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 pla...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℃ 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(Ci), and transpiration rate of S. validus that grew under warmed treatment were all significantly higher than those under the control. Gs and Ci of T. orientalis showed similar patterns as S. validus did. For the response curves of Pn to photosynthetic active radiation(P_n-PAR) and intercellular CO_2 concentration(P_n-Ci), S. validus had higher P_n values under elevated temperatures than the control, while Pn-PAR and P_n-Ci 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.展开更多
Aims Quantifying changes in plant growth and interspecific interactions,both of which can alter dominance of plant species,will facilitate explanation and projection of the shifts in species composition and community ...Aims Quantifying changes in plant growth and interspecific interactions,both of which can alter dominance of plant species,will facilitate explanation and projection of the shifts in species composition and community structure in terrestrial biomes expected under global warming.We used an experimental warming treatment to examine the potential influence of global warming on plant growth and interspecific interactions in a temperate steppe in northern China.Materials and methods Six dominant plant species were grown in monoculture and all 15 two-species mixtures for one growing season under ambient and elevated temperatures in the field.Temperature was manipulated with infrared radiators.Important findings Total biomass of all the six plant species was increased by 34–63%in monocultures and 20–76%in mixtures.The magnitude of the warming effect on biomass was modified by plant interactions.Experimental warming changed the hierarchies of both competitive response and competitive effect.The competitive ability(in terms of response and effect)of one C4 grass(Pennisetum centrasiaticum)was suppressed,while the competitive abilities of one C3 forb(Artemisia capillaris)and one C3 grass(Stipa krylovii)were enhanced by experimental warming.The demonstrated alterations in growth and plant interactions may lead to changes in community structure and biodiversity in the temperate steppe in a warmer world in the future.展开更多
基金supported by the National Science Foundation of China (Grant No. 31370497 and 41877346)the Joint Agricultural Projects of Yunnan Province (Grant No. 2017FG001-018)State Forestry Administration Wetlands Conservation Management Center Foundation of China (Grant Nos. 215231 and 215232)
文摘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℃ 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(Ci), and transpiration rate of S. validus that grew under warmed treatment were all significantly higher than those under the control. Gs and Ci of T. orientalis showed similar patterns as S. validus did. For the response curves of Pn to photosynthetic active radiation(P_n-PAR) and intercellular CO_2 concentration(P_n-Ci), S. validus had higher P_n values under elevated temperatures than the control, while Pn-PAR and P_n-Ci 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.
基金supported by the National Natural Science Foundation of China(90511006)Chinese Academy of Sciences(Hundred Talents Program).
文摘Aims Quantifying changes in plant growth and interspecific interactions,both of which can alter dominance of plant species,will facilitate explanation and projection of the shifts in species composition and community structure in terrestrial biomes expected under global warming.We used an experimental warming treatment to examine the potential influence of global warming on plant growth and interspecific interactions in a temperate steppe in northern China.Materials and methods Six dominant plant species were grown in monoculture and all 15 two-species mixtures for one growing season under ambient and elevated temperatures in the field.Temperature was manipulated with infrared radiators.Important findings Total biomass of all the six plant species was increased by 34–63%in monocultures and 20–76%in mixtures.The magnitude of the warming effect on biomass was modified by plant interactions.Experimental warming changed the hierarchies of both competitive response and competitive effect.The competitive ability(in terms of response and effect)of one C4 grass(Pennisetum centrasiaticum)was suppressed,while the competitive abilities of one C3 forb(Artemisia capillaris)and one C3 grass(Stipa krylovii)were enhanced by experimental warming.The demonstrated alterations in growth and plant interactions may lead to changes in community structure and biodiversity in the temperate steppe in a warmer world in the future.
