汞和盐度对三种红树种苗生长影响初探

Influence of Mercury and Salinity on the Growth of Seedlings of Three Mangrove Species

用含汞海水处理桐花树、白骨壤和秋茄的种苗,10.0ppm汞对白骨壤种苗的萌芽时间没有延缓作用,但却影响了桐花树和秋茄的萌芽时间,1.0ppm汞对三种红树种苗的生长没有表现出毒害作用在含汞的盐度为8.75‰和17.5‰的稀释海水培养下,秋茄种苗的生长在二者之间差异不显著,但盐度为17.5‰海水延缓了白骨壤种苗的萌芽时间,抑制了桐花树的萌芽,培养100 d的白骨壤,苗高和重量在两种盐度的稀释海水之间的差异不显著,但桐花树的却差异显著,这表明秋茄和白骨苗种对壤盐度的适应范围较桐花树为宽.

Seedlings of Aegiceras cornlculatum, Avicennia marina and Kandelia can-del were treated with various mercury-containing dilutions of seawater. There was no effect of mercury on the time at which the bud of A. marina emerged from cotyledon. However, the times at which the buds of A. carnlcu-latum and K, candel emerged from plumule were affected, after the treatment of 10 ppm Hg, There were no damaged effect of mercury on the growth of the seedlings of the three species after treatment with 1 ppm Hg. There were no significant changes on the growth of K. candel seedlings between salinity 8.75 ‰ and 17.5 ‰diluted seawater either. The day on which the bud of A. marina emerged from the cotyledon was delayed; the bud of A. cornlcu latum emerged from the plumule was inhibited by salinity 17.5‰ diluted seawater, The weight and height of A. marina seedlings were not significantly altered between salinity 8.75 ‰ and 17.5 ‰ diluted seawater, but that of A. corniculatum seedlings were significantly differed, after the seedlings were treated with various mercury-containing dilutions of seawater for 100 days, so adaptation to salinity of K, candel and A. marina is wider than that of A. corniculatum.