opti-sciences OS1p, Руководство пользователя

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This is usually not a concern when using ambient sunlight or artificial greenhouse light,
however, clouds and light flecks below a canopy level can cause problems. If one uses a built
in fluorometer actinic illuminator to measure yield, make sure that steady state photosynthesis
has been reached (See the discussion on Yield for more information). Remember that ambient
Sun light contains FAR red illumination for activation of PSI. It is something to consider
when using an internal illuminator for Yield measurements. Far Red illumination is an option
when using internal actinic illumination for yield measurements. See the section regarding an
in depth discussion on quantum photosynthetic yield.
Yield has been found to be more sensitive to more types of plant stress than Fv/Fm, however
one must only compare measurements at the same light level as the value changes at different
light levels. A PAR clip should be used with the fluorometer to measure Yield in all field
applications. This allows for proper comparisons of values and the determination of ETR or
electron transport rate, a parameter that includes both yield and actinic light level. See the
Stress guide for more details.
Light adapted measurements include Yield of PSII or
)
F/Fm’ or Y(II), ETR, PAR (or PPFD),
and Leaf Temp. With RLC (rapid light curves) The OS1p measures ETRmax, lk, and
‘
.
µE – is a micro Einstein . This a dimension that involves both time and area. It is equivalent
to the micro mol. Both terms have been used extensively in biology and radiation
measurements.
µmls - is a micro mole (also abbreviated µmol, or µmol m
-2
s
-1
) . This a dimension that
involves both time and area (per meter squared per second) . It is equivalent to the micro
Einstein. Both terms have been used extensively in biology and radiation measurements.
µmol – or micro mole (also abbreviated µml, or µmol m
-2
s
-1
) . This a dimension that involves
both time and area (per meter squared per second) . It is equivalent to the micro Einstein.
Both terms have been used extensively in biology and radiation measurements.
1µE
PAR – Photosynthetically Active Radiation between 400nm and 700nm. Measured in either
µmols or µE. PAR can be measured in different dimensions such as Watts per meter or in
micro- Einsteins or micro-moles. When using a PAR Clip, dimensions will always be in the
equivalent terms, micro-Einsteins, or micro-moles
PAR Clip – This is a fluorometer accessory that allows the measurement of PAR or PPFD
and Leaf Temperature along with Yield or Y(II) measurements. Since Yield changes with
PAR radiation (or light) levels and temperature levels as well as plant stress, the ability to
record Yield values with these parameters provide control over important variables. A PAR
Clip allows the calculation of relative ETR or Electron Transport Rate. It will also work with
the internal fluorometer actinic illuminator, to measure reproducible and repeatable controlled
values. PAR clips are recommended for field use with quantum photosynthetic yield
measurements. See the section on quantum photosynthetic yield for an in depth discussion.