沙棘属植物叶片碳稳定同位素含量与气候的关系

本试验以131个沙棘属植物种群为研究对象,通过测定其叶片碳稳定同位素(δ¹³C)值,分析了碳稳定同位素特征与环境因子之间的关系。结果表明: 沙棘属植物叶片的δ¹³C值介于-24.65‰～-29.11‰,平均值为-26.97‰,属于C3植物,叶片δ¹³C值变异系数为种内大于种间,表明环境因子是影响沙棘属植物叶片δ¹³C含量变化的主导因素。沙棘属植物叶片的δ¹³C值与经纬度的变化无显著相关,与海拔呈显著负相关。通过建立回归方程: δ¹³C(‰)=0.118VAP-0.007GST-0.000028RDA-20.721(R²=0.212,P<0.0001),说明影响沙棘属叶片δ¹³C值最主要的因素是水蒸气压(VAP)、生长季温度(GST)和太阳辐射(RDA)。研究结果可为沙棘属植物对全球气候变化的响应提供理论依据。

Relationship between climate and leaf carbon stable isotope of Hippophae

We analyzed the relationship between carbon stable isotope characteristics of 131 Hippophae populations and environmental factors by measuring the foliar δ¹³C value in Hippophae. The results showed that the foliar δ¹³C values of Hippophae ranged from^-24.65‰ to-29.11‰, with an average of-26.97‰. Hippophae species were C3 plants. For the foliar δ¹³C values, the coefficient variation at intraspecific level was higher than that at interspecific level, indicating that environmental factors should be main factors driving the variations of leaf δ¹³C. The δ¹³C values had no significant correlation with latitude and longitude, but were negatively correlated with altitude. The regression equation was δ¹³C(‰)=0.118VAP-0.007GST-0.000028RDA-20.721(R²=0.212,P<0.0001). Water vapor pressure(VAP), growing season temperature(GST), and radiation(RDA) were the major factors affecting foliar δ¹³C values. Our results could provide a theoretical basis to understand the responses of Hippophae species to global climate change.