Information
Level 2 Detail of experimental conditions (what might be found in a journal paper or project brief in Hydstra)
Description of study
What?
Adamson (1974) monitored two catchments for runoff and soil loss under differing soil conservation measures.
Adamson (1978) looked at the relationship between rainfall erosivity and soil loss under varied crop rotations over a long-term study.
Hamilton (1970) conducted a comparative study of the quantitative depressions in wheat yield and quality that results from sheet erosion at five Soil Conservation Research Stations over fourteen years (1955 – 1968). Data analysed for each Research Station was obtained over different time periods.
When and Where?
Adamson (1974)
The study commenced in 1951 at the Wagga Research station. The site is subject to hot dry summers and cool wet winters. During summer, evapotranspiration exceeds rainfall and the duration of runoff from storms is generally only a few hours. During winter however, rainfall generally exceeds evapotranspiration and flow duration may be for several days.
The soil in both catchments is a yellow solodic and is classified as Dy2.42. Deepest soils occur on the lower slopes and rock outcrops are common on the ridges. A typical soil profile comprises a hard-setting A horizon of dull orange fine sandy loam overlying a coarse angular-blocky B horizon of yellow brown light clay.
Catchment details can be viewed in Table 2.
Adamson (1978)
The study commenced in 1948 and concluded in 1970 at the Wagga Research Centre. Figure 1 details annual and erosive rainfall data.
How?
Adamson (1974)
Two catchment areas of similar size and topography were identified in the wagga research station. One catchment was left untreated (the control). The untreated catchment was moderately sheet eroded and contained an active erosion gully. No fertilizer was applied and the stocking rate was maintained to ensure the pasture was as short as possible. The principle source of sediment (gully) was located centrally.
Prior to the commencement of the study the treated catchment was severely sheet eroded and several gullies were present. The gullies were filled with soil and contour furrows were laid out at 1m vertical intervals. Improved pastures of Lolium rigidum and Trifolium subterraneum were established at the site. The site was aerially top-dressed annually with 125 kg/ha of superphosphate and was stocked to maintain good cover at all times. Depression storage within the contour furrows was estimated at 40 mm.
Two rainguages were installed within the catchments to monitor rainfall depth. Three rainguages outside of the catchments were also installed to provide further measurements. A pluviometer was installed within the untreated catchment. Runoff was measured from each catchment by a H flume equipped with water stage recorders. Sediment losses were monitored by a Coshocton-type sediment sampling wheel mounted below each flume. Regression analysis was used on the data to derive linear relationships.
Adamson (1978)
Runoff plots were implemented at the Wagga Research Centre. Runoff and soil loss were measured from plots 41.5 metres long on an 8% slope under different crop rotations. The rotation involved a long fallow which normally began in October.
Hamilton (1970)
Two blocks were implemented on the site, one comprised of a wheat-fallow-wheat rotation and the other comprised of a fallow-wheat-fallow rotation. Three replicates of each treatment were randomized on each of the blocks. The treatments were as follows:
- Control – no soil removed
- Three inches of surface soil removed
- Six inches of surface soil removed
Each plot had a furrow dug along the entire length of the lower side to provide drainage and prevent run-off washing from plot to plot. Each plot had a harvested area of one hundredth of an acre or six rows of a combine for the required length.
Normal cultural practices were carried out throughout the experiment. Manual harvesting was completed and the seed was then threshed, cleaned and weighed. Samples were also tested for nitrogen determinations using the Kjeldahl method.
Project administration
Site identifier code: N/A
Principal investigator: Adamson CM and Hamilton GJ
Principal data manager: N/A
Principal organizations: Wagga Research Station, Soil Conservation Service of NSW
Data custodian: Wagga Research Station
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:
- Adamson CM. (1974). Effects of soil conservation treatment on runoff and sediment loss from a catchment in southwestern New South Wales, Australia.
- Adamson CM. (1978). Conventional tillage systems as they affect soil erosion – in southern New South Wales.
- Hamilton GJ. (1970). The effect of sheet erosion on wheat yield and quality. Soil Conservation Journal. April pp. 118 – 123.
Keywords:
Soil conservation, pasture, runoff, erosion, soil loss, conventional tillage, sheet erosion, wheat yield, NSW wheat belt