IN SITE NET PHOTOSYNTHESIS MEASUREMENT OF A PLANT CANOPY IN A SINGLE-SPAN GREENHOUSE
DOI:
https://doi.org/10.24297/jaa.v7i2.6092Keywords:
CO2 flux, evapotranspiration, on-line monitoringAbstract
Using newly developed sensor units that were more compact and accurate than earlier units (Takakura et al., 2009), this study was conducted to estimate the net photosynthesis of a plant canopy in a practical greenhouse during plant cultivation. Net photosynthesis and the ventilation flow rate are two unknowns in this greenhouse system, with adequate growth of bitter gourd plants. Environmental conditions related to evapotranspiration from the canopy and CO2 flux from the soil surface were measured respectively using the developed sensor units and a box-type CO2 concentration sensor. Heat flux from the soil was also measured. Two equations were solved: one for CO2 balance and one for water vapor balance. On-line monitoring of net photosynthesis is possible using simple and inexpensive sensors, but the obtained data of the canopy photosynthesis were scattered because of frequent changes in the ventilation amount. Furthermore, improved sensor units revealed that the evapotranspiration of the canopy was linearly related to net solar radiation in the greenhouse.
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2. Bontsema, J., Hemming, J., Janssen, H. J. J., Meinen, E., Rispens, S., Steenhuizen, J. W., and de Visser, P. (2011). On-line monitoring van transpiratie en fotosynthese: de praktijk. Rapport GTB-1091, Wageningen UR, 65pp.
3. Miyahira, M., Tamaki, M., Akutsu, M., Usui, T., Okushima, L., Kaiho, A., and Takakura, T. (2015). Calibration device development for spherical solar radiation sensors. J. Adv. Agr., 4, 371-376.
4. Miyahira, M., Usui, T., Kaiho, A., Okushima, L., and Takakura, T. (2014). Lightweight, low-cost, automatic monitoring of global and diffused solar radiation. J. Agr. Met., 70, 133-138.
5. Nederhoff, E. M., Gijzen, H., Veger, J. G., and Rijsdijk, A. A. (1989). Dynamic model for greenhouse crop photosynthesis: Validation by measurements and application for CO2 optimization. Acta Hort., 260, 137-148.
6. Nederhoff, E. M., and Vegter, J. G. (1994). Photosynthesis of stands of tomato, cucumber and sweet pepper measured in greenhouses under various CO2-concentrations. Annals of Botany, 73, 353-361.
7. Takakura, T. (1993). Climate Under Cover. Digital Dynamic Simulation in Plant Bio-Engineering. Kluwer Academic Publishers, 155pp.
8. Takakura, T. (2008). Why Penman–Monteith equation is used yet in the world? Agriculture and Horticulture, 83, 953-957.
9. Takakura, T., Kubota, C., Sase, S., Hayashi, M., Ishii, M., Takayama, K., Nishina, H., Kurata, K., and Giacomelli, G. A. (2009). Measurement of evapotranspiration rate in a single-span greenhouse using the energy-balance equation. Biosystems Engineering, 102, 298-304.
10. Tamaki, M., Usui, T., Inoue, H., Sunagawa, H., and Takakura, T. (2016b). Impact of leaf temperature, vapor pressure deficit, and CO2 concentration on rising photosynthesis rate of Bitter gourd (Shiokaze). ISTHH 2016 International Symposium on Tropical and Temperate Horticulture (Nov. 20-25, 2016), Cairns, Australia.
11. Tamaki, M., Usui, T., Nikawa, T., and Takakura, T. (2016a). Development of a device to measure CO2 concentration in soil and its flux from soil surface. Proc. of Annual Meeting of Agricultural Structures in Kochi, p91-92.
12. Villarreal-Guerrero, F., Kacira, M., Fitz-Rodriguez, E., Kubota, C., Giacomelli, G. A., Linker, R., and Arbel, A. (2012). Comparison of three evapotranspiration models for a greenhouse cooling strategy with natural ventilation and variable high pressure fogging. Scientia Horticulturae, 134, 210-221.
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