BENTHIC FORAMINIFERA OF THE WESTERN GULF OF MAINE 60 YEARS LATER: A PILOT STUDY COMPARING CHANGES IN SPECIES DISTRIBUTIONS

Abstract

Research Article| July 01, 2014 BENTHIC FORAMINIFERA OF THE WESTERN GULF OF MAINE 60 YEARS LATER: A PILOT STUDY COMPARING CHANGES IN SPECIES DISTRIBUTIONS Stephen A. Nathan; Stephen A. Nathan 4 1Department of Environmental Earth Science, Eastern Connecticut State University, Willimantic, CT 06226, USA 4Correspondence author. E-mail: nathans@easternct.edu Search for other works by this author on: GSW Google Scholar R. Mark Leckie; R. Mark Leckie 2Department of Geosciences, 611 N. Pleasant St., University of Massachusetts, Amherst, MA 01003, USA Search for other works by this author on: GSW Google Scholar Stephen B. Mabee Stephen B. Mabee 3Massachusetts Geological Survey, 611 N. Pleasant St., University of Massachusetts, Amherst, MA 01003, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Stephen A. Nathan 4 1Department of Environmental Earth Science, Eastern Connecticut State University, Willimantic, CT 06226, USA R. Mark Leckie 2Department of Geosciences, 611 N. Pleasant St., University of Massachusetts, Amherst, MA 01003, USA Stephen B. Mabee 3Massachusetts Geological Survey, 611 N. Pleasant St., University of Massachusetts, Amherst, MA 01003, USA 4Correspondence author. E-mail: nathans@easternct.edu Publisher: Cushman Foundation for Foraminiferal Research Received: 13 Jun 2013 Accepted: 30 Mar 2014 First Online: 03 Mar 2017 Online ISSN: 1943-264X Print ISSN: 0096-1191 © 2014 Cushman Foundation for Foraminiferal Research Journal of Foraminiferal Research (2014) 44 (3): 230–254. https://doi.org/10.2113/gsjfr.44.3.230 Article history Received: 13 Jun 2013 Accepted: 30 Mar 2014 First Online: 03 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Stephen A. Nathan, R. Mark Leckie, Stephen B. Mabee; BENTHIC FORAMINIFERA OF THE WESTERN GULF OF MAINE 60 YEARS LATER: A PILOT STUDY COMPARING CHANGES IN SPECIES DISTRIBUTIONS. Journal of Foraminiferal Research 2014;; 44 (3): 230–254. doi: https://doi.org/10.2113/gsjfr.44.3.230 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyJournal of Foraminiferal Research Search Advanced Search Abstract The Merrimack River paleodelta formed during the late Pleistocene as post-glacial rebound produced a local low stand in sea level. Subsequent sea-level rise drowned and eroded the paleodelta, which is now reworked by a variety of processes. This study used benthic foraminifera as a biotic and environmental proxy to evaluate the sand and gravel resources of the paleodelta.Nineteen box-core sediment samples were collected from the paleodelta along two east–west depth transects east of the Merrimack River mouth and off Plum Island, Massachusetts. From these samples, 62 species of benthic foraminifera were identified. When compared with distribution studies published over 60 years ago, some species have shifted landward in their distributions (e.g., Adercotryma glomeratum, Cibicides lobatulus, Reophax curtus, Trochammina squamata), while a few exhibited wider and more distal occurrences (e.g., Elphidium excavatum and Elphidium subarcticum). These differences point to variations in the Merrimack River outflow and its effects upon water column nutrient delivery, productivity, and organic matter flux over the past six decades. Other mitigating factors affecting benthic foraminiferal distributions may include increased seafloor disturbance from strong winter storms or fishing activity.Species richness and evenness peak at the delta break, coincident with low species dominance at about the 50-m depth. Q-mode cluster analyses show three distinct assemblages: “shallow” (≤30-m water depth), “deep” (≥40 m), and “delta edge” (~50 m). There are no apparent correlations between foraminiferal distributions and deltaic bedforms or sediment type. This implies that foraminiferal distributions are controlled by environmental variables other than grain size, such as food availability. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.