中文摘要：

通过对烟台潮间带大型海藻组织中总碳（TC）、总氮（TN）、氮稳定同位素（δ^15N）和水环境参数的分析,对氮营养盐来源进行了判定,并筛选了合适的指示性藻种。烟台潮间带大型海藻的δ^15N值均位于6.18‰～10.99‰之间,指示了生活污水与养殖排放是海水氮营养盐的主要来源。其中月亮湾（S1）主要受生活污水影响,养马岛（S3）受养殖排放影响更明显,而渔人码头（S2）同时受生活污水和养殖排放影响。绿藻门的孔石莼（Ulva pertusa）和肠浒苔（Enteromorpha intestinalis）对氮营养盐有较好的吸收和贮存能力,同时在利用氮营养盐的过程中分馏作用不明显,较适合于作为氮营养盐来源的指示藻种。

英文摘要：

The total carbon（ TC）,total nitrogen（ TN） and nitrogen stable isotope ratio（ δ^15N） in macroalgal tissue were analyzed in conjunction with environmental variables in seawater to study the nitrogen sources and select effective macroalgal species along the Yantai coast. The results showed that macroalgal δ^15N values at the three sites were all between 6. 18‰ and 10. 99‰,indicating sewage effluent and / or aquaculture discharge being the dominant nitrogen sources. Sewage effluent was dominant factors affecting the nitrogen concentrations in the Moon Bay（ S1）. The nitrogen concentration at the Yangma Island（ S3） was mainly related to aquaculture discharge and the Fisherman Wharf（ S2） was affected by both sewage and aquaculture discharge. Ulva pertusa and Enteromorpha intestinalis in Chlorophyta are identified as effective indicators due to their high nitrogen uptake and minimal nitrogen fractionation.