Bathymetric and Environmentally Influenced Patterns of Carbonate Sediment Accumulation in Three Contrasting Reef Settings, Danjugan Island, Philippines

Abstract

Abstract This study assesses patterns of biogenic carbonate sediment production associated with three different reef and reef-related settings at Danjugan Island in the Philippines. Sediments were collected along transects on windward and leeward sides of the island (1–28-m depth) and from a semirestricted lagoon (1.5–2.5-m depth). Sediment assemblages from all sites are dominated (in decreasing order of abundance) by coral (29.1%), Halimeda (28.8%), mollusks (13.5%), and benthic foraminifera (10.2%). Sediments from windward sites are dominated by fragments of corals (15.0–42.5%), Halimeda (14.0–32.1%), mollusks (8.5–21.6%), and benthic foraminifera (7.8–32.9%). Bryozoans represent a significant secondary component (2.77–14.6%). Leeward sediments primarily comprise coral, Halimeda, and molluscan grains, although are characterized by a higher abundance of Halimeda (29.7–49.2%) than the windward transect. Lagoon sediments comprise primarily coral (1.3–42.7%) and Halimeda (13.8–37.2%) in the outer lagoon, bu...