| We analyzed the responses of δ13C values of plant leaves to environmental factors (namely, soil water storage, air relative humidity, light intensity, depths of soil, soil organic content, average temperature and soil water content) and the correlations between them, by measuring δ13C values of leaves for 11 plants species from 4 typical communities with different karst rocky desertification backgrounds in a typical karst catchments basin, Huajiang Gorge. It is revealed that, the δ13C values and water use efficient of most species decrease with the increasing of water supply; but a few species exhibit an opposite trend and several others exhibit no change in δ13C values or water use efficiency when these environmental factors varied. Moreover, the correlation analysis indicates that the soil water storage is the leading factor for Pistacia weinmannifolia, Mallotus repandus and Alchornea trewioides，while the depths of soil is essential factor for Nephrolepis cordifolia and Mallotus japonicus var. floccosus, and the light intensity is leading factor for N. cordifolia, Alangium chinense, Broussonetia papyrifera. However, the leading factor for some species like Rapanea kwangsiensis, Sapium rotundifolium and Cipadessa cinerascens are yet not clear, which mean their δ13C values are affected by more comprehensive factors. Hence it could be concluded that high δ13C values of leaves could indicate the adaptability of plants for low water regime, high light and low resource environments. |
