TY - JOUR
T1 - The usefulness of ecotoxicological tools to improve the assessment of water bodies in a climate change reality
AU - Novais, M. H.
AU - Penha, A. Marchã
AU - Catarino, A.
AU - Martins, I.
AU - Fialho, S.
AU - Lima, A.
AU - Morais, M.
AU - Palma, P.
N1 - Funding Information:
The work is co-funded by National funds through FCT – Fundação para a Ciência e Tecnologia, I.P. (projects UIDB/04683/2020 and UIDP/04683/2020). The present research is also co-funded by the European Union through the European Regional Development Fund, included in the COMPETE 2020 (Operational Program Competitiveness and Internationalization) through the ALOP project (ALT20-03-0145-FEDER-000004), and through the European Agricultural Fund for Rural Development through the FitoFarmGest Operational Group (PDR 2020-101-030926). We thank Josué Figueira for the valuable help with fieldwork. We also acknowledge the Agência Portuguesa do Ambiente I.P. / Administração da Região Hidrográfica do Alentejo (ARH Alentejo) for kindly providing the information with the surface water status classification.
Funding Information:
The work is co-funded by National funds through FCT – Fundação para a Ciência e Tecnologia , I.P. (projects UIDB/04683/2020 and UIDP/04683/2020 ). The present research is also co-funded by the European Union through the European Regional Development Fund , included in the COMPETE 2020 (Operational Program Competitiveness and Internationalization) through the ALOP project ( ALT20-03-0145-FEDER-000004 ), and through the European Agricultural Fund for Rural Development through the FitoFarmGest Operational Group ( PDR 2020-101-030926 ).
Publisher Copyright:
© 2023 The Authors
PY - 2023/11/25
Y1 - 2023/11/25
N2 - This study aimed to analyse the added value of using ecotoxicological tools to complement and improve the assessment of natural water bodies status, in situations of climate change, with a higher frequency of extreme events as floods or droughts. Four water bodies of streams in the Guadiana Basin (Álamos, Amieira, Lucefécit, Zebro) were studied in 2017 and 2018 and classified based on the Water Framework Directive (WFD) parameters: Biological Quality Element – Phytobenthos (diatoms), General chemical and physicochemical elements, Specific pollutants, and Priority Substances. Complementarily, bioassays (including lethal and sublethal parameters) were carried out with organisms of different trophic levels: (i) the bacteria Aliivibrio fischeri; (ii) the microalgae Pseudokirchneriella subcapitata; (iii) the crustaceans Daphnia magna, Thamnocephalus platyurus and Heterocypris incongruens. A classification system with 5 scores was developed, permitting to classify water bodies from non-toxic (EC50 > 100 %; growth and feeding rate > 80 %; blue) to highly toxic (EC50 < 10 %; growth and feeding rate < 10 %; red). The comparison between the classification based on the WFD parameters and on ecotoxicological endpoints showed similar results for 71 % of the samples, and significant positive Pearson correlations were detected between the diatom-based Specific Polluosensitivity Index (SPI) and EC50V.fisheri, the algae growth rate and Shannon diversity index. These results indicate that when the biological quality elements cannot be used (namely under drought or flooding conditions) the application of ecotoxicological bioassays may be a good alternative. Further, when ecotoxicological parameters were included, an increase of worse classifications (Bad and Poor) was observed, revealing an improvement in the sensitivity of the classification, mainly in presence of specific and priority substances. So, the ecotoxicological analysis appears to provide useful information regarding the potential presence of both known and unknown contaminants at concentrations that cause biological effects (even within the WFD limits), in agreement with several authors that have already suggested its use in biomonitoring.
AB - This study aimed to analyse the added value of using ecotoxicological tools to complement and improve the assessment of natural water bodies status, in situations of climate change, with a higher frequency of extreme events as floods or droughts. Four water bodies of streams in the Guadiana Basin (Álamos, Amieira, Lucefécit, Zebro) were studied in 2017 and 2018 and classified based on the Water Framework Directive (WFD) parameters: Biological Quality Element – Phytobenthos (diatoms), General chemical and physicochemical elements, Specific pollutants, and Priority Substances. Complementarily, bioassays (including lethal and sublethal parameters) were carried out with organisms of different trophic levels: (i) the bacteria Aliivibrio fischeri; (ii) the microalgae Pseudokirchneriella subcapitata; (iii) the crustaceans Daphnia magna, Thamnocephalus platyurus and Heterocypris incongruens. A classification system with 5 scores was developed, permitting to classify water bodies from non-toxic (EC50 > 100 %; growth and feeding rate > 80 %; blue) to highly toxic (EC50 < 10 %; growth and feeding rate < 10 %; red). The comparison between the classification based on the WFD parameters and on ecotoxicological endpoints showed similar results for 71 % of the samples, and significant positive Pearson correlations were detected between the diatom-based Specific Polluosensitivity Index (SPI) and EC50V.fisheri, the algae growth rate and Shannon diversity index. These results indicate that when the biological quality elements cannot be used (namely under drought or flooding conditions) the application of ecotoxicological bioassays may be a good alternative. Further, when ecotoxicological parameters were included, an increase of worse classifications (Bad and Poor) was observed, revealing an improvement in the sensitivity of the classification, mainly in presence of specific and priority substances. So, the ecotoxicological analysis appears to provide useful information regarding the potential presence of both known and unknown contaminants at concentrations that cause biological effects (even within the WFD limits), in agreement with several authors that have already suggested its use in biomonitoring.
KW - Bioassays
KW - Biotic indices
KW - Diatoms
KW - Ecotoxicological classification system
KW - Specific pollution sensitivity index
UR - http://www.scopus.com/inward/record.url?scp=85168997017&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2023.166392
DO - 10.1016/j.scitotenv.2023.166392
M3 - Article
C2 - 37597569
AN - SCOPUS:85168997017
SN - 0048-9697
VL - 901
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 166392
ER -
