Information
Level 2 Detail of experimental conditions (what might be found in a journal paper or project brief in Hydstra)
Description of study
What?
A rainfall simulator study was conducted on cotton hill-furrow systems with a range of ground cover from 0-60% and with or without prior wheel traffic. The first paper of the series evaluated two management practices; retention of surface cover and controlling wheel traffic. The second paper measured pesticide transport in runoff. The third paper measured transport of both nitrogen (N) and phosphorus (P) in runoff.
When and Where?
The study was conducted on an irrigate cotton farm in the Emerald Irrigation Area on 2 separate sites (block 2 and 5), 4km west of Emerald, QLD. Climate at the site is subtropical with summer-dominant rainfall. Soil present is a black Vertosol, Typic Haplustert and is strongly self mulching and strongly crackling. Block 5 simulator site had higher clay and CEC and less silt and fine sand than block 2.
How?
The study was conducted 2-3 weeks after cotton planting in the critical period for erosion. Cotton was grown on 1-m row spacing, planted into the top of hills separated by furrows used for irrigation and wheel traffic. Each 1 m by 12 m plot contained a single, central furrow and its adjoining hills, with 2 plots (a non-wheel track and a wheel track) fitting under the rainfall simulator. At the time of the study the hills were 0.25 m high, with side-slopes of approximately 50. Mean slope along furrows was 1.0% and 1.3% in Blocks 2 and 5, respectively, although furrow slopes on individual rainfall simulator plots varied. Cotton had only recently emerged, giving <5% cover. Surface soil (e.g. 0–50 mm) was loose and at about air-dry moisture content. Subsoil was moist and firm, with no cracks present, having been irrigated before planting.
Silburn and Glanville (2002) measured runoff and sediment movement using a rainfall simulator to apply rain to cotton hill–furrow systems with a range of on-ground covers (0–60%), each with and without prior wheel traffic. Sixteen plots were run; half on non-wheel tracks and half on wheel tracks, across 4 cover treatments.
Silburn et al (2002) took samples of runoff water (~500 mL) for pesticide analysis from each plot 3–4 times, evenly spaced during the runoff hydrograph. These samples were analysed for total concentrations of each pesticide (i.e. total in water and sediment). Immediately after each runoff sample was taken, a portion of runoff was added to a single bottle (per plot), providing a composite (bulked) sample of runoff during the hydrograph.
Silburn and Hunter (2009) took soil samples (0–25 mm) from each plot before rain commenced, from 8 locations on the top of the hills and 8 locations in the bottom of the furrows. These samples were composited for all plots, separately for all hill samples and all furrow samples. These 2 soil samples were air-dried and analysed for a range of soil physical and chemical properties.
Project administration
Site identifier code: N/A
Principal investigator: Silburn DM
Principal data manager: N/A
Principal organizations: Agricultural Production Systems Research Unit, Queensland Department of Natural Resources and Water
Data custodian: Queensland Department of Natural Resources and Water
Key co-operators: N/A
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
- Silburn DM, and Glanville SF. (2002). Management practices for control of runoff losses from cotton furrows under storm rainfall. I. Runoff and sediment on a black Vertosol. Australian Journal of Soil Research 40:1-20.
- Silburn DM, Simpson BW, Hargreaves PA. (2002). Management practices for control of runoff losses from cotton furrows under storm rainfall. II. Transport of pesticides in runoff. Australian Journal of Soil Research 40:21-44.
- Silburn DM, and Hunter HM. (2009). Management practices for control of runoff losses from cotton furrows under storm rainfall. III. Cover and wheel traffic effects on nutrients (N and P) in runoff from a black Vertosol. Australian Journal of Soil Research 47:221-233.
Keywords:
soil erosion, deposition, stubble retention, controlled traffic, cracking clay, sediment size, agricultural chemicals, endosulfan, prometryn, trifluralin, DDE, cover, controlled traffic, water quality, nitrogen, phosphorus, nutrient enrichment ratio.