黄土半干旱区侧柏蒸腾作用及其与环境因子的关系

Relationship between transpiration of Platycladus orientalis and environmental factors in semi-arid region on Loess Plateau.

利用Li 160 0稳态气孔仪,对黄土半干旱区山西省方山县试验地侧柏的蒸腾作用及其环境因子进行测定.该研究的目的是为分析该地区侧柏蒸腾作用对环境因子的响应和侧柏最适的水分生态条件提供理论依据.结果表明:蒸腾速率日变化曲线呈双峰型,蒸腾速率与土壤含水量的关系呈三次曲线相关,蒸腾速率与气孔阻力的关系呈幂函数相关.蒸腾作用受环境因子综合作用的影响。

The transpiration rate, stomatal resistance and environmental factors of Platycladus orientalis in the test field of Fangshan Country of Shanxi Province in the semi-arid region of the Loess Plateau were measured with a portable steady porometer (Li-1600). The study provides theoretical basis in analyzing the transpiration response on the environmental factors and the optimum water ecological condition of Platycladus orientalis in semi-arid region. The results show that the diurnal course of transpiration rate displays a double-peak pattern. The transpiration rate presents a cubic relation with water content in soil and an exponential relation with stomatal resistance. The transpiration rate correlates significantly with the main environmental factors such as air temperature, relative humidity and photosynthetic active radiation. The air temperature is the main factor which affects transpiration.