论文部分内容阅读
以东北地区常见的园林绿化灌木东北连翘(Forsythia mandshurica)、毛樱桃(Cerasus tomentosa)、小叶丁香(Syringa microphylla)及东北山梅花(Philadelphus schrenkii)为研究对象,于2013年8月使用Li-Cor 6400便携式光合测定系统对其光合蒸腾特性进行了研究,并对净光合速率(Pn)、蒸腾速率(Tr)及其相关生理生态因子进行了相关性分析。结果表明:毛樱桃、小叶丁香的Pn、Tr日变化规律表现为单峰曲线;东北连翘Pn日变化呈单峰曲线,Tr日变化呈双峰曲线,有“午休”现象;东北山梅花Pn的日变化呈双峰曲线,出现“午休”现象,Tr日变化呈单峰型。影响4种灌木的Pn、Tr的主要生理因子是气孔导度(Cond)、胞间CO2浓度(Ci),Pn、Tr与Cond呈极显著正相关(P<0.01),与Ci均呈显著负相关(P<0.05)。光合蒸腾速率与光合有效辐射(PAR)、空气CO2浓度(Ca)、空气相对湿度(RH)等环境因子存在紧密联系,PAR是促进Pn的主要环境因子,而Ca常常成为主要的限制因素。
Forsythia mandshurica, Cerasus tomentosa, Syringa microphylla and Philadelphus schrenkii, a common landscaping shrub in northeastern China, were selected as research objects in August 2013 using Li-Cor The photosynthetic and transpiration characteristics of 6400 portable photosynthesis system were studied, and the correlations of net photosynthetic rate (Pn), transpiration rate (Tr) and their related physiological and ecological factors were analyzed. The results showed that the diurnal changes of Pn and Tr in the pilocarp and the clove leaf were unimodal curve. The diurnal variation of Pn in Forsythia suspensa showed a single peak curve, and the Tr-diurnal variation curve showed a double peak curve with “midday break” The daily change of plum Pn presented a bimodal curve with the phenomenon of “lunch break ”, and the Tr - day change showed a single peak. The main physiological factors affecting Pn and Tr of four shrubs were stomatal conductance (Cond), intercellular CO2 concentration (Ci), Pn, Tr and Cond (P <0.01), and significant negative correlation with Ci Related (P <0.05). The photosynthetic transpiration rate was closely related to environmental factors such as photosynthetically active radiation (PAR), air CO2 concentration (Ca) and air relative humidity (RH). PAR was the main environmental factor to promote Pn, and Ca was often the main limiting factor.