Location: Plant Physiology and Genetics ResearchTitle: Simulation of future global warming scenarios in rice paddies with an open-field ecosystem warming facility Author
|Rehmani, Muhammad Ishaq|
|Ata-ul-karim, Syed Tahir|
Submitted to: Plant Methods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/6/2011
Publication Date: 12/6/2011
Citation: Rehmani, M.A., Zhang, J., Li, G., Ata-Ul-Karim, S., Wang, S., Kimball, B.A., Yan, C., Liu, Z., Ding, Y., 2011. Simulation of future global warming scenarios in rice paddies with an open-field ecosystem warming facility. Plant Methods. 7:41,pp.1-16. Interpretive Summary: In order to study the likely effects of global warming on future rice production, upon which a large fraction of Earth’s population depends for food, a method for applying a heating treatment to open-field plant canopies [i.e., a temperature free-air controlled enhancement (T-FACE) system] is needed which will warm the rice vegetation as expected by the future climate. One approach which has shown promise is infrared heating, which has previously worked well with upland crops such as wheat. However, it had not been tried in flooded paddy fields. This paper describes modifications to the T-FACE system which enabled it to be safely and reliably utilized in rice paddy fields. This research will benefit all consumers of rice and other paddy field crops.
Technical Abstract: Rice (Oryza sativa L.) in Yangtze River Valley (YRV) suffered serious yield losses in 2003 when extreme heatwave (HW), hampered rice reproductive growth phase (RGP). Climate change induced extreme and asymmetrical fluctuations in temperature during heat sensitive stage of rice growth cycle, i.e., RGP have been frequently hampering rice production in YRV. Simulation of HWs produced through feasible open-field warming technique at regional level with distinguished daytime and nighttime temperature increase are required to assess future of crops. Infrared heater (IRH) array (3-meter-diameter) designed by Kimball, is the best available option. Structural modifications in its design are required to operate this technique in paddy fields. After preliminary experiment, we found serious operational constraints, like unstable support for the IRH and potential electricity hazards in standing water. We reduced these problems by cementing the base of supporting bar and carrying cables on the T-shaped hangers and developed Danyang Free-air temperature enhancement (FATE) facility, Danyang, at lower Reaches of YRV. Two IRH-arrays (3-m-diameter), one with 6 IRH (Single Array) and other with 12 IRH (Double Array) were deployed over the rice crop, along with corresponding reference plots with dummy heaters. PID (proportional-integral-derivative) systems with infrared sensors to sense canopy temperatures of the heated and reference plot were used to control IRH output. We were able to achieve temperature very close to our target (+ 3/6 oC, day/night warming) using double array. Single array was not enough to simulate HW warming (ambient+ 3/6 oC, day/night Temperature). Thus, we conclude that Double array can be used to create temperature similar to HW in the paddy fields. Danyang FATE facility will help us understand fate of rice in its oldest niche, YRV.