Search results for "Brackish water"

Mid-Holocene tectonic geomorphology of northern Crete deduced from a coastal sedimentary archive near Rethymnon and a Late Bronze Age Santorini tsuna…

2019

Abstract The Late Bronze Age (LBA) tsunami and the A.D. 365 tsunami are supposed to have affected the northern coasts of Crete. However, near-coast sedimentary archives have been rarely investigated in this area, and sedimentary archives including palaeotsunami fingerprints are still unknown. The main objective of our research was to search for appropriate tsunami sediment traps in order to gain detailed insights into the Holocene palaeotsunami history of northern Crete. We found an excellent fine sediment archive near Pirgos, located to the west of Rethymnon. Based on a multi-electrode geoelectrical survey and an 11-m-deep sediment core, we analysed the event-geochronostratigraphical recor…

Comparison of Diatoms and Dinoflagellates from Different Habitats as Sources of PUFAs

2019

Recent studies have clearly shown the importance of omega-3 (&omega

Persistence of submerged macrophytes in a drying world: Unravelling the timing and the environmental drivers to produce drought-resistant propagules

2018

Morphological variations of crossed-lamellar ultrastructures of Glycymeris bimaculata (Bivalvia) serve as a marine temperature proxy

2020

Abstract Bivalve shells are among the most promising archives for high-resolution seawater temperature reconstructions. However, despite major research advances in bivalve sclerochronology over the past decades, estimating water temperature from shells remains a challenging task. This is largely because the most frequently used and widely accepted temperature proxy in bivalves, i.e., the shell oxygen isotope (δ18Oshell) value, also requires knowledge of changes in δ18O of the water (δ18Owater) in which the bivalve lived, which is rarely available for ancient environments. According to a few recent studies, the size and shape of individual biomineral units (BMUs) of the shell ultrastructure …

Use of microbial biostimulants to increase the salinity tolerance of vegetable transplants

2021

Vegetable plants are more sensitive to salt stress during the early growth stages

Mixotrophic phytoplankton dynamics in a shallow Mediterranean water body: how to make a virtue out of necessity

2018

Mixotrophy is a combination of photosynthesis and direct access to organic carbon sources, mainly through osmotrophy or phagotrophy. This strategy is adopted by several, phylogenetically distinct, phytoplankton groups and is commonly occurring in marine, brackish and freshwater ecosystems. Traditionally, it has been put in relation to both scarcity of inorganic nutrients and poor light conditions. However, we observed blooms of the mixotrophic, toxic haptophyte Prymnesium parvum in different periods of the year and under variable resources availability. The analysis of a 6.5-year data set of phytoplankton weekly records from a Sicilian shallow lake (Biviere di Gela, south-eastern Sicily) al…

Carbon metabolic rates and GHG emissions in different wetland types of the Ebro Delta

2020

Deltaic wetlands are highly productive ecosystems, which characteristically can act as C-sinks. However, they are among the most threatened ecosystems, being very vulnerable to global change, and require special attention towards its conservation. Knowing their climate change mitigating potential, conservation measures should also be oriented with a climatic approach, to strengthen their regulatory services. In this work we studied the carbon biogeochemistry and the specific relevance of certain microbial guilds on carbon metabolisms of the three main types of deltaic wetlands located in the Ebro Delta, north-eastern Spain, as well as how they deal with human pressures and climate change ef…

Changes in crustacean mesozooplankton and some environmental parameters in the Archipelago Sea (Northern Baltic) in 1976-1984

1990

Abstract The abundance of crustacean mesozooplankton was monitored by monthly sampling in the Archipelago Sea (Northern Baltic) during the years 1976-1984. Changes in the abundance of crustacean mesozooplankton species are compared with changes in water temperature, nutrient levels, chlorophyll-a, salinity and population densities of the Baltic herring (Clupea harengus membras L.). There was a rise of water temperature during the study period (about laC on average). The chlorophyll values were increasing, as were the nutrient levels in winter. Salinity was decreasing (on average 0.5‰ S). The biomass and abundance ofplanktivorous Baltic herring were increasing by about 30 and 50 per cent, re…

Acute and chronic response to a change in salinity of the euryhaline polychaete Pygospio elegans (Claparède)

2019

Abstract Estuaries are thought to be very harsh environments because their physico-chemical parameters, such as salinity, temperature and oxygen, can fluctuate substantially. The distribution of species living in an estuary is largely determined by how well they can cope with such fluctuations. The spionid polychaete Pygospio elegans is common in boreal estuarine habitats that show strong salinity fluctuations, living in habitats ranging from fully marine salinities to brackish environments with salinities as low as 5. In this study we investigated the abilities of P. elegans to cope with an acute as well as a long-term change in salinity. Specimens originating from a salinity of about 15 w…

Alleviation of Salt Stress by Plant Growth-Promoting Bacteria in Hydroponic Leaf Lettuce

2020

Mediterranean areas with intensive agriculture are characterized by high salinity of groundwater. The use of this water in hydroponic cultivations can lead to nutrient solutions with an electrical conductivity that overcomes the tolerance threshold of many vegetable species. Plant growth-promoting rhizobacteria (PGPR) were shown to minimize salt stress on several vegetable crops but the studies on the application of PGPR on leafy vegetables grown in hydroponics are rather limited and have not been used under salt stress conditions. This study aimed to evaluate the use of plant growth-promoting bacteria to increase the salt tolerance of leaf lettuce grown in autumn and spring in a floating s…