scholarly journals Diurnal Variation in Nonstructural Carbohydrate Storage in Trees: Remobilization and Vertical Mixing

2018 ◽  
Vol 178 (4) ◽  
pp. 1602-1613 ◽  
Author(s):  
Aude Tixier ◽  
Jessica Orozco ◽  
Adele Amico Roxas ◽  
J. Mason Earles ◽  
Maciej A. Zwieniecki
2018 ◽  
Vol 221 (3) ◽  
pp. 1466-1477 ◽  
Author(s):  
Morgan E. Furze ◽  
Brett A. Huggett ◽  
Donald M. Aubrecht ◽  
Claire D. Stolz ◽  
Mariah S. Carbone ◽  
...  

2019 ◽  
Vol 39 (7) ◽  
pp. 1109-1120 ◽  
Author(s):  
Erin Wiley ◽  
Carolyn M King ◽  
Simon M Landhäusser

AbstractNonstructural carbohydrate (NSC) remobilization remains poorly understood in trees. In particular, it remains unclear (i) which tissues (e.g., living bark or xylem) and compounds (sugars or starch) in woody plants are the main sources of remobilized carbon, (ii) to what extent these NSC pools can be depleted and (iii) whether initial NSC mass or concentration is a better predictor of regrowth potential following disturbance. To address these questions, we collected root segments from a large mature trembling aspen stand; we then allowed them to resprout (sucker) in the dark and remobilize NSC until all sprouts had died. We found that initial starch mass, not concentration, was the best predictor of subsequent sprout mass. In total, more NSC mass (~4×) was remobilized from the living inner bark than the xylem of the roots. After resprouting, root starch was generally depleted to <0.6% w/w in both tissues. In contrast, a large portion of sugars appear unavailable for remobilization: sugar concentrations were only reduced to 12% w/w in the bark and 2% in the xylem. These findings suggest that in order to test whether plant processes like resprouting are limited by storage we need to (i) measure storage in the living bark, not just the xylem, (ii) consider storage pool size—not just concentration—and (iii) carefully determine which compounds are actually components of the storage pool.


2020 ◽  
Author(s):  
Jinhui Gao

&lt;p&gt;Comprehensive measurements were conducted at the summit of Mount (Mt.) Huang, a rural site located in eastern China during the summer of 2011. They observed that ozone showed pronounced diurnal variations with high concentrations at night and low values during daytime. The Weather Research and Forecasting with Chemistry (WRF-Chem) model was applied to simulate the ozone concentrations at Mt. Huang in June 2011. With processes analysis and online ozone tagging method we coupled into the model system, the causes of this diurnal pattern and the contributions from different source regions were investigated. Our results showed that boundary layer diurnal cycle played an important role in driving the ozone diurnal variation. Further analysis showed that the negative contribution of vertical mixing was significant, resulting in the ozone decrease during the daytime. In contrast, ozone increased at night owing to the significant positive contribution of advection. This shifting of major factor between vertical mixing and advection formed this diurnal variation. Ozone source apportionment results indicated that approximately half was provided by inflow effect of ozone from outside the model domain (O&lt;sub&gt;3-INFLOW&lt;/sub&gt;) and the other half was formed by ozone precursors (O&lt;sub&gt;3-PBL&lt;/sub&gt;) emitted in eastern, central, and southern China. In the O&lt;sub&gt;3-PBL&lt;/sub&gt;, 3.0% of the ozone was from Mt. Huang reflecting the small local contribution (O&lt;sub&gt;3-LOC&lt;/sub&gt;) and the non-local contributions (O&lt;sub&gt;3-NLOC&lt;/sub&gt;) accounted for 41.6%, in which ozone from the southerly regions contributed significantly, for example, 9.9% of the ozone originating from Jiangxi, representing the highest geographical contributor. Because the origin and variation of O&lt;sub&gt;3-NLOC&lt;/sub&gt; was highly related to the diurnal movements in boundary layer, the similar diurnal patterns between O&lt;sub&gt;3-NLOC&lt;/sub&gt; and total ozone both indicated the direct influence of O&lt;sub&gt;3-NLOC&lt;/sub&gt; and the importance of boundary layer diurnal variations in the formation of such distinct diurnal ozone variations at Mt. Huang.&lt;/p&gt;


2021 ◽  
Author(s):  
Morgan E. Furze ◽  
Dylan K. Wainwright ◽  
Brett A. Huggett ◽  
Thorsten Knipfer ◽  
Andrew J. McElrone ◽  
...  

2012 ◽  
Vol 5 (11) ◽  
pp. 2601-2611 ◽  
Author(s):  
T. Kuwahara ◽  
T. Nagahama ◽  
H. Maezawa ◽  
Y. Kojima ◽  
H. Yamamoto ◽  
...  

Abstract. We have performed ground-based measurements of stratospheric chlorine monoxide (ClO) during the summer in 2009 over the Atacama highland, Chile, a new observing site in the mid-latitude region in the Southern Hemisphere, by using a millimeter-wave spectroscopic radiometer. The radiometer, equipped with a superconducting receiver and a digital Fourier spectrometer, was developed by Nagoya University, and the new observing system provides us high sensitivity and stable performance to measure the very weak ClO lines. The receiver noise temperature of the superconducting receiver is 170 K in DSB. To reveal the diurnal variation of ClO, we retrieved the vertical mixing ratio profiles by the weighted-damped least-squares algorithm applied for the spectral data at 203 GHz obtained between 5 and 16 December 2009. The total error on the retrieval is estimated to be 20% to 30% in an altitude range from 40 km to 50 km. The amplitude of the diurnal variation is estimated as 33% of the daytime average at 40 km. The observed time variation shows a pattern similar to that of the previous works observed in the northern mid-latitude region.


2012 ◽  
Vol 5 (1) ◽  
pp. 1907-1945
Author(s):  
T. Kuwahara ◽  
T. Nagahama ◽  
H. Maezawa ◽  
Y. Kojima ◽  
H. Yamamoto ◽  
...  

Abstract. We have performed ground-based measurements of stratospheric chlorine monoxide (ClO) during the summer in 2009 over the Atacama highland, Chile, a new observing site in the mid-latitude region in the Southern Hemisphere by using a millimeter-wave spectroscopic radiometer. The radiometer equipped with a superconducting receiver and a digital Fourier spectrometer is developed by Nagoya University, and the new system provides us high sensitivity and stable performance to measure the very weak ClO lines. The receiver noise temperature of the superconducting receiver is 170 K in DSB. To reveal the diurnal variation of ClO, we retrieved the vertical mixing ratio profiles by the weighted-damped least squares algorithm applied for the spectral data at 203 GHz obtained between 5 and 16 December 2009. The total error on the retrieval is estimated to be 20% to 30% in an altitude range from 40 to 50 km. The amplitude of the diurnal variation is &amp;pm;33, &amp;pm;33, and &amp;pm;36% at 40, 45, and 50 km, respectively. The time variation curve is basically similar to the previous diurnal variation observed in the northern mid-latitude region but there is a tendency that the increasing rate after the sunrise becomes smaller as the altitude increases.


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