元宝枫等3个树种枝干水容特征

Studies of the Characteristics of Water Capacitance in the Branches and Stems of Pinus tabulaeformis,Platycladus orientalis and Acer truncatum

对元宝枫、油松、侧柏等3个树种枝条和树干水容特征进行了研究.结果表明:3个树种枝条水容值的日变化均表现为自6:00开始先行递减,12:00或14:00后缓慢回升,直至18:00上升至一定数值,其季节变化为雨季大于旱季;3个树种树干水容值的日变化也表现为先降后升,但其季节变化为雨季小于旱季;树干水容要大于枝条水容,而且上部枝干水容的日变化较中下部的变化明显.树体枝干水容特征能很好地反映林木与环境水分的关系,对蒸腾耗水具有一定的调节作用.

The characteristics of water capacitance in the branches and stems of Pinus tabulaeformis, Platycladus orientalis and Acer truncaturn were studied in this paper. The result shows that the relative water capacitance in the branches of the three sample trees stays basically unanimous. The diurnal fluctuation of water capacitance in the branches is reduced from 6：00 am to 12..00 am or 14：00 pm and then stays stable until its rise to a certainty point at 18：00 pro. The seasonal variation of the relative water capacitance shows higher in rainy season than in dry season. The diurnal fluctuation of the water capacitance in the stems of the three sample trees behave in the same way as that of the branches. It is first reduced and then gets back. But the seasonal variation of the relative water capacitance of stems shows lower in rainy season and higher in dry season. The water capacitance of stems is bigger than that of the branches. The diurnal fluctuation of the stem capacitance at the top of the tree is changed obviously. The characteristic of the water capacitance of the tree species reflects the water relation between the tree and the stand conditions. It can influence the transpiration water consumption action.