimes greyish) heavy clay loam with a fine sandy A horizon; there is a sharp change to a dark to yellowish or greyish brown medium clay B horizon with a strongly prismatic structure.
How?
The aim was to assess the runoff and water quality of two farming systems (row/bed/traffic treatments) (Figure 1, Table 1) including:
(1) Current practice (CP) with 1.5 m wide beds and a single row of sugarcane in the centre of the bed
(2) Controlled traffic farming (CTF) with dual sugarcane rows (0.8 m apart) in permanent 2 m beds
Both were no-till green harvested and had 90-100% cover
Each system was treated with two different nitrogenous fertilisers and methods of residual herbicide application. These were paired as:
(1) Surface application of Liquid One Shot (dunder) and broadcast application (100% coverage) of residual herbicides,
(2) Sub-surface split stool application of Nitra King S (granular) and banded application (50-60% coverage) of residual herbicides (on the centre of bed only).
Artificial rainfall stimulation was undertaken on three different management practices. The rainfall simulator consists of a mobile six piece modular A-frame. Runoff, as well as sediment, nutrient and herbicide concentrations were determined for each set of simulations. Rain was applied at 100 mm/hr until 40 minutes of runoff was generated. The runoff rate was measured manually at the simulator plot outlet, every 4 minutes (2 minutes at initial and tail flows). Discrete samples for total sediment (includes suspended sediment, bedload and organic matter i.e. cane trash), herbicides and nutrients (total and filtered) were collected every 8 minutes (4 minutes on tail flows).
The paddock-scale study involved the installation of two flumes and automatic samplers to collect runoff from natural rainfall to complement plot-scale trials. Flood-event samples were also collected during the 2006/07 wet season 16 km downstream of the field site from Sandy Creek.
The study also incorporated a comparison with a catchment scale measurement conducted in the Sandy Creek.
Project administration
Site identifier code: N/A
Principle investigator: B Masters
Principle data manager: N/A
Principle organisations: Department of Natural Resources and Water, Mackay, Mackay Whitsunday Natural Resource Management Group, Mackay
Key co-operators: Gerry Deguara
Data access policy: Research has been published by base data not archived
Planned pathway for data: Completed study, no evidence of formal database records
Data warehousing: for ongoing studies – N/A
Planned data upload frequency for ongoing studies: for ongoing studies – N/A
Key references and sources of this data synthesis
These data summaries have been extracted from:
Masters B, Rohde K, Gurner N, Higham, W and Drewry J. (2008). Sediment, nutrient and herbicide runoff from cane farming practices in the Mackay Whitsunday region: a field-based rainfall simulation study of management practices, Queensland Department of Natural Resource and Water for the Mackay Whitsunday Natural Management Group, Australia.
Keywords:
hydrology, water quality, sugar cane, Mackay Whitsundays