Infaunal Marsh Foraminifera From the Outer Banks, North Carolina, USA

The distribution and abundance of live (rose Bengal stained) and dead, shallow infaunal (0–1 cm depth) and deep infaunal (>1 cm depth) benthic foraminifera have been documented at three locations representing different salinity settings on the fringing marshes along the Pamlico Sound and Currituck Sound coasts of North Carolina’s Outer Banks. Two cores taken at each site represent the lower and higher marsh. Twenty-two taxa were recorded as live. Of these, eight taxa were found only at shallow infaunal depths; the other 14 taxa occur at deep infaunal depths in one or more cores. Only Jadammina macrescens and Tiphotrocha comprimata were recorded as living in all six cores. The distributions of the other taxa were restricted by combinations of infaunal depth, salinity regime and location on the marsh. The tests of infaunal foraminifera were generally more likely to be preserved in the lower marsh than the higher marsh at lowand intermediate-salinity sites. The opposite pattern was evident at the high-salinity site but this may be due to the low numbers of deep infaunal specimens recovered. Arenoparrella mexicana, Haplophragmoides wilberti, Jadammina macrescens and Trochammina inflata are the most resistant taxa, whereas Miliammina fusca is the species whose tests are most likely to be lost to post-mortem degradation. In five of the six cores, foraminiferal assemblages and populations do not differ significantly with depth which suggests that the foraminifera of the 0–1 cm depth interval provide an adequate model upon which paleoenvironmental (including former sea level) reconstructions can be based. Comments Published in Journal of Foraminiferal Research, Volume 35, Number 2, April 2005, pages 148–170. This journal article is available at ScholarlyCommons: http://repository.upenn.edu/ees_papers/48 J(!urr~nl of I.i,~-cr~~rirt~ft~~a/ Research, v. 35, no. 2. p. 148-170. April 2005 INFAUNAL MARSH FORAMINIFERA FROM T H E OUTER BANKS, NORTH CAROLINA, U.S.A. STEPHEN J . CULVER' AND BENJAMIN l? HORTON~ AIBSTRACT North Carolina. The deepest records of living marsh foraThe distribution and abundance of live (rose Ben[,-lI stained) and dead. shallow infaunal (0-1 cm depth) and deep infaunal (>1 cm depth) benthic foraminifera have been documented ;rt three locations representing different salinity settings on the fringing marshes along the Pamlico sound' and Currituck Sound coasts of North Carolina's Outer Banks. Two cores taken a t each site represent the lowcr. and higher marsh. Twenty-two tax;! were recorded as live. Of these, eight h x a were found only a t shallow infaunal depths; the other 14 taxa occur at deep infaunal depths in one or more cores. Only Jadammina ntacrescerts and Tipholrocha compriinata were recorded as living in all six cores. The distributions of the other taxa were restricted by combinations of irrfaunal depth, salinity regime and location on the marsh. The tests of infar~nal foraminifera were generally more likely to be preserved in the lower marsh than the higher rrlarsh at lowan11 intermediate-salinity sites. The opposite pattern was evident at the high-salinity site bat this may be due lo the low numbers of deep infaunal specimens recovered. Arenol~arrella mexicanq [laplopltragmoides wilberti, Jadammina macrescens and Trocharnmina irijlatn are the most resistant taxa, whereas Miliammirla Jusctc is the species whose tests are most likely to be lost to post-mortem degradation. In five of the six cores, foraminifera1 assemblages and populations do not difrer signilicantly with depth which suggests that the foraminifera of the 0-1 cm depth interval provide an adequate model upon which paleoenvironmental (including former s~ level) reconstr~~ctions can be based.