Study on Photosynthetic Characteristics,Carbon Fixation and Oxygen Release,Humidification and Cooling of Four Drought-resistant Afforestation Tree Species in Northern China
In order to explore the photosynthetic,transpiration water consumption characteristics and ecological benefits of afforestation tree species in arid and barren mountainous areas of Taihang Mountains,four kinds of seedlings of common drought-resistant afforestation tree species in northern China,Prunus davidiana,Prunus sibirica,Cotinus coggygria and Ulmus pumila,were taken as the research objects.The diurnal changes of net photosynthetic rate,transpiration rate,water use efficiency,stomatal conductance and intercellular CO2 concentration were analyzed by pot simulation,and the ecological benefits of carbon fixation and oxygen release,humidification and cooling were calculated.The results showed as the follow-ing three aspects.(1)The daily mean values of net photosynthetic rate and transpiration rate of Prunus sibirica were the largest,which were significantly different from those of other tree species.The water use efficiency of Prunus davidiana was the best,which was significantly different from other tree species.The intercellular CO2 concentration of Cotinus cog-gygria was the highest,and there was no difference among the four tree species.The order of daily mean value of stomatal conductance was:Prunus davidiana＞Cotinus coggygria＞Ulmus pumila＞Prunus sibirica,and there were significant differences among Prunus davidiana,Ulmus pumila and Prunus sibirica.(2)The net photosynthetic rate of the four tree species was significantly positively correlated with stomatal conductance and transpiration rate.The net photosynthetic rate of Prunus davidiana and Cotinus coggygria was significantly positively correlated with environmental CO2 concentration and atmospheric temperature.There was a significant negative correlation between net photosynthetic rate and atmospheric humidity of Prunus sibirica.(3)The order of daily carbon fixation and oxygen release per unit leaf area was:Prunus da-vidiana＞Ulmus pumila＞Cotinus coggygria＞Prunus sibirica,and there were significant differences between Prunus davidiana and other tree species.The order of humidification and cooling per unit leaf area was:Prunus davidiana＞Cotinus coggygria＞Prunus sibirica＞Ulmus pumila.The differences of daily transpiration,humidification and cooling between Prunus davidiana and other tree species were significant.The comprehensive results showed that the ability of carbon fixation,oxygen release,humidification and cooling of Prunus davidiana was the strongest,followed by Cotinus cog-gygria.The test results could provide a basis for the selection of priority tree species in local ecological construction.
drought-resistant tree speciesphotosynthetic characteristicsecological benefitscarbon fixation and oxygen releasehumidification and cooling
万方数据
维普
