الملخص الإنجليزي
Marine artificial reefs (ARs) are structures that are submerged in the ocean to restore
and provide habitats for marine organisms, increase fish populations and biodiversity.
The species richness and composition are critical criteria for ecosystem functioning
and stability, and there is an urgent need to preserve marine biodiversity by protecting
and restoring reef habitats. This study assessed whether ARs successfully enhance
fisheries productivity using both fisheries-dependent and independent survey
methods, and investigated the impacts of physio-chemical parameters on the fish
communities at Suhar, Sea of Oman, Sultanate of Oman. The study sites were selected
based on age (old, middle and young) and depth (shallow, deep) categories. To
characterize fish communities at ARs, sites, fisheries-independent methods included
diver operated stereo-video (DOVs) and Baited Remote Underwater stereo‐video
(BRUVs), while the fisheries-dependent method involved deploying fish traps to
assess fish communities abundance and biomass. Environmental parameters
(temperature, salinity, dissolved oxygen) were collected. The shallow (11 - 13 m) and
old (~ 20 years old) ARs sites had higher catch per unit effort (CPUE) than the nearby
deep natural reefs (20 - 22 m) and middle-aged (~15 years old) sites, indicating that
ARs enhance fisheries productivity in this area. The highest number of individuals
were found on shallow and deep ARs in both summer and winter surveys. The non metric multi-dimensional scaling (NMDS) analyses showed that the fish assemblages
of ARs sites were different from nearby natural reef sites. Lutjanus lutjanus )> 19cm)
was one of the most common important fisheries species, which was abundant on
deeper ARs. The Lutjanidae family were the most abundant family recorded in fish
traps and the DOVs surveys. However, Carangidae was the most abundant family
observed in BRUVs surveys, as they are highly mobile, and bait attracted. These
results highlight the importance of using different methods to monitor ARs. Depth
was a key factor in the difference in physico-chemical parameters between both
seasons. Depth was highly correlated with species evenness and dissolved oxygen in
winter. This study illustrates that ARs enhance fisheries productivity in the Suhar
region. However, the mature ARs will enhance the fish productivity in compare to
young ARs.
