The base of nutritional support for the gray snapper (Lutjanus griseus): an evaluation based on a combined stomach content and stable isotope analysis
The base of nutritional support for the gray snapper (Lutjanus griseus): an evaluation based on a combined stomach content and stable isotope analysis
复制标题
灰鲷鱼（Lutjanus griseus）营养支持的基础：基于胃内容物和稳定同位素分析的综合评估
DOI：
--
复制
发表时间：
1989
影响因子：
1.5
通讯作者：
S. Macko
中科院分区：
文献类型：
--
作者：
P. Harrigan;J. Zieman;S. Macko
结合胃内容物和稳定同位素分析，以确定海草是否提供了一个基础的营养支持的灰笛鲷，笛鲷。结果提供了一个定量评估的相对贡献的碳和氮从各种主要有机源灰笛鲷采取的每一个红树林和海草为主的位置在南佛罗里达。胃含物分析表明，两个地区的灰口笛鲷具有相似的食物，主要由对虾组成（>60%）。同位素结果提供了食物网之间的碳值的基础上的区别。海草区各组分的6 '3C值均大于-17%0，而红树林区各组分的6' 3C值均小于190/00。定量估计表明，灰笛鲷从海草区获得超过90%的碳和氮的沉积物或水柱颗粒有机质。灰笛鲷从红树林地区提供的碳和氮从这些来源，除了碎屑。主要贡献者似乎是来自水柱和微咸水草，Ruppia maritima的颗粒有机物。总之，这些来源占猎物项目膳食碳和氮的最终来源的35%至100%。这些结果表明，在这两个食物网的碳和氮是从碎屑基地通过类似的机制，并强调使用多种同位素作为定量评估食物网的工具。海草是佛罗里达南部和加勒比海沿岸浅沃茨的主要初级生产者。由于海草床具有改变自然环境和提供食物来源的能力，各种海洋生物都在海草床中栖息。由于几个海洋物种的丰度不断下降，因此需要确定和量化海草对海洋生物重要的方面。这项研究的重点是在食物网的灰色笛鲷，Lutjanus griseus，南佛罗里达的商业重要的鱼类海草的作用。海草在支持灰笛鲷种群中的营养作用仅通过胃内容物分析定性地提出（Randall，1960年; Tabb和Manning，1961年; Starck和Schroeder，1964年; Odum和Heald，1972年）。这些研究表明，灰笛鲷，特别是青少年，从海草床获得猎物。尽管灰笛鲷和海草之间有明显的联系，但这些动物对海草床的依赖性尚未得到确定。本研究采用胃内容物和稳定同位素分析相结合的方法来追踪灰笛鲷的食物网，并定量确定灰笛鲷是否依赖海草作为营养支持的基础。稳定的碳同位素经常用于追踪动物的饮食（DeNiro和Epstein，1978; Fry和帕克，1979; Macko等人，1982年）。这些研究是基于生物体的l3 c/12 e比率与其食物来源的l3 c/12 e比率非常相似。在示踪剂研究中使用单一元素的同位素可能不足以区分同位素相似的食物来源或两种以上食物来源的混合物。这一不足可以通过以下方式减少：
A combined stomach content and stable isotope analysis was used to determine ifseagrass provides a base of nutritional support to the gray snapper, Lutjanus griseus. The results provided a quantitative evaluation of the relative contribution of carbon and nitrogen from various primary organic sources to gray snapper taken from each a mangrove and a seagrass dominated location in south Florida. Stomach content analysis revealed that gray snapper from the two areas had similar diets which were primarily composed of penaeid shrimp (>60%). Isotopic results provided a distinction between food webs on the basis of carbon values. The 6'3C of components from the seagrass location were greater than -17%0 in contrast to values of less than 190/00 for those from the mangrove area. Quantitative estimates indicated that gray snapper from the seagrass area derived more than 90% of their carbon and nitrogen from sediment or water column particulate organic matter. Gray snapper from the mangrove area were supplied by carbon and nitrogen from these sources in addition to detritus. The main contributors appeared to be particulate organic matter from the water column and the brackish water grass, Ruppia maritima. Together, these sources accounted for 35 to 100% of the ultimate source of prey item dietary carbon and nitrogen. These results suggest that within both food webs carbon and nitrogen are transferred from a detrital base by similar mechanisms and emphasize the use of multiple isotopes as a tool for quantitatively evaluating food webs. Seagrasses are major primary producers in the shallow coastal waters of south Florida and the Caribbean. As a consequence of their ability to modify the physical environment and to provide a food source, seagrass beds are inhabited by a variety of marine organisms. A need to identify and quantify aspects of seagrasses that are important to marine organisms has emerged in response to the declining abundance of several marine species. This study focussed on the role of seagrass in the food web of the gray snapper, Lutjanus griseus, a commercially important fish species of south Florida. The nutritional role of seagrass in supporting populations of gray snapper has only been suggested qualitatively by analysis of stomach contents (Randall, 1960; Tabb and Manning, 1961; Starck and Schroeder, 1964; Odum and Heald, 1972). These studies indicated that gray snapper, particularly juveniles, obtain prey from seagrass beds. Despite an apparent association between gray snapper and seagrass, dependence of these animals on seagrass beds has not been firmly established. This study employed a combined stomach content and stable isotope analysis to trace the food web of the gray snapper and quantitatively determine if gray snapper are dependent on seagrass as a base of nutritional support. Stable carbon isotopes have been frequently used to trace the diets of animals (DeNiro and Epstein, 1978; Fry and Parker, 1979; Macko et aI., 1982). Such studies are based on the close resemblance of the l3c/12e ratio of the organism to that of its food source. The use of isotopes of a single element in a tracer study may be inadequate to distinguish between isotopically similar food sources or a mixture of more than two food sources. This inadequacy can be reduced by the