Search results for "brackish"
showing 10 items of 55 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…
The genus Ruppia L. (Ruppiaceae) in the Mediterranean region: An overview
2015
Abstract This paper reviews the current knowledge on the diversity, distribution and ecology of the genus Ruppia L. in the Mediterranean region. The genus Ruppia, a cosmopolitan aquatic plant complex, is generally restricted to shallow waters such as coastal lagoons and brackish habitats characterized by fine sediments and high salinity fluctuations. In these habitats Ruppia meadows play an important structural and functional role. Molecular analyses revealed the presence of 16 haplotypes in the Mediterranean region, one corresponding to Ruppia maritima L., and the others to various morphological forms of Ruppia cirrhosa (Petagna) Grande, all together referred to as the “R. cirrhosa s.l. co…
Reverse electrodialysis with saline waters and concentrated brines: A laboratory investigation towards technology scale-up
2015
Abstract The use of concentrated brines and brackish water as feed solutions in reverse electrodialysis represents a valuable alternative to the use of river/sea water, allowing the enhancement of power output through the increase of driving force and reduction of internal stack resistance. Apart from a number of theoretical works, very few experimental investigations have been performed so far to explore this possibility. In the present work, two RED units of different size were tested using artificial saline solutions. The effects of feed concentration, temperature and flowrate on process performance parameters were analysed, adopting two different sets of membranes. These experiments all…
Performance of the first reverse electrodialysis pilot plant for power production from saline waters and concentrated brines
2016
Abstract This work reports experimental data collected for the first time on a full-scale RED pilot plant operated with natural streams in a real environment. The plant – located in the South of Italy – represents the final accomplishment of the REAPower project ( www.reapower.eu ). A RED unit equipped with almost 50 m2 of IEMs (125 cell pairs, 44x44 cm2) was tested, using both artificial and natural feed solutions, these latter corresponding to brackish water (≈0.03 M NaClequivalent) and saturated brine (4–5 M NaClequivalent). A power output up to around 40 W (i.e. 1.6 W/m2 of cell pair) was reached using natural solutions, while an increase of 60% was observed when testing the system with…
Towards 1 kW power production in a reverse electrodialysis pilot plant with saline waters and concentrated brines
2017
Abstract Reverse electrodialysis (RED) is a promising technology to extract energy from salinity gradients, especially in the areas where concentrated brine and saline waters are available as feed streams. A first pilot-scale plant was recently built in Trapani (Italy), and tested with real brackish water and brine from saltworks. The present work focuses on the scale-up of the pilot plant, reaching more than 400 m 2 of total membrane area installed and representing the largest operating RED plant so far reported in the literature. With a nominal power capacity of 1 kW, the pilot plant reached almost 700 W of power capacity using artificial brine and brackish water, while a 50% decrease in …
Current distribution along electrodialysis stacks and its influence on the current-voltage curve: behaviour from near-zero current to limiting plateau
2023
The current maldistribution along the flow path of electrodialysis (ED) units is a well-known phenomenon. However, it has been poorly quantified via experimental tests so far. This work aimed at measuring the current distribution in an ED stack with 40 cm path length, provided with four-segment electrodes. The current-voltage curve (CVC) of each segment was recorded under several operating conditions of inlet concentrations and feed velocity. In the CVC of the first segment, the current increased approaching a saturation, while in that of the remaining segments it passed through a maximum and then settled at near-zero values when high voltage values were applied. The current fraction on the…
REAPOWER – USE OF DESALINATION BRINE FOR POWER PRODUCTION THROUGH REVERSE ELECTRODIALYSIS
2015
Salinity gradient power (SGP) represents a viable renewable energy source associated with the mixing of two solutions of different salinities. Reverse electrodialysis (SGP-RE or RED) is a promising technology to exploit this energy source and directly generate electricity. However, although the principle of this technology is well known since several years, further R&D efforts are still necessary in order to explore the real potential of the SGP-RE process. With this regard, the aim of the REAPower project ( [GRAPHICS] ) is the development of an innovative system for power production by SGP-RE process, using sea (or brackish) water as a diluted solution and brine as a concentrate. The use o…
Body size variability across habitats in the Brachionus plicatilis cryptic species complex
2020
AbstractThe body size response to temperature is one of the most recognizable but still poorly understood ecological phenomena. Other covarying environmental factors are frequently invoked as either affecting the strength of that response or even driving this pattern. We tested the body size response in five species representing the Brachionus plicatilis cryptic species complex, inhabiting 10 brackish ponds with different environmental characteristics. Principal Component Analysis selected salinity and oxygen concentration as the most important factors, while temperature and pH were less influential in explaining variation of limnological parameters. Path analysis showed a positive interclo…
Microbiome of the Black Sea Water Column Analyzed by Genome Centric Metagenomics  
2020
Abstract Background: The Black Sea is the largest brackish water body in the world, although it is connected to the Mediterranean Sea and presents an upper water layer similar to some regions of the former albeit with lower salinity and (mostly) temperature. In spite of its well-known hydrology and physico chemistry, this enormous water mass remains poorly studied at the microbial genomics level. Results: We have sampled its different water masses and analyzed the microbiome by classic and genome-resolved metagenomics generating a large number of metagenome-assembled genomes (MAGs) from them. The oxic zone presents many similarities to the global ocean while the euxinic water mass has simil…
Phytoplankton Fluctuations during an Annual Cycle in the Coastal Lagoon of Cullera (Spain)
1989
The seasonal variation and the vertical distribution of the phytoplanktonic population of the lagoon of Cullera, an elongated coastal lagoon with estuarine circulation of water, has been studied in three sampling stations: mouth, centre and source. Seasonal variation is determined by a marine-freshwater interaction. In winter, the sea influence is important, a marine water wedge of anoxic water arrives at the sampling station located at the source and marine and brackish water species dominate the phytoplankton. Also marine species of zooplankton and fish enter the system, which may then be considered as exploited by the sea. In spring the marine wedge retreats from the source but remains i…