Kolby and Angie Jardine's Environmental Science and Adventure Page|
[Most Recent Entries]
Below are the 20 most recent journal entries recorded in
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|Sunday, May 11th, 2014|
|Bidirectional exchange of biogenic volatiles with vegetation
Bidirectional exchange of biogenic volatiles with vegetation: emission sources, reactions, breakdown and deposition.
Link to article
Biogenic volatile organic compound (BVOC) emissions are widely modelled as inputs to atmospheric chemistry simulations. However, BVOC may interact with cellular structures and neighbouring leaves in a complex manner during volatile diffusion from the sites of release to leaf boundary layer and during turbulent transport to the atmospheric boundary layer. Furthermore, recent observations demonstrate that the BVOC emissions are bidirectional, and uptake and deposition of BVOC and their oxidation products are the rule rather than the exception. This review summarizes current knowledge of within-leaf reactions of synthesized volatiles with reactive oxygen species (ROS), uptake, deposition and storage of volatiles, and their oxidation products as driven by adsorption on leaf surface and solubilization and enzymatic detoxification inside leaves. The available evidence indicates that because of the reactions with ROS and enzymatic metabolism, the BVOC gross production rates are much larger than previously thought. The degree to which volatiles react within leaves and can be potentially taken up by vegetation depends upon compound reactivity, physicochemical characteristics, as well as upon their participation in leaf metabolism. We argue that future models should be based upon the concept of bidirectional BVOC exchange and consider modification of BVOC sink/source strengths by within-leaf metabolism and storage.
|Sunday, April 20th, 2014|
|Saturday, October 12th, 2013|
|Tuesday, September 10th, 2013|
|Saturday, September 7th, 2013|
|Plant Cell and Environment article published
Phytogenic biosynthesis and emission of methyl acetate
Acetylation of plant metabolites fundamentally changes their volatility, solubility and activity as semiochemicals. Here we present a new technique termed dynamic 13C-pulse chasing to track the fate of C1–3 carbon atoms of pyruvate into the biosynthesis and emission of methyl acetate (MA) and CO2. 13C-labelling of MA and CO2 branch emissions respond within minutes to changes in 13C-positionally labelled pyruvate solutions fed through the transpiration stream. Strong 13C-labelling of MA emissions occurred only under pyruvate-2-13C and pyruvate-2,3-13C feeding, but not pyruvate-1-13C feeding. In contrast, strong 13CO2 emissions were only observed under pyruvate-1-13C feeding. These results demonstrate that MA (and other volatile and non- volatile metabolites) derive from the C2,3 atoms of pyruvate while the C1 atom undergoes decarboxylation. The latter is a non-mitochondrial source of CO2 in the light generally not considered in studies of CO2 sources and sinks. Within a tropical rainforest mesocosm, we also observed atmospheric concentrations of MA up to 0.6 ppbv that tracked light and temperature conditions. Moreover, signals partially attrib- uted to MA were observed in ambient air within and above a tropical rainforest in the Amazon. Our study highlights the potential importance of acetyl coenzyme A (CoA) biosynthesis as a source of acetate esters and CO2 to the atmosphere.
citation and link to article: Jardine, K., Wegener, F., Ishida, F., Abrell, L., van Haren, J., Werner, C., “Phytogenic Biosynthesis and Emission of Methyl Acetate,” Plant, Cell & Environment, August 13, 2013.
|Friday, September 6th, 2013|
|New publication in: Journal of Experimental Botany
Emissions of putative isoprene oxidation products from mango branches under abiotic stress http://jxb.oxfordjournals.org/content/64/12/3669.1.abstract?keytype=ref&ijkey=UbytJFksydRHSLI
Abstract: Although several per cent of net carbon assimilation can be re-released as isoprene emissions to the atmosphere by many tropical plants, much uncertainty remains regarding its biological significance. In a previous study, we detected emissions of isoprene and its oxidation products methyl vinyl ketone (MVK) and methacrolein (MACR) from tropical plants under high temperature/light stress, suggesting that isoprene is oxidized not only in the atmosphere but also within plants. However, a comprehensive analysis of the suite of isoprene oxidation products in plants has not been performed and production relationships with environmental stress have not been described. In this study, putative isoprene oxidation products from mango (Mangifera indica) branches under abiotic stress were first identified. High temperature/light and freeze–thaw treatments verified direct emissions of the isoprene oxidation products MVK and MACR together with the first observations of 3-methyl furan (3-MF) and 2-methyl-3-buten-2-ol (MBO) as putative novel isoprene oxidation products. Mechanical wounding also stimulated emissions of MVK and MACR. Photosynthesis under 13CO2 resulted in rapid (<30min) labelling of up to five carbon atoms of isoprene, with a similar labelling pattern observed in the putative oxidation products. These observations highlight the need to investigate further the mechanisms of isoprene oxidation within plants under stress and its biological and atmospheric significance. cicicitation:citaCitation: KJardine, et. al J. Exp. Bot. (2013) 64 (12): 3669-3679. doi: 10.1093/jxb/ert202 First published online: July 23, 2013
|Monday, August 19th, 2013|
|Sunday, June 9th, 2013|
There is nothing like the pacific ocean to bring peace and wonder to the heart.
|Tuesday, March 19th, 2013|
|Sunday, March 3rd, 2013|
|fevereiro misto de bay
The set of the Berkeley Rep amazing production of "The Wild Bride"
East and west vantages points of the bay.
The little mangsters cranking out the VOCs
|Saturday, March 2nd, 2013|
Preparing for the little Mangsters experiment.
|Tuesday, February 26th, 2013|
|Sunday, January 20th, 2013|
|The Coastal Trail
Wow!!! Amazing single track, spectacular views of the Pacific Ocean, and crisp, warm winter days. Thank you Coastal Cali!
|Saturday, January 19th, 2013|
|Wednesday, January 16th, 2013|
|temporal and spatial scaling
2012 was an epic year filled with extreme challenges and personal growth. We spent some of the 2012 - 2013 winter break with family, old friends, dancing to cuban jazz, and of course learning and exploring a new place - the Ventana wilderness. This is a place where mountains meet the sea, where in one of the most iconic and populated states in the U.S you'll see no other humans (or puppies) for days and after walking up thousands of feet from the ocean, you find yourself crossing a snow covered serpentine ridge in a vast and beautiful landscape. Catch the 8 minute summary here https://www.dropbox.com/s/m0o3svvfp236dm7/tic%20toc.m4v
|Sunday, December 2nd, 2012|
We give thanks for new experiences with family and friends.
|Thursday, November 15th, 2012|
The Manaus way of life - sharing meals and ideas with great friends and seeing fantastic jungle creatures
|Sunday, November 4th, 2012|