Preliminary Report on Northward Introduction Experiment of Several Mangrove Plants Along the Southern Coast of Zhejiang Province

To screen out the introduced mangrove species adaptive to the natural conditions in Wenzhou area, different provenances of mangrove species were experimented with and the annual growth of the experiment plots was investigated. The results showed that survival rate of Kandelia candel, Sonneratia apetala, Aegiceras corniculatum and Excoecaria agallocha was 77%, 73%, 70% and 15% respectively, indicating the former 3 species could overwinter safely in the studied area. Whereas all the saplings of Laguncularia racemosa, Bruguiera gymnorhiza, Bruguiera sexangula var. rhynchopetala, Rhizophora stylosa, Acanthus ilicifolius and Avicennia marina died in the winter. Compared to the values measured in the summer, the increment amplitude of relative conductivity (RC) value of the tested species at 0℃ temperature was in the order that of Laguncularia racemosa ＞ Sonneratia apetala ＞ Aegiceras corniculatum ＞ oneyearold Kandelia candel ＞ eightyearold Kandelia candel. The maximum increase of superoxide dismutase (SOD) value happened to Aegiceras corniculatum whose value measured at 0℃ increased by 105% compared to that of measured in the summer. While the SOD values of Kandelia candel and Laguncularia racemosa did not change much with the seasons. The proline (PRO) content in the leaves of Laguncularia racemosa in the winter increased by 2854% compared to the summer value, but there was very little change in this index for Sonneratia apetala and eightyearold Kandelia candel along the seasonal change. The comprehensive analyses showed that Sonneratia apetala, Aegiceras corniculatum, Excoecaria agallocha and Kandelia candel could safely survive the winter in the south part of Zhejiang Province, while the adaptability of other mangrove tree species to the studied area should be further experimented.