Collapse of Holocene mangrove ecosystems along the coastline of Oman

Sedimentological, geochemical, and paleontological investigations of the coastline of northeastern Oman have provided the authors with an in-depth insight into Holocene sea levels and climate conditions. The spatial distribution and species assemblage of mangrove ecosystems are analyzed. These ecosystems are sensitive to changes in sea level and precipitation and thus reflect ecological conditions. The close proximity to archaeological sites allows us to draw conclusions regarding human interaction with the mangrove ecosystems. Our interdisciplinary inquiry reveals that the mangrove ecosystems along the east coast of Oman collapsed ~6000 cal yr BP on a decadal scale. There is no sedimentological evidence for a mid-Holocene sea-level highstand. The ecosystem collapse was not caused by sea-level variation or anthropogenic interferences; rather, it was the consequence of reduced precipitation values related to a southward shift of the Intertropical Convergence Zone. This resulted in a decrease of freshwater input and an increase in soil salinity. Further, the aridification of the area caused increased deflation and silting up of the lagoons.