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3D Virtual Itinerary in the Geological Heritage from Natural Areas in Salamanca-Ávila-Cáceres, Spain
No full textFrom a large database generated from the geological heritage of more than 100 geosites in four natural areas of Salamanca, Ávila, and Cáceres provinces (Spain), the 13 most representative sites were selected, and their scientific, educational, and tourist/cultural interest values were determined. The natural park of Batuecas-Sierra de Francia-Candelario presents the highest values and is followed by the natural park of Arribes del Duero. Using geomatic tools, digital information was compiled from different thematic layers, and, together with photographs, diagrams, and descriptive cards, was incorporated to produce didactic resources. By interacting with digital information using the free Google Earth platform, 3D virtual flights, which can be followed in real time, were established and implemented in different formats (mpeg, avi, wma, etc.). These are reproducible in different multimedia systems, which increases the possibility of educational and tourism use by broad layers of the population. Therefore, this favors the sustainable development of the area
Combining eight research areas to foster the uptake of ecosystem-based management in fresh waters
No full textIdentification of contaminants of concern in the upper Tagus river basin (central Spain). Part 2: Spatio-temporal analysis and ecological risk assessment
No full textThis study provides a description of the water quality status in the tributaries of the upper Tagus River and a preliminary risk assessment for freshwater organisms. A wide range of physico-chemical parameters, nutrients, metals and organic contaminants (20 pesticides, and 32 point source chemicals, mainly pharmaceuticals) were monitored during spring, summer and autumn of 2016. Monitoring of organic contaminants was performed using conventional grab sampling and passive samples (POCIS). The variation of the different groups of parameters as regards to land use and sampling season was investigated. The prioritization of organic and inorganic contaminants was based on the toxic unit (TU) approach, using toxicity data for algae, invertebrates and fish. Finally, the compliance with the Environmental Quality Standards (EQS) set as part of the Water Framework Directive (WFD) was evaluated for the listed substances. This study shows that the land use characteristics had a large influence on the spatial distribution of the contaminants and other water quality parameters, while temporal trends were only significant for physico-chemical parameters, and marginally significant for insecticides. Acute toxicity is likely to occur for some metals (copper and zinc) in the most impacted sites (TU values close to or above 1). Low acute toxicity was determined for organic contaminants (individual compounds and mixtures) on the basis of grab samples. However, the assessment performed with POCIS samples identified diuron, chlorpyrifos and imidacloprid as potentially hazardous compounds. Several contaminant mixtures that may cause chronic toxicity and that should be considered in future regional chemical monitoring plans were identified. Our study also shows that some metals and pesticides exceeded the WFD regulatory thresholds and that only 30% of the sampled sites had a good chemical status. Further research is needed to identify chemical emission sources and to design proper abatement options in the Tagus river basin
Predictive Models in Ecotoxicology: Bridging the Gap Between Scientific Progress and Regulatory Applicability—Remarks and Research Needs
No full textThis paper concludes a special series of 7 articles (4 on toxicokinetic–toxicodynamic [TK–TD] models and 3 on
quantitative structure-activity relationship [QSAR] models) published in previous issues of Integrated Environmental
Assessment and Management (IEAM). The present paper summarizes the special series articles and highlights their
contribution to the topic of increasing the regulatory applicability of effect models. For both TK–TD and QSAR approaches,
we then describe the main research needs. The use of TK–TD models for describing sublethal effects must be better
developed, particularly through the improvement of the dynamic energy budget (DEBtox) approach. The potential of TK–
TD models for moving from lower (molecular) to higher (population) hierarchical levels is highlighted as a promising
research line. Some relevant issues to improve the acceptance of QSAR models at the regulatory level are also described,
such as increased transparency of the performance assessment and of the modeling algorithms, model documentation,
relevance of the chosen target for regulatory needs, and improved mechanistic interpretabilit
Use of an analytical hierarchy process for the selection of adequate desalination technologies for Spain and the Gulf Cooperation Council
No full textVarious countries worldwide are known to face water scarcity problems. Seawater desalination is one of the solutions used to solve water scarcity issues in Spain and the Gulf Cooperation Council (CCC) states. These countries use three main water desalination technologies, namely, multi-effect distillation, multi-stage flash (MSF) and reverse osmosis (RO) desalination. Several factors must be considered to choose the most appropriate desalination technology for each country. In this paper, the analytical hierarchy process was employed to select adequate desalination technologies for Spain and the GCC countries by considering results obtained from a survey of experts in the field. This study found that the most suitable technologies for Spain and the GCC countries are RO and MSF, respectively
Electrodes boost microbial metabolism to mineralize antibiotics in manure
No full textLivestock manures are potential sources of antibiotics in the environment. Sulfamethazine (SMZ), frequently used in veterinary medicine, can enter the environment by using manure as soil fertilizer due to its incomplete absorption in the animal gut and its unmetabolized excretion. The objective of this study was to evaluate the mineralization of 14C-labelled SMZ in manure under a new redox scenario provided by microbial electrochemical reactors, termed microbial electroremediating cells (MERC). These devices aim to overcome the electron acceptor limitation in bacterial oxidative metabolism by means of using electrodes to enhance the biodegradation of pollutants in the environment. Our results revealed that the total degradation of 14C-SMZ reached 43.5% in short term batch laboratory scale experiments under reducing conditions (−400 mV vs. Ag/AgCl). Actually, SMZ mineralization was enhanced up to 10-fold in the early stages (after 2 weeks) in comparison with an electrode-free natural attenuation assay. Moreover, mineralization showed a dependence on electrode potential, with negligible results for conditions set to +400 mV vs Ag/AgCl. The impact of merging electrodes and microorganisms for manure bioremediation suggests a promising future for this emerging technology to treat polluted livestock wastes and prevent soil and groundwater pollution
Analysis of existing water information for the applicability of water quality indices in the fluvial-littoral area of turia and Jucar Rivers, valencia, Spain
No full textFor the first time, all the water quality information gathered by an European Union water district authority between 1990 and 2016 (the Spanish Jucar River Management Authority, Confederación Hidrográfica del Júcar, CHJ) was analysed and discussed. The main goal is to evaluate the applicability of this existing physicochemical information as potential data sources for continuous evaluation with Water Quality Indices (WQIs). Specifically, the spatial and temporal representativity of available data is assessed together with the applicability of WQIs both in time and space. A list of 42 existing WQIs with type and number of variables used was compiled after literature review. The study was carried out in the fluvial-littoral area of Turia and Jucar Rivers, Valencia, Spain, which was divided into six Landscape Functional Areas (LFAs), based on the outer continental perimeter zone, the irrigation areas of main channels crossing the flood plain, and the Albufera Lake.
Input information consisted of a database, provided by the CHJ, of 67 sampling points with 401 physicochemical variables from 1990 to 2016, (about 283,023 records). This information was cross-analysed using descriptive statistics to evaluate the CHJ database information, the possibility of using WQIs, and the performance of target WQIs once their possible use both in time (27 years) and space (6 LFA) was established. Finally, a map representing the six LFAs was digitised, including the 67 sampling points and their water physicochemical characteristics.
Results demonstrate that, out of 42 WQIs selected, seven can be used whenever all variables required are present. None of them can be calculated simultaneously at all stations and for all years. About 31% (21) of stations provided data that can be used in some years, and only 10% (27,430 values) of the database information is required for WQIs calculation. Indices that estimate repetitiveness (constant measure of water parameters over time) and consistency (coincidence of parameters measured at the 21 sampling points) show great disparity both in time and in parameters between sampling points. These results suggest that not only is it essential to obtain information on different compounds that may alter the water quality (to fulfil basin management authority policies), but also to establish a set of mandatory physicochemical parameters based on suitable application of some indices allowing temporary monitoring and comparison between them, in an accessible and repeatable manner
Comparative Performance of Microbial Desalination Cells Using Air Diffusion and Liquid Cathode Reactions: Study of the Salt Removal and Desalination Efficiency
No full textMicrobial Desalination Cell (MDC) represents an innovative technology which accomplishes simultaneous desalination and wastewater treatment without external energy input. MDC technology could be employed to provide freshwater with low-energy input, for example, in remote areas where organic wastes (i.e., urban or industrial) are available. In addition, MDC technology has been proposed as pre-treatment in conventional reverse osmosis plants, with the aim of saving energy and avoiding greenhouse gases related to conventional desalination processes. The use of oxygen reduction (i.e. O2 + 2H2O + 4e− → 4 OH−, E0′ = 0.815 V, pH = 7) was usually implemented as cathodic reaction in most of the MDCs reported in literature, whereas other strategies based on liquid catholytes have been also proposed, for example, ferro-ferricyanide redox couple (i.e. Fe(CN)3−6
+ 1e− → Fe(CN)4−6
, E0 = 0.37 V). As the MDC designs in the literature and operation modes (i.e., batch, continuous, semi-continuous, etc.) are quite different, the available MDC studies are not directly comparable. For this reason, the main objective of this work was to have a proper comparison of two similar MDCs operating with two different catholyte strategies, and compare performance and desalination efficiencies. In this sense, this study compares the desalination performance of two laboratory-scale MDCs located in two different locations for brackish water and sea water using two different strategies. The first strategy consisted of an air cathode for efficient oxygen reduction, while the second strategy was based on a liquid catholyte with Fe3+/Fe2+ solution (i.e., ferro-ferricyanide complex). Both strategies achieved desalination efficiency above 90% for brackish water. Nominal desalination rates (NDR) were in the range of 0.17–0.14 L·m−2·h−1 for brackish and seawater with air diffusion cathode MDC, respectively, and 1.5–0.7 L·m−2·h−1 when using ferro-ferricyanide redox MDC. Organic matter present in wastewater was effectively removed at 0.9 and 1.1 kg COD·m−3·day−1 using the air diffusion cathode MDC for brackish and sea water, respectively, and 7.1 and 19.7 kg COD·m−3·day−1 with a ferro-ferricyanide redox MDC. Both approaches used a laboratory MDC prototype without any energy supply (excluding pumping energy). Pros and cons of both strategies are discussed for subsequent upscaling of MDC technology
Effects of increased temperature, drought and an insecticide on freshwater zooplankton communities
No full textIn the present study we performed a microcosm experiment to assess the effects of the insecticide lufenuron on zooplankton communities exposed to increased temperature and drought in (semi‐)arid regions. The experiment consisted of 3 environmental scenarios, assessed in 2 parts. Firstly, we assessed how water temperature (20 and 28 °C) affects the sensitivity and resilience of the zooplankton community to lufenuron. Secondly, we investigated the influence of drought on the structure of the zooplankton community at a high water temperature (28 °C) and evaluated its possible interaction with lufenuron. The results show that the community exposed to lufenuron at 28 °C had a faster lufenuron‐related response and recovery than the community at 20 °C. The combined effects of lufenuron and temperature resulted in a synergistic effect on some taxa (Daphnia sp., Cyclopoida, and Copepoda nauplii). The tested zooplankton community had a high resilience to drought, although some particular taxa were severely affected after desiccation (Calanoida). Interactions between drought and lufenuron were not statistically significant. However, rewetting after desiccation contributed to lufenuron remobilization from sediments and resulted in a slight Cyclopoida population decline at high exposure concentrations. The study shows how environmental conditions related to global change in (semi‐)arid regions may influence chemical fate and the vulnerability of zooplankton communities to chemical stress