Search results for "Seagra"
showing 10 items of 101 documents
Antioxidant Bioactivity of Extracts from Beach Cast Leaves of Posidonia oceanica (L.) Delile
2021
The marine environment is a generous source of biologically active compounds useful for human health. In 50 years, about 25,000 bioactive marine compounds have been identified, with an increase of 5% per year. Peculiar feature of algae and plants is the production of secondary metabolites, such as polyphenols, synthesized as a form of adaptation to environmental stress. Posidonia oceanica is a Mediterranean endemic and dominant seagrass and represents a biologically, ecologically and geologically important marine ecosystem. Within this study, methanolic and ethanolic extracts were generated from fresh and dried Posidonia 
The sanitation service of seagrasses – Dependencies and implications for the estimation of avoided costs
2022
Seagrasses are capable of sanitizing coastal seawaters polluted by fecal bacteria. In this work, the reduction of Enterococci concentration in the presence of a seagrasses’ assemblage (Pacific Ocean) was related to the decrease in the probability of gastroenteritis. A linear model fitted to data extracted from the literature showed a 20% reduction of this probability in the presence of these plants. Seagrass sanitation effect was estimated to allow avoiding ca. 24 million gastroenteritis cases/year, globally. Considering a global cost of gastroenteritis of ca. US$ 372 million/year, the global avoided cost, assuming that the sanitation service was always effective, was estimated to be ca. US…
Detection and mapping of "blue carbon" reservoir storage in Posidonia oceanica dead matte in front of an extensive industrial area
2015
The endemic Mediterranean seagrass Posidonia oceanica is the only marine phanerogam able to form matte, a biogenic structure representing important long-term “blue carbon” reservoir. Natural and/or anthropogenic factors can lead to the formation of a regressive structure, called “dead matte”, resulting from the disappearance of living shoots in the upper part of the matte. In the framework of TETIDE project (PON01_03112, www.progettotetide.it) a multiple sensors acoustic survey -multibeam sonar (MBS), side scan sonar (SSS), sub-bottom profiler (SBP) -was carried out in a portion of the Gulf of Augusta (Sicily, Southern Ionian Sea). The aim of investigation was to estimate the extent of dead…
Stakeholders’ Attitudes about the Transplantations of the Mediterranean Seagrass Posidonia oceanica as a Habitat Restoration Measure after Anthropoge…
2021
Anthropogenic impacts on Posidonia oceanica meadows have led to a decline of this ecosystem throughout the Mediterranean. Transplantations have often been prescribed as a compensation measure to mitigate the impacts caused by coastal maritime works. Here a Q methodology approach was used to investigate the stakeholders’ attitudes in four case studies of P. oceanica transplants realized in Italian waters. Twenty-two respondents were asked to score 37 statements, and the resultant Q-sorting was analyzed via an inverse PCA using the KADE software. Four discourses, corresponding to the significant axes in the factorial analysis were identified: science and conservation (F1), oriented at a rigor…
Colonisation process of vegetative fragments of Posidonia oceanica (L.) Delile on rubble mounds
2005
Seagrass colonise new areas via the dispersion of seeds or vegetative fragments. Independent of the manner of colonization, habitat requirements need to be met for the successful establishment of seagrasses. Here we report on the colonization process of Posidonia oceanica in a highly disturbed area: a gas pipeline trench at Capo Feto (SW Sicily, Italy). A trench dredged through a P. oceanica bed was back-filled with rubble added from dump barges leading to the formation of a series of rubble mounds on the seabed. Over time, these mounds became colonised with P. oceanica. In order to understand the pattern of P. oceanica colonization, shoot density was quantified over 3 years (2001-2003) on …
Community Structure of Gastropods in Seagrass Meadows at Coastal Area of Nusi and Gersen, Nabire Regency
2020
Gastropods plays an important role in the food chain on seagrass ecosystem and its existence are depend on the physical-chemical factors in the seagrass ecosystem. This study aims to determine the density and diversity of gastropods associated in seagrass habitat in Nusi and Gersen coastal waters. The measurement results of some physical-chemical waters variables, are still quite good for the life of gastropods. Species composition of gastropod in Nusi at higher than at the Gersen, but instead of individual density in Gersen more higher than Nusi. Diversity index of gastropods at Nusi station is higher (3,757) than Gersen (3.053), on the contrary the eveness and dominance index are higher a…
Heavy Metal Contents in Soft-Bottom Marine Macrophytes and Sediments Along the Mediterranean Coast of Spain
2000
. Hg, Cd, Pb and Zn concentrations were determined in sediment and in tissues of five species of soft-bottom marine macrophytes (Posidonia oceanica, Cymodocea nodosa, Zostera noltii, Ruppia cirrhosa and Caulerpa prolifera) along the Spanish Mediterranean coast. Levels of metals were low in most of the sampling stations and similar to those found by other authors in uncontaminated zones. Certain locations, however, showed some degree of contamination (Cambrils, Almassora, Alacant, Mar Menor and El Portus). In Santa Pola we found high contents of metals in one sample of sediment due to the high proportion of the fine fraction (particules < 63µm) and organic matter, but not in the seagrass spe…
Effect of explosive shallow hydrothermal vents on δ13C and growth performance in the seagrass Posidonia oceanica
2010
Summary 1. Explosive volcanic submarine activity is expected to affect seagrass communities due to sudden and dramatic changes in the physical and chemical features of sea water and sediments, with possibly large ecosystem effects. However, seagrass response to the harsh environmental conditions that arise due to explosive volcanism is as yet unexplored as it is not easy to predict when and where an eruption will occur. Here, we investigate the uptake of hydrothermal carbon within the seagrass Posidonia oceanica by the analysis of δ13C and growth rates in tissue laid down before and after an exceptional and massive hydrothermal gas release in the Aeolian Islands (Italy, Mediterranean Sea). …
BIOMASSA AND ACCUMULATION CARBON ON SEAGRASS Enhalus acroides IN GUNUNG BOTAK BAY COASTAL, WEST PAPUA
2018
Seagrass is a high level and a flowering plant that is fully adapted to life in the coastal and has ability to store carbon by 10% of the carbon content in the oceans. The research doing at Gunung Botak Bay Coastal South Manokwari Regency with objective of research to estimate seagrass density and to estimate rate accumulation of carbon from Enhalus acroides. Some the stages of the research done is density sample as long to period 2015 (April and Mei) into (September and Ocktober). Other sampling to collecting seagrass to estimate carbon storage in part like daun, rhizome root and substrat. Result to showing average carbon accumulation of seagrass in above below ground is rhizome part and h…
Slight differences in community structure and biodiversity of fish associated to a Cymodocea nodosa meadow in a shallow CO2 vent
2018
Naturally acidified environments are used to test ecological hypotheses about the effects of ocean acidification on complex communities. Here, we used a shallow Mediterranean CO2 vent to study the coastal fish assemblages associated to Cymodocea nodosa seagrass meadows, long-term exposed to high pCO2 / low pH conditions. In particular, by using underwater visual census method, we assessed the structure and the biodiversity of fish assemblages living in a low pH site and in two control sites, in two periods of the year featured by dissimilar seagrass structure. The aim of this study was to test the effect of different pH on fish assemblages mediated by the habitat-forming structural species …