不同光合型植物气体交换参数与环境因子的关系

以昆仑山前山低山群自然生长的塔里木沙拐枣(Calligonum roborovskii)和驼绒藜(Ceratoides latens)为研究对象,通过观测分析,探讨了干旱区山地生态系统不同光合型植物气体交换参数特征及其对环境因子的响应,结果如下:①塔里木沙拐枣光合速率、蒸腾速率不同月份变化不明显,对海拔高度升高的响应更积极,驼绒藜光合速率、蒸腾速率呈下降趋势,对海拔高度变化的响应不明显；②两种植物午间光合速率下降归因于叶片光合酶活性下降,气孔调节作用不明显；③塔里木沙拐枣光合速率主要受光合有效辐射强度和温度影响,蒸腾速率与饱和水汽压差负相关性不明显,驼绒藜气体交换参数与环境因子相关性不明显；④水分条件改善是促使塔里木沙拐枣向高海拔迁移的主要因素,温度提高有利于其良好生长。

Relationship between Environmental Factors and Gas Exchange Parameters of Different Photosynthetic Type Plants

To study relationship between plant gas exchange parameters and environmental factors,Ceratoides latens(C3) and Calligonum roborovskii(C4) were taken as the research object.The purpose of our research was as follows:(1) to analyse the diurnal variation characteristics of photosynthesis rate,transpiration rate and stamatol conductance,as well as their responses to altitude elevation,(2) to compartmentalize adjustment types of photosynthetic "noon-break",(3) to detect the seasonal variation of photosynthetic rate and transpiration rate,as well as their response to altitude elevating,and(4) to compare the size order of plant water use efficiency and leaves’ δ13C value.Result showed:(1) The higher the altitude was,the more the photosynthetic rate of Calligonum roborovskii was,monthly variation of photosynthetic rate and transpiration rate of Calligonum roborovskii were not significant,while the response of diurnal and monthly variation of Ceratoides latens to different altitude was not so significant as Calligonum roborovskii;(2) Photosynthetic rate "noon-break" of Calligonum roborovskii and C.latens was caused by assimilation decline of enzyme system,while not by "stamatol limitation factors";(3) Photosynthetic rate and transpiration rate of Calligonum roborovskii were significantly affected by photosynthetic active radiation(PARi) and CO2 concentration,and the association of photosynthetic rate and transpiration rate of Ceratoides latens with environmental factors was not significant;and(4) improvement of water condition was the main factor that promote Calligonum roborovskii migrating to higher altitude,and temperature increase helps the Calligonum roborovskii to grow well.