Evaluation of structural properties of Baghdad-Baquba road pavements

Structural evaluation of the road pavements is an essential concept to ensure their efficiency to carry traffic loads and to archive the data for future usage especially in major highways. Baghdad-Baquba is an important interstate highway as it connects the capital of Iraq with Diyala governorate which is one of the biggest governorates in Iraq. In addition, this highway connects Baghdad city with several governorates in the north of Iraq. However, this highway exhibits low serviceability due to poor condition of its pavements. Therefore, the structure of the pavements must be evaluated to specify the causes those lead to the decrease in its serviceability and to propose the suitable rehabilitation methods. This study aims to adopt a field survey to extract a number of samples from selected section in this highway to evaluate the structural properties of the pavements based on laboratory testing. Four cores and one pit with 1×1 m dimensions were extracted from the pavements in the field. Several tests were implemented on these tests based on standard methods. The results of the tests were adopted to evaluate the capacity of the pavement based on AASHTO 1993 method. The results exhibited that the estimated applied traffic load exceeded the calculated allowable traffic load by more than 12 times which reflect the disastrous situation. Therefore, the study proposed to rehabilitate the pavements by reconstruction. The study proposed to construct three layers: asphaltic layer with thickness of 240 mm, granular base with thickness of 250 mm, and granular subbase with a thickness of 250 mm. The study stated that all layers must have superior quality with high elastic modulus to resist the predicated traffic load

Genetic population structure of the blue sea star (<i>Linckia laevigata</i>) and the boring giant clam (<i>Tridacna crocea</i>) across Malaysia

Various studies on population genetics in the Indo-Pacific that include the Coral Triangle region have revealed phylogeographic patterns in marine species populations. However, little is known about the population structure and connectivity pattern among the coral reefs in four seas surrounding Malaysia: the Strait of Malacca (Andaman Sea), the South China Sea, the Sulu Sea, and the Sulawesi Sea. In view of this, we examined the genetic population structure of two invertebrate species: the blue sea star (Linckia laevigata) and the boring clam (Tridacna crocea) from seven localities across Malaysia, including Pulau Layang-Layang in the Spratly Islands. Additional samples of L. laevigata were obtained from the Davao Gulf, the Philippines. The analyses were based on partial mitochondrial cytochrome oxidase I sequences of L. laevigata and T. crocea. Populations of L. laevigata and T. crocea showed departure from neutrality, indicating selection or population expansion. However, a mismatch analysis suggested population expansion. Lack of genetic population structure in L. laevigata (ΦST = − 0.001, P = 0.399) implies high connectivity among the sampled reef sites. There was subtle genetic structuring in populations of T. crocea (ΦST = 0.032, P = 0.009), but AMOVA did not detect any structure in the a priori groupings. The genetic population structure and scale in connectivity are most likely attributed to the life history traits of the sea star and giant clam species, and also to the geological history and seasonal current patterns of the region

Phylogenetic relationships and revision of the genus Blastomussa (Cnidaria: Anthozoa: Scleractinia) with description of a new species

The Indo-Pacific coral genus Blastomussa (Cnidaria: Anthozoa: Scleractinia) includes three species, i.e., B. merleti, B. wellsi, and B. loyae. Following the re-examination of relevant type material, other museum specimens, and the study of newly sampled corals, the genus is revised and the new species B. vivida is described. The new species differs from its congeners by being encrusting, having coralla with a cerioid corallite arrangement and much larger corallites. In vivo, the expanded polyp mantle is fleshy and characterised by bright, vivid colours. Specimens were sampled in New Caledonia, northern Papua New Guinea, Sabah (northern Malaysia), Brunei Darussalam and the east coast of Peninsular Malaysia. Additional records from Southeast Asia and the western Pacific were obtained through the study of museum collections and published illustrations of living animals in situ: Japan, Vietnam, Indonesia, Philippines, and Australia. The new species appears widespread and has so far been misidentified as B. wellsi, which has smaller corallites, less septa, and a phaceloid corallite arrangement. The phylogenetic relationships within the genus Blastomussa and with other genera were investigated by analyses of their nuclear and mitochondrial DNA. These other genera are Parasimplastrea, Plerogyra, Physogyra, all currently incertae sedis in the Robust clade of Scleractinia as a result of molecular coral systematics, and Nemenzophyllia, whose phylogenetic position is examined for the first time. Representatives of all these genera are characterised by fleshy polyps with well-developed and expandable mantles. They are all closely related and form a strongly supported clade. The results of the molecular analyses provide evidence for Blastomussa's monophyly and show that the new B. vivida is a distinct species, which is most closely related to B. wellsi. Furthermore, the only known extant species of the genus Parasimplastrea appears to be embedded within the Blastomussa clade, thus prompting its taxonomic revision. Because Blastomussa is closely related to the monospecific Nemenzophyllia, the affinities of their polyp and corallite morphology are discussed. Although polyp morphology and molecular data suggest that Blastomussa, Plerogyra, Physogyra, and Nemenzophyllia could constitute a new scleractinian family, the macro and micromorphology of their skeletons need to be examined before a family diagnosis can be formulated

Size-dependent dispersal by Goniopora stokesi corals at Semporna, eastern Sabah, Malaysia

Free-living corals of Goniopora stokesi Milne Edwards & Haime, 1851 (Scleractinia: Poritidae) were observed at various sites during the Semporna Marine Ecological Expedition(SMEE 2010) in eastern Sabah, from 29 November to 18 December 2010. At two out of 63 sites, dense aggrega tions (75- 100% cover) with extended polyps had formed only on the sandy bottom of depressions (at 16-20 m depth). These corals could not leave, unlike scattered G. stokesi corals found on sandy slopes, which may migrate in downward direction (Hoeksema 1988). The largest coral patch (Fig. 1a) was c. 200 m2 (Denawan I.) and the other only c. 40 m2 (Larapan I.).Some colonies showed budding through the formation of polyp balls (Fig. 1b), which is a known trait in this species (Boschma 1923; Rosen and Taylor 1969). A few parent individuals had loose polyp balls around them, which had dropped and rolled to available space nearby. Most large specimens were dome-shaped with their dead, fl attened base on the sand or partly buried inside it (Fig. 1b). Only a few were found in upside-down position or laying on a side (Fig. 1c). The heavy weight and fl at underside of these large corals would likely hinder any further migration and may render them practically immobile. Our observations suggest that free-living G. stokesi corals can disperse easily when they are small and may eventually form dense fi elds when they are physically entrapped by the surrounding reef

Onset of autotomy in an attached Cycloseris coral

(Scleractinia: Fungiidae) are either complete individuals or fragments in various stages of fission and regeneration (Hoeksema and Waheed 2011). Their fragmentation is initiated by a process of radial skeleton dissolution called autotomy (Yamashiro et al. 1989; Yamashiro and Nishihira 1994). Only unattached fragmenting corals are known, representing the adult anthocyathus stage. The anthocaulus stage in which juveniles of free-living species are still attached, as i

Scleractinian corals (Fungiidae, Agariciidae and Euphylliidae) of Pulau Layang-Layang, Spratly Islands, with a note on Pavona maldivensis (Gardiner, 1905)

Layang-Layang is a small island part of an oceanic atoll in the Spratly Islands off Sabah, Malaysia. As the reef coral fauna in this part of the South China Sea is poorly known, a survey was carried out in 2013 to study the species composition of the scleractinian coral families Fungiidae, Agariciidae and Euphylliidae. A total of 56 species was recorded. The addition of three previously reported coral species brings the total to 59, consisting of 32 Fungiidae, 22 Agariciidae, and five Euphylliidae. Of these, 32 species are new records for Layang-Layang, which include five rarely reported species, i.e., the fungiids Lithophyllon ranjithi, Podabacia sinai, Sandalolitha boucheti, and the agariciids Leptoseris kalayaanensis and L. troglodyta. The coral fauna of Layang-Layang is poor compared to other areas in Sabah, which may be related to its recovery from a crown-of-thorns seastar outbreak in 2010, and its low habitat diversity, which is dominated by reef slopes consisting of steep outer walls. Based on integrative molecular and morphological analyses, a Pavona variety with small and extremely thin coralla was revealed as P. maldivensis. Since specimens from Sabah previously identified as P. maldivensis were found to belong to P. explanulata, the affinities and distinctions of P. maldivensis and P. explanulata are discussed