Understanding the effects of simulated warming on photosynthetic performance of aquatic plants may provide strong supports for predicting future dynamics of wetland ecosystems in the context of climate change. The plateau wetlands located in Yunnan province are highly sensitive to climate warming due to their high altitude and cold temperature. Here, we conducted a temperaturecontrolled experiment using two temperature manipulations (ambient temperature as the control and 2°C higher than ambient temperature as the warmed treatment) to determine the photosynthetic characteristics of two lakeside dominant species (
Scirpus validus Vahl and
Typha orientalis C. Presl.) in Dianchi Lake. Net photosynthetic rate (P
n), stomatal conductance (G
s), intercellular CO
2 concentration (C
i), and transpiration rate of
S. validus that grew under warmed treatment were all significantly higher than those under the control. G
s and C
i of
T. orientalis showed similar patterns as
S. validus did. For the response curves of P
n to photosynthetic active radiation (Pn-PAR) and intercellular CO
2 concentration (P
n-C
i),
S. validus had higher P
n values under elevated temperatures than the control, while P
n-PAR and P
n-C
i curves of
T. orientalis did not separate clearly under two temperature scenarios. Both
S. validus and
T. orientalis had higher maximum net photosynthetic rate, light saturation point, dark respiration rate, the maximum rate of RuBP carboxylation (V
cmax), maximum electron transport rate driving RuBP regeneration (J
max), the ratio of V
cmax to J
max, triosephosphate utilization, and 1, 5-bishosphate carboxylase ribulose content under warmed treatment than those under the control. This study provides a preliminary step for predicting the future primary production and vegetation dynamics of plateau wetlands in Yunnan province.
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