华南地区裸子植物与被子植物季节性水分利用的比较研究

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

摘要:

为了解气候温暖区的裸子植物与被子植物的水分利用异同，利用Granier热消散探针法（TDP）连续监测华南地区裸子植物池杉（Taxodium ascendens）、落羽杉（T.distichum）和被子植物枫香树（Liquidambar formosana）、乐昌含笑（Michelia chapensis）的树干液流，对干湿季裸子植物与被子植物水分利用的差异及其与环境因子的关系进行了研究。结果表明，光合有效辐射和水汽压亏缺与树木的整树蒸腾速率和整树日均耗水量呈显著正相关；干季池杉和落羽杉的整树蒸腾速率与整树水力导度均显著低于枫香树和乐昌含笑；而在湿季则正好相反。这为华南地区园林造景和养护管理提供了科学依据。

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.