Metals in sediment of Spanish reservoirs (Catalonia region) in a trophic gradient: spatial and temporal heterogeneity and ecotoxicology

• Grant number: 11/02954-6
• Support Opportunities: Scholarships abroad - Research
• Start date: September 01, 2011
• End date: August 28, 2012
• Field of knowledge: Engineering - Sanitary Engineering - Environmental Sanitation
• Principal Investigator: Marcelo Luiz Martins Pompêo
• Grantee: Marcelo Luiz Martins Pompêo
• Host Investigator: María Pilar López Laseras
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Universitat de Barcelona (UB), Spain

Abstract

The sediments are very important in aquatic ecosystem, since they are the final destiny of many compounds that enter in the water body, constituting a concentrated pool of these substances. Besides, the understanding of sediment dynamics (structure, function and heterogeneity) enables the understanding of important aspects of the water mass dynamics. This project aims the study of seven reservoirs located in the Cataluña region (Spain), a very developed region, with many environmental problems, which reflect in the water quality. La Llosa del Cavall, La Baells, Sant Pon, Santa Fe, Susqueda, Salt and Foix Reservoirs have similar geological tipology, but they have a trophic gradiente, varying from oligotrophic (La Llosa del Cavall) to hypereutrophic (Foix). Due to the relevance of the sediment for aquatic ecosystems and the strategic importance of this region, it is necessary to perform an assessment of the toxic potential of these sediments and its relationship with the trophy degree. This research is also part of works carried out by "Grupo de Investigación de excelencia de la Generalitat de Catalunya en Dinámica Fluvial" (FLUMEN) coordinated by Dr. Juan Armengol Bachero (Depto. de Ecologia, Facultat de Biologia, Universitat de Barcelona, Spain). In particular, this work will be supervised by Dr. Pilar López Laseras, member of the FLUMEN. This research aims: (a) to verify possible existence of spatial variation of acid volatile sulfide (AVS) content in sediment of seven Spanish Reservoirs (Cataluña region), (b) as well as the simultaneously extracted metals (SEM); and (c) check the relationship of water mass trophy level with the metal determined in water and the sediment. In each reservoir, sediment (superficial) and water mass (profile) will be sampled in four stations along the principal axis of the reservoir, in two periods It is expected higher metal concentrations in reservoirs with higher trophy degree. Regardless of the trophy degree, we expect to find a metal gradient from upper do lower portions of the reservoir. More eutrophic reservoirs have a tendency to produce higher quantities of organic matter and to present more organic sediment. The high levels of organic matter and sulfide suggest lower availability of metals and therefore, lower toxicity potential. I also expect that the experience abroad with this pos-doc proposal, and the contact with researchers at FLUMEN enable the contribution of a larger and better knowledge of ecological matters on reservoirs; the similarity among those reservoirs in Spain and from Sao Paulo Metropolitan Area might represent an starting point for the proposal of management and control solutions, aiming a better water quality. (AU)