How does macrofaunal bioturbation influence the vertical distribution of living benthic foraminifera?

Marine Ecology Progress Series

Thomas Gestin¹  Jean-Claude Duchêne¹  Olivier Maire¹  Emmanuelle Geslin¹  Alicia Romero-Ramirez¹  Christine Barras¹  Maria-Pia Nardelli¹ 

关键词: Foraminifera;    Ammonia tepida;    Bioturbation;    Anoxia;    Locomotion activity;    Vertical distribution;   

DOI  :  10.3354/meps11929

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

ABSTRACT: The vertical distribution of benthic foraminifera in coastal sediments seems tightly controlled by bioturbation processes. However, it still remains unclear whether living specimens found at depth around biogenic structures actively migrated from the sediment surface to reach oxygenated food-rich micro-environments or have been passively transported by macrobenthic organisms. The present study experimentally demonstrates that the vertical distribution of Ammonia tepida, one of the dominant species of foraminiferal assemblages in temperate intertidal mudflats, is tightly dependent on macrofaunal bioturbation modes and rates. The high degree of similarity between vertical profiles of foraminifera and inert particle tracers revealed that this species is not able to (1) efficiently resist biologically induced downward transport and (2) initiate rapid upward migrations to the oxic zone. The strong decrease of locomotion activity recorded in anoxic conditions suggests that encystment and inactivity are the first strategic responses to sudden oxygen depletion.

【 授权许可】

Unknown