Abstract:
Light-response characteristics of an introduced tree species (
Nyssa aquatic) under the environment of high temperature (35℃) in Three Gorges Reservoir Region was measured by using a Li-6400 portable photosynthesis system in August of 2012. The results showed that net photosynthetic rate,transpiration rate,stomatal conductance and CO
2 use efficiency of
Nyssa aquatic increased firstly,then a little slowed down with photosynthetic active radiation increasing,but light use efficiency decreased with photosynthetic active radiation increasing; The maximum net photosynthetic rate was 6.587 μmol/(m
2·s) and the view of the quantum efficiency was 0.077 mol/mol; Its light compensation point and light saturation point were 16.69 μmol/(m
2·s) and 481.82 μmol/(m
2·s) respectively. It indicated that
Nyssa aquatic had a stronger adaptation for the environment of high temperature in summer in Three Gorges Reservoir Region,and had stronger shade tolerance, so
Nyssa aquatic introduced could better adapt for the ecological environment of Three Gorges Reservoir Region.