廉州湾滨海湿地潮间带大型底栖动物群落次级生产力

Secondary productivity of benthic macrofaunal community in intertidal zone of Lianzhou Bay,China

于2011年1月、4月、7月和10月开展广西廉州湾的裸滩、红树林和茳芏(Cyperus malaccensis)盐沼3种湿地生境类型的潮间带大型底栖动物群落季节动态调查,采用Brey经验公式估算各生境次级生产力。结果表明:共采集到潮间带大型底栖动物8门156种,其中裸滩生境有136种,红树林生境85种,盐沼生境29种;站位平均种数为裸滩9.5±4.8种,红树林9.5±3.9种,盐沼5.9±1.9种,同时,各类群占总种数比例大小规律一致,为软体动物门>节肢动物门>环节动物门>脊索动物门>其他;盐沼生境大型底栖动物群落结构变化较小,宁波泥蟹(Ilyoplax ningpoensis)优势很明显,随着水体盐度上升,红树林和裸滩优势种由适应低盐环境向适应高盐环境的种类变化;廉州湾潮间带大型底栖动物群落的次级生产力平均为15.88g·m-2·a-1,裸滩、红树林和盐沼生境分别为16.16、9.97、3.88g·m-2·a-1;P/B值平均为0.70,3种生境分别为盐沼1.02,裸滩0.70,红树林0.65;廉州湾潮间带大型底栖动物年湿质量生产量为14623t。水体盐度和植被类型是影响廉州湾潮间带大型底栖动物群落结构的优势种群以致次级生产力的空间分布变化的主要因素。

A seasonal investigation was conducted on the dynamic changes of benthic macrofaunal community in the three types of intertidal habitats, i.e., bare flat, mangrove forest, and Cyperus malaccensis saltmarsh, in Lianzhou Bay in January, April, July, and October, 2011, and the Brey＆rsquo;s empirical formula was applied to estimate the secondary productivity of benthic macrofaunal community in the three habitats. A total 156 species belonging to 8 phyla of intertidal benthic macrofauna were collected, among which, 136, 85, and 29 species were recorded in bare flat, mangrove forest, and saltmarsh habitats, respectively. The average species abundance per sampling station was 9.5±4.8 species in bare flat, 9.5±3.9 species in mangrove forest, and 5.9±19 species in saltmarsh, respectively. In all the three habitats, the percentages of different categories to total species followed the same decreasing order of Mollusk 〉 Arthropod 〉 Annelid 〉 Chordate 〉 other categories. The community structure of the benthic macrofauna in saltmarsh had smaller change, with Ilyoplax ningpoensis significantly dominated. In mangrove forest and bare flat, the dominant species changed with the water salinity. In the intertidal zone of Lianzhou Bay, the average secondary productivity of the benthic macrofaunal community was 15.88 g＆middot;m-2＆middot;a-1, and that in bare flat, mangrove forest, and saltmarsh was 16.16 g＆middot;m-2＆middot;a-1, 997 g＆middot;m-2＆middot;a-1, and 3.88 g＆middot;m-2＆middot;a-1, respectively. The average P/B ratio in the intertidal zone was 0.70, and that in bare flat, mangrove forest, and saltmarsh was 0.70, 0.65, and 1.02, respectively. The annual secondary production in the intertidal zone was 14623 t （FM）. Water salinity and vegetation type were the major factors affecting the community structure of the intertidal benthic macrofauna, and further, the spatial distribution of the secondary productivity of the benthic macrofauna in Lianzhou Bay.