摘要
为了探讨未来降雨变化对半干旱毛乌素沙地常绿灌木沙地柏（Ｓａｂｉｎａ ｖａｌｇａｒｉｓ Ａｎｔ．）荧光特征和气体交 换的影响，在内蒙古鄂尔多斯沙地草地生态站开展了水分梯度实验。结果表明：水分梯度对初始荧光、可变荧光、最 大量子产量、最大荧光／初始荧光比的影响均不显著；相反，显著影响净光合比率、气孔导度、蒸腾速率、胞间ＣＯ２／ 大气ＣＯ２、水分利用效率、表观ＣＯ２利用效率和表观光能利用效率。这些结果指示，在一个实验期，土壤水分变化显 著影响沙地柏幼苗的“表观性”气体交换和资源利用效率，并不显著影响光系统Ⅱ的“内在性”荧光特征。气体交换 和资源利用效率对水分变化的响应格局因生理指标不同而存在差异。净光合速率对接近土壤最大持水量的施水处 理最敏感。
To examine the effects of future rainfall change on the physiological characteristics of Sabina vulgaris, an evergreen shrub growing in the semi-arid Mu Us sandy region, a water gradient experiment was conducted at the Ordos Grassland Ecological Station in Inner Mongolia. The results showed: minimal fluorescence(F0), variable fluorescence(Fv), Fm/F0, Fv/Fm were not significantly affected by the water gradient, while in contrast, net photosynthesis ratio, stomatal conductance, transpiration rate, ratio of substomatal CO2 to atmospheric CO2, water use efficiency, apparent light use efficiency and apparent CO2 use efficiency were all influenced significantly by changing water status. These results indicate that while the water gradient has a significant effect on external features, such as gas exchange and resource use efficiency, it has no significant influence on the internal fluorescence features of photosynthesis system . The patterns of the responses of the gas exchange and resource use efficiency to water change varied with various physiological indices. Net photosynthesis rate responded most sensitively to soil water content relative to soil field capacity.
出处
《植物生态学报》
CAS
CSCD
北大核心
2000年第5期630-634,共5页
Chinese Journal of Plant Ecology
基金
中国科学院资源与生态环境研究重大项目和重点项目!(KZ951-B1-108&KZ952-S1-126)
关键词
沙地柏幼苗
沙地
荧光特征
气体交换
水分梯度
Sabina vulgaris seedlings, Semi-arid sandy region, Chlorophyll fluorescence, Gas exchange, Resource use efficiency
