Fabio Arsego (SARDI), Andrew Ware (SARDI), Helena Oakey (Uni of Adelaide)
|Contributor||SARDI Minnipa Agricultural Centre|
Site 4, Cummins, SA
This research has developed predictive formulas that can be used by growers to estimate in-season soil moisture at different depths and crop nutrient content from proximal sensing (PS) data.
The upper Eyre Peninsula (UEP) is a challenging environment for growers, due to the Mediterranean-type of climate, where irregular and infrequent winter rainfall patterns are coupled with low soil fertility. Additionally, poor soil structure, low water holding capacity and limited nutrient availability provide challenging conditions for plant growth, as growers currently use granular fertilisers which require good soil moisture conditions to enable the uptake of nutrients. Topsoils from calcareous soils may dry quickly after rain events, which may explain poor water use and nutrient extraction efficiency.
Proximal sensing technologies have the potential to support grower’s nutrient management decisions by monitoring in-season soil and crop water and nutrient content (Allen et al. 2017, Arsego et al. 2017). Compared to the Green Seeker/normalised difference in vegetation index (NDVI) device, newer PS technology can use a wider range of wavelengths to predict soil and crop nutritional status in a non-destructive, quick and inexpensive way. Until recently, PS technology was limited to laboratory use given the size and robustness of the machinery necessary to perform the analysis. The development of small, portable PS devices has now allowed the use of this technology in the field, allowing for the potential for PS to be utilised by growers in their paddocks in the near future. In this research, two years of UEP trials have been combined to calibrate PS for crop nutrient content, and one year of data has been examined for soil moisture and nutrient content.
|Lead research organisation||
South Australian Research and Development Institute
|Host research organisation||N/A|
|Trial funding source||GRDC DAS00165|
The present project is part of the bilateral investment initiative between SARDI and GRDC (scope study DAS00165). Special thanks to Douglas Green, Stuart Modra, Ian Burrows, John Montgomerie, Tim Howard, Jake Hull and families for providing the location of field trials. Thank you to Brenton Spriggs, Sue Budarick and Katherina for their collaboration with field activities. Thank you to Sean Mason for reviewing this article.
|Other trial partners||Not specified|
|Sow date||15 May 2018|
|Harvest date||16 November 2018|
|Plot size||5 m x 1.6 m|
|Plot blocking||randomised complete block design|
|Plot randomisation||randomised complete block design|
|Paddock history||2017: Banker canola 2016: Buloke barley 2015: Wyalkatchem wheat|
86 kg/ha Triple Super Phosphate
Boxer gold® 1.5 L/ha, Avadex® 1.5 L/ha, Treflan® 1.7 L/ha, Round up® 2 L/ha, Hammer® 100 ml/ha, Sulphate Ammonia 800 g/ha
|Rainfall avg ann (mm)||423mm|
|Rainfall avg gsr (mm)||314mm|
|Rainfall trial total (mm)||361mm|
|Rainfall trial gsr (mm)||288mm|
SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol 16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.