Physical habitat and water chemistry changes induced by logging and gold mining in French Guiana streams

Thumbnail
Résumé

Understanding the effects of disturbances on the physical-chemical quality of ecosystems is a crucial step to the development of ecosystem assessment tools. 95 sampling sites distributed among 4 categories of disturbance, i.e.: reference, logging, formerly and currently gold mining, were characterized using stream physical and chemical variables. Our hypotheses were: (i) logging and gold mining activities primarily affect the physical habitat structure of streams and (ii) both have an effect on chemical environments through nutrient and/or fine particulate resuspension. We demonstrate that physical variables describing the river bottom, and suspended solids discriminate both current and formerly gold mined sites from reference sites, while, whatever the type of impact encountered, nutrient concentrations do not prove relevant to measure human impacts. To understand distribution patterns of aquatic organism across FG, future research should thus aim at examining the match between physical-chemical and biological classifications of small streams under reference and impacted conditions.

Créateur
N. Dedieu, L. Allard, R. Vigouroux, S. Brosse, R. Céréghino.
Editeur
EDP Sciences.
Langue
Anglais
Source
https://doi.org/10.1051/kmae/2014026.
Média
Document
Mots clés indiqués par l'éditeur
neotropical steams, headwaters, reference conditions, deforestation, gold mining, cours d’eaux néotropicaux, tête de bassin, condition de référence, déforestation, orpaillage.
Thèmes BIO-PLATEAUX
Observation des milieux aquatiques (surveillance de l'environnement), Pollutions et pressions associées (contamination de l'eau et des milieux aquatiques ; focus sur le mercure et les déchets)
Enjeux principaux
Pollution and other impacts of human activities (pollution, artificialization, withdrawals), Uses (agriculture, fishing, industry, tourism and leisure, hydroelectricity, transport)
Couverture géographique
Guyane française
Date de création