scholarly journals Testing the Use of Standardized Laboratory Tests to Infer Hg Bioaccumulation in Indigenous Benthic Organisms of Lake Maggiore (NW Italy)

2020 ◽  
Vol 10 (6) ◽  
pp. 1970 ◽  
Author(s):  
Davide A.L. Vignati ◽  
Roberta Bettinetti ◽  
Angela Boggero ◽  
Sara Valsecchi
Keyword(s):  
Food Webs ◽  
Quality Standard ◽  
Benthic Organisms ◽  
Lumbriculus Variegatus ◽  
Prey Fish ◽  
Top Predators ◽  
Pelagic Food Webs ◽  
Total Hg ◽  
Nw Italy ◽  
Hg Accumulation

The chronic toxicity of mercury essentially derives from its strong tendency to biomagnify along food webs. For this reason, the European regulatory framework establishes an environmental quality standard for Hg based on the total Hg concentration in prey fish to protect top predators. A considerable part of the Hg burden of prey fish can come from the ingestion of benthic organisms that, in the presence of contaminated sediments, may remobilize substantial amounts of Hg towards the pelagic food webs. The present study evaluated whether Hg accumulation in assemblages of indigenous chironomids and oligochaetes could be predicted using standardized laboratory bioaccumulation tests with Chironomus riparius and Lumbriculus variegatus. Indigenous chironomids and oligochaetes were recovered at different sites in a lake suffering from legacy Hg pollution and analyzed for total Hg content. Sediment aliquots from the same sites were used to assess Hg bioaccumulation using laboratory-reared C. riparius and L. variegatus. Mercury concentrations in indigenous versus laboratory organisms showed a good correlation (p < 0.05; Spearman correlation test) only in the case of C. riparius versus indigenous chironomids, suggesting the possibility of using linear regressions to predict Hg accumulation by these benthic invertebrates. Further research needs and caveats as to the applicability of the present results to other aquatic systems are identified and discussed.

Analyzing pelagic food webs leading to top predators in the Pacific Ocean: A graph-theoretic approach

2010 ◽  
Vol 86 (1-2) ◽  
pp. 152-165 ◽  
Author(s):  
Jeffrey M. Dambacher ◽  
Jock W. Young ◽  
Robert J. Olson ◽  
Valérie Allain ◽  
Felipe Galván-Magaña ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Food Webs ◽  
Theoretic Approach ◽  
Graph Theoretic ◽  
Top Predators ◽  
Graph Theoretic Approach ◽  
The Pacific ◽  
Pelagic Food Webs ◽  
The Pacific Ocean

The paradox of pelagic food webs in the northern Bering Sea—I. Seabird food habits

1987 ◽  
Vol 7 (8) ◽  
pp. 895-911 ◽  
Author(s):  
Alan M. Springer ◽  
Edward C. Murphy ◽  
David G. Roseneau ◽  
C. Peter McRoy ◽  
Brian A. Cooper
Keyword(s):  
Food Webs ◽  
Bering Sea ◽  
Food Habits ◽  
Northern Bering Sea ◽  
Pelagic Food Webs

Kinetics of mercury accumulation by freshwater biofilms

2017 ◽  
Vol 14 (7) ◽  
pp. 458 ◽  
Author(s):  
Perrine Dranguet ◽  
Vera I. Slaveykova ◽  
Séverine Le Faucheur
Keyword(s):  
Food Webs ◽  
Food Chain ◽  
Microbial Composition ◽  
Biofilm Thickness ◽  
Aquatic Microorganisms ◽  
Uptake Rate Constant ◽  
The Difference ◽  
Accumulation Kinetics ◽  
Kinetics Of ◽  
Hg Accumulation

Environmental contextMercury (Hg) is a major environmental contaminant due to its toxicity, accumulation and biomagnification along the food chain. We demonstrate that Hg accumulation by biofilms, one possible entry point for Hg into food webs, is rapid and depends on biofilm structure and composition. These findings have important implications for the understanding of Hg bioavailability and effects towards aquatic microorganisms. AbstractMercury contamination is of high concern due to its bioaccumulation, toxicity and biomagnification along the food chain. Biofilms can accumulate Hg and contribute to its incorporation in freshwater food webs. Nevertheless, the accumulation kinetics of Hg by biofilms is not well described and understood. The aim of the present study was thus to gain mechanistic understanding of Hg accumulation by biofilms. Kinetics of Hg uptake by biofilms of different ages (e.g. different compositions) was characterised by determining Hg contents in biofilms with and without a cysteine-washing step. Hg accumulation was rapid in both biofilms, with the uptake rate constant of the younger biofilm 10 times higher than that of the older biofilm. Moreover, accumulated Hg reached a plateau at 24h exposure in the younger biofilm, whereas it increased linearly in the older biofilm. The observed difference in Hg uptake by the studied biofilms is likely a result of the difference in biofilm thickness (and thus Hg diffusion inside the biofilm matrix) and microbial composition. These findings have important implications for the understanding of Hg bioavailability and effects towards aquatic microorganisms.

scholarly journals A description of mercury in fishes from the Madeira River Basin, Amazon, Brazil

2008 ◽  
Vol 38 (3) ◽  
pp. 431-438 ◽  
Author(s):  
Wanderley Rodrigues Bastos ◽  
Mauro de Freitas Rebelo ◽  
Márlon de Freitas Fonseca ◽  
Ronaldo de Almeida ◽  
Olaf Malm
Keyword(s):  
Body Weight ◽  
River Basin ◽  
Fish Species ◽  
Temporal Trends ◽  
Migratory Fish ◽  
Madeira River ◽  
Interspecies Variability ◽  
Total Hg ◽  
Madeira River Basin ◽  
Hg Accumulation

Over the last 20 years several projects carried on the Madeira River basin in the Amazon produced a great amount data on total Hg concentration in different fish species. In this paper we discuss temporal trends in Hg contamination and its relation to body weight in some of those fishes, showing that even within similar groups, such as carnivorous and non-migratory fish, the interspecies variability in Hg accumulation is considerable.

FISHES AS INTEGRATORS OF BENTHIC AND PELAGIC FOOD WEBS IN LAKES

Ecology ◽  
2002 ◽  
Vol 83 (8) ◽  
pp. 2152-2161 ◽  
Author(s):  
M. Jake Vander Zanden ◽  
Yvonne Vadeboncoeur
Keyword(s):  
Food Webs ◽  
Pelagic Food Webs
Sign in / Sign up

Export Citation Format

Share Document