Information
Level 2 Detail of experimental conditions (Capella)
Description of study
What?
A contour bank catchment scale study measured runoff and soil loss from three crop (wheat, sorghum and sunflower) and three residue management practices (conventional, reduced and zero tillage).
When and Where?
From 1982-93 a long term project was established near Capella in the Peak Downs Shire of the central highlands. The soil is a black cracking clay derived from basalt, Vertosol, mollic torrert, 76% clay and is representative of about 70% of the cropping area in the central highlands. The topography of the area is gently undulating; land slope in the experimental area ranged from 1.6 to 2.5%.
Average annual rainfall for the 1982-93 was 535 mm, lower than the long-term average of 588 mm for Capella. Over the experiment, rainfall was lower in summer (October-March) and higher in winter (April-September).
How?
Runoff and soil loss were monitored from 9 catchment areas (contour bays). Catchments were separated by broad-based contour banks. Contour bank spacing ranged between 96 and 161 m, depending on the slope of the land. Contour bank length varied from 725 to 1370 m, with bank gradients between 0.12 and 0.3%. Catchments were 8-17ha.
The experiment had 9 treatments. Sorghum, sunflower, and wheat were grown at the experimental site in 3 crop sequences, S1, S2, and S3. Each crop sequence consisted of zero, reduced and conventional tillage practices, grouped together. The tillage treatments were randomly allocated to the contour bays and maintained in each catchment throughout the study.
Runoff was measured from each catchment as it discharged into a grassed waterway through a 2.4 m parshall flume. Total soil loss from the contour bays was measured by a pumping sampler (Catchment Instrumentation Mk IV), with the sampling arm positioned in the turbulent discharge section of the flume.
Sallaway et al. (1988) used a 35 mm camera attached to a 5 m high boom, operated remotely by time release or extension shutter cable to photograph ground area. Each slide photograph covered a ground area of 2.3 X 1.8 m, equivalent to 4 rows of sorghum and sunflower, and 7 rows of wheat. Six fixed 12 X 12 m sampling areas in each bay were used for agronomic and soil-water measurements, and therefore photographs were taken at the corner locations of these plots.
Between 1983 and 1986, cover measurements were taken in each bay after harvest, after major runoff events, after herbicide applications, before and after most tillage operations, and at planting and anthesis. Stubble weight was estimated using a visual rating by two operators.
Sallaway et al. (1990) analysed field data from the microprocessors to produce hydrographs and hyetographs at 6 min increments, total runoff and rain, peak runoff and maximum 30 min or 15 min rainfall intensity (I30, I15). Runoff events were analysed using multiple-regression analysis.
Project administration
Site identifier code: ROSL
Principal investigator: Carroll C and Sallaway M.M.
Principal data manager: -N/A
Principal organizations: Queensland Department of Primary Industries
Data custodian: Queensland Department of Primary Industries
Key co-operators: National Soil Conservation Program and Grains Research Development Corporation
Data access policy: Research has been published but base data is 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 -N/A
Key references and sources of this data synthesis
These data summaries have been extracted from
- Carroll C, Halpin M, Burger P, Bell K, Sallaway MM, and Yule DF. (1997). The effect of crop type, crop rotation, and tillage practice on runoff and soil loss on a Vertisol in central Queensland. Australian Journal of Soil Research 35: 925-39.
- Carrol C. Hydstra brief – “Springvale” Capella runoff and soil loss (ROSL) study.
- Freebain D, and Cutajar J. (2012). HowLeaky Assessment – Capella Catchment Study.
- Sallaway MM, Lawson D, and Yule DF. (1988). Ground cover during fallow from wheat, sorghum and sunflower stubble under three tillage practices in central Queensland. Soil and Tillage Research 12: 347-364.
- Sallaway MM, Yule DF, Mayer D, and Burger PW. (1990). Effects of surface management on the hydrology of a Vertosol in semi-arid Australia. Soil and Tillage Research15: 227-245.
Keywords:
Runoff, soil loss, tillage practice, ground cover, surface management