中国沿海梭鱼群体的形态学比较研究

Morphological Variation of Redlip Mullet(Liza haematocheilus) in Different Geographical Populations Along China Coast

对采自营口、东营、青岛、温州和广州近海的5个梭鱼(Liza haematocheilus)群体、164个个体进行了7个可数性状和33个可量性状的测量,并利用主成分分析、判别分析、单因子方差分析和聚类分析等方法进行了群体间形态差异比较研究。各个群体的分节特征值存在较大程度的交叉,群体间无明显差异,难以作为梭鱼群体划分的依据。对可量性状的主成分分析结果表明,前9个主成分的累积贡献率为79.6%,根据第1和第2主成分绘制的散点图显示,各群体之间有较大程度的重叠;采用对判别贡献较大的8个变量,分别构建了5个梭鱼群体的判别公式,其综合判别准确率达83.5%;在单因子方差分析中,各群体在大多数变量中都存在显著差异(P=0.05),说明梭鱼各个群体间已经出现了一定程度的形态特征差异;聚类分析结果显示,5个群体划分为2大组,但聚类的结果与地理分布不一致,这种现象可能是由梭鱼的形态差异受环境因素的影响大于受地理距离的影响所造成的。

Seven meristic characters and thirty-three morphological characteristics were measured and the data were analyzed by the principle component analysis method, discriminatory analysis one-way ANOVA and cluster analysises to study the morphological variations among five populations of Liza haematochei- lus （164 individuals） collected from Yingkou, Dongying, Qingdao, Wenzhou and Guangzhou. The value of meristic counts presented a large degree of cross range among 5 populations. The result of principal component analysis indicated that nine principal components were constructed by factor loading, the cu- mulative contribution ratio was 79.6%. Scatter plots of scores on the first and second morphological char- acteristics showed that there was extensive overlap in five populations. The discriminant functions of five populations were established, and the total accuracy of discrimination was 83.5 %. The multivariate anal- ysis and one-way ANOVA results revealed that there were significant differences （P=0. 05） among populations in most morphological characteristics, also suggest that differences of morphological characteristics existed in L. haematocheilus populations. In the cluster analysises, five populations were divided into two clades which were not consistent with the geographic distribution, which implied that environment factors effected more than geographic isolation.