The dynamics of the nitrogen intermediates N2O and NO2 in estuarine sediments were studied along a salinity gradient in the eutrophied Weser Estuary (Germany) using microsensors for N2O, NO2, NOx, and O2. During dark incubations in the laboratory of sediment samples from a freshwater site, a brackish water site with fluctuating salinity, and a marine site, the effects of environmental changes i...

Coralline red algae are significant components of sea bottom and up to now considered as exclusively marine species. Here we present the first coralline alga from a freshwater environment, found in the Cetina River (Adriatic Sea watershed). The alga is fully adapted to freshwater, as attested by reproductive structures, sporelings, and an inability to survive brackish conditions. Morphological ...

Recent investigations of water balance in sea snakes demonstrated that amphibious sea kraits (Laticauda spp.) dehydrate in seawater and require fresh water to restore deficits in body water. Here, we report similar findings for Pelamis platurus, a viviparous, pelagic, entirely marine species of hydrophiine ("true") sea snake. We sampled snakes at Golfo de Papagayo, Guanacaste, Costa Rica and de...

Historical descriptions of the Clipperton lagoon appear to converge on the fact that it became isolated from the surrounding ocean around 1858. Since then, because of the high precipitation rate which largely exceeds evaporation in this region of the eastern tropical Pacific, a brackish lens has formed on top of the saline oceanic waters. In 1980, literature data show that the thickness of this...

The survival of 'atypical', cytochrome oxidase-negative Aeromonas salmonicida in microcosms containing sterilized water and sediment was assessed using the plate count method. The effect of sal~nity, temperature and presence of sediment was investigated on the survival of 2 strains isolated from ulcerated flounder Platjcl~thys flesus from the northern Baltic Sea. The strains survived for only a...

Capacitive Deionization [2] (CDI [3]) is a water [4] purification process that offers promise in the deionization of salt and brackish water [4]. The process can create potable water [4] out of salt laden water [4] by using electric currents to separate the ions in the solution and attract them to cathode and anode plates. These plates act as filters, drawing salt and other ionized metals out o...

Amoeboid protists that harbor bacterial pathogens are of significant interest as potential reservoirs of disease-causing organisms in the environment, but little is known about them in marine and other saline environments. We enriched amoeba cultures from sediments from four sites in the New England estuarine system of Mt. Hope Bay, Massachusetts and from sediments from six sites in the Great S...

Transitions from marine to freshwater habitats constitute dramatic shifts between 'adaptive zones' that have initiated the radiation and speciation of many taxa. As recently as 10?000 years ago, deglaciation resulted in marine fauna being trapped in freshwater lakes. In modern times, human activity has caused the acceleration of freshwater invasions from marine or brackish habitats, leading to ...

Divergent selection pressures induced by different environmental conditions typically lead to variation in life history, behavior, and morphology. When populations are locally adapted to their current environment, selection may limit movement into novel sites, leading to neutral and adaptive genetic divergence in allopatric populations. Subsequently, divergence can be reinforced by development ...