Author(s): Francisco Miguel Cortes Sanchez; Beatriz Molina Martin; Maria Diaz Redondo; Javier Alvarez Rodriguez

Linked Author(s): Francisco Miguel Cortés Sánchez

Keywords: Duero; Physicochemical status; Temporal trends; Seasonality

Abstract: The assessment of the ecological and chemical status of water bodies is an essential aspect of the European water policy. The Water Framework Directive (2000/60/EC) obliges Member States to guarantee the quality and comparability of the methods used to monitor and evaluate the ecological status of the waters. In this sense, the statistical analysis of long-term time series of chemical and physicochemical parameters is presented as a fundamental tool for environmental monitoring of water quality, for the identification of pressures and threats that affect fluvial ecosystems, for the planning of adequate measures to mitigate or eliminate existing pollution and to evaluate the effectiveness of these programmes of measures based on the available scientific evidence (Bradley et al., 2015, Jung et al., 2020). The DRAINAGE project for the integral management of flood risk has among its objectives the design of a green infrastructure that is capable of mitigating the risk of flooding and in turn is compatible with the good status of the water bodies. In this context, the prior step is knowing the current ecological status and having the ability to predict the behaviour of the variables in different alternative simulation scenarios. With this knowledge available, the managers could choose the alternative that offered the best solution both in terms of flood risk and in terms of the water bodies’ status. This study proposes a methodological approach for the systematic treatment of a high volume of data, applied in this case to three water bodies in the Duero River between the cities of Toro and Zamora (Spain). Within the frame of this methodology, trends of temporal evolution and seasonality of different chemical and physicochemical water quality variables have been analysed. Also the physicochemical status, according to Spanish normative, has been evaluated. The results obtained have made it possible to identify the alteration degree of these quality elements with respect to the reference situation, which has been established due to since long-term time series were available. The beginning of the records in some parameters dates back to the year 1962. These long-term data sets represent an excellent starting point for assessing the effects of global warming and socio-economic transformations in the Duero river basin district.

DOI: https://doi.org/10.3850/IAHR-39WC2521711920221664

Year: 2022