A Natural Phosphate Source for Lake Waccamaw, North Carolina, USA

Abstract

A limestone outcrop along the north shore of Lake Waccamnw, North Carolina, is foiind to cont.airi ca. 0.1 yo phosphate by weight,. Weathering proc s have probably driven steady inputs of phosphate from this soiircc throughout the lake's history, iLccounting for its near eutrophic state. The sediments of 1,iike \\'iiccimaw are enriched with phosphate, particnlarly in the littoral zone near the outcrop. Chemicd and biological processes apparently remove phosphate from solution rapidly, making detection of it soluhlc phosphate signal near the outcrop difficiilt. Managemcnt of niitricnt inputs and wrtcr qnality in Lake \Vl'ucciunaw requires consideration of the effects of this in-lake source of phosphate. Other sources of phosphate, partjicularly in the lake's drainiige basin, niity be less important than previously thonght.

Can suspension feeding by bivalves regulate phytoplankton biomass in Lake Waccamaw, North Carolina?

“…D .E .M ., 1983, 1989Owen, 1990) . Mesotrophic status and low chlorophyll a have been maintained despite nutrient loading from adjacent residential areas, development within the lake's drainage basin (Creager, 1984), and phosphate leaching from a limestone outcrop along the lake's north shore with associated nitrogen fixation (Cahoon et al ., 1990 ;Cahoon & Kucklick, 1993) . Light penetration through Lake Waccamaw's shallow water column is sufficient to support benthic macrophytes throughout the lake's basin (Stager & Cahoon, 1992) .…”

Parasites of the Carolina Bay Lake-EndemicFundulus waccamensis(Waccamaw Killifish)

“…The modern Lake Waccamaw is estimated to have formed between 15,000 and 32,000 years BP (Stager and Cahoon 1987) and comprises the headwaters of the Waccamaw River, which drains into the Atlantic Ocean at Winyah Bay, SC. Lake Waccamaw has an unusual water chemistry that diverges from most other Carolina bay lakes in having near-neutral pH, and high alkalinity, calcium concentration, and primary productivity (Cahoon et al 1990, Frey 1949, Stager and Cahoon 1987. The lake is the only one of its type that supports a rich endemic fauna of invertebrates and fishes (Casterlin et al 1984, Dillon et al 2013, Frey, 1951, Fuller 1977, Glover and Floyd 2004, Hubbs and Raney 1946, Porter 1985, Stager and Cahoon 1987.…”