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vol-36Distribution and status of seagrass beds around Hurghada area,
Red sea, Egypt
Eslam Osama, Abdel Kader M. Hassan and Mohamed M. Abou Zaid
Marine Biology & Ichthyology Section, Zoology Department, Faculty of Science,
Al-Azhar University, Cairo, Egypt.
Email: [email protected]
Received 22nd August 2010, Accepted 26th October 2010
Abstract
The present work includes the results of a field survey conducted to investigate the distribution and status of
the seagrass beds on the coastal area facing Hurghada city along the Egyptian Red Sea coast during the period from
April to May 2007. The surveyed area was about 40 km2
and located between 27° 30̀ 482ً E 33° 75̀ 4839º N
and 27° 08̀ 8756ً E 33° 85̀ 5422ً N. The results of the survey indicated that seagrass beds in this area were in a
form of monospecific (3 Locations) or mixed beds (9 Locations) ranged between 0.5 to about 15 m deep. In
addition, only seven species of seagrasses were recorded in the area. Seagrass coverage also showed wide range
between 50% at South Hurghada to 85% in most studied locations. The average biomass of seagrasses in the studied
locations ranged between 9.1 gdwm-2
at Northern shoreline site to 458.6 gdwm-2 at the offshore islands sites. Results
of mechanical soil analysis indicated that, seagrasses grow preferably in bottom sediment containing high amount of
sand and also sometimes silt with low gravels and clay percentages in soil structure. A comparison has made
between using the supervised and unsupervised classification of the satellite images for the determination of the
distribution of seagrasses beds in the area. The matching of the data obtained from the survey to the image analysis
indicated that unsupervised classification was the most accurate method especially during high number of shades to
predict the seagrass beds around Hurghada. Unsupervised classification indicates that the seagrass bed sizes
valuated by about 1.96 km2 mainly located offshore around Abo Monkar and Gifton islands.
