Root anoxia effects on physiology and emissions of volatile organic compounds (VOC) under short-and long-term inundation of trees from Amazonian floodplains

• Published in: SpringerPlus Vol. 1; no. 1; p. 9
• Main Authors: Bracho-Nunez, Araceli, Knothe, Nina Maria, Costa, Wallace R, Maria Astrid, Liberato R, Kleiss, Betina, Rottenberger, Stefanie, Piedade, Maria Teresa Fernandez, Kesselmeier, Jürgen
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 27-07-2012; Springer Nature B.V; BioMed Central Ltd; Springer International Publishing AG
• Subjects: Earth and Environmental Sciences; Hevea; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary); Waterlogging; Igapó; Várzea; Floodplains; Amazonian trees; Volatile Organic Compounds; Short and long-term inundation; Photosynthesis
• ISSN: 2193-1801; 2193-1801
• DOI: 10.1186/2193-1801-1-9

Volatile organic compound (VOC) emissions are affected by a variety of biotic and abiotic factors such as light intensity, temperature, CO
2
and drought. Another stress factor, usually overlooked but very important for the Amazon region, is flooding. We studied the exchange of VOCs in relation to CO
2
exchange and transpiration of 8 common tree species from the Amazonian floodplain forest grown up from seeds using a dynamic enclosure system. Analysis of volatile organics was performed by PTR-MS fast online measurements. Our study confirmed emissions of ethanol and acetaldehyde at the beginning of root anoxia after inundation, especially in less anoxia adapted species such as
Vatairea guianensis
, but not for
Hevea spruceana
probably due to a better adapted metabolism. In contrast to short-term inundation, long-term flooding of the root system did not result in any emission of ethanol or/and acetaldehyde. Emission of other VOCs, such as isoprenoids, acetone, and methanol exhibited distinct behavior related to the origin (igapó or várzea type of floodplain) of the tree species. Also physiological activities exhibited different response patterns for trees from igapó or várzea. In general, isoprenoid emissions increased within the course of some days of short-term flooding. After a long period of waterlogging, VOC emissions decreased considerably, along with photosynthesis, transpiration and stomatal conductance. However, even under long-term testing conditions, two tree species did not show any significant decrease or increase in photosynthesis. In order to understand ecophysiological advantages of the different responses we need field investigations with adult tree species.