2Author for correspondence: e-mail email@example.com.
TEMPERATURE THRESHOLD AS A BIOGEOGRAPHIC BARRIER IN NORTHERN INDIAN OCEAN MACROALGAE1
Version of Record online: 8 JUN 2006
Journal of Phycology
Volume 42, Issue 4, pages 749–756, August 2006
How to Cite
Schils, T. and Wilson, S. C. (2006), TEMPERATURE THRESHOLD AS A BIOGEOGRAPHIC BARRIER IN NORTHERN INDIAN OCEAN MACROALGAE. Journal of Phycology, 42: 749–756. doi: 10.1111/j.1529-8817.2006.00242.x
1Received 1 November 2005. Accepted 25 April 2006
- Issue online: 8 JUN 2006
- Version of Record online: 8 JUN 2006
- Arabian seas;
- biotic turnover;
- Indian ocean;
- sea-surface temperature;
- temperature limit;
The most eastern point of the Arabian Peninsula, Ras Al Hadd, marks the boundary between the Arabian Sea and the Gulf of Oman. This geographic landmark coincides with an abrupt floristic turnover, probably one of the sharpest biotic transitions known in marine biogeography. The floras of different Arabian localities across this floristic break were compared using macrophyte distribution data throughout the Indian Ocean and seasonal sea-surface temperature (SST) data. The localities from the Arabian Gulf and Gulf of Oman differ significantly from those of the Arabian Sea based on their species richness, species composition, average distribution range per species, general temperature affinity of the composing species, and seasonal temperature data of the coastal waters. Pooling the temperature data into two groups (SST3avg, average SST of the three warmest seasons; SSTmin, minimum of the seasonal SSTs) revealed a temperature limit at 28°C using both the temperature affinity data of the floras and the seasonal temperatures recorded for the specific Arabian localities, which significantly separates the Arabian Sea from localities of both Gulfs. Finally, SST data of the Indian Ocean were analyzed using this upper temperature threshold of macrophytes at 28°C and the lower temperature limit of corals at 25°C, revealing general macrophyte diversity patterns.