Fig 1.
Study location and field experiment of L. principis-rupprechtii in Hebei Province, China.
Table 1.
Description of sample site used in the experiment.
Fig 2.
Sketch map of the crown divisions.
Upper, Middle and Lower represent three equal divisions of crown depth in the vertical direction.
Fig 3.
Comparison of the measured values and fitted values of net photosynthetic light response curves in different layers on the RHM (a1-a3), NRHM (b1-b3), MRHE (c1-c3) and EM (d1-d3) models.
PAR represents photosynthetic available radiation, MSE represents mean square error, R2 represents the coefficient of determination and AIC represents Akaike information criterion.
Table 2.
Fitting accuracy of different Pn-PAR.
Fig 4.
Comparison of light response parameters of different models at the same layer.
(a) Parameters of (a) the initial quantum efficiency (a). (b) maximum net photosynthetic rate (Pmax). (c) light saturation point (LSP). (d) light compensation point (LCP). (e) dark respiration rate (Rd) for needles at different models. different letters indicate significant difference at p<0.05 level with the least significant difference test, n.s. indicated no significant difference at the level of P<0.05.
Fig 5.
Comparison of light response parameters of different layers at the same model.
(a) Parameters of the initial quantum efficiency (a). (b) maximum net photosynthetic rate (Pmax). (c) light saturation point (LSP). (d) light compensation point(LCP). (e); dark respiration rate (Rd) for needles at different canyon (different letters indicate significant difference at p<0.05 level with the least significant difference test).
Fig 6.
Comparison of light response parameters of different models between south and north direction.
(a) maximum net photosynthetic rate (Pmax); (b) dark respiration rate (Rd); (c) light saturation point (LSP). (d) light compensation point (LCP). (e) the initial quantum efficiency (α). (different letters indicate significant difference at p<0.05 level with the least significant difference test).