广西红树蚬的分布特征及影响因素分析

Characteristics of Distribution and the Influential Factors of Mangrove Clam,Polymesoda erosa(Solander 1786),in Guangxi

【目的】研究红树蚬(Polymesoda erosa)分布密度与潮高、底质和红树根际等环境因子的关系。【方法】在广西廉州湾和珍珠湾红树林设置5条断面25个取样站进行采样调查,运用单因素方差分析(one-way ANOVA)和主成分分析的统计方法对数据进行分析。【结果】红树蚬多见于高潮带而鲜见于低潮带,红树蚬分布密度从高潮位向低潮位递减。红树根际与林内空地红树蚬分布密度差异不明显(P>0.05),不同红树植物树种根际红树蚬的分布密度差异不明显(P>0.05)。【结论】沉积物紧实度和盐度是红树蚬分布的影响因素。

[Objective]To explore the relationship between the densities of mangrove clam （Polymesoda erosa ）and their environmental factors,including tidal height,sediments,and rhizospheres of mangrove trees.[Methods]Samples were collected in twenty-five stations along five transects set in Lianzhou Bay and Zhenzhugang Bay of Guangxi,and analyzed by using the statistics methods of one-way ANOVA and principal component analysis.[Results]Mangrove clams usually occur in high tidal zone and are scarcely found in low tidal zone,and their density decreases gradually from high tidal zone to low tidal zone.There was no significant difference in the densities between the mangrove clams found in open areas and rhizospheres of mangrove trees.There was also no significant difference in the densities among the mangrove clams found in rhizospheres of different mangrove trees.[Conclusion]Packing degree and salinity of sedi-ments were among the influential factors which have impacts on mangrove clam distribution.