深圳湾外来红树海桑叶片建成成本及其入侵潜力分析

Abstract

本文对深圳湾外来红树海桑(Sonneratia caseolaris)的叶片建成成本CC和其它特征指标进行分析，结果表明：海桑具有最低的叶片建成成本和最高的比叶面积SLA，其单位质量建成成本CCM比本地红树低6.3%，单位面积建成成本CCA比本地红树低32.2%；SLA却比本地红树高38.6%。此外，海桑的叶片热值和碳含量也均低于本地红树，而氮含量却比本地红树高。低CC、热值和碳含量以及高的SLA和氮含量导致海桑具有比本地红树更高的树高和更大的胸围，使两者分别比本地红树高50%和125.6%。因此，低CC和高SLA使外来红树海桑在深圳湾的入侵潜力增加，其入侵性不可忽视。 Leaf construction cost (CC) and other growth traits of alien Sonneratia caseolaris in Shenzhen Bay were studied to evaluate the invasive potential of this alien mangrove species after introduced to Shenzhen, their new habitat. Results showed that the CC of S. caseolaris was the lowest, while the specific leaf area (SLA) was just the opposite. CC per unit mass (CCM) and CC per unit area (CCA) were 6.3% and 38.6%, respectively lower than those of native mangroves, while SLA was 38.6%, higher than the natives. In addition, leaf caloric values and C concentrations of S. caseolaris were lower than the native mangroves significantly while the N concentrations were the opposite (P < 0.05). Lower CC, caloric values and C concentrations but higher SLA and N concentrations led this alien mangrove species to grow higher and bigger than the natives (50% and 125.6% in height and chest circumference, respectively). Therefore, lower CC but Higher SLA would add the invasive potentials to S. caseolaris and the invasiveness of this alien mangrove species should not be neglected.