PMID- 22427372
OWN - NLM
STAT- MEDLINE
DCOM- 20120628
LR  - 20131121
IS  - 1758-4469 (Electronic)
IS  - 0829-318X (Linking)
VI  - 32
IP  - 3
DP  - 2012 Mar
TI  - Use of thermal imaging to determine leaf conductance along a canopy gradient in 
      European beech (Fagus sylvatica).
PG  - 294-302
LID - 10.1093/treephys/tps017 [doi]
AB  - Using an infrared camera, we measured the leaf temperature across different 
      canopy positions of a 23-m-tall deciduous forest tree (Fagus sylvatica L.) 
      including typical sun and shade leaves as well as intermediate leaf forms, which 
      differed significantly in specific leaf area (SLA). We calculated a temperature 
      index (I(G)) and a crop water stress index (CWSI) using the surface temperatures 
      of wet and dry reference leaves. Additional indices were computed using air 
      temperature plus 5  degrees C (I(G) + 5, CWSI + 5) as dry references. The minimum 
      temperature of the wet leaf and the maximum temperature of the dry leaf proved to 
      be most suitable as reference values. We correlated the temperature indices with 
      leaf area-related conductance to water vapor (g(L)) using porometry at the leaf 
      level and using xylem sap flow at the branch level. At the leaf and at the branch 
      level, I(G) and CWSI were equally well suited as proxies of g(L), whereas the 
      relationships of I(G) + 5 and CWSI + 5 with g(L) were only weak or even 
      insignificant. At the leaf level, the correlations of I(G) and CWSI with g(L) 
      were significant in all parts of the crown. The slopes of g(L) vs. I(G) and CWSI 
      did not differ significantly among the crown parts; this indicates that they were 
      not influenced by SLA or irradiance. At the branch level, close correlations 
      (r > 0.8) were found between temperature indices and g(L) across the crown. These 
      results demonstrate that satisfactory relationships between temperature indices 
      and g(L) can be established in tall trees even in those canopy parts that are 
      exposed to relatively low levels of irradiance and exhibit relatively low values 
      of g(L).
FAU - Reinert, Stefan
AU  - Reinert S
AD  - University of Trier, Geobotany, Behringstrasse 21, 54296 Trier, Germany.
FAU - Bogelein, Rebekka
AU  - Bogelein R
FAU - Thomas, Frank M
AU  - Thomas FM
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20120315
PL  - Canada
TA  - Tree Physiol
JT  - Tree physiology
JID - 100955338
RN  - 059QF0KO0R (Water)
SB  - IM
MH  - Dehydration
MH  - Fagus/*physiology/radiation effects
MH  - Germany
MH  - Humidity
MH  - Light
MH  - Plant Leaves/physiology/radiation effects
MH  - Plant Transpiration/*physiology/radiation effects
MH  - Temperature
MH  - Thermography/instrumentation/*methods
MH  - Trees/physiology/radiation effects
MH  - Water/physiology
MH  - Wind
MH  - Xylem/physiology/radiation effects
EDAT- 2012/03/20 06:00
MHDA- 2012/06/29 06:00
CRDT- 2012/03/20 06:00
PHST- 2012/03/20 06:00 [entrez]
PHST- 2012/03/20 06:00 [pubmed]
PHST- 2012/06/29 06:00 [medline]
AID - tps017 [pii]
AID - 10.1093/treephys/tps017 [doi]
PST - ppublish
SO  - Tree Physiol. 2012 Mar;32(3):294-302. doi: 10.1093/treephys/tps017. Epub 2012 Mar 
      15.