Search results for "Salinity"
showing 10 items of 374 documents
Heart beat rate adaptations to varying salinity of two intertidal Mediterranean bivalves: The invasiveBrachidontes pharaonisand the nativeMytilaster …
2011
Abstract Changes in heart beat rates (HBR) of Brachidontes pharaonis (an invasive Lessepsian species) and Mytilaster minimus (a native Mediterranean species) in response to changes in salinity values from brackish (20) to extreme hyper-saline (75) were investigated both in situ and in the laboratory. The two species displayed different responses to varying salinity, with clear differences in HBR observed between groups investigated at different salinities and between groups originating from different environments. The native species, adapted to narrow salinity changes as those observed in the superficial waters of the Mediterranean Sea, showed signs of stress at salinities slightly above 37…
Evidence of the Zanclean megaflood in the eastern Mediterranean Basin
2018
A. Micallef et. al.
Using LEACHM model for evaluation and optimization of the use low quality water in citrus
2018
Para evaluar el riesgo de salinizacion en suelos con cultivo de cítricos se utilizó el modelo LEACHM que fue calibrado y validado en 7 perfiles de la cuenca sedimentaria de Torreblanca (Castellón, España). Se aplicó un análisis de escenarios mediante la combinación de: cultivos, clima, suelos, tipo de riego y calidad de las aguas y se analizaron estrategias alternativas mediante la utilización de mezclas de aguas. Los índices estadísticos mostraron un buen ajuste del modelo en la zona radicular entre 200-600 mm y una sobreestimación de la humedad en los horizontes inferiores. En cuanto al riesgo de salinización los resultados confirmaron el uso inapropiado de las aguas con CE>3 dS/m. Se …
Danau Laut Balbullol di Misool Raja Ampat
2018
Danau laut adalah ekosistem unik yang ditemukan terfokus di empat lokasi saja di dunia. Salah satunya di Raja Ampat. Danau-danau tersebut memiliki karakter yang unik sesuai tingkat koneksinya dengan laut. Danau Balbullol adalah danau yang paling dalam diantara danau laut di Misool, terasing, dan belum pernah dikaji. Melalui studi ini ingin mengetahui karakter dari Danau Balbullol. Deskripsi danau dilakukan dengan serangkaian survei lapangan dan perekaman logger untuk mengetahui karakter fisik, kualitas air, dan kehadiran biota. Hasilnya diketahui luas danau adalah 1,94 ha dengan kedalaman maksimum 38 m. Suhu dan salinitas memperlihatkan profil vertikal yang homogen, sehingga membentuk tipe …
Habitat degradation correlates with tolerance to climate-change related stressors in the green mussel Perna viridis from West Java, Indonesia
2013
It is unclear whether habitat degradation correlates with tolerance of marine invertebrates to abiotic stress. We therefore tested whether resistance to climate change-related stressors differs between populations of the green mussel Perna viridis from a heavily impacted and a mostly pristine site in West Java, Indonesia. In laboratory experiments, we compared their oxygen consumption and mortality under lowered salinity (-13 and -18 units, both responses), hypoxia (0.5 mg/l, mortality only) and thermal stress (+7 degrees C, mortality only). Mussels from the eutrophied and polluted Jakarta Bay showed a significantly smaller deviation from their normal oxygen consumption and higher survival …
Elucidating the picocyanobacteria salinity divide through ecogenomics of new freshwater isolates
2022
Abstract Background Cyanobacteria are the major prokaryotic primary producers occupying a range of aquatic habitats worldwide that differ in levels of salinity, making them a group of interest to study one of the major unresolved conundrums in aquatic microbiology which is what distinguishes a marine microbe from a freshwater one? We address this question using ecogenomics of a group of picocyanobacteria (cluster 5) that have recently evolved to inhabit geographically disparate salinity niches. Our analysis is made possible by the sequencing of 58 new genomes from freshwater representatives of this group that are presented here, representing a 6-fold increase in the available genomic data. …
Acid trehalase is involved in intracellular trehalose mobilization during postdiauxic growth and severe saline stress in Saccharomyces cerevisiae.
2008
The role of the acid trehalase encoded by the ATH1 gene in the yeast Saccharomyces cerevisiae is still unclear. In this work, we investigated the regulation of ATH1 transcription and found a clear involvement of the protein kinase Hog1p in the induction of this gene under severe stress conditions, such as high salt. We also detected changes in the acid trehalase activity and trehalose levels, indicating a role of the acid trehalase in intracellular trehalose mobilization. Finally, the growth analysis for different mutants in neutral and acid trehalases after high salt stress implicates acid trehalase activity in saline stress resistance.
Fungal Assemblages Associated with Roots of Halophytic and Non-halophytic Plant Species Vary Differentially Along a Salinity Gradient
2012
Structure of fungal communities is known to be influenced by host plants and environmental conditions. However, in most cases, the dynamics of these variation patterns are poorly understood. In this work, we compared richness, diversity, and composition between assemblages of endophytic and rhizospheric fungi associated to roots of two plants with different lifestyles: the halophyte Inula crithmoides and the non-halophyte I. viscosa (syn. Dittrichia viscosa L.), along a spatially short salinity gradient. Roots and rhizospheric soil from these plants were collected at three points between a salt marsh and a sand dune, and fungi were isolated and characterized by ITS rDNA sequencing. Isolates…
Salinity and Bacterial Diversity: To What Extent Does the Concentration of Salt Affect the Bacterial Community in a Saline Soil?
2014
In this study, the evaluation of soil characteristics was coupled with a pyrosequencing analysis of the V2-V3 16S rRNA gene region in order to investigate the bacterial community structure and diversity in the A horizon of a natural saline soil located in Sicily (Italy). The main aim of the research was to assess the organisation and diversity of microbial taxa using a spatial scale that revealed physical and chemical heterogeneity of the habitat under investigation. The results provided information on the type of distribution of different bacterial groups as a function of spatial gradients of soil salinity and pH. The analysis of bacterial 16S rRNA showed differences in bacterial compositi…
New insights into the role of spermine in Arabidopsis thaliana under long-term salt stress
2010
Polyamines (putrescine, spermidine and spermine) are traditionally implicated in the response of plants to environmental cues. Free spermine accumulation has been suggested as a particular feature of long-term salt stress, and in the model plant Arabidopsis thaliana the spermine synthase gene (AtSPMS) has been reported as inducible by abscisic acid (ABA) and acute salt stress treatments. With the aim to unravel the physiological role of free spermine during salinity, we analyzed polyamine metabolism in A. thaliana salt-hypersensitive sos mutants (salt overlay sensitive; sos1-1, sos2-1 and sos3-1), and studied the salt stress tolerance of the mutants in spermine and thermospermine synthesis …