Topic
Chamelea
About: Chamelea is a research topic. Over the lifetime, 10 publications have been published within this topic receiving 112 citations.
Papers
TL;DR: The anoxic survival time of the bivalves Chamelea gallina, Cerastoderma edule and Scapharca inaequivalvis from two different ecosystems and differing anoxia tolerances was studied in static and flow-through systems, indicating that proliferation of anaerobic pathogenic bacteria, firmly associated with the bivals, is a main cause of death.
Abstract: The anoxic survival time of the bivalves Chamelea gallina, Cerastoderma edule and Scapharca inaequivalvis from two different ecosystems and differing anoxia tolerances was studied in static (closed) and flow-through systems. The antibiotics chloramphenicol, penicillin and polymyxin were added, and molybdate (specific inhibitor of the process of sulfate reduction). Survival in (near) anoxic seawater of Chamelea was studied in a static system by comparing untreated seawater with autoclaved seawater and untreated clams with clams incubated in well-aerated seawater, containing the broad-spectrum antibiotic chloramphenicol, prior to the anoxic survival test. With untreated clams and natural seawater (median mortality time 2.4 days) a decrease in pH and exponential accumulation of sulfide and ammonium was observed in the anoxic medium, indicating excessive growth of (sulfate reducing) bacteria. In sterilized seawater LT50 (2.1 days) was not significantly different and again considerable amounts of ammonium and sulfide accumulated. However, pre-treatment of clams with chloramphenicol resulted in an increase of LT50 (11.0 days) by approximately fivefold. Accumulation of ammonium and sulfide was retarded, but was finally even stronger than in the medium containing untreated clams. Median mortality times were 2.5 and 2.4 days for Chamelea and 2.7 and 2.9 days for Cerastoderma for static and flow-through incubations, respectively. Addition of chloramphenicol increased strongly survival time in both systems with corresponding values of 11.0 and 16.3 days for Chamelea, and 6.4 and 6.5 days for Cerastoderma. LT50 of Scapharca in anoxic seawater was 14.4 days. Chloramphenicol and penicillin increased median survival time to 28.5 and 28.7 days, respectively, whereas polymyxin displayed no effect (LT50=13.6 days). Molybdate added to artificial sulfate free seawater blocked biotic sulfide formation, but did not improve survival time (LT50=13.7 days). Overall the results indicate that proliferation of anaerobic pathogenic bacteria, firmly associated with the bivalves, is a main cause of death besides lack of oxygen. Bacterial damage is probably caused by injury of the tissues of the clams and not by the release of noxious compounds to the medium.
52 citations
TL;DR: This is the first time that C .
43 citations
TL;DR: It was deduced that bivalves have developed different biogeochemical mechanisms to regulate Zn content and its chemical speciation and that cysteine plays an important role as an active part of detoxification mechanism.
Abstract: Zinc incorporation into marine bivalve shells belonging to different genera (Donax, Glycymeris, Lentidium, and Chamelea) grown in mine-polluted seabed sediments (Zn up to 1% w/w) was investigated using x-ray diffraction (XRD), chemical analysis, soft x-ray microscopy combined with low-energy x-ray fluorescence (XRF) mapping, x-ray absorption spectroscopy (XAS), and transmission electron microscopy (TEM). These bivalves grew their shells, producing aragonite as the main biomineral and they were able to incorporate up to 2.0–80 mg/kg of Zn, 5.4–60 mg/kg of Fe and 0.5–4.5 mg/kg of Mn. X-ray absorption near edge structure (XANES) analysis revealed that for all the investigated genera, Zn occurred as independent Zn mineral phases, i.e., it was not incorporated or adsorbed into the aragonitic lattice. Overall, our results indicated that Zn coordination environment depends on the amount of incorporated Zn. Zn phosphate was the most abundant species in Donax and Lentidium genera, whereas, Chamelea shells, characterized by the highest Zn concentrations, showed the prevalence of Zn-cysteine species (up to 56% of total speciation). Other Zn coordination species found in the investigated samples were Zn hydrate carbonate (hydrozincite) and Zn phosphate. On the basis of the coordination environments, it was deduced that bivalves have developed different biogeochemical mechanisms to regulate Zn content and its chemical speciation and that cysteine plays an important role as an active part of detoxification mechanism. This work represents a step forward for understanding bivalve biomineralization and its significance for environmental monitoring and paleoreconstruction.
19 citations
TL;DR: The experiments performed allow one to conclude that the impact of diesel fuel and cadmium chloride causes an induction of biochemical and cytological antistress mechanisms in the mollusk organisms.
Abstract: Concentrations of haemocytes, the ATP content in them, and the histological features of bivalves were studied under an experimental acute impact of diesel fuel and cadmium chloride, including three weeks after the displacement of the animals into pure water. To conduct the experiment, three species of Black-Sea bivalves (Anadara inaequivalvis, Mytilis galloprovincialis, and Chamelea gallina) collected in the Black Sea during cruise 79 of R/V Akvanavt in May 2005 were used. The experiments performed allow one to conclude that the impact of cadmium chloride at a concentration of 2 mg/l and of diesel fuel at a concentration of 2 ml/l for 36 hours causes an induction of biochemical and cytological antistress mechanisms in the mollusk organisms. The effect of this impact remains for three weeks. The parameters of the Anadara haemolymph studied, the content and percentage of erythrocytes, and the ATP concentration in the haemocytes may be used as biomarkers of nonspecific environmental pollution. The usage of the Chamelea and Mytilis haemolymph parameters for biotests requires further studies.
10 citations
TL;DR: Estimates of the P/B coefficient in Ch.
Abstract: Characteristics of annual production based on various mass data (whole animal mass; shell mass; and wet, dry, and ash-free dry soft tissue mass), the P/B coefficient, and specific production were estimated for the bivalve mollusk Chamelea gallinasampled from 21 localities in the northwestern and eastern Black Sea. The annual production correlated with population biomass (r= 0.994) and mean individual mass (r= – 0.737), while the P/Bcoefficient depended mainly on mean individual mass (r= – 0.719). Estimates of the P/Bcoefficient in Ch. gallinafrom the Black Sea were smaller than those of other marine invertebrates found worldwide with the same energy equivalent. Multiple linear regression equations were calculated for empirical relationships of various characteristics of annual production to the population biomass and mean individual biomass of Ch. gallina.
5 citations
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Performance Metrics
| Year | Papers |
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| 2018 | 1 |
| 2010 | 1 |
| 2007 | 1 |
| 2005 | 1 |
| 2004 | 1 |
| 2003 | 1 |