Comparative Studies on Seasonal Water Use of Gymnosperms and Angiosperms in South China

Abstract:

In order to understand the water use characteristics of gymnosperms and angiosperms in warm area, the sap flow of two gymnosperms, Taxodium ascendens and T. distichum, two angiosperms, Liquidambar formosana and Michelia chapensis, was continually monitored by using Granier's thermal dissipation probes (TDP) in Guangdong Province of southern China. The results showed that whole tree transpiration rate and daily water consumption were positively correlated with photosynthetically active radiation and vapor pressure deficit. In the dry season, the water transport capacity in Taxodium ascendens and T. distichum was significantly smaller than that in L. formosana and M. chapensis, while it was just the reverse in the wet season. So, these could provide scientific basis for landscape gardening and management in south China.

Key words:Gymnosperms;Angiosperms;Transpiration;Hydraulic conductance;South China