The river channel pattern of the upper Paraná River is anabranching type, composed of multi-channel divided by vegetated islands. These islands are important records of environmental and climate events in the last few thousand years (late Pleistocene and Holocene), highlighting the Bandeirantes and Grande Islands. Aiming to understand the formation environments of these islands we analyzed the quantification and qualification of phytoliths and sponge spicules in complement the occurrence of frustules of diatoms, without specific identification. Studies have shown that Bandeirantes island was originated by formation of a ?lake island?, the analyzes of the proxy indicators allowed us to define five formation phases: i) first the central bar formation phase, recorded since the Late Pleistocene (14,620 years cal. BP) with the deposition of Podostemaceae phytoliths type; ii) first transitional phase without the deposition of microfossils; iii) pond phase characterized by the formation of spongofacies composed predominantly by the species Tubella variabilis and Radiospongilla amazonensis, with the preservation of large amounts of frustules, whole diatoms and phytoliths of herbaceous plants; iv) second transitional phase demonstrates that this lake system has undergone gradual clogging since 1220 years cal. BP; v) at least occurs an lowland phase which is characteristic of the current environment. The Grande Island core demonstrates that its formation took place differently than Bandeirantes Island, the scientific literature produced about the study area so far has shown that it was originated through the cut plain. The analysis of phytoliths assemblies, sponge spicules and diatomaceous frustules allowed us the definition of three formation phases: i) central bar phase recorded since 12,425 years cal. BP with the deposition of Podostemaceae phytoliths type; ii) flood plain phase with micropaleontology characteristics refering to the conditions of sediment remobilization; iii) finally levee phase characterized by deposition of phytoliths from grasses and shrubs, associated with sedimentary facies indicative of flood deposits, showing the development of a levee before 2573 years cal. BP as a result of the clipping of the floodplain by channel avulsion. | O padrão de canal fluvial do alto rio Paraná é do tipo anabranching, composto por múltiplos canais divididos por ilhas vegetadas. Tais ilhas são importantes registros dos eventos ambientais e climáticos ocorridos nos últimos milhares de anos (Pleistoceno Tardio e Holoceno), com destaque para as ilhas Bandeirantes e Grande. Para compreender as características dos diferentes ambientes de formação dessas ilhas, analisou-se a quantificação e qualificação de fitólitos e espículas de esponja aliado à ocorrência de frústulas de diatomáceas, estas por sua vez sem identificação específica. Estudos mostraram que a ilha Bandeirantes no setor analisado originou-se por formação de ilha lago, as análises dos indicadores proxy possibilitaram a definição de cinco fases de formação: i) primeiramente a fase de formação de barra central registrada desde o Pleistoceno Tardio (14.620 anos cal. AP.) com a deposição de fitólitos tipo Podostemaceae; ii) fase de transição I que não favoreceu a deposição de microfósseis; iii) fase de lagoa caracterizada pela formação de espongofácies composta predominantemente pelas espécies Tubella variabilis e Radiospongilla amazonenses, em conjunto com a preservação de grande quantidade de frústulas de diatomáceas inteiras e fitólitos de plantas herbáceas; iv) fase de transição II demonstra que este sistema lacustre sofreu paulatina colmatagem desde 1.220 anos cal. AP.; v) fase de várzea que é característica do ambiente atual. O testemunho da ilha Grande indica que sua formação deu-se de modo diferente do observado na ilha Bandeirantes, a literatura cientifica produzida na área até o momento, mostra que a mesma se originou por meio do recorte da planície. As análises das assembleias de fitólitos, espículas de esponjas e frústulas de diatomáceas possibilitaram a definição de três fases de formação: i) fase de barra central registrada desde 12.425 anos cal. AP. com a deposição de fitólitos tipo Podostemaceae; ii) fase de planície de inundação na qual as características micropaleontológicas remetem à condições de remobilização sedimentar; iii) fase de dique marginal caracterizada pela deposição de fitólitos de plantas herbáceas e arbustivas, associadas a fácies sedimentares indicativas de depósitos de inundação, evidenciando o desenvolvimento de um dique marginal antes de 2.573 anos cal. AP. em consequência do recorte da planície de inundação por avulsão do canal. | Masters

In this work, the performances of novel nano-filtration (NF) and low-pressure reverse osmosis (RO) polymeric membranes were examined with the aim of recovering the iron used as catalyst in former secondary treatment based on the Fenton-like advanced oxidation of olive mill wastewater (OMW). Results highlight that both membranes exhibit a good performance towards the rejection of iron (99.1% for the NF membrane vs. 100% for the low-pressure RO membrane) in the secondary-treated OMW effluent, thus permitting the recovery of iron in the concentrate stream in order to recycle it back into the oxidation reactor to reduce catalyst consumption. Finally, the permeate streams could be re-used for irrigation. Major productivity was observed by the selected NF membrane, about 47.4 L/hm2 upon 9 bar, whereas 30.9 L/hm2 could be yielded with the RO membrane under an operating pressure of 8 bar. Moreover, a sensibly lower fouling index was measured on the NF membrane (0.0072 in contrast with 0.065), which ensures major steady-state performance on this membrane and a longer service lifetime. This also results in lower required membrane area and membrane plant over dimension (4 modules in case of RO operation whereas only 2 modules for NF). | En este trabajo, se examinó el rendimiento de membranas modernas de nanofiltración (NF) y ósmosis inversa (OI) poliméricas con el objetivo de recuperar el hierro utilizado como catalizador en un tratamiento secundario previo de agua residual oleícola (OMW) basado en oxidación avanzada tipo Fenton. Los resultados ponen de relieven que ambas membranas exhiben buen rendimiento en cuanto al rechazo de hierro (99.1 % para la membrana de NF vs. 100 % para la membrana de OI de bajas presiones) en el efluente oleícola tras tratamiento secundario, permitiendo en consecuencia la recuperación de hierro en la corriente de concentrado para su recirculación de nuevo al reactor de oxidación para reducir el consumo de catalizador. Finalmente, las corrientes de permeado podrían ser reutilizadas para riego. Por otro lado, la productividad asegurada por la membrana de NF seleccionada fue mayor, en torno a 47.4 L/hm2 a 9 bar, mientras que 30.9 L/hm2 pudieron ser producidos por la membrana de OI bajo una presión operativa de 8 bar. Además, un índice de fouling sensiblemente menor fue medido en la membrana de NF (0.0072 en contraste con 0.065), lo que asegura mayor rendimiento en estado estacionario para esta membrana, y mayor vida de servicio. Además, ello también resultó en una menor área de membrana y sobredimensionamiento de la planta requeridas (4 módulos en caso de OI mientras que sólo para NF).

An innovative mode of groundwater recharge to a buried esker aquifer is considered. The current conceptual model affords a natural safeguard to underlying aquifers from the overlying muds. A hypothesis of groundwater recharge to a buried esker aquifer via preferential pathways across its overlying muds is tested here by heuristic numerical one-dimensional and two-dimensional modeling simulations. The hypothesis has been tested against two other conventionally accepted scenarios involving: (1) distal esker outcrop areas and (2) remote shallow-bedrock recharge areas. The main evidence comes from documented recharge pressure pulses in the overlying mud aquitard and in the underlying esker hydraulic-head time series for the Vars-Winchester esker aquifer in Eastern Ontario, Canada. These perturbations to the potentiometric surface are believed to be the aquifer response to recharge events. The migration rate of these pressure pulses is directly related to the hydraulic diffusivity of the formation. The measured response time and response amplitude between singular radar precipitation events and well hydrographs constituted the heuristic model calibration targets. The main evidence also includes mud-layering deformation (water escape features) which was observed in seismic surveys of the over-esker muds. These disturbed stratigraphic elements provide a realistic mechanism for migrating water to transit through the muds. The effective hydraulic conductivities of these preferential pathways in the muds were estimated to be between 2 × 10⁻⁶ and 7 × 10⁻⁶ m/s. The implications of these findings relate to the alleged natural safeguard of these overlying muds.

The Regional Deep Cretaceous Aquifer (RDCA) is the principal groundwater resource in Syria. Isotope and hydrochemical data have been used to evaluate the geographic zones in terms of renewable and non-renewable groundwater and the inter-relation between current and past recharge. The chemical and isotopic character of groundwater together with radiometric ¹⁴C data reflect the existence of three different groundwater groups: (1) renewable groundwater, in RDCA outcropping areas, in western Syria along the Coastal and Anti-Lebanon mountains. The mean δ¹⁸O value (−7.2 ‰) is similar to modern precipitation with higher ¹⁴C values (up to 60–80 pmc), implying younger groundwater (recent recharge); (2) semi-renewable groundwater, which is located in the unconfined section of the RDCA and parallel to the first zone. The mean δ¹⁸O value (−7.0 ‰) is also similar to modern precipitation with a ¹⁴C range of 15–45 pmc; (3) non-renewable groundwater found in most of the Syrian interior, where the RDCA becomes confined. A considerable depletion in δ¹⁸O (−8.0 ‰) relative to the modern rainfall and low values of ¹⁴C (<15 pmc) suggest that the large masses of deep groundwater are non-renewable and related to an older recharge period. The wide scatter of all data points around the two meteoric lines in the δ¹⁸O-δ²H diagram indicates considerable variation in recharge conditions. There is limited renewable groundwater in the mountain area, and most of the stored deep groundwater in the RDCA is non-renewable, with corrected ¹⁴C ages varying between 10 and 35 Kyr BP.

The aim was to study density-driven groundwater flow and analyse groundwater mixing because of seasonal changes in groundwater temperature. Here, density-driven convection in groundwater was studied by numerical simulations in a subarctic climate, i.e. where the water temperature was <4 °C. The effects of soil permeability and groundwater temperature (i.e. viscosity and density) were determined. The influence of impermeable obstacles in otherwise homogeneous ground was also studied. An initial disturbance in the form of a horizontal groundwater flow was necessary to start the convection. Transient solutions describe the development of convective cells in the groundwater and it took 22 days before fully developed convection patterns were formed. The thermal convection reached a maximum depth of 1.0 m in soil of low permeability (2.71 · 10⁻⁹ m²). At groundwater temperature close to its density maximum (4 °C), the physical size (in m) of the convection cells was reduced. Small stones or frost lenses in the ground slightly affect the convective flow, while larger obstacles change the size and shape of the convection cells. Performed simulations show that “seasonal groundwater turnover” occurs. This knowledge may be useful in the prevention of nutrient leakage to underlying groundwater from soils, especially in agricultural areas where no natural vertical groundwater flow is evident. An application in northern Sweden is discussed.

One way to see a change in environmental process is the use of appropriate parameters to tell us before and after these processes. With this we address primarily the study of climate change, particularly in coastal areas. Therefore, we have established a base of quality parameters of seawater coastline in order to evaluate the possible relation to climate change and its effects on marine environments in the Pacific and the Caribbean, the Isthmus of Panama. Therefore, samples of coastal seawater at Galeta, Playa Teta, Playa Hermosa and Playa La Marinera, four times a year, twice per season since 2013. These samples were analyzed by physical, chemical and microbiological parameters, following standard methodologies. The results allow carrying out a descriptive analysis of the coastal marine water quality sampling at each site on a given time and space. We conclude that there exists a possible link between the coastal marine water quality and the influence of climatic conditions on the concentration of the parameters and their seasonal pattern in the Pacific and Caribbean coasts of Panama. This study allows to establish a long-term research that contributes to scientific knowledge about water quality off the coast of Panama, promoting new research on these ecosystems and allowing to know the vulnerability to which they are exposed to prevent and mitigate the possible effects of climate change. | Una de las formas de ver un cambio en un proceso ambiental, es la utilización de parámetros adecuados que nos indiquen un antes y un después de estos procesos. Con esto abordamos principalmente el estudio del cambio climático, específicamente en zonas costeras. Por ello, se ha establecido una línea base de parámetros de calidad de agua marina costera con el fin de evaluar la posible relación con el cambio climático y sus efectos sobre los ambientes marinos en las costas del Pacífico y el Caribe del istmo de Panamá. Por consiguiente, se colectaron muestras de aguas marinas costeras en Punta Galeta, Playa Teta, Playa Hermosa y Playa La Marinera, cuatro veces al año, dos veces por temporada desde el año 2013. Estas muestras fueron analizadas según parámetros físico-químicos y microbiológicos, siguiendo metodologías estandarizadas. Los resultados obtenidos permiten la realización de un análisis descriptivo de la calidad del agua marina costera en cada sitio de muestreo en un tiempo y espacio determinado. Se concluye que sí existe una posible relación entre la calidad del agua marina costera y la influencia de las condiciones climáticas sobre la concentración de los parámetros y su comportamiento estacional en las costas del Pacífico y Caribe de Panamá. Este estudio permite establecer una investigación a largo plazo que contribuye al conocimiento científico sobre la calidad del agua en las costas de Panamá, impulsando nuevos estudios de investigación sobre estos ecosistemas y permitiendo conocer la vulnerabilidad a la que están expuestas para prevenir y mitigar los posibles efectos del cambio climático.

The thermal profile of a streambed is affected by a number of factors including: temperatures of stream water and groundwater, hydraulic conductivity, thermal conductivity, heat capacity of the streambed, and the geometry of hyporheic flow paths. Changes in these parameters over time cause changes in thermal profiles. In this study, temperature data were collected at depths of 30, 60, 90 and 150 cm at six streambed wells 5 m apart along the thalweg of Little Kickapoo Creek, in rural central Illinois, USA. This is a third-order low-gradient baseflow-fed stream. A positive temperature gradient with inflection at 90-cm depth was observed during the summer period. A negative temperature gradient with inflection at 30 cm was observed during the winter period, which suggests greater influence of stream-water temperatures in the substrate during the summer. Thermal models of the streambed were built using VS2DHI to simulate the thermal profiles observed in the field. Comparison of the parameters along with analysis of temperature envelopes and Peclet numbers suggested greater upwelling and stability in temperatures during the winter than during the summer. Upwelling was more pronounced in the downstream reach of the pool in the riffle and pool sequence.

The Technical University of Cotopaxi with coordination to Agricultural Engineering Career and Researching Direction carried out the kraft papper obtainment process which had two day process from the moment the fiber gets wet to improve its characteristics and softeness after the cooking process, liquefied, sheet formation, pressing and drying. Two outstanding treatments were obtained on the investigation that meet the physical ranges by 1 429 INEN regulation. As the treatment case is: t7 (Sisalana agave fiber, calcium carbonate, chlorine dioxide). Meet with the indicators and objectives. | La Universidad Técnica de Cotopaxi en coordinación con la Dirección de Investigación y la Carrera de Ingeniería Agroindustrial. Realizó el proceso de obtención de papel kraft, el cual tuvo un proceso de dos días, desde el momento en que se humecta a la fibra para mejorar sus características y suavizarla, consiguiente al proceso de cocción, licuado, formación de la hoja, prensado y secado. Se obtuvieron dos tratamientos sobresalientes en la investigación que cumplen con los rangos físicos establecidos por la normativa INEN 1 429, como es el caso de los tratamientos: t7 (Fibra de Agave Sisalana, Carbonato de calcio, Dióxido de cloro) y t1 (Fibra de Agave Americana, Sulfato de sodio, Dióxido de cloro). Cumplen de esta manera con los indicadores y objetivos planteados, se realizó un balance de materiales utilizados en el proceso que demostró, que podemos optimizar recursos y volver a reutilizar el agua residual del proceso de humectación de la fibra.

Subsidence due to groundwater overexploitation has been recognized in the metropolitan area of Murcia (25 km²) in south-eastern Spain since the early 1990s. Previous published works have focused their attention on land subsidence that occurred during the drought period between 1995 and 2008. This work first analyzes the groundwater recovery that has occurred since 2008 and then determines the kind of associated ground deformation detected by the new extensometric data. Subsequently, subsidence time series are computed on 24 geotechnical boreholes scattered throughout the study area by means of a hydro-mechanical finite element code and a linear-elastic constitutive law. A spatio-temporal interpolation of the numerically modeled surface displacements is performed over the whole domain and compared with extensometers and DInSAR-derived displacement maps in two different periods: the drought period from 2004 to 2008, and the recovery period from 2008 to 2012. In spite of the limited information on the geomechanical parameters characterizing the modelled geological formations, the proposed approach is able to discriminate areas where the soils have an elastic behavior (small differences in the comparisons) or an elasto-plastic behavior (large differences in the comparisons). This zonation enhances the understanding of the subsidence phenomenon in Murcia City and could prevent, from a quantitatively point of view, future severe subsidence due to aquifer overexploitation.