Photosynthetic Capacity Measurements of Lonchocarpus capassa using Licor 6400, Kruger National Park, South Africa, 11-03-2009StevenHigginsDepartment of Physical Geography, Goethe University Frankfurt am MainAltenhoeferallee 1Frankfurt am MainHesse60438GermanyFor photosynthetic capacity we used a Licor 6400 to derive A-Ci curves (curves of the response of
photosynthetic rate to changes in leaf internal CO2 concentration) following the field protocol used by
Xu and Baldocchi (2003). This protocol involves allowing the leaf to acclimatise for 30 minutes to a
high (1000 ppm) chamber CO2 concentration and then programing a decrease in CO2 concentration in the
sequence 1000, 700, 500, 360, 200, 150, 100, 50 ppm. The leaves were given eight minutes
to acclimatise to each CO2 level before measuring the gas exchange parameters. Light intensity
was set to 800 mymol*m2*s-1. licor 6400 measurements photosynthetic capacity plant growth savannalonchocarpus capassaKruger National Park, South Africa31.4831.48-24.01-24.012009-03-12GenusLonchocarpusSpeciescapassaStevenHigginsDepartment of Physical Geography, Goethe University Frankfurt am MainAltenhoeferallee 1Frankfurt am MainHesse60438Germanyhiggins@em.uni-frankfurt.de excl-11-03-09-lc excl-11-03-09-lc1977 13#x0Acolumn #x09 ecogrid://knb/shiggins.180.1 publicread "Obs"Observation number natural "HHMMSS"Clock time string, 24 hour HH:MM:SS "FTime"Number of seconds that has elapsed since file was opened. second real"Photo"
Photosynthetic rate
mymol CO2 m-2 s-1
real
"Cond"Conductance to H2O mol H2O m-2 s-1 real"Ci"
Intercellular CO2 concentration
mymol CO2 mol-1
real
"Trmmol"Transpiration rate mmol H2O m-2 s-1 real "VpdL"Vapor pressure deficit based on Leaf temp (kPa) kilopascal real "Area"Leaf area (cm2) squareCentimeters natural "StmRat"Stomatal ratio estimate dimensionless natural "BLCond"Total Boundary Layer Conductance mol m-2 s-1 real "Tair"Temperature in sample cell (C) celsius real "Tleaf"Temperature of leaf thermocouple (C) celsius real "TBlk"IRGA Block Temperature (C) celsius real"CO2R"
Reference cell CO2
mymol CO2 mol-1
real
"CO2S"
Sample cell CO2
mymol CO2 mol-1
real
"H2OR"Reference cell H2O mmol H2O mol-1 real "H2OS"Sample cell H2O mmol H2O mol-1 real "RH_R"Relative humidity in the reference cell (%) number real "RH_S"Relative humidity in the sample cell (%) number real"Flow"
Flow rate to the sample cell
mymol s-1
real
"PARi"
In-chamber quantum sensor
mymol m-2 s-1
natural
"PARo"
External PAR
mymol m-2 s-1
natural
"Press"Pressure (kPa) kilopascal real"CsMch"
Sample CO2 offset
mymol mol-1
real
"HsMch"Sample H2O offset mmol mol-1 real "StableF"Stable / Total as fraction number real "Status"Status variable dimensionless natural21attached_fileNot authorized to access resourceOtherattached_fileNot authorized to access resourceOther mymol CO2 m-2 s-1 mol H2O m-2 s-1 mymol CO2 mol-1 mmol H2O m-2 s-1 mol m-2 s-1 ÃÂümol s-1mymol s-1 mymol m-2 s-1 mymol mol-1 mmol mol-1 mmol H2O mol-1