Blanar Christopher A, Hornbeck Joseph R, Kerstetter David W, Hirons Amy C
Department of Biological Sciences, Halmos College of Arts and Sciences, Nova Southeastern University, 3301 College Avenue, Fort Lauderdale, FL 33314 USA.
Department of Marine and Environmental Sciences, Halmos College of Arts and Sciences, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, FL 33004 USA.
Heliyon. 2021 Jun 26;7(7):e07413. doi: 10.1016/j.heliyon.2021.e07413. eCollection 2021 Jul.
Artificial reefs may enhance the biological production of reef-associated flora and fauna, but their trophic structure relative to that of natural reefs remains understudied. We assessed trophic relationships by 1) comparing reef fish communities and 2) comparing δC and δN in 43 fish species from both artificial reef sites and adjacent natural reef tracts in Broward County, Florida. We tested the effect of sampling location (artificial, first, and second reef), general feeding strategy (herbivore, omnivore, invertivore, and carnivore), phylogeny, and standard length on δC and δN. The reef fish communities of the artificial and natural reef tracts were significantly different; the artificial sites also exhibited more variability. For all samples, δC and δN ranged from -19.5 to -13.1‰ and 6.7-13.3‰, respectively. Significant effects were detected for both general feeding strategy and phylogeny. Significant differences were also seen in δC and δN profiles between artificial and natural reefs; however, these changes were primarily driven by differences in fish community structure, rather than by changes in the feeding strategy or trophic relationships of individual fish taxa. The trophic guild invertivore was the only group of fish to demonstrate significant isotopic differences between both reef tracts (inner and outer) and reef types (artificial and natural). The artificial reef may act more as a foraging corridor between the natural first and second reef tracts for omnivores and carnivores. If the function of artificial reefs is to provide additional foraging habitat for fishes, then perhaps more time is needed for the trophically important, infaunal invertebrate community to develop similarly to the natural reef environment.
人工鱼礁可能会提高与礁体相关的动植物的生物产量，但其相对于天然鱼礁的营养结构仍未得到充分研究。我们通过以下方式评估营养关系：1）比较礁栖鱼类群落；2）比较佛罗里达州布劳沃德县人工鱼礁站点和相邻天然礁区的43种鱼类的δC和δN。我们测试了采样位置（人工鱼礁、第一礁和第二礁）、一般摄食策略（草食性、杂食性、食无脊椎动物性和肉食性）、系统发育和标准体长对δC和δN的影响。人工鱼礁区和天然礁区的礁栖鱼类群落存在显著差异；人工鱼礁站点的变异性也更大。对于所有样本，δC和δN的范围分别为-19.5至-13.1‰和6.7-13.3‰。一般摄食策略和系统发育均检测到显著影响。人工鱼礁和天然鱼礁之间的δC和δN分布也存在显著差异；然而，这些变化主要是由鱼类群落结构的差异驱动的，而不是由单个鱼类分类群的摄食策略或营养关系的变化驱动的。食无脊椎动物性营养类群是唯一一组在两个礁区（内礁和外礁）和礁体类型（人工鱼礁和天然鱼礁）之间表现出显著同位素差异的鱼类。人工鱼礁可能更多地充当杂食性和肉食性鱼类在天然第一礁区和第二礁区之间的觅食通道。如果人工鱼礁的功能是为鱼类提供额外的觅食栖息地，那么也许需要更多时间让具有重要营养意义的底内无脊椎动物群落发展得与天然礁环境相似。
