Records of sea star (Echinodermata, Asteroidea) diversity in a disturbed tropical seagrass meadow

This study aims to record the sea star distribution in seagrass meadows within Sungai Pulai estuary (Johor, Malaysia) that is under pressure from coastal modification activities. The sampling sites were Merambong Shoal, Tanjung Adang Shoal, Tanjung Bin and Sungai Duku. From January 2016 to March 2018, we surveyed the areas to provide an inventory of sea star species sighted during the lowest tides. A total of seven species were observed, with Merambong Shoal having the highest number of species (seven species) while Sungai Duku and Tanjung Bin had the lowest (one species). We report the first sighting of Astropecten vappa in the area. Combined with past studies, there are now a total of eight sea star species in this area. As baseline records, our findings for the sea star community are applicable to the management of the seagrass habitat and help to create awareness of sea star diversity in the area. Data published in Mendeley (Doi:10.17632/dzjdnnbykv.1)Registros de diversidad de estrellas de mar (Echinodermata, Asteroidea) en un una pradera marina tropical alterada El objetivo de este estudio es registrar la distribución de estrellas de mar en las praderas marinas del estuario Sungai Pulai (Johor, Malasia), donde están sometidas a presión ambiental debido a la modificación de las actividades en la costa. Los puntos de muestreo fueron Merambong Shoal, Tanjung Adang Shoal, Tanjung Bin y Sungai Duku. Desde enero de 2016 hasta marzo de 2018 observamos las áreas de estudio para realizar un inventario de las especies de estrellas de mar presentes durante la marea baja. Observamos un total de siete especies, siendo Merambong Shoal el área con el mayor número de especies (siete especies), mientras que Sungai Duku y Tanjung Bin presentaron el número más bajo (una especie). Registramos la primera observación de Astropecten vappa en esta área, que sumada a los hallazgos de estudios anteriores supone un total de ocho especies. Nuestros hallazgos referentes a la comunidad estrellas de mar podrían ser aplicables como valores de referencia para la gestión de las praderas marinas como hábitat, así como para sensibilizar acerca de la diversidad de estrellas de mar en esta área. Datos publicados en Mendeley (Doi:10.17632/dzjdnnbykv.1)Registres de diversitat d’estrelles de mar (Echinodermata: Asteroidea) en un una praderia marina tropical alterada L’objectiu d’aquest estudi és registrar la distribució d’estrelles de mar a les praderies marines de l’estuari Sungai Pulai (Johor, Malàisia), on estan sotmeses a pressió ambiental a causa de la modificació de les activitats a la costa. Els punts de mostreig van ser Merambong Shoal, Tanjung Adang Shoal, Tanjung Bin i Sungai Duku. Des del gener de 2016 fins al març de 2018 vam observar les àrees d’estudi per fer un inventari de les espècies d’estrelles de mar presents durant la marea baixa. Hi vam observar un total de set espècies. L’àrea de Merambong Shoal és la que va presentar un nombre més gran d’espècies, set, mentre que Sungai Duku i Tanjung Bin van presentar el nombre més baix, una cadascun. Vam registrar la primera observació d’Astropecten vappa en aquesta àrea, que sumada a les troballes d’estudis anteriors suposa un total de vuit espècies. Les nostres troballes referents a la comunitat d’estrelles de mar podrien ser aplicables com a valors de referència per a la gestió de les praderies marines com a hàbitat i també per sensibilitzar sobre la diversitat d’estrelles de mar en aquesta àrea. Dades publicades a Mendeley (Doi:10.17632/dzjdnnbykv.1

Organic chemistry insights for the exceptional soil carbon storage of the seagrass Posidonia australis

The high organic carbon (OC) stores in seagrass meadows have led to their recognition as significant Blue Carbon sinks, though the diagenetic conditions that enable OC retention in seagrass soils remain poorly understood. In this study, seagrass soils were sampled from a Posidonia australis meadow in Oyster Harbour (Albany; south-western Australia) to investigate the preservation of sedimentary OC. We analysed soil characteristics (colour, grain size and redox potential), radiocarbon age, and characterised the soil organic matter (OM) using solid state CP/MAS 13C NMR spectroscopy to examine the preservation of OM down the soil profile. There was minimal change in organic composition over 1,700 years of accumulation, indicating long-term OM preservation. Primarily, this preservation appears to be driven by the recalcitrance of seagrass detritus buried in anoxic soils. The majority (70–83%) of total sedimentary OM comprised components directly attributable to seagrass origins (lignin, carbohydrate and black carbon-like matter), while the remainder consisted mostly of protein, some of which may have been present in seagrass biomass, along with likely contributions from algae and microbes. Although black carbon originates from organic matter combustion, here we provide evidence that the 13C NMR signal identified as black carbon-like matter in our soils is possibly associated with seagrass-derived organic matter consisting of degraded lignin products or other non-pyrogenic aromatics. The increase in the relative abundance of this black carbon-like matter with aging suggests its selective preservation. The relative abundances of carbohydrates significantly decreased with age down core (i.e. they appeared to be selectively decomposed), while lignin and protein did not show any quantitative changes in relative abundance (non-selective preservation). These findings demonstrate the exceptional preservation of P. australis derived OC, which contributes to our understanding of the higher OC storage capacity of Posidonia compared to other seagrass species.Oscar Serrano, Mohammad Rozaimi, Paul S. Lavery, Ronald J. Smerni

PHYSICAL IMPACT OF SEA LEVEL RISE TO THE COASTAL ZONE ALONG THE EAST COAST OF PENINSULAR MALAYSIA

Sea level rise around the world caused by global warming since decade and effects on coastal especially country below mean sea level and country island. The prediction of sea level rise by 2100 is over 3m. Sea level rise increases caused by melting ice and thermal expansion. The impact of sea level rise concentrated along the coastal area. This paper studied the impact of sea level rise to physical parameters along the East Coast of Peninsular Malaysia. Seven physical variables such as geomorphology, shoreline change rate, coastal slope, lithology, maximum wave height, mean tidal range and sea level change were chosen to find an physical vulnerability index. The index also was mapped using ArcGIS software to picture the vulnerability. The worst area for physical vulnerability index is along the Pahang coastline especially Kuantan district. The prevention and adaptation from government and nongovernment agencies should be taken to reduce the effects of sea level rise

Bioprospecting desert plant Bacillus endophytic strains for their potential to enhance plant stress tolerance

© 2019, The Author(s). Plant growth-promoting bacteria (PGPB) are known to increase plant tolerance to several abiotic stresses, specifically those from dry and salty environments. In this study, we examined the endophyte bacterial community of five plant species growing in the Thar desert of Pakistan. Among a total of 368 culturable isolates, 58 Bacillus strains were identified from which the 16 most divergent strains were characterized for salt and heat stress resilience as well as antimicrobial and plant growth-promoting (PGP) activities. When the 16 Bacillus strains were tested on the non-host plant Arabidopsis thaliana, B. cereus PK6-15, B. subtilis PK5-26 and B. circulans PK3-109 significantly enhanced plant growth under salt stress conditions, doubling fresh weight levels when compared to uninoculated plants. B. circulans PK3-15 and PK3-109 did not promote plant growth under normal conditions, but increased plant fresh weight by more than 50% when compared to uninoculated plants under salt stress conditions, suggesting that these salt tolerant Bacillus strains exhibit PGP traits only in the presence of salt. Our data indicate that the collection of 58 plant endophytic Bacillus strains represents an important genomic resource to decipher plant growth promotion at the molecular level

Key biogeochemical factors affecting soil carbon storage in Posidonia meadows

Unidad de excelencia María de Maeztu MdM-2015-0552Biotic and abiotic factors influence the accumulation of organic carbon (Corg) in seagrass ecosystems. We surveyed Posidonia sinuosa meadows growing in different water depths to assess the variability in the sources, stocks and accumulation rates of Corg. We show that over the last 500 years, P. sinuosa meadows closer to the upper limit of distribution (at 2-4m depth) accumulated 3- to 4-fold higher Corg stocks (averaging 6.3 kg Corg m¯²/ at 3- to 4-fold higher rates (12.8 gCorg m¯² yr¯¹/ compared to meadows closer to the deep limits of distribution (at 6-8m depth; 1.8 kg Corg m¯² and 3.6 g Corg m¯² yr¯¹/. In shallower meadows, Corg stocks were mostly derived from seagrass detritus (88% in average) compared to meadows closer to the deep limit of distribution (45% on average). In addition, soil accumulation rates and fine-grained sediment content (< 0.125 mm) in shallower meadows (2.0mm yr¯¹ and 9 %, respectively) were approximately 2-fold higher than in deeper meadows (1.2mm yr¯¹ and 5 %, respectively). The Corg stocks and accumulation rates accumulated over the last 500 years in bare sediments (0.6 kg Corg m¯² and 1.2 g Corg m¯² yr¯¹/ were 3- to 11-fold lower than in P. sinuosa meadows, while fine-grained sediment content (1 %) and seagrass detritus contribution to the Corg pool (20 %) were 8- and 3-fold lower than in Posidonia meadows, respectively. The patterns found support the hypothesis that Corg storage in seagrass soils is influenced by interactions of biological (e.g., meadow productivity, cover and density), chemical (e.g., recalcitrance of Corg stocks) and physical (e.g., hydrodynamic energy and soil accumulation rates) factors within the meadow. We conclude that there is a need to improve global estimates of seagrass carbon storage accounting for biogeochemical factors driving variability within habitats

Australian vegetated coastal ecosystems as global hotspots for climate change mitigation

Policies aiming to preserve vegetated coastal ecosystems (VCE; tidal marshes, mangroves and seagrasses) to mitigate greenhouse gas emissions require national assessments of blue carbon resources. Here, we present organic carbon (C) storage in VCE across Australian climate regions and estimate potential annual CO2 emission benefits of VCE conservation and restoration. Australia contributes 5–11% of the C stored in VCE globally (70–185 Tg C in aboveground biomass, and 1,055–1,540 Tg C in the upper 1 m of soils). Potential CO2 emissions from current VCE losses are estimated at 2.1–3.1 Tg CO2-e yr-1, increasing annual CO2 emissions from land use change in Australia by 12–21%. This assessment, the most comprehensive for any nation to-date, demonstrates the potential of conservation and restoration of VCE to underpin national policy development for reducing greenhouse gas emissions

Australian vegetated coastal ecosystems as global hotspots for climate change mitigation

© 2019, The Author(s). Policies aiming to preserve vegetated coastal ecosystems (VCE; tidal marshes, mangroves and seagrasses) to mitigate greenhouse gas emissions require national assessments of blue carbon resources. Here, we present organic carbon (C) storage in VCE across Australian climate regions and estimate potential annual CO2 emission benefits of VCE conservation and restoration. Australia contributes 5–11% of the C stored in VCE globally (70–185 Tg C in aboveground biomass, and 1,055–1,540 Tg C in the upper 1 m of soils). Potential CO2 emissions from current VCE losses are estimated at 2.1–3.1 Tg CO2-e yr-1, increasing annual CO2 emissions from land use change in Australia by 12–21%. This assessment, the most comprehensive for any nation to-date, demonstrates the potential of conservation and restoration of VCE to underpin national policy development for reducing greenhouse gas emissions

Australian vegetated coastal ecosystems as global hotspots for climate change mitigation

Unidad de excelencia María de Maeztu MdM-2015-0552Policies aiming to preserve vegetated coastal ecosystems (VCE; tidal marshes, mangroves and seagrasses) to mitigate greenhouse gas emissions require national assessments of blue carbon resources. Here, we present organic carbon (C) storage in VCE across Australian climate regions and estimate potential annual CO emission benefits of VCE conservation and restoration. Australia contributes 5-11% of the C stored in VCE globally (70-185 Tg C in aboveground biomass, and 1,055-1,540 Tg C in the upper 1 m of soils). Potential CO emissions from current VCE losses are estimated at 2.1-3.1 Tg CO-e yr, increasing annual CO emissions from land use change in Australia by 12-21%. This assessment, the most comprehensive for any nation to-date, demonstrates the potential of conservation and restoration of VCE to underpin national policy development for reducing greenhouse gas emissions

Sediment properties as important predictors of carbon storage in zostera marina meadows: a comparison of four European areas

Seagrass ecosystems are important natural carbon sinks but their efficiency varies greatly depending on species composition and environmental conditions. What causes this variation is not fully known and could have important implications for management and protection of the seagrass habitat to continue to act as a natural carbon sink. Here, we assessed sedimentary organic carbon in Zostera marina meadows (and adjacent unvegetated sediment) in four distinct areas of Europe (Gullmar Fjord on the Swedish Skagerrak coast, Asko in the Baltic Sea, Sozopol in the Black Sea and Ria Formosa in southern Portugal) down to similar to 35 cm depth. We also tested how sedimentary organic carbon in Z. marina meadows relates to different sediment characteristics, a range of seagrass-associated variables and water depth. The seagrass carbon storage varied greatly among areas, with an average organic carbon content ranging from 2.79 +/- 0.50% in the Gullmar Fjord to 0.17 +/- 0.02% in the area of Sozopol. We found that a high proportion of fine grain size, high porosity and low density of the sediment is strongly related to high carbon content in Z. marina sediment. We suggest that sediment properties should be included as an important factor when evaluating high priority areas in management of Z. marina generated carbon sinks

In silico exploration of Red Sea Bacillus genomes for natural product biosynthetic gene clusters

Background: The increasing spectrum of multidrug-resistant bacteria is a major global public health concern, necessitating discovery of novel antimicrobial agents. Here, members of the genus Bacillus are investigated as a potentially attractive source of novel antibiotics due to their broad spectrum of antimicrobial activities. We specifically focus on a computational analysis of the distinctive biosynthetic potential of Bacillus paralicheniformis strains isolated from the Red Sea, an ecosystem exposed to adverse, highly saline and hot conditions. Results: We report the complete circular and annotated genomes of two Red Sea strains, B. paralicheniformis Bac48 isolated from mangrove mud and B. paralicheniformis Bac84 isolated from microbial mat collected from Rabigh Harbor Lagoon in Saudi Arabia. Comparing the genomes of B. paralicheniformis Bac48 and B. paralicheniformis Bac84 with nine publicly available complete genomes of B. licheniformis and three genomes of B. paralicheniformis, revealed that all of the B. paralicheniformis strains in this study are more enriched in nonribosomal peptides (NRPs). We further report the first computationally identified trans-acyltransferase (trans-AT) nonribosomal peptide synthetase/polyketide synthase (PKS/ NRPS) cluster in strains of this species. Conclusions:B. paralicheniformis species have more genes associated with biosynthesis of antimicrobial bioactive compounds than other previously characterized species of B. licheniformis, which suggests that these species are better potential sources for novel antibiotics. Moreover, the genome of the Red Sea strain B. paralicheniformis Bac48 is more enriched in modular PKS genes compared to B. licheniformis strains and other B. paralicheniformis strains. This may be linked to adaptations that strains surviving in the Red Sea underwent to survive in the relatively hot and saline ecosystems