湛江红树林保护区软体动物群落结构与生态位分析

The Structure of the Mollusca Communityand Niche Analysis in ZhangjiangMangrove Nature Reserves

对广东湛江红树林保护区高桥核心区软体动物进行采样调查,共采集软体动物20种,隶属1门2纲13科.其中桐花树+红海榄(Acgiceras corniculatum+Rhizophora stylosa)群落10种,桐花树+秋茄(Acgiceras corniculatum+Kandelia candel)群落6种,桐花树+白骨壤(Acgiceras corniculatum+Avicennia marina)群落13种,白骨壤+桐花树群落(Avicennia marina+Acgiceras corniculatum)16种.对软体动物密度数据进行季节和红树植物群落类型进行无重复双因素方差分析,结果显示软体动物栖息密度主要受红树植物群落类型而不是季节的影响.对定量取样中获得的20个物种以Shannon-Wiener指数为基础进行了生态位宽度测定,以Pianka重叠指数为基础进行了生态位重叠值分析,结果表明琵琶拟沼螺(Assiminea lutea)、黑口滨螺(Littoraria melanostoma)和粗糙滨螺(Littorina scaber)的生态位较宽,均为2.0以上,它们之间的生态重叠值也较高,均为0.70以上.以密度数据4次开方为基础,利用欧氏距离进行群落物种的系统聚类分析,结果表明物种的聚类可以反映群落中物种生态位重叠值,但是生态位宽度的研究,要针对不同物种来分析.非度量多维标度排序分析也支持以上结果.研究表明,物种生态宽度、物种之间的生态位重叠值与物种的分布与数量密切相关,反映了软体动物群落中各物种对生境资源利用能力的强弱.

This study was conducted to explore the structure of the mollusca community and niche in Zhangjiang Mangrove Nature Reserves. The mollusks community in the four kinds of mangrove communities in the core region of Gaoqiao town were studies. A total of 20 species in the investigation, belonging to 13 families, 2 classes and 1 phyla were collected. The numbers of species found in the Acgiceras corniculatum ＋ Rhizophora stylosa , Acgiceras corniculatum ＋ Kandelia candel , Acgiceras corniculatum ＋ Avicennia marina, Avicennia marina ＋ acgiceras corniculatum community were 10, 6 , 13 and 16, respectively. Taking season and habitat as analysis factors, we found that the mollusk inhabited density was significantly different among the four habitats （P 〈0.05）, but not significantly different among the four seasons （P〉0.05） by the method of nonrepetitive double factors variance analysis. The tests of the Shannon-Wienerrs niche breadth index and the Pianka＇s niche overlaps index, showed that Assiminea lutea , Littoraria melanostoma and Littorina scaber had broad niche breadths（above 2.00） ; the niche overlaps among them was high（above 0.70）. Based on the fourth power of mollusks density, using the Hierarchical Cluster of between-groups linkage method and the Non-matric Multidimentional Scaling method, we found that the method can reflect the niche overlaps among mollusks, but the niche breadths should base on the different species to analytical. The results revealed that the niche breadth and the niche overlap reflected the species distribution, the quantity characters and the species ability to utilize the environmental resource.