Skeletal extension rate of the reef building coral <i>Porites</i>species from Aqaba and their environmental variables

Annual skeletal extension rates of the sclera-actinian corals Porites species were investigated in 32 colonies from the northern Gulf of Aqaba fringing reef at various depths (1 - 42 m). All corals reveal clear and regular skeletal density banding patterns. Results showed that the high-density annual growth bands were formed during winter and the low-density annual growth bands during summer. The mean annual extension rates of the studied corals reveal a large inter-colony variability with values ranged between 2.36 to 20.0 mm/year. While a general trend of decreasing coral extension rate with depth was observed and best explained by a simple exponential model, the rates clustered into two groups: 10.86 ± 2.54 mm/year in water depths less than 10 m, and 5.23 ± 1.99 mm/year below 12 m. Light intensity seems to be the primary environmental factor responsible for decreasing coral extension rate with depth since the effect of other environmental parameters could be neglected from the Gulf of Aqaba. Time series record of the mean annual coral extension rate showed a slight increasing linear trend which could be linked to increase seawater temperature over the period of time represented.

Fish assemblages in seagrass habitat along the Jordanian coast of the Gulf of Aqaba

The spatial distribution and community structure of the fishes were studied at different depths and sites along the Jordanian coast in seagrass habitat. A total of 37,034 fishes were counted representing 132 species belonging to 35 families observed during visual census in three sites (average of 4741.6 fish per transect). Out of the 132 species encountered, 5 species of them including Neopomacentrus miryae Lethrinus borbonicus, Pseudanthias squamipinnis, Lethrinus variegatus, Siganus rivulatus accounted for 57.7% of all individuals. Fishes were most abundant and significantly higher at 12 m depths (mean N = 2889.6) in comparison with shallow 6m depth (mean = 1225.3 with (p = 0.0218). This may be attributed to many plank-tivorous fishes that inhabit this depth such as P. squampinnis, Paracheilinus octotaenia, Chromis pelloura, Decapterus macarellus, and Cirrhilabrus rubriventralis probably with high abundance of plankton at 12 m depth than 6 m. The number of species was significantly higher in Phosphate Loading Berth (PLB;mean S = 54.7) than in Hotels area site (HA;mean S = 12.8) with (p = 0.0002) and Tala Bay site (TB;mean S = 31) with (p = 0.0484). This may be due to higher hard coral cover at Phophate Loading Berth.

Levels of Heavy Metals in Fishes (Cheilinus trilobatus) from the Gulf of Aqaba, Jordan

Heavy metal concentrations of Ni, Mg, Co, Cr, Cd and Cu were investigatedusing flame Atomic Absorption Spectrophotometer (AAS) in the liver, kidney, muscle, scale, gonad, gill and stomach of Cheilinus trilobatus fish species from the northern Gulf of Aqaba. Cheilinus trilobatus fish species were collected during the period May to August 2013. The results indicated significant differences between different organs of Cheilinus trilobatus for Ni (p = 0.0002), Fe (p = 0.0213), Co (p p Cheilinus trilobatus and its length. The levels of metal concentration of the present study were generally lower or within the ranges of those found in the fish of the Red Sea. After all, Cheilinus trilobatus fish species was found to be safe for consumption and do not pose a significant threat to the health of human consumers.

Integrated biological control of water hyacinths, Eichhornia crassipes by a novel combination of grass carp, Ctenopharyngodon idella (Valenciennes, 1844), and the weevil, Neochetina spp.

The efficacy of grass carp Ctenopharyngodon idella （Cyprinidae） and weevils Neochetina spp. （Curculionidae） to control the aquatic weed, water hyacinth, is investigated in a square net cage （happas） setting at a farm in Cuddalore District, South India. This novel combination of insects and fish is found to be superior to individual treatments for controlling the weed growth within ll0 d. The biomass of the weed, number of plants, percentage of flowered plants and chlorophyll contents were studied. The weed biomass is reduced from 5 kg （day 1） to 0.33 kg （day 110） when exposed to grass carp and weevils. The number of plants is reduced to 0.75 in grass carp and weevil exposed happas, while it is 741.5 in the control. The mean number of leaves per plant is also reduced. In addition, the chlorophyll a and b are significantly reduced in happas exposed to the combination of fish and insects when compared to the other treatments. Based on the results of this study, we consider the combined use of grass carp and weevils to be more efficient and sustainable for managing water hyacinths than the use of these organisms individually.

New Discovery of Coral Rubbings in the North-Western Gulf of Kachchh, Gujarat, Western India-GIS Based Evaluation

The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for economic reasons in connection with its proximity to the oil exporting countries of the Middle East. Besides, new coral rubbings were sighted in Jakhau, north-western Gulf of Kachchh. Dredging in Mandvi of the north Gulf covering 3.5 km2 revealed a similar assortment of live corals with their associated flora and fauna. These pioneering observations demonstrate that there exist live corals of young polyps-colony of Favia sp. belonging to the family Faviidae in the north-western Gulf of Kachchh. The environmental parameters there were carefully recorded as: surface water temperature (℃) varying from 29 to 31.8, salinity (ppt), pH, dissolved oxygen (mgL-1) and total suspended solids (mgL-1) in the ranges of 37- 43.5, 7.7- 8.45, 5.4 - 6.8 and 11- 31, respectively.

Calcium Composition and Microstructure of Coral Stylophora pistillata under Phosphate Pollution Stress in the Gulf of Aqaba

Corals and coral-reef ecosystems have been known to be extremely sensitive to environmental pollution, which effects on growth and calcification of their skeletons. Diffused phosphate dust during loading and shipment in seawater was found to cause serious impacts on corals by inhibiting calcification in their skeletons. Calcium concentrations in cultured fragments of coral Stylophora pistillata from Phosphate Terminal (PT) site in the Jordanian Gulf of Aqaba were investigated and compared with fragments from the same colony cultured in the Marine Science Station (MSS) site as marine protected area. Energy Disperse X-rays (EDX) spectroscopy and Scanning Electron Microscopy (SEM) were employed to determine the elemental composition of coral fragments and identify their microstructural characteristics, respectively. EDX results showed that coral samples from the Phosphate Terminal (PT) site were poorly mineralized with significantly low concentrations of calcium which were only about 12% of those from the MSS control site. Moreover, higher amounts of O and C in the elemental analysis of corals from the PT site indicated domination of organic matrix content in their skeleton which is typical for corals under phosphate pollution stress. This result was in accordance with the SEM images of the PT samples which exhibited alteration in their microstructure morphology resembling organic matrix as a major constituent, unlike the SEM images from the MSS protected area. These results strongly suggest that phosphate dust which is diffused during exportation through loading and shipping in the Gulf of Aqaba has adverse impacts on corals and marine ecosystem through decreasing calcium mineralization in their skeletons.

Heterogeneous Microstructure and Distribution of Trace Elements in Coral Stylophora pistillata Nursed in the Phosphate Loading Berth Site in the Gulf of Aqaba

Cultured Stylophora pistillata in Phosphate Loading Berth (PLB) sites in the Jordanian Gulf of Aqaba was investigated using Back-Scatter Scanning Electron (BSE) microscopy and Energy-Disperse X-ray (EDX) to determine trace elements and calcium concentrations’ distribution within the micrometer scale. Ca, C, and O in addition to six trace elements (Mg, Sr, S, Cl, Ni, and Na) were mapped within the sample cross section. Samples from the PLB were as expected poorly mineralized as previously reported and showed mineralization heterogeneity in the micrometer length scale in the BSE image. In four selected positions within the cross sections, Ca concentration found to range between 0.44 - 1.80 wt% in low-mineralized regions and between 3.99 - 4.66 wt% in mineralized regions. The average calcium concentrations were in accordance to previous study;about 10% of the Ca existed in the same coral species from other coastal sites in the Gulf of Aqaba. This could be attributed to the role of phosphate in inhibition of calcification and enhancement of photosynthesis. Amounts of trace elements in lower Ca concentration positions within the cross section were relatively very low except for chlorine, whereas positions with higher Ca contained amounts of Na and Sr. This study reports remarkable heterogeneity in mineral distribution within the microstructure of the coral Stylophora pistillata under phosphate pollution stress.

Limited proteomic response in the marine snail Melarhaphe neritoides after long-term emersion

Rocky intertidal organisms are commonly exposed to environmental gradients, promoting adapta-tions to these conditions. Emersion time varies along the intertidal range and in the supralittoralzone is frequently larger than a single tidal cycle, even lasting for weeks. The planktonic-dispersinggastropod Melarhaphe neritoides is a common species of the high shore, adapted to reduce waterloss in order to survive during long-term emersion. In this study, we investigated the molecular re-sponse, at the proteome level, of M. neritoides collected in high-shore tide pools to a series ofemersion periods, from 8 to 24 days, in laboratory conditions. We compared this response to indi-viduals maintained submerged during this period, because this was their original habitat. We alsoincluded a reversion treatment in the study, in which emersed individuals were returned to the sub-merged conditions. Although we detected an increase in overall protein concentration with longeremersion periods, contrary to general expectation, the two dimensional electrophoresis （2DE）-based proteomic analysis did not show significant differences between the treatments at the levelof individual protein spots, even after an emersion period of 24 days. Our results suggest that themetabolism remains unaltered independent of the treatment carried out or the changes are verysubtle and therefore difficult to detect with our experimental design. We conclude that M. neri-toides could be equally adapted to emersion and submersion without drastic physiologicalchanges.