Integrated Field Studies and Remote Sensing Approach for Mapping Seagrasses and Mangrove habitats, Red Sea, Egypt.

Abstract

The present work aimed to study the floristic composition, vegetation analysis, distribution of seagrasses and their relationship with sediment type in Red Sea. Forty stands of seagrass beds distributed in 4 sites located at Hurghada and Safaga Harbors were investigated. Five seagrasses were identified in the 40 stands; Halophila stipulacea (Forssk.) Asch., Halodule uninervis (Forssk.) Boiss., Halophila ovals (R.Br.) Hook. f., Thalassodendron ciliatum (Forssk.) Hartog and Syringodium isoetifolium (Forssk.) Hartog. All recorded seagrasses are belonging to tropical indo-pacific bioregion. Application of TWINSPAN and DECORANA, as classification and ordination techniques to the 40 stands resulted in five vegetation groups. Sediment of the investigated stands mainly constructed from fine sand. In addition, the correlation coefficient matrix showed that H. uninervis and H. ovalis prefer presence in sandy sediments, but Th. ciliatum positively correlated to total organic matter. On the other hand, H. stipulacea positively correlated with carbonates. These results are significant as a data base for management and conservation. Recent techniques as remote sensing integrated with field survey is recommended for monitoring these communities to give a clear view on spatial distribution of seagrasses on a large scale along Red Sea.