In:
Transactions of the ASABE, American Society of Agricultural and Biological Engineers (ASABE), Vol. 61, No. 4 ( 2018), p. 1231-1239
Abstract:
Abstract. Global mean temperature is likely to rise by more than 2°C by the end of the century and carbon dioxide concentration ([CO 2 ]) is expected to increase from 408 µmol mol -1 in 2018 to 650 µmol mol -1 by 2060-2070. Previous studies and industry experience suggest that there has already been an effect of warmer temperatures on grapevine phenology; harvest dates have advanced and vintages have become shorter over the past 30 years in Australia. In addition, increasing [CO 2 ] in the atmosphere will likely alter grapevine growth, development, and grape quality. Understanding the interactive effects of [CO 2 ] and temperature on grapevines is essential to determine the potential impact of future climate on grape phenology, grape composition, and final wine quality. Open-top chambers (OTC), capable of maintaining air temperature 2°C above ambient throughout the diurnal cycle using an active heating system and fan-assisted air circulation, were established in an experimental vineyard managed to current commercial practice. A system was then developed to elevate atmospheric [CO 2 ] to 650 µmol mol -1 around the grapevines within the OTC. The main engineering goal of the system was to maintain an even temporal and spatial distribution of CO 2 . Monitoring showed that the mean daytime [CO 2 ] at the center of each OTC varied between 620 and 665 µmol mol -1 , maintaining [CO 2 ] at or above 95.4% of the target [CO 2 ] and not exceeding the target by more than 2.3%, meeting the performance criteria of within ±10% of the target concentration. Both the temporal and spatial distributions of [CO 2 ] were more even in heated OTCs than non-heated OTCs. In all heated OTCs, the [CO 2 ] was at or above 90% of the target and within ±10% of the target at all locations assessed (spatial distribution). The mean [CO 2 ] was between 80% and 86% of the target at 40% of locations in OTCs without heating; however, the overall mean [CO 2 ] in the OTCs was 97.5% of the target. The system performed satisfactorily over a wide range of temperatures (20°C to 50°C), with overall standard deviation varying between 85 and 112 µmol mol -1 . This indicates that the CO 2 injection system showed satisfactory performance in controlling [CO 2 ] at the center of each OTC and providing confidence in the results that will be generated from experiments using the system. On average, the heating system maintained a higher temperature (about 2.0°C in both day and night) than the ambient control plots. Keywords: Australia, CO2 injection in grapevines, Elevated CO2, Grapevines, Open-top chamber, Temperature.
Type of Medium:
Online Resource
ISSN:
2151-0040
DOI:
10.13031/trans.12576
Language:
English
Publisher:
American Society of Agricultural and Biological Engineers (ASABE)
Publication Date:
2018
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