山东东营和烟台潮间带海草床食物网结构特征

为了探明海草床内主要生物类群间的营养关系以及食物网结构, 作者于2018年8月分别在东营黄河口潮间带和烟台西海岸潮间带海草床采集大型底栖生物样品, 采用δ ¹³C和δ ¹⁵N稳定同位素方法, 对生物样品的碳、氮同位素组成进行了测定和分析。结果表明: 东营海草床内生物的δ ¹³C、δ ¹⁵N值范围分别为-21.99‰至-12.13‰和5.23‰-11.05‰, 烟台海草床内生物的δ ¹³C、δ ¹⁵N值范围分别为-18.11‰至-14.06‰和6.60‰-10.22‰。东营海草床主要生物的营养级范围为2.00-3.85, 烟台海草床主要生物的营养级范围为2.00-3.15。根据δ ¹⁵N值计算所得的营养级图分析可知两区域海草床内初级消费者主要为滤食性双壳类和多毛类, 次级消费者为植食性或杂食性甲壳类,肉食性鱼类和腹足类。与近海海域大型底栖生物食物网相比, 海草床内底栖生物的营养级均值普遍较低。

Food web characteristics of seagrass beds in intertidal of Dongying and Yantai,Shandong Province

To understand the nutritional relationship among benthic organisms and the food web characteristics in seagrass beds, we collected macrobenthic organisms in intertidal zones of the Yellow River Delta of Dongying and the west coast of Yantai in August 2018. We used δ ¹³C and δ ¹⁵N stable isotopes determine trophic position. The range of organisms isotopic values in the Dongying seagrass bed were -21.99‰ to -12.13‰ for δ ¹³C and 5.23‰ to 11.05‰ for δ ¹⁵N; and -18.11‰ to -14.06‰ (δ ¹³C) and 6.60‰ to 10.22‰ (δ ¹⁵N) in the Yantai seagrass bed. In the Dongying seagrass bed, the trophic level of main organisms ranged from 2.00 to 3.85, while in the Yantai seagrass bed the trophic range was from 2.00 to 3.15. According to δ ¹⁵N value calculations, we found that the primary consumers in these two area’s seagrass bed were filter feeding bivalves and polychaetes; the secondary consumers were plant-eating or omnivorous crustaceans, carnivorous fish and gastropods. Compared to offshore habitats, the average trophic position of macrobenthic organisms in seagrass beds was relatively low.