土壤含水量和光照对祁连圆柏光合生理指标的影响

Effects of Soil Water Content and Light on Physiological Indexes of Juniperus przewalskii Kom.

采用人工控制土壤水分的方法,测定不同土壤含水量条件下祁连圆柏苗木的蒸腾速率、净光合速率和水分利用效率等指标,分析祁连圆柏在不同土壤含水量和光照条件下光合生理响应特征及其变化规律。结果表明:祁连圆柏的蒸腾速率、净光合速率均随着土壤含水量的增加呈先上升后下降的趋势。光合有效辐射在400-2000μmol/(m2·s)范围内,祁连圆柏的净光合速率、蒸腾速率和水分利用率均呈现最高值。土壤水分含量在17.04%、15.54%和11.77%时,祁连圆柏的净光合速率、蒸腾速率和水分利用率达到最高值,土壤含水量11.7%-17.04%是祁连圆柏生长最适宜的土壤水分区间。

In thiSexperiment,the transpiration rate,net photosynthetic rate and water use efficiency( WUE )of JuniperuSprzewalskii Kom.under different soil moisture conditionSwere measured by artificial control of soil moisture.The characteristicSof photosynthetic physiological response and itSchanging rule under different soil water content and light conditionSwere analyzed.The resultSshowed that the transpiration rate and net photosynthetic rate of J.przewalskii increased at the beginning and then decreased with the increase of soil moisture content.In the range of 400-2 000μmol/(m2 ·s),net photosynthetic rate,transpiration rate,and water content of J.przewalskii under different soil water content were obtained.When the soil moisture content waS17.04%,15.54% and11.77%,the net photosynthetic rate,transpiration rate and water use efficiency of J.przewalskii reached the highest value.Soil water content11.7%-17.04% iSthe most suitable soil moisture range for the growth of J.przewalskii .