Study On Water Character Of Twelve Ecological Forest Species Trees In Zhejiang Province

In China Zhejiang region, although it located in humid areas, but because the uneven distribution of precipitation and seasonal drought stress, combined with the excessive interference of human activities, forest vegetation has been destroyed. The region also has serious soil erosion, water scarcity; the ecological problems have become increasingly more serious. Moreover fire protection forest, coastal shelterbelt and urban landscaping tree species in Zhejiang regin are single, configuration mode is very monotonous.Many scholars have done the measurement of moisture characteristics for China’s northern trees species and have achieved remarkable results. However, the measurement of water characteristic parameters for common ecological forest tree species in Zhejiang with P-V technology for in spring, summer and antumn season have been reported rarely. This experiment has been done in the East Campus of Zhejiang Forestry College, and its test samples are native trees of Elaeocarpus galbripetalus, Schima superba, Euonymus japonicus, Michelia figo, Photinia serrulata, Cyclobalanopsis glauca, Camellia japonica, Viburnum odoratissimum, Metasequoia glyptostroboides, Cinnamomum camphora, Myrica rubra, Osmamthus fragrans.12 kinds. By researching and obtaining the water characteristics of the 12 species in spring, summer, autumn season with PV technology, and comparing the strength of its drought resistance, the results are as follows:(1) 12 kinds of anti-drought ability derived from woody plants which are not the same with comparring the different water parameters. Gnerally, it is believed that osmotic potential at turgor loss point (πp) is a measure of the ability of plants the best indicator of drought resistance. In accordance with the average size of three tree species in the spring, summer and autumn seasons, the order of 12 species drought-resistance ability is Cyclobalanopsis glauca> Photinia serrulata> Schima superba> Osmamthus fragrans> Myrica rubra> Elaeocarpus galbripetalus> Cinnamomum camphora> Euonymus japonicus> Metasequoia glyptostroboides> Camellia japonica> Viburnum odoratissimum > Michelia figo. The results showed that the strong ability of drought resistance of twelve species have Cyclobalanopsis glauca, Photinia serrulata, Schima superba, Osmamthus fragrans, Myrica rubra, the abated ability of drought resistance of twelve species have Elaeocarpus galbripetalus, Cinnamomum camphora, Euonymus japonicus, Metasequoia glyptostroboides, the weakest ability of drought resistance of twelve species have Camellia japonica, Viburnum odoratissimum, Michelia figo.(2) 12 species of the five water parameters are different in three seasons, and they sizes, scopes and trend of change are different for each species. It illustrated the 12 species to regulate their own in order to adapt to arid environment by three different ways in the three seasons.(3) The comprehensive evaluation results of drought-resistant showed that the drought-resistance ability of 12 kinds trees in spring, summer and autumn season of three different sequences. In spring, the results of comprehensive evaluation of bound water / free water is similar shows that 12 species’own ability for storing water plays an important role in evaluation of drought resistance in spring. In summer, the results of comprehensive evaluation and the result of the initial plasmolysis at the time for osmotic potential are similar shows that 12 species of self-regulation of the permeation for its drought resistance plays an important role in the summer. In autumn, the result of comprehensive evaluation and the result of the initial plasmolysis for the osmotic potential are similar shows that 12 species’own regulation ability of the permeation for its drought resistance plays an important role.(4) By correlation analysising for the 12 species shows that the correlation of the water parameters of the 12 species are different between the different tree species, it illustrates that the parameters of the water are different in the role of plants drought resistance ability and also different in the mechanism.