Using soil surface temperature to assess soil evaporation in a drip irrigated vineyard

• Published in: Agricultural water management 2013-01, Vol.116 (1), p.128-141
• Main Authors: Kerridge, B.L., Hornbuckle, J.W., Christen, E.W., Faulkner, R.D.
• Format: Article
• Language: English
• Subjects: Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agronomy. Soil science and plant productions; Australia; Biological and medical sciences; Drip irrigation; Estimates; Evaporation; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; image analysis; Maxima; microirrigation; soil; Soil (material); Soil evaporation; Soil temperature; Spatial variation; Surface temperature; Temperature sensors; Thermal imaging; Vineyard; Vineyards; water balance; water use efficiency
• ISSN: 0378-3774; 1873-2283
• DOI: 10.1016/j.agwat.2012.07.001

► A soil evaporation method was calibrated for a vineyard in the Murrumbidgee Irrigation Area (Australia). ► Soil evaporation undervine ranged from 0.64mm to 1.83mm. ► Soil evaporation in the inter-row ranged from 0.64mm to 1.45mm. ► Soil evaporation highly variable within field. ► There is potential for this soil evaporation method to be applied under different conditions and crops. Evaporation from the soil is an important part of the water balance of a crop, when considering water use efficiency. In this paper, a non-intensive method is tested to estimate relative soil evaporation, which is based upon a linear function of soil surface temperature change between a saturated and drying soil. The relative evaporation (RE) method of Ben-Asher et al. (1983) was calibrated using microlysimeters and thermal imaging. Soil surface temperature in a drip irrigated vineyard was then collected using infrared temperature sensors mounted on a quad bike, on several days of the 2009–2010 season. Soil surface temperature in the vineyard ranged from 4.6°C to 65.5°C undervine and 6.8°C to 75.6°C in the middle of the row. The difference between daily minima and maxima of soil surface temperature ranged from 20.2°C to 59.7°C in the inter-row and 13.6°C to 36.4°C undervine. Relative evaporation averaged 54% of evaporation from a saturated soil in the inter-row and 97% undervine. Based upon the calculation of RE, the average daily amount of soil evaporation undervine was between 0.64mm and 1.83mm, and between 0.69mm and 2.52mm inter-row. The soil evaporation undervine and inter-row both exhibited spatial variability across the vineyard, however the undervine area had less spatial variability compared to the inter-row area.