浑善达克沙地人工牧草蒸腾光合作用与环境因子的关系分析

Analysis of Relationships between Photosynthetic and Transpiration Rates of the Forage Grass with Environmental Factors in Otinday Sandy Area

以浑善达克沙地人工种植的老芒麦、披碱草、蒙古冰草及紫花苜蓿为典型牧草,选择光合有效辐射、空气温度、空气湿度和二氧化碳浓度为主要环境影响因子,利用相关分析、偏相关分析、通径分析及决策系数等方法从不同角度系统地分析了人工牧草蒸腾作用和光合作用的环境影响,结果表明,人工牧草的光合作用和蒸腾作用主要受到光合有效辐射的影响,其次才是其他环境要素不同程度的直接影响和间接影响,因此,建立人工牧草蒸腾速率和光合速率的环境因子响应模型和计算人工牧草需水量应充分考虑光合有效辐射的作用。

In this paper,Elymus,Leymus,Agropyron and Medicago in the Otinday Sandy area are selected as the typical forage grass to analyze the relationships between photosynthetic and transpiration rates of the forage grass with environmental factors.The environmental factors include photosynthetic active radiation,air temperature,air humidity and carbon dioxide concentration.By correlation analysis,partial correlation analysis,path analysis and calculated decision coefficient,the relationships between photosynthetic and transpiration rates of the forage grass with environmental factors are presented in different degree.The results show that the photosynthesis and transpiration of the forage grass are affected mainly by the photosynthetic active radiation,then from the direct and indirect effects in different levels of the other environmental factors.So,the photosynthetic active radiation should be fully considered when the transpiration rate and photosynthetic rate or water requirements of the forage grass are calculated by environmental factors model.