Seasonal and spatial variations of carbon and water fluxes of rice (Oryza Stiva) from leaf to field scale

Bhone Nay-Htoon1, Xue Wei2, Maren Dubbert1, Jonghan Ko3, Christiane Werner1
1 Department of Agroecosystem Research, BAYCEER, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany
2 Department of Plant Ecology, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany
3 Division of Plant Biotechnology, Chonnam National University, 300 Youngbong‐dong, Buk‐gu , Gwangju, 500‐757, Republic of Korea

P 3.15 in Fluxes between the atmosphere and ecosystems

Poster Session 2 on Tuesday, 16:30-18:00

Agricultural crops play an important role in the global carbon and water cycling process and there is intense research to understand and predict carbon and water fluxes and productivity of cultivated crops under climate change. However, it is particularly challenging to merge information on crops’ ecophysiological and environmental responses at the leaf and plant scale, to the scale of interest for productivity and farmers i.e. field and landscapes scale. However a profound understanding of the carbon and water cycling processes at leaf scale, canopy scale and ecosystem scale and also the drivers of water use at each scales and the linkages and interactions among them are necessary. Thus new methods are requested to scale mechanistical information of crop functioning to larger scales, particularly in complex farming systems. Here we evaluate how information on carbon and water fluxes at the leaf and canopy scale can be assessed at the field scale by remote sensing in an upland rice field.   We asses water use efficiency and the ratio of evaporation to transpiration as the unproductive water flow is an important issue of rice production techniques with environmental implications.

We measured  the carbon and water cycling process of rice in the Chonnam National University research farm Gwangju, Republic of Korea (ROK) throughout the season by leaf and canopy gas exchange of rain-fed and paddy rice treated with three nutrient gradients (50, 115, 180 Kg/ha Nitrogen) along with the remote sensing by Unmanned Aerial Vehicle (UAV).

The preliminary results showed that the main driver of seasonal variation of carbon and water fluxes is the ratio of crop transpiration to evapotranspiration (T/ET). Preliminary results show that canopy development could be monitored efficiently from remote sensing data. A stable T/ET ratio of rice throughout the growing season may improve water use efficient rice production.

Letzte Änderung 04.04.2014