Chlorophyll fluorescence Exploratory Region Italy

Usage Rights

This data is Private.

FunDiv intern

Dataset Abstract

Productivity is great in forests with a capacity to intercept incoming radiation and harness its energy efficiently. Thus, understanding the relationships between forest diversity, tree canopy biomass and photosynthetic parameters is central to predicting how diversity will affect a key ecosystem function (i.e., productivity). Specific hypotheses to be tested: I) higher tree species diversity enables greater exploitation of light within forest canopies due to niche partitioning, increasing photosynthesis and primary production (NPP); II) photosynthetic acclimation (ecological resilience to changing environmental factors) on singular species may vary according to the varying ecological conditions, but is supposed to be maintained at plot level in mixed population (interaction of different species-specific behaviors). Photosynthetic acclimation was measured with chlorophyll fluorescence (ChlF), by applying fast and reliable techniques based on the fast kinetics of the chlorophyll fluorescence induction in dark adapted leaves. This method is called JIP-test and is based on the measure of the variable fluorescence at different steps of the fluorescence induction. The measurements were carried out in the 36 plots of the Exploratory Region Italy.

Dataset Design

Chlorophyll fluorescence measurements were replicated on 8 different leaves per tree per two level of crown (top and bottom). The measurements were done on the twigs after the dark adaptation (at minumum four hours in black plastic bag, at ambient temperature).

Spatial Extent

Colline Metallifere, Tuscany (Italy)

Taxonomic Extent

5 tree species (total number sampled tree/specie): Quercus cerris (53), Quercus ilex (56), Quercus petraea (44), Castanea sativa (47), Ostrya carpinifolia (45)

Data Analysis

Data are treated at tree level (for each tree the data are treated for crown level)

Data columns available in the raw data part of this dataset

ID plot
Italy plot number. Unique number ascribed to each plot
Data group: Exploratory plot id
Values
ITA06
ITA03
ITA02
ITA04
ITA05
Mixture level
Mixture level
Data group: Plot descriptor
Values
1
2
4
3
Specie combination
Specie combination
Data group: Tree species code
Values
CS-OC
QC
OC
CS
QC-CS
Specie
Specie
Data group: Tree species
Values
Quercus ilex
Ostrya carpinifolia
Castanea sativa
Quercus cerris
Quercus petraea
ID tree
Number of sampled trees for leaf sampling (isotopic analysis, nitrogen analysis, fluorescence measurements, pathogen and insects)
Data group: Plot descriptor
Values
10
1
11
12
13
Top/Bottom
Two levels of crown sampled. Top (T) are the sunny leaves;bottom (B) is the lower part of the crown, in the shade
Data group: Tree id
Values
B
T
M0
Approximated initial slope (in ms-1) of the fluorescence transient normalized on the maximal variable fluorescence; Datagroup description: Approximated initial slope of the fluorescence transient
Unit: ms-1
Data group: Fluorescence parameters
Keywords: fluorescence, photosynthetic performance
Values
0.29284999999999994
0.29177499999999995
0.2924875
0.30416249999999995
0.2938625
VJ
Variable fluorescence intensity at time 2 millisecond after the onset of the fluorescence induction by saturating light impulse (with intensity > 3000 µmol m-2s-1). It is expressed in arbitrary unit.; Datagroup description: Variable fluorescence at 2 millisecond
Unit: a.u.
Data group: Fluorescence parameters
Keywords: fluorescence, photosynthetic performance
Values
0.286225
0.280225
0.2982
0.290275
0.2946249999999999
VI
Variable fluorescence intensity at time 30 millisecond after the onset of the fluorescence induction by saturating light impulse (with intensity > 3000 µmol m-2s-1). It is expressed in arbitrary unit.; Datagroup description: Variable fluorescence at 30 millisecond
Unit: a.u.
Data group: Fluorescence parameters
Keywords: fluorescence, photosynthetic performance
Values
0.5026999999999999
0.5439666666666667
0.5670125
0.517325
0.563325
FV/FM
Maximum quantum yield of primary photochemistry in dark-adapted state. Expresses the probability that an absorbed photon will be trapped by the PSII reaction centre; Datagroup description: Maximum quantum yield of primary photochemistry in dark-adapted state
Unit: a.u.
Data group: Fluorescence parameters
Keywords: fluorescence, photosynthetic performance
Values
0.7099285714285714
0.6906599999999999
0.7203857142857143
0.720825
0.7147285714285714
Sm
Normalized area above the fluorescence induction curve. It is expressed in arbitrary unit and calculated as SM = Area/ (FM-F0), where F0 is the basl fluorescence intensity, measured at 20 microsecond after the onset of the fluorescence induction by saturating light impulse (with intensity > 3000 µmol m-2s-1).; Datagroup description: Normalized area above the fluorescence induction curve
Unit: a.u.
Data group: Fluorescence parameters
Keywords: fluorescence, photosynthetic performance
Values
17.42502857142857
107.36054999999999
18.1478875
17.167285714285715
115.74461428571428
PIabs
Performance index (potential) for energy conservation from photons absorbed by PSII to the reduction of intersystem electron acceptors; Datagroup description: Performance Index (potential) from photons absorbed
Unit: a.u.
Data group: Fluorescence parameters
Keywords: fluorescence, photosynthetic performance
Values
11.1781875
11.105157142857141
11.29855
11.12095
11.148442857142857
PItot
PItot is the performance index for energy conservation from photons absorbed by PSII to the reduction flux of PSI end acceptors. This parameter is calculated from other parameters of the fluorescence induction curve analysis. It is expressed in arbitrary unit.; Datagroup description: Performance Index total
Unit: a.u.
Data group: Fluorescence parameters
Keywords: fluorescence, photosynthetic performance
Values
10.47222237609172
10.350648987427064
10.374331349494472
10.53487502067796
10.630580440768536