Molecular field analysis of trophic relationships in soil-dwelling invertebrates to identify mercury, lead and cadmium transmission through forest ecosystems.
Mol Ecol
; 23(15): 3755-66, 2014 08.
Article
em En
| MEDLINE
| ID: mdl-24138157
ABSTRACT
Contamination pathways in complex food chains in soil ecosystems can be difficult to elucidate. Molecular analysis of predator gut content can, however, rapidly reveal previously unidentified trophic interactions between invertebrates and thereby uncover pathways of pollutant spread. Here, we measured concentrations of the toxic metals lead, cadmium and mercury in carabid beetle predators and their prey. Invertebrates were sampled at one control and four heavy metal-polluted sites to reveal the impact of diet composition and seasonal variation in prey availability on metal burden in carabids and metal transfer pathways through forest ecosystems. This is the first report, to our knowledge, of carabid diet composition based on PCR analysis of gut contents at the forest community level, rather than in cultivated fields. Extensive screening using group- and species-specific primers revealed that carabids ate primarily earthworms and slugs, as well as smaller numbers of woodlice and springtails. Metal concentrations in carabids correlated with seasonal changes in diet. Mercury accumulated in beetle predators more than in their slug prey. As earthworms, slugs and carabid beetles are the major prey of many birds and mammals, prey-predator transfer and associated toxicity are major risks at mercury-contaminated sites. Carabids may be useful bioindicators for assessing the impact of pollutants on soil ecosystems, as long as species and seasonal factors are taken into account.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Solo
/
Besouros
/
Cádmio
/
Cadeia Alimentar
/
Chumbo
/
Mercúrio
Tipo de estudo:
Prognostic_studies
Limite:
Animals
País/Região como assunto:
Europa
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article