Gross Primary Production of Rainfed and Irrigated Potato (Solanum tuberosum L.) in the Colombian Andean Region Using Eddy Covariance Technique

Abstract

Potato farming is relevant for global carbon balances and greenhouse emissions, of which gross primary productivity (GPP) is one of the main drivers. In this study, the net carbon ecosystem exchange (NEE) was measured using the Eddy Covariance (EC) method in two potato crops, one of them with an irrigation system, the other under rainfed conditions. Accurate NEE partition into GPP and ecosystem respiration (RECO) was carried out by fitting a light response curve. Direct measurements of dry weight and leaf area were performed from sowing to the end of canopy life cycle and tuber bulking. Agricultural drought in the rainfed crop resulted in limited GPP rate, low leaf area index (LAI), and low canopy carbon assimilation response to the photosynthetically active radiation (PAR). Hence, in this crop, there was lower efficiency in tuber biomass gain and NEE sum indicated net carbon emissions to atmosphere (NEE = 154.7 g C m−2 ± 30.21). In contrast, the irrigated crop showed higher GPP rate and acted as a carbon sink (NEE = −366.6 g C m−2 ± 50.30). Our results show, the environmental and productive benefits of potato crops grown under optimal water supply.

Upscaling gross primary production from leaf to canopy for potato crop (Solanum tuberosum L.)

“…The differentiating element is the treatment of the LAI in each approach. In potato, Martínez-Maldonado et al (2021) demonstrated that the evolution of daily GPP is linked to the behavior of the LAI. Furthermore, it has been shown a direct effect of changes in canopy architecture on simulated productivity (Sprintsin et al 2012).…”

“…The site was located over a fluvio-lacustrine plain with flat landscape, with an average annual temperature ranging from 12 to 14 °C and an annual precipitation from 800 to 1000 mm with bimodal distribution. The June-August and December-February periods are those with the lowest rainfall (Martínez-Maldonado et al 2021), due to the double passage of the Intertropical Convergence Zone (ITCZ). The soils are deep and well drained, with presence of volcanic ash and correspond to Andisol order (Service-USDA 2014).…”

“…The equipment was installed on February 3rd, 2021 (12 days after planting, DAP), and measurements were kept until the end of the canopy life cycle, on June 9, 2021 (138 DAP). EC tower and additional sensor configuration are described by Martínez-Maldonado et al (2021).…”

“…Reco was calculated by subtracting modeled GPP from measured NEE. Data post-processing, quality control, gap-filling, energy balance closure, uncertainty and statistical analysis methods followed the procedures described in Martínez-Maldonado et al (2021).…”

“…Although eddy covariance (EC) measurements provide accurate and reliable information about carbon and energy balances at the ecosystem level, flux measurements are often not available in many places (Ding et al 2014). Therefore, different methodologies are needed to estimate GPP based on extrapolations of chamber and biometric measurements, and canopy upscaling process using readily measurable meteorological and environmental variables (Malhi et al 2009;Wagle et al 2015;Martínez-Maldonado et al 2021).…”