Information
The Effect of Ground Cover on Surface Runoff from Experimental Plots & the Effect of Sheet Erosion on Wheat Yield and Quality (Gunnedah)
Level 1 General description
Purpose:
Lang & McCaffrey (1984): To examine the relationship between soil loss and percentage cover on grazing land.
Lang (1979): To examine the relationship between surface runoff and ground cover.
Hamilton (1970): To provide information on the magnitude of production loss of wheat that could be expected as a result of sheet erosion.
Methods (brief)
Hamilton (1970): The study was implemented across five Research Stations within the NSW wheat belt. The study was implemented on 2 blocks within each site and comprised of three treatments:
- Control – no soil removed
- Three inches of surface soil removed
- Six inches of surface soil removed
Three replicates of each treatment were randomized on each of the two blocks. The first block had a wheat-fallow-wheat rotation and the second, a fallow-wheat-fallow rotation.
Lang & McCaffrey (1984): Soil loss data from experimental runoff plots located at Gunnedah Research Centre were analysed in relation to percentage ground cover.
Lang (1979): Runoff was measured from nine 0.01 hectare plots with three treatments of nil, light and heavy grazed plots by sheep.
Jones HR (1961) Runoff and soil loss studies at Wagga Wagga Research Station. Journal of Soil Conservation, New South Wales 17, 156–169.
Edwards K (1987) Runoff and soil loss studies in New South Wales. Technical Report No. 10, Soil Conservation Service of New South Wales.
B. Yu BF Rosewell CJ. 2001. Evaluation of WEPP for runoff and soil loss prediction at Gunnedah, NSW, Australia. Aust. J. Soil Res., 2001, 39, 1131–1145
Key findings (brief)
Lang & McCaffrey (1984):
- Pasture cover was found to affect the frequency and magnitude of erosion, but it appeared to have little or no effect on the relative contribution to total soil loss of individual erosion events.
- Soil loss ranged from 10 kg. ha-1.yr-1 (complete ground cover) to 4 000kg. ha-1.yr-1
- A balance between soil loss and soil formation exists with 50 – 70% vegetative cover.
- Percentage ground cover affected both the frequency and amount of soil loss from the plots, and relatively few major events accounted for most of the soil lost from the plots.
Lang (1979):
- Increased amounts of ground cover resulted in curvilinear decreases in the average frequency of runoff, storm runoff yield, event depth and total average annual runoff.
- 75% ground cover was shown to be critical, above which runoff was slight, below which runoff increased rapidly.
Hamilton (1970):
- The removal of top-soil depressed wheat yields and brought about a decline in wheat quality. When 3 inches of soil was removed wheat yields dropped by 20 to 50% and protein percentage of the grain by 5 to 20%.
Yu and Rosewell (2001)):
- Tested the WEPP model in predicting runoff and erosion for three soil conditions and a ranger of slope lengths.
Location
Gunnedah Soil Conservation Research Centre
Related studies
The Hamilton (1970) study was also carried out on the following Research Stations: Wagga, Cowra, Wellington and Inverell.