中文摘要：

以浙江省典型树种——香樟（Cinnamomum camphora）为研究对象,通过大棚控制实验,研究在酸沉降（p H 4.0和5.6）和汞胁迫（0、0.5和10 mg·kg^-1）的复合作用下香樟幼苗生理生态特性的响应。结果表明：酸沉降和汞胁迫均显著提高了香樟幼苗的叶绿素b/a;对于叶鲜重,在低p H值下,与低浓度的汞处理相比,高浓度汞处理对叶鲜重有显著的促进作用,而在高p H值下,各汞处理浓度间差异不显著;虽然酸沉降和汞胁迫的交互作用对总干重没有影响,但其显著降低了香樟幼苗的根冠比。另外,随着时间的延长,各处理组合下,株高、基径和叶片数呈增加趋势,但在重度汞处理下三指标增加较为缓慢且初期差异不大,后期差异较大。显然,汞处理效应不仅受酸沉降的影响且受处理时间的影响。总之,在酸沉降下,虽然汞胁迫对香樟幼苗产生了一定的伤害症状,但香樟幼苗适合度并没有显著改变,说明香樟幼苗通过适应性策略能很好地适应环境的变化并可作为生态恢复的优良树种。

英文摘要：

In this study,Cinnamomum camphora,one of typical trees in Zhejiang Province,was chosen to explore the response patterns of physio-ecological properties of plants under simulated acid deposition（ p H 4.0 and 5.6） and Hg stress（ 0,0.5 and 10 mg·kg^-1） in greenhouse experiment. The results showed that acid deposition and Hg stress significantly increased the ratio of chlorophyll b and chlorophyll a. Under low p H,the higher Hg treatment（ 10 mg·kg^-1） significantly increased the fresh weight of leaf compared with low Hg treatment（ 0.5 mg·kg-1）,while under high p H,Hg treatments had no such effects. Meanwhile,acid deposition and Hg stress had no interactive effects on total dry biomass,but significantly decreased the root / shoot ratio. With the expansion of treatment duration,the height,basal diameter and leaf number increased,but they increased more slowly under higher Hg treatment. Also,for the three traits,the differences between the treatment groups were minor in the early period but significant in the later period.Obviously,the effects of Hg treatment were not only affected by acid deposition but also by treatment duration. Although acid deposition and Hg stress incurred some damages to the growth of the plants,they did not pose negative impacts on the fitness. It is suggested that the C. camphora seedlings could adapt to the alteration of environment and could be treated as a species in ecological restoration.