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An Integrated Risk Assessment Model for the Implementation of Drought Insurance Markets in Spain
No full textWater is a key input in the production of many goods and services and under certain conditions can become a critical limiting factor with significant impacts on regional development. This is the case of many agricultural European Mediterranean basins, where water deficit during drought events is partially covered by illegal abstractions, mostly from aquifers, which are tolerated by the authorities. Groundwater overexploitation for irrigation has created in these areas an unprecedented environmental catastrophe that threatens ecosystems sustainability, urban water supply and the current model of development. Market-based drought insurance systems have the potential to introduce the necessary incentives to reduce overexploitation during drought events and remove the high costs of the drought indemnity paid by the government. This paper develops a methodology to obtain the optimum risk premium based on concatenated stochastic models. The methodology is applied to the agricultural district of Campo de Cartagena (Segura River Basin, Spain). Results show that the prices in a hypothetic competitive private drought insurance market would be reasonable and the expected environmental outcomes significant
Determination of hormonally active chlorinated chemicals in waters at sub µg/L level using stir bar sorptive extraction-liquid desorption followed by negative chemical ionization-gas chromatography triple quadrupole mass spectrometry
No full textA new analytical method has been developed for the screening, evaluation and determination of sub mu g/L concentrations of chlorinated chemicals in environmental waters. Ten different compounds included in the European water policy have been considered and determined by stir bar sorptive extraction (SBSE) followed by liquid desorption and negative chemical ionization gas chromatography coupled to triple quadrupole mass spectrometry (SBSE-LD-NCI-GC-QqQ-MS). Analyte extraction was performed using SBSE with 100mL sample volume, 5% MeOH, 10% NaCl and an extraction time of 14h of mechanized stirring, which provided best analytical recoveries. Desorption of analytes was carried out using 5mL acetonitrile (ACN) and 5min of two successive sonication steps which resulted best performance without any carry over. The method detection limits (MDL) ranged 3-22ng/L and 7-29ng/L for river waters and wastewaters respectively. The experimental recoveries for all compounds were>60% with<20% deviation in the reproducibility. Pentachloroanisole alone reported a low maximum recovery of 54% under given conditions. Matrix influenced signal enhancement was observed more in case of triclosan, which was managed by using matrix matched calibration standards apart from using double helix injection liner. This method was applied to the analysis of different river waters and wastewater effluent samples collected from Alcala de Henares, Spain. Four compounds namely chloropyriphos-ethyl, triclosan, -endosulfan and endosulfan sulphate were positively identified in river waters and three compounds viz., chloropyriphos-ethyl, -endosulfan and endosulfan sulphate were detected in wastewater effluents. The concentrations of -endosulfan ranged between 11.3-22.9ng/L and 16.3-33.8ng/L in river waters and wastewaters respectively. Almost 40% of the water samples analysed showed much higher concentrations of -endosulfan than prescribed European environmental quality standard limit for surface waters of 5 ng/L
Wastewater treatment method. Método de tratamiento de aguas residuales
No full textThe invention relates to a wastewater treatment method comprising: filling a container of a treatment device with a biocompatible bed of electrically conductive inert material; supplying a flow of wastewater, which flows into the container filled with the conductive biocompatible bed; and leaving the wastewater inside the container for a sufficient amount of time so that the electrons that are produced in the oxidation reactions of material transported by the wastewater are transferred to molecules also transported in the same wastewater through the conductive biocompatible bed.
Un método de tratamiento de aguas residuales comprende rellenar un recipiente contenedor de un dispositivo de tratamiento con un lecho biocompatible de material inerte conductor eléctrico, suministrar un flujo de aguas residuales que inunda el recipiente contenedor rellenado con el lecho biocompatible conductor, permaneciendo el agua residual dentro del recipiente contenedor suficiente tiempo para que los electrones, producidos en reacciones de oxidación de la materia transportada por el agua residual, sean transferidos a moléculas transportadas también en el mismo agua residual a través del lecho biocompatible conductor
First outcomes in the definition of groundwater protection zones at the Viñales National Park (Cuba) and surrounding area
No full textFate and transformation products of amine-terminated PAMAM dendrimers under ozonation and irradiation
No full textThis article deals with the degradation of a third-generation (G3) poly(amidoamine) (PAMAM) dendrimer under ozonation and irradiation. The identification and quantification of G3 PAMAM dendrimer and its transformation products has been performed by liquid chromatography-electrospray ionization-hybrid quadrupole time-of-flight-mass spectrometry. The dendrimer was completely depleted by ozone in less than 1 min. The effect of ultraviolet irradiation was attributed to hydroxyl-mediated oxidation. The transformation products were attributed to the oxidation of amines, which resulted in highly oxidized structures with abundance of carboxylic acids, which started from the formation of amine oxide and the scission of the C-N bond of the amide group. We studied the toxicity of treated mixtures for six different organisms: the acute toxicity for the bacterium Vibrio fischeri and the microcrustacean Daphnia magna, the multigenerational growth inhibition of the alga Pseudokirchneriella subcapitata, and the seed germination phytotoxicity of Licopersicon esculentum, Lactuca sativa and Lolium perenne. Ozonation and irradiation originated transformation products are more toxic than the parent dendrimer. The toxicity of the dendrimer for the green alga was linked to a strong increase of intracellular reactive oxygen species with intense lipid peroxidation. (C) 2013 Elsevier B.V. All rights reserved
Estimation of sunshine duration from the global irradiance measured by a photovoltaic silicon solar cell
No full textSunshine duration can be estimated using photovoltaic solar cells instead of conventional pyranometers or pyrheliometers, which are more expensive and therefore not suitable for low cost measurement applications in developing regions. A one-year meteorological dataset from Nicosia (Cyprus) including direct irradiance, global irradiance from a pyranometer and global irradiance from a reference PV cell was used to calculate sunshine duration following the WMO pyrheliometric method and three pyranometric methods by WMO Slob and Monna, Hinssen–Knap and Olivieri. Pyranometric algorithms were adapted to the tilted pyranometer and reference solar cell. Main results indicate that all the pyranometric algorithms underestimated sunshine duration over the span of a year in Cyprus in comparison with the reference pyrheliometric method; and that results between the pyranometer and the solar cell were comparable. The PV silicon solar cell is capable of measuring sunshine duration on a daily basis with an uncertainty similar to the obtained with a pyranometer when using the Olivieri algorithm
Design of an accurate, low-cost autonomous data logger for PV system monitoring using Arduino™ that complies with IEC standards
No full textA new data logger using the Arduino open-source electronic platform was developed to solve the current problem of monitoring photovoltaic (PV) systems at low-cost, especially in remote areas or regions in developing countries. The data logger meets all of the relevant requirements in terms of accuracy included in the International Electrotechnical Commission (IEC) standards for PV systems, with a resolution of 18-bits, including 8 analogue inputs for measuring up to 8 PV modules and/or weather sensors, 3 inputs for low-cost analogue temperature sensors and virtually unlimited inputs for digital temperature sensors. The new data logger is completely autonomous, and the prototype has achieved an initial cost of only 60 €. It was tested during a 6-month period under the harsh environmental conditions of the summer and winter in Southern Spain. The results using both the sensors and silicon reference cells indicate that the new system is reliable and exhibits comparable performance to commercial systems. This data logger is of special interest for both solar energy research and applications in developing countries, as it is both open-source and flexible. The data logger can be customised for the specific needs of each project at low-cost. The details of the specific design and its implementation are described
Treating municipal wastewater through a vegetation filter with a short-rotation poplar species
No full textThe performance of a vegetation filter using a short-rotation coppice of poplars was evaluated over a 3-year period in terms of pollutant removal capacity. The vegetation filter was designed for scattered and small populations with no storage facilities and a wastewater application constrained by the own production of effluent. Wastewater effluent was pre-treated in an Imhoff tank and applied to the vegetation filter. The chemical compositions of drainage water and groundwater were regularly monitored. Surface soil samples at the beginning and the end of the study were also collected. The monitored chemical species in drainage water and groundwater were DOC, COD, NT, NO3–N, NH4–N, PT, PO4-P, and other major ions. Electrical Conductivity, organic matter content (%), NO3–N, available P, cation exchange capacity and major cations were analysed for soil. The vegetation filter presented efficient
removal of wastewater-originated pollutants. DOC and COD removal reached values of 85%. A correlated increase in soil organic matter content was detected (from 1.0% to almost 2.8%). A similar removal capacity was observed for PT which is interpreted as due to plant uptake mechanisms and PO43� precipitation in the presence of soil Ca2+. Around 73% of NT was removed. However, due to the high applied NT load, the average NT concentration in drainage water was about 41.9 mg/L, higher than the admissible concentration limit. When considering NT mass, about 10% of the cumulative applied NT leached through the vadose zone. Groundwater quality was not affected by the vegetation
filter operation