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Barcelona, Spain

Camp J.,Biologics | Flo E.,Biologics | Vila M.,Biologics | Arin L.,Biologics | And 4 more authors.
Handbook of Environmental Chemistry | Year: 2016

The Water Framework Directive (WFD) mandates the use of biological quality element (BQE) phytoplankton to assess the ecological status of coastal and transitional water bodies (WB). Here, we present (i) a critique of the general ecological assumptions of the WFD, (ii) a review of the ecological features of coastal phytoplankton dynamics, (iii) several approaches to establish a methodology to assess water-quality along the Catalan coast (NW Mediterranean Sea) based on BQE phytoplankton, and (iv) a critical examination of the use of phytoplankton as a BQE. Since 2005, we have followed several approaches aimed at assessing water-quality based on BQE phytoplankton and linking this indicator to a proxy to a costal pressure index. We have therefore studied phytoplankton communities at three different levels: as potentially harmful species, as functional or taxonomic groups, and with respect to their bloom frequency. Despite intense efforts, none of these fulfilled the WFD's management requirements, which in this context were found to contain several inherent flaws. As an alternative, we propose a methodology to assess water-quality based on the use of chlorophyll-a (Chl-a), as a proxy of phytoplankton biomass. The Chl-a concentration offers a very simple and representative measure of the phytoplankton community, and, importantly, it is used worldwide in water-quality studies, thus allowing not only regional but also cross-country comparisons. Moreover, because Chl-a concentrations clearly respond to nutrient enrichment, we were able to establish a BQE-specific typology for water bodies based on salinity, which is linked to nutrient loads. Using a newly developed coastal pressure index (Land Use Simplified Index, LUSI) that also reflects nutrient inputs, we demonstrated a significant pressure-impact relationship, as required by the WFD for management purposes. Based on this relationship, we were able to define reference conditions and water-quality boundaries for each type. We conclude our discussion with a consideration of the pros and cons of the use of phytoplankton as a BQE. © 2016 Springer International Publishing Switzerland.

Figueras M.J.,Rovira i Virgili University | De Torres M.,Catalan Water Agency Spain | Silvera C.,Rovira i Virgili University | Corrales M.J.,Catalan Water Agency Spain
Handbook of Environmental Chemistry | Year: 2016

The quality of coastal recreational waters is monitored in Europe and other geographical areas through the analysis of faecal indicator bacteria, i.e. total and faecal coliforms and more recently E. coli and intestinal enterococci as in the new EU Bathing Water Directive (2006/7/EC). The old and new indicators and their methods of analysis are presented in this chapter underlying the limitations detected for the methods included in the new Directive. The expertise achieved along the ca. 25 years of monitoring the Catalan bathing waters revealed the two factors responsible of sporadically altering the otherwise excellent water quality of our beaches. These factors are rain events and incidences of the sewerage system. The Catalan beaches have been classified on the basis of the impact that rain events may have on altering their water quality. This information is now used to provide almost real-time warnings through the recently launched mobile app. Common alteration of the water aspect such as water discolouration, phytoplankton blooms and presence of foam that may be perceived as contamination by the public showed after investigation to correspond mainly to natural phenomena. The interrelationship established with the municipalities and the developed communication systems enabled to obtain accurate timely information from each bathing area. © 2016 Springer International Publishing Switzerland.

Oliva F.,University of Barcelona | Vegas E.,University of Barcelona | Civit S.,University of Barcelona | Garrido T.,Catalan Water Agency Spain | And 2 more authors.
Handbook of Environmental Chemistry | Year: 2016

Groundwater is a valuable natural resource that needs to be assessed and protected. The European Union (EU) adopted new water legislation that includes the Water Framework Directive (WFD) and the Groundwater Daughter Directive (GWD). Both require the identification of sustained increasing pollution trends and their reversal. This is the second pillar of the WFD: such trends have to be identified for any pollutants that result in groundwater being characterized as at risk of not meeting the environmental objectives. Measuring these trends is necessary to determine and understand whether changes in land use, fertilizer application, pollution history, or climate change are affecting groundwater quality. However, in many cases, groundwater data series may not meet minimum requirements for classical statistical procedures employed in trend assessment: among other obstacles, data may be sparse, with missing or extreme values, censored data, seasonal effects, and autocorrelation. The aim of this chapter is to present and review several statistical methodologies that have been proposed and applied in recent years to deal with groundwater trend assessment, discussing the relative advantages and disadvantages of each one. © 2016 Springer International Publishing Switzerland.

Bofill-Mas S.,University of Barcelona | Rusinol M.,University of Barcelona | Fraile J.,Catalan Water Agency Spain | Garrido T.,Catalan Water Agency Spain | And 2 more authors.
Handbook of Environmental Chemistry | Year: 2016

Microbial source tracking (MST) tools are used to identify sources of faecal pollution to accurately assess public health risks and implement best management practices. Many different viruses are excreted by humans and animals and are frequently detected in water contaminated with faeces or/and urine. Because of the large degree of host specificity of each virus and the substantial stability of many excreted viruses in the environment, some viral groups are considered to be accurate MST indicators. The Laboratory of Virus Contaminants of Water and Food at the University of Barcelona has proposed the use of viral indicators as well as cost-effective methods for the concentration of viruses from water. The developed procedures have been used to determine the levels of faecal pollution in environmental samples as well as for tracing the origin of faecal contamination. Such tools were recently used by the Catalan Water Agency to identify nitrate contamination sources in groundwater. Human adenoviruses, human polyomavirus JC, porcine adenoviruses, bovine polyomaviruses, chicken/Turkey parvoviruses, and ovine polyomaviruses can be quantified in samples using molecular methods (qPCR). The selected DNA viruses specifically infect their hosts and are persistently excreted in faeces and/or urine throughout the year in all geographical areas studied. The procedures that have been developed to quantify these viruses have been applied to bathing, coastal, surface and groundwater. In this study, the source of nitrate contamination in groundwater was identified by analysing viral markers, thereby demonstrating the usefulness of the selected viruses for the identification of sources of contamination in water. This methodology can be used to provide information to guide the proper application of measures in place to protect water from pollution caused by nitrates from several sources and thus to facilitate the accurate application of the 91/676/EEC Directive, which is mainly focused on agricultural sources of water contamination. © 2016 Springer International Publishing Switzerland.

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