Abstract:
We measured the light response curves of
Populus euphratica grown under contrasting experimental groundwater conditions.We assessed the applicability of the light response models for
P.euphratica under different groundwater conditions by comparing fitted photosynthetic characteristic parameters with measured values using four classic models.Results showed that the
LSP,
Pnmax,and
LCP parameters under well-watered conditions were best fit by the modified rectangular hyperbola model,whereas
Rd was better estimated by the non-rectangular hyperbola model.For
P.euphratica under water deficit conditions,the rectangular hyperbola model exhibited better estimation for
R d and
LCP,whereas the modified rectangular hyperbola model was more suitable for estimating
Pnmax and
LSP.Overall,our results suggest that when considering model choice for estimating the light response parameters of
P.euphratica,the modified rectangular hyperbola model and non-rectangular hyperbola model are applicable for plants grown under benign water environments,but the modified rectangular hyperbola model and rectangular hyperbola model are preferable for those under water deficit environments.This study helps clarifying the light response processes of
P.euphratica under different moisture conditions and provides a theoretical basis for photosynthetic characteristics.