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MasterDataSheet_QuantumYield_FASET_Summer2014_SaplingLightCurves

MasterDataSheet_QuantumYield_FASET_Summer2014_SaplingLightCurves_1.csv
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Variables
Plot
  • Label: Plot
  • Definition: Plot ID following AmeriFlux/FASET naming convention
  • Type: Nominal
  • Missing values: None specified
Variables (legacy): 

Subplot

  • Label: Subplot
  • Definition: 5 m radius subplot established on the cardinal axis of plots in FASET
  • Type: Nominal
  • Missing values: None specified

,
Tree Code

  • Label: Tree Code
  • Definition: Assigns unique code to sapling - e.g. F1N_p2.2
  • Type: Code list
  • Codes:
    • The first three characters refer to the subplot where the sapling is found. The letter after the underscore refers to species (p = white pine, o = red oak, m = red maple, b = beech). The number following the letter signifies the number of this species in the plot (the second pine in plot F1N will be labeled "2"). The number following the decimal place (if applicable) refers to the trial number (by default, there was one trial and thus no number after the tree number).
  • Missing values: None specified

,
Species

  • Label: Tree Species
  • Definition: A coded indicator of the tree species associated with the sample. Coding pattern combines the first two letters of the genus and species. For example, Acer Rubrum (red maple) is coded ACRU.
  • Type: Code list
  • Codes:
    • ACRU = Acer rubrum
    • ACSA = Acer saccharum
    • BEPA = Betula papyrifera
    • PIST = Pinus strobus
    • POGR = Populus grandidentata
    • POTR = Populus tremuloides
    • QURU = Quercus rubra
  • Missing values: None specified

,
Dist from plot center

  • Label: Distance from plot center (m)
  • Definition: Distance in meters from the center of the subplot
  • Type: Physical quantity
  • Unit: m
  • Maximum: 5
  • Minimum: 0
  • Precision: 0.1
  • Missing values: None specified

,
Bearing from plot center

  • Label: Bearing from plot center
  • Definition: Bearing from plot center, where N = 0 degrees
  • Type: Physical quantity
  • Unit: degrees
  • Maximum: 350
  • Minimum: 0
  • Precision: 5
  • Missing values: None specified

,
DBH

  • Label: Diameter Breast Height
  • Definition:
  • Type: Physical quantity
  • Unit: mm
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values: None specified

,
Height

  • Label: Total Height
  • Definition: The total height of the tree.
  • Type: Physical quantity
  • Unit: meter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 0.01
  • Missing values:
    • NA =

,
LeafHeight

  • Label: Leaf height
  • Definition: The height above the ground of the leaf being studied.
  • Type: Physical quantity
  • Unit: meter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 0.01
  • Missing values: None specified

,
Date

  • Label: Date
  • Definition: The day on which the sample was taken.
  • Type: Date/time
  • Date format: MM/DD/YYYY
  • Missing values: None specified

,
Time

  • Label: Time
  • Definition:
  • Type: Nominal
  • Missing values: None specified

,
PAR

  • Label: Photosynthetically Active Radiation
  • Definition: Photosynthetically active radiation value. This value can either be an ambient observation or emitted by sampling equipment (e.g., Li-Cor).
  • Type: Physical quantity
  • Unit: micromolesPerMeterSquaredPerSecond
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 1e-06
  • Missing values: None specified

,
Photo

  • Label: Photosynthesis
  • Definition: As measured by the LiCor-6400 Portable Photosynthesis System
  • Type: Nominal
  • Missing values: None specified

,
cond

  • Label: Stomatal Conductance
  • Definition: Rate of passage of a gas, typically carbon dioxide (CO2) or water vapor, entering or exiting the stomata of a leaf.
  • Type: Physical quantity
  • Unit: molesPerMeterSquaredPerSecond
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 1e-05
  • Missing values: None specified

,
Ci

  • Label: Incoming CO2 Concentration
  • Definition: ci = mol CO2 mol air^-1.
  • Type: Nominal
  • Missing values: None specified

,
Tleaf

  • Label: Leaf Temperature
  • Definition:
  • Type: Nominal
  • Missing values: None specified

,
RH_S

  • Label: Relative humidity
  • Definition: Relative humidity of the sample
  • Type: Physical quantity
  • Unit: percent
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 0.01
  • Missing values: None specified

,
Photo correction

  • Label: Photosynthesis correction
  • Definition: Extrapolates photosynthesis rate from leaf area to chamber area
  • Type: Nominal
  • Missing values: None specified

,
Notes

  • Label: Notes
  • Definition: Field notes taken during sampling and processing.
  • Type: Nominal
  • Missing values: None specified

,
Leaf Area

  • Label: Leaf Area
  • Definition: Leaf area measured in cm2 per leaf.
  • Type: Physical quantity
  • Unit: centimeterSquared
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 0.01
  • Missing values: None specified

,
Dry mass

  • Label: Dry mass
  • Definition: Dry mass of the sample.
  • Type: Physical quantity
  • Unit: gram
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 1
  • Missing values: None specified

,
SLA

  • Label: Specific Leaf Area
  • Definition: Specifica leaf area: the ratio of leaf area to dry weight.
  • Type: Physical quantity
  • Unit: centimeterSquaredPerGram
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 0.01
  • Missing values: None specified

,
percent_N

  • Label: Percent Nitrogen
  • Definition: Weight percent nitrogen in the sample.
  • Type: Physical quantity
  • Unit: percent
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 0.001
  • Missing values:
    • NA =

,
percent_C

  • Label: Percent Carbon
  • Definition: Weight percent carbon in the sample.
  • Type: Physical quantity
  • Unit: percent
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: 0.01
  • Missing values:
    • NA =

,
CN_molar_ratio

  • Label: Carbon Nitrogen Molar Ratio
  • Definition: Molar ratio of C:N in the sample of interest. Calculated as follows: C/N = %C / %N * 1.17.
  • Type: Nominal
  • Missing values: None specified

,
Amax

  • Label: Maximum Assimilation
  • Definition: Maximum CO2 assimilation rate, the plateau region of the light response curve
  • Type: Nominal
  • Missing values: None specified

,
a

  • Label: Apparent Quantum Yield
  • Definition: The rate at which a leaf reaches its maximum photosynthetic capacity, the initial slope of a light response curve
  • Type: Nominal
  • Missing values: None specified

,
Vegetative Cover

  • Label: Vegetative Cover
  • Definition: Percent of canopy covered by vegetation (vs. sky)
  • Type: Nominal
  • Missing values: None specified

,
Sky Cover

  • Label: Sky Cover
  • Definition: Percent of canopy covered by sky (i.e. not vegetation)
  • Type: Nominal
  • Missing values: None specified

Methods: 

LIGHT RESPONSE
One of the leaves at the top of the sapling was selected for photosynthesis measurement. Three fascicles from last year's needles were evaluated for Pinus Strobus. We ran the LiCor 6400's LightCurve autoprogram to construct a photosynthesis light response curve for the leaf at 10 irradiance levels (1500, 750, 500, 250, 75, 50, 30, 10, 0 umol photons/m^2/s). We made an effort to stabilize temperature at 24 +/- 1.5 degrees C and humidity between 60 and 70%. The CO2 mixer was set to 380 ppm. Leaves were bagged, labeled and taken to lab for analysis.

LEAF AREA, MASS, N CONTENT
Broadleaf area was evaluated using the LI-3100C Area Meter. Needle area was evaluated by measuring needle widths with a dissecting scope and multiplying by chamber length (3 cm). Samples were then dried, weighed, ground, and submitted for %N/C:N analysis.

VEGETATIVE COVER
Hemispherical photos were taken at the center of each subplot at 1 m height using a 180 degree fisheye lens. CAN-EYE software was used to evaluate vegetative cover using a brightness of 60%.

Additional Information

FieldValue
mimetypetext/csv
filesize244.29 KB
resource typefile upload
timestampOct 04, 2023