Seagrass Research Articles

CONDITIONS OF FORMING FOR THERAPEUTIC MUD IN THE VOEVODA BAY (AMUR BAY, JAPAN SEA)

The water dynamics and distribution of the sea grass Zostera marina are investigated as factors of the curative mud forming in the Voevoda Bay. The water currents are measured directly. The closed circulation is formed in the middle part of the bay by prevailing winds: anticyclonic by northwestern wind and cyclonic by southeastern wind. Zostera marina distribution is researched by divers. Its highest biomass is observed on the shallows where projective coating is 100 % and mean biomass is 3 kg/m 2 (wet weight). Bottom sediments and depth of the acoustic basement are mapped using seismoacoustic method. The maximal thickness of the curative mud layer is found in the internal part of the bay (Melkovodnaya Bight) where it reaches 15 meters.

Biocomposites of different lignocellulosic wastes for sustainable food packaging applications

Abstract The suitability of three local lignocellulosic wastes i.e. almond shell (AS), rice husk (RH) and seagrass (SG) as fillers in PHB/Fiber composites applications has been studied. PHB/Fiber composites with 10 phr and 20 phr fiber content were prepared by melt blending. The influence of the fiber type (size, morphology and origin) and content on the morphological, mechanical and thermal properties of the as obtained composites has been assessed. To evaluate the potential use in food packaging applications, the barrier performance to water, thermoforming ability and disintegration in controlled composting conditions of the composites were also studied. All the fibers have demonstrated to be apt for their use as fillers in PHB/Fiber composites, showing a reinforcing effect without affecting the crystallinity and the disintegration rate of PHB. The thermal stability and the water barrier performance of the composites were reduced by the presence of the fibers. Nevertheless, the addition of AS resulted in the best balance of properties, in terms of permeability and mechanical properties, finding an enhancement of the thermoforming ability of PHB when 10 phr of AS was added.

Elemental ratios and lipid classes in a coral reef food web under river influence

Coral reefs in the Caribbean and Gulf of Mexico are increasingly suffering from anthropogenic nutrient inputs principally from fertilizers as identified by their δ15N signatures. To determine if primary producers are passively affected by anthropogenic nitrogen enrichment in a coral reef community, carbon: nitrogen ratios (C:N mol mol−1) were measured. The C:N ratio was used as a proxy for nitrogen enrichment in primary producers when the ratio decreases, and for lipid plus carbohydrate in terms of C, and protein in terms of N in primary producers and consumers. Lipid classes and the triacylglycerol to sterol (TAG:ST) ratio were used to evaluate energy storage as an indication of nutritional quality in the six most abundant primary producers, and of nutritional condition in ten ubiquitous consumers in a coral reef in the Gulf of Mexico under river influence. A low C:N ratio revealed nitrogen enrichment in primary producers. Among the lipids, high TAG proportions were detected in phytoplankton and zooxanthellae suggesting that they have a higher nutritional quality in terms of energy, followed by sea grass, mangrove, and macroalgae. During the rainy season TAG:ST increased in primary consumers such as echinoderms, and top predators such as the perciform fish Bodianus rufus, Ocyurus chrysurus and Caranx hippos, suggesting an increase in energy storage. In contrast, TAG:ST decreased in the principal habitat providing coral Montastrea cavernosa, along with a decrease in the phospholipid proportion suggesting a poor nutritional condition. There were three species with no change in their TAG:ST ratio: the sponge Aplysina sp., the masked goby Coryphopterus personatus and the surgeon fish Achanturus chirurgus. The lower value of TAG, TAG:ST ratio and phospholipid proportion in the coral M. cavernosa suggests that the reported abundance of zooplankton does not satisfy the energy demand of M. cavernosa during the rainy season.

Elemental concentration and potential ecological risk assessment of reef associated surface sediments of Appa Island, Gulf of Mannar Biosphere Reserve, Southeast coast of India

Thirty three surface sediments were collected for the present study to assess the elemental concentration and its associated ecological risk in the reef associated surface sediments, Appa Island, Gulf of Mannar Biosphere Reserve, South east coast of India. The distribution of calcium carbonate in the reef sediments is controlled by coral debris and shell fragments whereas the Organic matter (OM) content are chiefly derived from mangroves and sea grasses. The circulation of trace elements and Fe, Mn are controlled by the fluvial process and re-suspended sediments. The concentration of Pb was primarily controlled by migration of pollutants through long shore sediment transport process. The main source of Pb in the study area is from coal incinerating power plants and coal handling operations from harbors.

PENGARUH KUALITAS AIR TERHADAP PRODUKSI RUMPUT LAUT (Kappaphycus alvarezii)

The study aims to determine the effect of water quality on the production of seaweed (Kappaphycus alvarezii). This study was an experimental study using a completely randomized design (CRD). There are three treatments, treatment A (50 m), treatment B (500 m), treatment C (1000 m) and a control consisting of three replications. The research variables were observed include the production and quality of the sea water. The analysis technique used in this research is the analysis of variance were processed using SPSS version 20. The results showed that the location most suitable planting sea grass is at a spacing of 500 meters from the river mouth to the value of the highest average production of 88500g (88,5kg ) while the water quality such as salinity, pH, temperature, turbidity, phosphates and dissolved oxygen, still within acceptable limits for the growth and production of seaweed (Kappaphycus alvarezii)

PERTUMBUHAN DAN PRODUKSI VARIETAS SELADA (Lactuca sativa L) PADA BERBAGAI DOSIS PUPUK ORGANIK RUMPUT LAUT

Lettuce (Lactuca sativa L.) is a widely known leave vegetable. This vegetable is so rich in nutrient contents particularly vitamins and minerals that people can consume it to meet their nutrient requirements. This study was aimed at assessing the effects of sea grass organic fertilizer administration on the growth and production of lettuce. The study was conducted at the trial farm of Department of Agrotechnology, Faculty of Agriculture, Djuanda University, Bogor from March to April 2014. A completely randomized design with two factors consisting of lettuce variety (V) and sea grass organic fertilizer (R) was used. The varieties of lettuce consisted of curly lettuce (Lactuca sativa var. New grand rapid) (V1) and red lettuce (Lactuca sativa var. new red fire) (V2). Sea grass organic fertilizer (R) was given in three levels, namely no fertilizer (R0), 500 kg/ha (0.5 recommended rate) (R1), 1000 kg/ha (1.0 recommended rate) (R2), 1500 kg/ha (1.5 recommended rate) (R3), and 2000 kg/ha (2.0 recommended rate) (R4). Keywords: lettuce variety, sea grass organic fertilizer, growth and production.

Rising Ocean Temperatures Threaten Carbon-Storing Sea Grass

A new model predicts that as ocean temperatures rise, carbon-storing sea grass may disappear and even go extinct in some ecosystems.

DIVERSITY OF BRITTLE STARS (OPHIUROIDEA) IN TALISE WATERS, NORTH SULAWESI

Talise waters, located in North Sulawesi, is one of many coastal areas in Indonesia with sea grass cover extending along the reef flat. This ecological feature is beneficial for living habitat of associated fauna, including brittle stars. Brittle stars are group of Echinodermata reported to be abundantly found in sea grass ecosystem. However, the diversity of this fauna is less reported except as part of echinoderm studies. This research aims to investigate the diversity of brittle stars in Talise waters. Data were collected in July 2009 applying quadrant transect method. In total of 650 individuals belonging to 4 families (Ophiotrichidae, Ophiodermatidae, Ophiocomidae and Ophiuridae) and 10 species were recorded during this study. The diversity (H’=1.58), richness (D=1.69) and Evennes Index (J=0.89) was relatively higher compared to adjacent water in North Sulawesi such as Wori (H =1.64, D =1.38, J=0.85), Kema (H =1.3, D =0.38, J=0.36) but lower than East Likupang waters (H =1.95, D =2.42, J=0.97). Keywords: brittle star, diversity, richness, evennes, Talise waters

Pressures and Status of Seagrass Ecosystem in the Coastal Areas of North Bintan, Indonesia

This study investigates the status and anthropogenic pressures on seagrass ecosystem. Urbanization and tourism in the coastal areas of Bintan, Indonesia were increasing in the recent years. They have become new pressures to intertidal ecosystem and habitats, particularly seagrass ecosystem. Seagrass meadows are the important ecosystem and habitats in Bintan region. They provide a wide range of ecosystem services, including for small-scale fisheries and have being Dugongs (Dugong dugon) habitats for food. Currently, the sea grass status is less healthy or damaged with 11 species. The anthropogenic disturbance processes have affected the spatial distribution, percent coverage, biodiversity, and community structure of sea grass. Moreover, several species are hard to find. Directly, sea grass meadows are impacted by introduced coastal development (i.e. settlement area, tourism accommodation, port, etc.), land-based pollution, reclamation, boating traffic, dredging activities and tourism activities. Sea grass conservation area and marine spatial planning based on the land- and seascape connectivity is important for conservation efforts and sustainable management of sea grass.

Diversity and antagonistic potential of bacteria isolated from marine grass Halodule uninervis

The aim of this study was to isolate bacteria from sea grass, Halodule uninervis collected from the coastal area of Jeddah, Saudi Arabia and to screen them for antifungal and enzymatic activities. We have isolated 162 rhizo and endophytic bacteria from soil, roots, and leaves of the sea grass. Antifungal screening of isolated bacteria revealed 19 strains (11.7%) capable to inhibit growth of four pathogenic fungi, Pythium ultimum, Phytophthora capsici, pyricularia oryzae, and Rhizoctonia solani in an in vitro assay. Taxonomic and phylogenetic analyses on the basis of 16S rRNA gene sequence revealed 97–99.9% sequence identity to recognized species. Bacillus, Staphylococcus, Jeotgalicoccus, and Planococcus, within the Phylum Firmicutes, Kocuria, Arthrobacter, Ornithinimicrobium and Corynebacterium (Actinobacteria), Sulfitobacter, Roseivivax, Ruegeria (α-Proteobacteria), Moraxella, and Vibrio (γ-Proteobacteria), were isolated. Strains belong to Phylum Firmicutes remain dominant antagonistic bacteria in this study. Further hydrolytic enzyme production was determined for these antagonistic bacteria. Our results demonstrated that the sea grass represents an important source of diverse antagonistic bacteria capable of producing antifungal metabolite.

Notes on two shallow water isopods (Crustacea: Peracarida: Isopoda: Idoteidae) from Kino Bay, Gulf of California, Mexico

Abstract Two species of isopods of the family Idoteidae were collected in the same sample, among sea grasses, in the northern Gulf of California, Mexico. The first species, Synidotea harfordi Benedict, 1897, was more abundant (46 specimens) than the second species, Eusymmerus antennatus Richardson, 1899 (eight specimens). Synidotea harfordi has previously been considered uncommon in the Gulf of California, and more like a component of warm-temperate to colder-water fauna. The male of E. antennatus has not been illustrated but SEM photographs are provided and show angular margins of the first three pereonites and a sharply bent lateral margin of the telson. Females also have angular first pereonites. All previous illustrations show rounded pereonites margins. Buccal appendages of E. antennatus are illustrated and compared with previous descriptions.

Occurrence of two sympatric species of Palaemonidae and Hippolytidae (Decapoda, Caridea) in a coastal ecosystem in western Mexico

AbstractOne species of Hippolytidae,Hippolyte californiensisHolmes, 1895, and one species of Palaemonidae,Periclimenes infraspinis(Rathbun, 1902), were collected in a single sample among sea grass in the northern Gulf of California, Mexico.Hippolyte californiensisis partly illustrated and compared to the descriptions available in the literature, noting minor differences with material from California where it was originally described. Diagnostic characters ofP. infraspinisare also illustrated. Sex proportion and size distribution indicate a higher incidence of females (male : female ratio, 1 : 2.59), smaller size in males, a strong incidence of ovigerous females (31%), and a brood clutch of 82-200 embryos inP. infraspinis. InH. californiensis, males were more abundant (1.41 : 1), the incidence of ovigerous females was low (15%), and females carried 51-115 embryos. In both species, males, females, and ovigerous females were significantly different in size. These two species have not been reported as sympatric.

Состав донных отложений приливо-отливной акватории (юго-западный район Татарского пролива)

Data on the carbon hydrates content and composition is given: aliphatic hydrocarbons and aromatic hydrocarbons in comparison with total organic matter, phyto/pigments and quantity of heterotrophic and oil-oxidizing bacteria in bottom sediments of the Toki River tide estuary (the Tatar Strait). It has been stated that substance/structural composition of the sedimentation material in the Toki River estuary is determined by two matter flows of opposite direction: terrigenous runoff with river waters (wood and grass remains, fresh water phyto- and bacteria-plankton, anthropogenous pollutants including aliphatic hydrocarbons and aromatic hydrocarbons) and materials of marine origin including mineral components (fine-dispersed sand fractions), died-off macrovegetations, sea grass phyto- and bacteria- plankton. Phyto-and bacteria-benthos communities well-adopted to variable conditions of salinity are developing in bottom sediments. High ability of the benthos microbe community to hydrocarbons utilization has been revealed. At the same time intermediate products of organic matter destruction (spirits and ethers) are found in the estuary bottom sediments micro/aerophilic conditions. Over the period from 2009 to 2016 a considerable increase of toxic aromatic hydrocarbons content in the Toki River internal estuary has been registered – a probable source of them is a solid waste dump located on the river catchment. According to group composition of н-alkanes molecular spectra, natural sources contribute the most in formation of the current bio/geo/chemical background of the smaller estuary.

Разработка технологии сухого концентрата напитка на основе пектина из морской травы Phyllospadix iwatensis с добавлением экстракта элеутерококка Eleutherococcus senticosus

Разработка технологии сухого концентрата напитка на основе пектина из морской травы Phyllospadix iwatensis с добавлением экстракта элеутерококка Eleutherococcus senticosus

PLA based biocomposites reinforced with Posidonia oceanica leaves

Abstract Biocomposites can valorize some natural products related to natural processes or crop and waste industries. In this work, leaves of Posidonia oceanica (PO), dominant sea grass in the Mediterranean Sea, were used to prepare PLA based biocomposites. Materials were prepared by melt mixing PLA with PO as filler. The morphology as well as the mechanical and thermal properties of PLA/PO composites were evaluated and related with the influence of the content and size of PO. Moreover, the experimental elastic moduli of the biocomposites was modelled employing the Halpin–Tsai (HT) model. Furthermore, in order to take into consideration the high porosity of PO leaves, the HT parameters related to the density of PO were evaluated by estimating the % of PO filled by PLA. The results highlighted that the use of PO leaves as filler influenced all the investigated properties. In particular, by increasing the PO content, both tensile and flexural moduli increased. While, on the contrary, both tensile and flexural strengths of the biocomposites decreased if compared with neat PLA. Finally, the method to determine the parameters for the HT model was found to be able to give a good evaluation of tensile modulus of the composites, for all the filler content and size.

Seagrass Community At Kampung Ambong’s Water East Likupang Subdistrict, North Minahasa Regency

This Research is done at Kampung Ambong’s Water East Likupang Subdistrict, North Minahasa Regency. The aim of this research is to know the type composition of seagrass and to analyzed soliding, dominatting index, various index, index of spreadness. The data taken with the line transect method. The transect placement divided become 3 transect line that located it uphold straight of beach line each of them 95 meter long. Meanwhile the space between one transect to another (second and third) each 100 m.Meanwhile the space between one transect to another (second and third) each 100 m. All of them identified as : Cymodocea rotundata, Syringodium isoetifolium, Halophila decipiens, Halodule pinifolia, Cymodocea serrulata, Enhalus acoroides, Halphila minor, Thalassia hempricii, Halodule uninervis, Halophila spinulosa. From the soliding each species show the highest score which is Cymodocea rotundata 2608 individu/m2, Syringodium isoetifolium 816 individu/m2, Halophila decipiens 420 individu/m2, Halodule pinifolia 292 individu/m2, Cymodocea serrulata 268 individu/m2, Enhalus acoroides 260 individu/m2, Halophila minor 224 individu/m2, Thalassia hempricii 160 individu/m2, Halodule uninervis 124 individu/m2, Halophila spinulosa 20 individu/m2.Whereas dominatting index be obtained 0.3 be in low category. its mean there is no species that to dominate in that water. Various index be obtained 1.65 be in mid category. it show that species community almost in spread condition, because it has the same opportunity.Index of spreadness be obtained 0.72 be in high category, because it has a mixing seagrass field.Keywords: community, composition, seagrass soliding. ABSTRAKPenelitian ini dilakukan di Perairan Kampung Ambong Kecamatan Likupang Timur Kabupaten Minahasa Utara.Tujuan dari penelitian ini mengetahui komposisi jenis lamun dan menganalisis kepadatan, indeks dominasi, indeks keanekaragaman, indeks kemerataan. Pengambilan data dilakukan dengan metode garis transek. Penempatan transek di bagi menjadi 3 garis transek yang di letakkan tegak lurus garis pantai dengan panjang masing-masing garis transek 95 meter. Sedangkan jarak antara transek 1 dengan transek yang lain (2 dan 3) masing-masing 100 m. Dari hasil penelitian komposisi jumlah spesies lamun (seagrass) adalah 10. Kesepuluh spesies yang teridentifikasi yaitu: Cymodocea rotundata, Syringodium isoetifolium, Halophila decipiens, Halodule pinifolia, Cymodocea serrulata, Enhalus acoroides, Halphila minor, Thalassia hempricii, Halodule uninervis, Halophila spinulosa.Kepadatan masing-masing spesies diperoleh menunjukkan nilai tertinggi yaitu Cymodocea rotundata 2608 individu/m2, Syringodium isoetifolium 816 individu/m2, Halophila decipiens 420 individu/m2, Halodule pinifolia 292 individu/m2, Cymodocea serrulata 268 individu/m2, Enhalus acoroides 260 individu/m2, Halophila minor 224 individu/m2, Thalassia hempricii 160individu/m2, Halodule uninervis 124individu/m2, Halophila spinulosa 20 individu/m2. Sedangkan indeks dominasi diperoleh 0.3 berada dalam kategori rendah, artinya tidak ada spesies yang mendominasi di perairan tersebut. Indeks keanekaragaman diperoleh 1.65 berada dalam kategori sedang. Hal ini menunjukkan bahwa komunitas spesies dalam kondisihampir merata, karena memiliki peluang yang sama. Indeks kemerataan diperoleh 0.72 berada dalam kategori tinggi, karena memiliki padang lamun campuran.Kata kunci : komunitas, komposisi, kepadatan lamun.

Fecal bacterial communities of wild-captured and stranded green turtles (Chelonia mydas) on the Great Barrier Reef.

Green turtles (Chelonia mydas) are endangered marine herbivores that break down food particles, primarily sea grasses, through microbial fermentation. However, the microbial community and its role in health and disease is still largely unexplored. In this study, we investigated and compared the fecal bacterial communities of eight wild-captured green turtles to four stranded turtles in the central Great Barrier Reef regions that include Bowen and Townsville. We used high-throughput sequencing analysis targeting the hypervariable V1-V3 regions of the bacterial 16S rRNA gene. At the phylum level, Firmicutes predominated among wild-captured green turtles, followed by Bacteroidetes and Proteobacteria. In contrast, Proteobacteria (Gammaproteobacteria) was the most significantly dominant phylum among all stranded turtles, followed by Bacteroidetes and Firmicutes. In addition, Fusobacteria was also significantly abundant in stranded turtles. No significant differences were found between the wild-captured turtles in Bowen and Townsville. At the family level, the core bacterial community consisted of 25 families that were identified in both the wild-captured and stranded green turtles, while two unique sets of 14 families each were only found in stranded or wild-captured turtles. The predominance of Bacteroides in all groups indicates the importance of these bacteria in turtle gut health. In terms of bacterial diversity and richness, wild-captured green turtles showed a higher bacterial diversity and richness compared with stranded turtles. The marked differences in the bacterial communities between wild-captured and stranded turtles suggest the possible dysbiosis in stranded turtles in addition to potential causal agents.

Biorock Electric Reefs Grow Back Severely Eroded Beaches in Months

Severely eroded beaches on low lying islands in Indonesia were grown back in a few months—believed to be a record—using an innovative method of shore protection, Biorock electric reef technology. Biorock shore protection reefs are growing limestone structures that get stronger with age and repair themselves, are cheaper than concrete or rock sea walls and breakwaters, and are much more effective at shore protection and beach growth. Biorock reefs are permeable, porous, growing, self-repairing structures of any size or shape, which dissipate wave energy by internal refraction, diffraction, and frictional dissipation. They do not cause reflection of waves like hard sea walls and breakwaters, which erodes the sand in front of, and then underneath, such structures, until they collapse. Biorock reefs stimulate settlement, growth, survival, and resistance to the environmental stress of all forms of marine life, restoring coral reefs, sea grasses, biological sand production, and fisheries habitat. Biorock reefs can grow back eroded beaches and islands faster than the rate of sea level rise, and are the most cost-effective method of shore protection and adaptation to global sea level rise for low lying islands and coasts.

Semi-isolated, flat-topped carbonate platform (Oligo-Miocene, Sardinia, Italy): Sedimentary architecture and processes

The Chattian-Aquitanian carbonate system of Isili sub-basin (SE Sardinia, Italy) were studied to better understand the hydrodynamic processes controlling the formation of landward-downlapping, rhodolith-rich, giant clinoforms.The studied flat-topped platform was attached to an island (semi-isolated) and migrated onshore (landward) over a shallow marine, protected embayment. The depositional profile is characterized by four, sea to land, zones: seaward slope, flat-topped platform (submerged flat), landward slope and mixed siliciclastic-carbonate embayment. In particular, these zones record different levels, from high to moderate, of hydrodynamic energy and persistency. The paleodepth of the studied succession, based on T/D test on Amphistegina specimens, red-algal genera and geometric reconstruction of the overall system, ranges from −10 to −30m for the platform up to around −40m for the landward slope base. Thus, the flat-topped platform was permanently submerged and an extensive carbonate (sea grass, algal and bryozoan-algal) factory along with oyster framestones developed. The widespread presence in the barren zones of rhodolith-to-shell rich small to very small compound dunes (high-energy zone) suggests that the flat-topped platform was periodically swept by unidirectional, landward-directed currents. These currents allow the formation of large-scale, rhodolith-rich clinobeds along the landward slope (washover fan-like system). The presence of rodolith pavements developed along the flat-topped platform at or slightly below the fairweather wave base suggests that clinobeds were formed in a nearshore, shallow subtidal setting. Finally, the shallow marine, protected embayment (moderate-energy zone) represents the widening distal reaches of the currents flowing or along the clinoforms or from the coast basinward (river floods and/or ebb tidal currents).Despite few tidal-related sedimentary structures such as bi-directional ripples and small compound dunes separated by finer-grained “drapes” or reactivation surfaces were observed, the prevailing processes acting over the platform are unidirectional, landward-directed currents possibly associated with longshore currents and/or wave actions. However, the resultant migration of the whole system onshore (landward) cannot be easily explained with storm or wind-related processes. Thus the studied flat-topped platform seems to be controlled by long term tidal regulation within a meso to macro tidal regime. In particular, such meso/macro tidal environments experience multiannual to multidecennial phases of stronger/weaker tidal range fluctuations resembling periods of relatively sea highs and lows with respect to the mean sea level (0m). All the (wind, storm, wave and tidal) currents sweeping the flat-topped platform were maxima during phases of strong tidal fluctuations generating erosion and sediment transportation over the flat and accumulation on the landward slope (clinobeds). Conversely, during phases of weaker tidal range fluctuations overall currents were minima, clinoforms did not develop and factories widespread re-colonized the submerged flat. Therefore, the studied platform developed in a current-dominated and tidal modulated setting.Finally, the studied carbonates of Sardinia suggest that the Sardinian seaway and the incipient Provençal basin during the Chattian-Aquitanian were, locally, capable to generate meso to macro tidal conditions.

Island populations have less genetic variation, but are more genetically isolated than mainland populations in anecosystem engineer, seagrass ( Zostera marina ) in South Korea: conservation implications for future management

Island populations have less genetic variation, but are more genetically isolated than mainland populations in anecosystem engineer, seagrass ( Zostera marina ) in South Korea: conservation implications for future management