2024-03-28T21:18:57Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1101342018-08-06T11:36:05Zcom_10261_14com_10261_8col_10261_393
Improving the WFD purposes by the incorporation of ecotoxicity tests
Roig, Neus
Sierra, Jordi
Nadal, Martí
Moreno-Garrido, Ignacio
Nieto, Elena
Hampel, Miriam
Blasco, Julián
Schuhmacher, Marta
Domingo, José L.
Ministerio de Economía y Competitividad (España)
Trabajo presentado en la 4th SCARCE International Conference (Towards a better understanding of the links between stressors, hazard assessment and ecosystem services under water scarcity), celebrada en Cádiz el 25 y 26 de noviembre de 2013.
The approval of the European Water Framework Dir ective (WFD) supposed a big step regarding aquatic ecosystems protection. According to this Directive, assessment of ecological status is based on three quality elements: biological, physicoc hemical and hydromorphological, but ecotoxicological status is still not included. Some studies have observed that biol ogical status is not always in coherence with physicochemical status, maybe due to the adaptati on mechanisms of aquatic organisms under chronic chemical exposure. In these situations, ecotoxicity t ests could be useful to obtain a better characterisation of these specific ecosystems.
The general aim of this work is to add a battery of
ecotoxicity tests to the
current analyses defined by
WFD in order to obtain a better ecological characteriza
tion of freshwater systems. The specific aims of
this work are: (1) to compare the
effectiveness and viability of differen
t ecotoxicity tests performed with
freshwater sediments (directly and with pore water) ta
king as target organisms different aquatic species,
and (2) to evaluate the relationship between stream
pollutants concentrations (organic pollutants and
metals), biological and hydromorphological status and
sediments ecotoxicity. For this purpose, thirteen
sampling sites within the Ebro river watershed were
selected. Data about priority pollutants in water,
sediment and fish as well as biological and hydromor
phological status of each sampling point will be
achieved. Moreover, in each sampling reach, composite
samples of sediment were collected by using a
Van Veen grab. Sediment samples were stored
at 4ºC prior to the ecotoxicity analyses
The ecotoxicity of pore water was evaluated by different bioassays (
Vibrio fischeri, Pseudokirshneriella
subcapitata
and
Daphnia magna
) while the ecotoxicity of wh
ole sediment was evaluated in
Vibrio
fischeri, Nitzschia palea
and
Chironomus riparius
In addition, the concentration of total heavy metals and
metal bioavailability was calculated by a sequential
extraction according to the Community Bureau of
Reference (BCR) method. To distinguish the potentially
toxic fraction associated to heavy metals burden
of sediments, an analysis of acid-volatile sulphide
(AVS) and simultaneously extracted metals (SEM) was
performed. Complementary sediment variables as humi
dity, porosity, percentages of fines (<63 μm)
organic carbon and organic
matter were determined.
This study expect to demonstrate that the integr
ation of chemical, biological and ecotoxicological
analyses could be crucial to unde
rstand the hazard of pollutants in
aquatic ecosystems, especially, in
freshwater sediments. Future research in this area is
needed in order to obtain more data and be able to
establish a tree decision of freshwater analyses ev
aluation. The poster will present the methodology
purposed for this study as well as the first prelim
inary results obtained from ecotoxicity tests.
2015-02-03T12:07:02Z
2015-02-03T12:07:02Z
2013-11
2015-02-03T12:07:02Z
póster de congreso
4th SCARCE International Conference (2013)
http://hdl.handle.net/10261/110134
http://dx.doi.org/10.13039/501100003329
eng
openAccess