生态学报Issue(23)：7589-7597,9.DOI:10.5846/stxb201404200779
基于碳、氮稳定同位素的厦门筼筜湖两种优势端足类食性分析
Feeding habits for two dominant amphipod species in the Yundang Lagoon based on stable carbon and nitrogen isotope analysis
摘要
Abstract
Amphipods are common, key grazers in coastal macroalgal communities. Understanding their feeding habits will help us predict the fate of primary producers in macroalgal-based ecosystems and the role of amphipods in the detritus and grazing food chains. The feeding habits of amphipods are frequently reported; however, these data are primarily obtained from laboratory experiments. Considering that amphipod feeding selectivity is influenced by various factors such as habitat, food availability, morphological traits, and nutritional value of food sources, differences between laboratory and field experiments are expected. This study measured stable carbon and nitrogen isotopes (δ13 C and δ15 N, respectively) of two dominant amphipod species, Ampithoe valida and Corophium uenoi, and their potential food sources in Yundang Lagoon, and analyzed spatial variation in their diet. Potential amphipod food sources contained particulate organic matter ( POM) , sedimentary organic matter ( SOM) , and Ulva lactuca and its associated epiphytes. Theδ13 C values ranged from-24.0‰for POM to -11. 8‰ for U. lactuca, and the corresponding δ15 N values from -1. 7‰ to 4. 7‰. There were no significant differences between the δ13 C values of U. lactuca and POM; however, the δ13 C values for sedimentary organic matter ( SOM) and U. lactuca epiphytes were higher in the outer lagoon than the inner lagoon. The difference in δ13 C for SOM between the inner and outer lagoon was mainly explained by spatial shifts in the sources of organic matter, such as POM sedimentation before macroalgal blooms in the inner lagoon and organic debris from decaying U. lactuca in the outer lagoon. Epiphytes mainly contained benthic microalgae, bacteria, and organic debris, so variation inδ13 C may be caused by spatial shifts in epiphyte composition. Other than POM, theδ15N values of the carbon sources were higher in the outer lagoon than in the inner lagoon, and this is largely attributed to differences in the nitrogen sources that are absorbed. This inference is also supported by the spatial variation inδ15 N for phytoplankton cultivated in the laboratory using filtered seawater collected from the Yundang Lagoon. Spatial dietary variation was not obvious for A. valida, which mainly obtained carbon from U. lactuca and associated epiphytes. However, significant spatial variation in diet was observed for C. uenoi, which mainly fed on epiphytes attached to U. lactuca and POM in the inner lagoon, but U. lactuca and associated epiphytes in the outer lagoon. Our results showed that theδ15N content in amphipods was much higher in the outer lagoon in than the inner lagoon, and this variation is largely caused by spatial variation in food sources.关键词
稳定同位素/强壮藻钩虾/上野蜾蠃蜚/端足类/食性/筼筜湖Key words
stable isotope/Ampithoe valida/Corophium uenoi/amphipod/feeding habits/Yundang Lagoon引用本文复制引用
郑新庆,王倩,黄凌风,王建佳,林荣澄,黄丁勇,孙晓红..基于碳、氮稳定同位素的厦门筼筜湖两种优势端足类食性分析[J].生态学报,2015,(23):7589-7597,9.基金项目
福建省自然科学基金面上资助(2014J01127) （2014J01127）
国家自然科学基金面上资助(31272703) （31272703）
