CHEN Jin1, TANG Yan-hong2, CHEN Xue-hong1, et al. The Review of Estimating Light Use Efficiency through Photochemical Reflectance Index(PRI)[J]. Journal of Remote Sensing, 2008, (2): 331-337. DOI: 10.11834/jrs.20080243.
Net primary productivity(NPP) estimation is an important study field of global change and terrestrial ecosystems(GCTE).Many models used to estimate GPP and NPP have been established
such as CASA、Bio-BGC、BEPS、GLO-PEM
TURC
PSN and so on.Among them
the model based on light use efficiency(LUE) is very popular in estimating GPP and NPP at large scale
because it needs low computation cost
few bio-parameters and easy to be incorporated with remote sensing data.Therefore
estimating LUE accurately is valuable for both the ecological and global change studies.There have been several attempts to model seasonal variation of LUE
mainly as a function of air temperature
water vapour pressure deficit and soil water deficit.However
LUE’s variation with environmental conditions is very complex
it is interrupted by many factors such as air temperature
soil moisture
plant functional type
disease
nutrition condition
light intensity
light component
and so on.The existing models are either too simple to describe or lack reliability.LUE can be estimated directly by remote sensing
and it will be more desirable.A number of studies have revealed that photochemical reflectance index(PRI)
derived from narrow band reflectance at 531 and 570 nm
is related well with LUE in some conditions
which provides possibility in estimating LUE by PRI.Some studies have confirmed this relationship at leaf scale
canopy scale and landscape scale.Meanwhile
many studies have also found that the relationship between PRI and LUE is not robust enough
which is interrupted seriously by many disturbances
such as soil background
species composition
canopy structure
sun zenith
view zenith
atmosphere
and so on.Results from simulation and experiment both revealed that the relationship between PRI and LUE keeps well even under very strict condition
such as high LAI(leaf area index)
single specie and so on.Therefore
it still needs more research for wide application of PRI.This paper reviews the definition of PRI
physiological mechanism leading to the relationship between PRI and LUE
and introduced some case studies to establish the relationship between PRI and LUE through remote sensing.Then some disturbances at leaf scale
canopy scale and landscape scale were analyzed.In the end
a summary about achievements
existing problems and prospective studies are concluded.Although there are still many problems in estimation of LUE through PRI
a few studies have tried to conquer these problems and made some progress.They found that the relationship between PRI and LUE would be more robust by incorporating with other vegetation indices.