三种红树植物落叶碎屑对海水中多环芳烃吸附作用的实验研究

在实验室条件下，研究了海水中多环芳烃（PAHs）（含苊、菲、）浓度分别为90、900或9000 μg/L时，无瓣海桑（Sonneratia apetala）、秋茄（Kandelia candel）和木榄（Bruguiera gymnorrhiza）不同分解状态落叶碎屑对PAHs的吸附作用。结果显示:在相同PAHs浓度下，无瓣海桑、秋茄和木榄落叶碎屑对PAHs的吸附总量差异显著（p < 0.05），吸附率树种间也差异显著（p < 0.05）。当海水中PAHs的浓度为90和900 μg/L时，3种红树植物落叶碎屑对PAHs的吸附率均是无瓣海桑黑叶最高，分别为32.6%和35.1%。同一树种不同分解状态落叶碎屑对PAHs的吸附规律因树种而异:秋茄棕叶和黑叶对PAHs的吸附率均随着PAHs浓度的增加而增加；木榄棕叶和黑叶对PAHs的吸附率均随着PAHs浓度的增加，先上升（从90 μg/L到900 μg/L），然后下降（从900 μg/L到9000 μg/L）；无瓣海桑棕叶对PAHs的吸附率是随着PAHs浓度的增加而增加，而黑叶却随着PAHs浓度的增加，吸附率先是上升，然后下降。3种红树植物同一分解状态的落叶碎屑对单个PAHs组分的吸附率规律存在差异。同一树种同一分解状态的落叶碎屑对不同PAHs组分的吸附规律也存在差异。

Experimental study on the absorption of PAHs in seawater by the leaf litter of three mangrove species

In the laboratory, the study on the absorption of PAHs (including acenaphthene, phenanthrene, chrysene) in the seawater by the leaf litter of Sonneratia apetala, Kandelia candel and Bruguiera gymnorrhiza was conducted under different decomposed states of the leaf litter.The result showed that the total absorbing amount of PAHs by the leaf litter of S.apetala, K.candel and B.gymnorrhiza varied significantly(P < 0.05) under the same PAHs concentration (90, 900 or 9000 μg/L), and the absorption rate by the leaf litter of the three mangrove species was significantly different.When the concentration of PAHs in seawater is at 90 and 900 μg/L, the absorption rates of PAHs by the brown leaf litter of S.apetala were the highest in the leaf litter of the tree mangrove species, which were 32.6% and 35.1%, respectively.The absorption of PAHs by the leaf litter of the three mangrove species varied as follows:the absorption rate of brown and black leaf litter of K.candel rose with the increase of PAHs concentration; the absorption rate of brown and black leaf litter of B.gymnorrhiza first increased (from 90 to 900 μg/L) and then decreased (from 900 to 9000 μg/L) with the increase of PAHs concentration; the absorption rate of brown leaf litter of S.apetala grew with the increase of PAHs concentration while black leaf litter rose at first and went down later with the continuous increase of PAHs concentration.Laws of absorption rate of the leaf litter of three mangrove species to single PAHs were also discrepant.For the same tree species and the equal decomposed state, the leaf litter absorption rate differed respectively from acenaphthene, to phenanthrene and to chrysene.