Performance of Linear and Nonlinear Two-Leaf Light Use Efficiency Models at Different Temporal Scales

The reliable simulation of gross primary productivity (GPP) at various spatial and temporal scales is of significance to quantifying the net exchange of carbon between terrestrial ecosystems and the atmosphere. This study aimed to verify the ability of a nonlinear two-leaf model (TL-LUEn), a linear two-leaf model (TL-LUE), and a big-leaf light use efficiency model (MOD17) to simulate GPP at half-hourly, daily and 8-day scales using GPP derived from 58 eddy-covariance flux sites in Asia, Europe and North America as benchmarks. Model evaluation showed that the overall performance of TL-LUEn was slightly but not significantly better than TL-LUE at half-hourly and daily scale, while the overall performance of both TL-LUEn and TL-LUE were significantly better (p < 0.0001) than MOD17 at the two temporal scales. The improvement of TL-LUEn over TL-LUE was relatively small in comparison with the improvement of TL-LUE over MOD17. However, the differences between TL-LUEn and MOD17, and TL-LUE and MOD17 became less distinct at the 8-day scale. As for different vegetation types, TL-LUEn and TL-LUE performed better than MOD17 for all vegetation types except crops at the half-hourly scale.

WU Xiaocui;  JU Weimin;  ZHOU Yanlian;  HE Mingzhu;  LAW Beverly;  BLACK Andrew;  MARGOLIS Hank;  CESCATTI Alessandro;  GU Lianhong;  MONTAGNANI Leonardo;  NOORMETS Asko;  GRIFFIS T.;  PILEGAARD K.;  VARLAGIN Andrej;  VALENTINI Riccardo;  BLANKEN P.D.;  WANG Shaoqiang;  WANG Huimin;  HAN Shijie;  YAN Junhua;  LI Yingnian;  ZHOU Bingbing;  LIU Yibo; 

2018-01-16

MDPI AG

JRC100007

2072-4292,   

http://www.mdpi.com/2072-4292/7/3/2238,    https://publications.jrc.ec.europa.eu/repository/handle/JRC100007,   

10.3390/rs70302238,