Search results for "MARINE"

Anaerobic oxidation of methane in sediments of a nitrate-rich, oligo-mesotrophic boreal lake

2021

AbstractThe identity of electron acceptors in promoting anaerobic oxidation of methane (AOM) in the sediments of boreal lakes is currently unknown. Here, we studied the AOM rate of sediment slurries collected from three profundal stations of a nitrate-rich, oligo-mesotrophic, boreal lake (Lake Pääjärvi, Finland), under varying nitrate concentrations using 13C-labelling. Furthermore, vertical profiles of the sediment and porewater geochemistry, and the microbial communities (16S rRNA gene and shotgun metagenomic sequencing) were analyzed. Despite geochemical data indicating that simultaneous consumption of nitrate and methane took place at the sediment layers chosen for incubations, AOM rate…

Oxidation, efflux, and isotopic fractionation of methane during autumnal turnover in a polyhumic, boreal lake

2007

[1] We studied the oxidation and efflux of methane (CH4) in a small, polyhumic lake, Mekkojarvi (southern Finland), during 6 weeks in autumn when the stability of the water mass first weakened, temporarily restabilized, and finally mixed completely. During the summer stratification period, CH4 had accumulated in the anoxic hypolimnion to high concentrations (>150 mmol m−3). Gradual mixing of the water column during the autumn allowed access to both oxygen and CH4 by aerobic methane-oxidizing bacteria (MOB) deeper in the water column. Thus the bulk (∼83–88%) of the CH4 accumulated in the hypolimnion was subsequently consumed by MOB while only 12–17% was lost from the lake to the atmosphere a…

Preface: New challenges in anostracan research, a tribute to Graziella Mura

2017

This special volume of Hydrobiologia is dedicated to the memory of Graziella Mura, who unexpectedly passed away on 23 March 2016 when she was still carrying out her highly influential and worldrenowned research on Anostraca. She provided outstanding contributions to the current knowledge of the taxonomy and ecology of this distinctive crustacean group over the last 45 years. This volume is a tribute to her and her role in anostracan research by the community of anostracan specialists.

Occurrence of two rare species from order Lampriformes: Crestfish Lophotus lacepede (Giorna, 1809) and scalloped ribbonfish Zu cristatus(Bonelli, 181…

2017

The bony fish Lophotus lacepede (Giorna, 1809) and Zu cristatus (Bonelli, 1819) are the two species rarely recorded within the Mediterranean basin, usually reported as accidentally captured in depth (mesopelagic) fishing operations. In the current work, we present the first record of L. lacepede and Z. cristatus in fishing catches from southwestern Tyrrhenian Sea. Moreover, in order to improve existent biological/ ecological knowledge, some bio-related aspects such as feeding aspect, sexual maturity and age estimate have been discussed.

Reproductive strategy as a piece of the biogeographic puzzle: a case study using Antarctic sea stars (Echinodermata, Asteroidea)

2017

13 pages; International audience; AimTo describe and analyse asteroid biogeographic patterns in the Southern Ocean (SO) and test whether reproductive strategy (brooder versus broadcaster) can explain distribution patterns at the scale of the entire class. We hypothesize that brooding and broadcasting species display different biogeographic patterns.LocationSouthern Ocean, south of 45 °S.MethodsOver 14,000 asteroid occurrences are analysed using bootstrapped spanning network (BSN), non-metrical multidimensional scaling (nMDS) and clustering to uncover the spatial structure of faunal similarities among 25 bioregions.ResultsMain biogeographic patterns are congruent with previous works based on…

Effectiveness of Posidonia oceanica biotic indices for assessing the ecological status of coastal waters in the Saronikos Gulf (Aegean Sea, Eastern M…

2017

Biotic indices are considered key assessment tools in most national and European policies aimed at improving the quality of coastal waters. At present, several Water Framework Directive (WFD)-compliant biotic indices based on the marine angiosperm Posidonia oceanica have been developed and applied in the Mediterranean Sea. In this study, we investigated the effectiveness of four different P. oceanica indices (POMI, PREI, Valencian CS, and BiPo) in evaluating the ecological status of coastal waters in a case study area of Greece. The evaluation, comparison, and validation of the Ecological Status Class (ESC) assessments obtained by each index were based on a set of eight common sites that en…

A global perspective on the climate‐driven growth synchrony of neighbouring trees

2020

2 .pdf files: File 1. Author's article final version, Post-Print (19 Pags.- 4 Figs.- 2 Tabls.). File 2. Supplementary Materials (3 Figs.- 2 Tabls.- 1 Model Equation).

Охрана, экология и этология животных

1986

В сборнике представлены материалы по фаунистическому составу, рас­пространению и экологии редких видов животных, а также видов, имеющих хозяйственное значение, даются рекомендации по увели­чению численности редких животных.

The bioremediation potential of the Priolo Harbour (SR, Italy): isolation, identification and catabolic ability of hydrocarbonoclastic bacteria

2013

The petrochemical site of Priolo-Augusta-Melilli (Sicily, Italy), is a Site of National Interest (SIN) due to high levels of contamination of the coastline and its remediation is urgently needed. Successful remediation strategies relying on the catabolic potential of marine hydrocarbonoclastic bacteria (HCB) have been described. HCB are specialised hydrocarbon (HC)-degrading marine bacteria that use HC almost exclusively as unique carbon and energy source and become dominant in oil-impacted environments. In order to identify the key hydrocarbon degraders and explore the natural bioremediation potential of the contaminated area, sediment cores and sea water were collected inside the Priolo H…

Response of seagrasses and marine biofilms to natural acidification at CO2 vents

Nel corso degli ultimi 200 anni, circa il 30% delle emissioni antropogeniche di CO2 nell’atmosfera sono state assorbite dagli oceani, provocando un abbassamento medio dei livelli di pH oceanici pari a circa 0.1 unità. Questo fenomeno, noto come acidificazione degli oceani, sta determinando conseguenze negative sugli ecosistemi marini e sul loro funzionamento. Le attuali proiezioni climatiche suggeriscono che, in futuro, i cambiamenti climatici continueranno e si intensificheranno se non verranno adottate efficaci misure di mitigazione. Riuscire a valutare la risposta degli ecosistemi marini ai cambiamenti climatici costituisce una vera sfida per la ricerca scientifica, non solo per la diffi…