Responses of leaf morphology and PSⅡ chlorophyll fluorescence in leaves of Alhagi sparsifolia growing in soils with varying depths to the groundwater table

Here we report our study of the responses of leaf morphology, pigment content, and chlorophyll fluorescence in A. sparsifolia shrubs growing in soils where the groundwater table is found at 2.5, 4.5 or 11.0 m deep into the soil profile, in a natural arid environment in northwest China. The results showed that at 4.5 m groundwater table depth, leaf area, specific leaf area, and chlorophyll (Chl) b were 22%, 15% and 14% greater than at 2.5 m groundwater table depth, respectively; whereas, leaf thickness was 18% thinner. Additionally, leaf area, leaf thickness, Chl a, Chl b, Chl (a+b), maximum fluorescence yield (Fm), potential activity of PSⅡ (Fv/Fo), and maximum photochemical efficiency of PSⅡ (Fv/Fm) at 11.0 m groundwater table depth were greater by 14%, 15%, 17%, 32%, 21%, 14%, 24% and 9%, respectively, relative to 4.5 m depth to the groundwater table; whereas, specific leaf area was 12% smaller. This research provides a sound theoretical basis to better protect and restore A. sparsifolia in the Cele oasis-desert transitional zone in northwest China.