Genetic diversity and species richness patterns in Baetidae (Ephemeroptera) in the Montseny Mountain range (North-East Iberian Peninsula)

This study aimed to describe patterns of diversity of Baetidae (Ephemeroptera) at the ommunity and population levels within the Montseny Mountain range (North-East Iberian Peninsula). We studied both the distribution of 4 species of baetids in 20 sites among three catchments along the altitudinal gradient (350-1700 masl); and the genetic diversity of the mtDNA cytochrome c oxidase subunit I (cox1) gene of the two common species Baetis alpinus and Baetis rhodani. We found a gradual replacement of the dominant species along the altitudinal gradient. Baetis alpinus inhabited sites at high-altitudes, and this species was replaced by B. rhodani when the altitude decreased. Baetis melanonyx and Alainites muticus attained low abundance at all river sections, and no clear altitudinal trend appeared. Our hypothesis at the population level was that genetic structuring is associated with geographic distance and limited by drainage boundaries among the three studied catchments because of the short-time dispersion of adults. Unexpectedly, analyses of molecular variance (AMOVA) and isolation-bydistance (IBD) showed genetic diversity was unstructured by distance for both species, which may be explained by the relatively short spatial scale studied and small topographic barriers among the three catchments. The Generalized Mixed Yule-Coalescent (GMYC) model showed that B. rhodani had two differentiated genetic lineages that co-occurred in all sites. Overall, diversity of baetids was structured at the community level along the altitudinal gradient, whereas it was unstructured at the population level within the Montseny Mountain range.

Imposicions estructurals en el drenatge de la conca del riu Onyar (Girona)

The Onyar River basin is situated in the depression of la Selva. His origins are related to tectonic activity during Neogen in this region. In his evolution, we note a slowly and continuous downfall which directs the morphodinamical behaviour. In this sense, the drainage network has a directional trend towards the north, as consecuence of fault systems, and specially the N-S oriented one. A fault of this system has an important influence in the basin morphology, directs the drainage towards the north and avoids a closely drainage in the basin

Evaluación de la reactividad de sulfuros de hierro y residuos mineros: una metodología basada en la aplicación de la voltamperometría cíclica

The mining industry around the world produces an important amount of wastes, which by their high toxic metal and iron sulfide content present a serious environmental problem. Iron sulfide oxidation under weathering conditions provokes the main environmental problem of the mining industry, the generation of Acid Rock Drainage (ARD). Up to now the prediction methodologies do not allow the study of important factors that influence the generation of ARD, producing in some cases erroneous or uncertain conclusions. This paper shows the utilization of cyclic voltammetry using carbon paste electrodes (CPE-Mineral) as an alternative tool in the study of the oxidation capacity of iron sulfides and mining wastes. This electrochemical technique constitutes a novel methodology to establish and understand the factors involved during generation of ARD. Results of several studies including selected sulfide samples and sulfide mining wastes have been described in order to show the capacity of this methodology as a complementary tool in the prediction of the generation of ARD.

Remediação de drenagem ácida de mina usando zeólitas sintetizadas a partir de cinzas leves de carvão

Zeolitic material was synthesized from coal fly ashes (baghouse filter fly ash and cyclone filter fly ash) by hydrothermal alkaline activation. The potential application of the zeolitic product for decontamination of waters from acid mine drainage was evaluated. The results showed that a dose of 30 g L-1 of zeolitic material allowed the water to reach acceptable quality levels after treatment. Both precipitation and cation-exchange processes accounted for the reduction in the pollutant concentration in the treated waters.

Fatores que governam a especiação do cobre em ambientes aquáticos urbanos: evidências da contribuição de sulfetos solúveis

Copper speciation and behavior in different rivers located in the city of Curitiba were evaluated in this work. Sampling locations were selected to cover different levels of urbanization regarding their anthropogenic occupation and land use. Results showed that in highly-developed areas, both organic matter and dissolved sulfides were able to control copper speciation. Dissolved sulfide species were the major complexing agent in areas where dissolved oxygen levels are low. Finally, it was demonstrated that in urban areas anthropogenic factors such as sewage inputs and occupation of the drainage basin are the key aspects controlling copper dynamics and speciation in river waters.

Proyecto de ejecución para las obras de concesión de dominio público para la reforma y adecuación de la central térmica y de la red de saneamiento en un hospital de 350 camas

El Hospital Punta de Europa en Algeciras (Cádiz), centro sanitario del Servicio Andaluz de Salud, desea optimizar la gestión de sus instalaciones de generación de energía térmica (vapor, agua caliente sanitaria y agua caliente de calefacción) y adecuarlas a la normativa vigente así como la sustitución de bajantes del edificio, para lo cual sacará a concurso público la licitación para la concesión de dominio público de dichas instalaciones. Para definir el alcance y condiciones de la citada concesión, el Hospital Punta de Europa (Algeciras) del Servicio Andaluz de Salud ha solicitado a Pedro Alonso Martín el estudio para la reforma y adecuación de las instalaciones productoras de energía térmica del citado Hospital. El objetivo principal de este trabajo es hacer un estudio, propuesta y valoración de las actuaciones necesarias para la reforma y mejora de la explotación de las instalaciones generadoras de energía térmica y de la red saneamiento interior del Hospital Punta de Europa de Algeciras (Cádiz). Las actuales instalaciones de generación térmica consumidoras de energía del hospital dentro del alcance de este Proyecto son: Generación de vapor (lavandería y esterilización). Producción de agua caliente sanitaria (ACS). Producción de agua caliente de calefacción. La mayoría de los equipos productores de energía datan del año 1975, por lo que en la mayoría de los casos se ha cumplido su plazo de amortización y periodo de vida útil. Se hace necesaria la instalación de gas natural, debido a que se tendrá que abastecer a todas las calderas de la central térmica. El diseño del sistema de producción de agua caliente sanitaria garantiza el máximo confort y economía del usuario, compatible con el máximo ahorro energético y la protección del medio ambiente, cubriendo las necesidades de agua caliente sanitaria mediante la combinación de un sistema de calderas a gas con los colectores solares.

Arsenic mobilization from sulfidic materials from gold mines in Minas Gerais State

Acid drainage results from exposition of sulfides to the atmosphere. Arsenopyrite is a sulfide that releases arsenic (As) to the environment when oxidized. This work evaluated the As mobility in six sulfidic geomaterials from gold mining areas in Minas Gerais State, Brazil. Grained samples (<2 mm) were periodically leached with distilled water, during 70 days. Results suggested As sorption onto (hydr)oxides formed by oxidation of arsenopyrite. Low pH accelerated the acid generation, dissolving Fe oxihydroxides and releasing As. Presence of carbonates decreased oxidation rates and As release. On the other hand, lime added to a partially oxidized sample increased As mobilization.

Processos físico-químicos em drenagem ácida de mina em mineração de carvão no sul do Brasil

Acid mine drainage generated from coal mine showed a pH of 3.2, high concentrations of SO4(2-), Al, Fe, Mn, Zn and minor As, Cd, Co, Cr, Cu, Ni and Pb. The major reduction in the concentration occurred for Al, As, Cr, Fe and Pb after the treatment with CaO. The evolution of these acid waters within the tributary stream showed decreasing concentration for all soluble constituents, except Al. This natural attenuation was controlled by pH (6.4 to 10.8) as a result of concurrent mixing with tributary stream and reaction with local bedrock that contains limestone. Aluminum increasing concentration during this evolution seems to be related to an input of Al-enriched waters due to the leaching of silicate minerals in alkaline conditions.

Parâmetros indicativos do processo de salinização em rios urbanos do semi-árido brasileiro

This study examined the spatial and temporal variations of six important parameters of the salt accumulation process in water samples collected along section urban of Contas River. The Na+, K+, Ca2+ and Mg2+ concentrations were determined by FAAS. The conductivity, total dissolved solids, Na+ and Ca2+ presented the largest seasonal and spatial variations in the urban area demonstrated that are appropriate indicators of urban contamination. The readily soluble salts in drainage urban, contribute for the degradation of the water of rivers located in semi-arid zones.

Rejeito de mineração de carvão como adsorvente para remoção da acidez, Fe (III), Al (III) e Mn (II) em drenagem ácida

This study aimed the use of coal mining waste as a new adsorbent for H3O+ and removal of Al (III), Fe (III) and Mn (II) from acid mine drainage. Data from kinetic and equilibrium of the adsorption of H3O+ followed the pseudo second-order and Langmuir isotherm models. The maximum adsorption capacity of H3O+ was 316 mmol kg-1. The adsorbent removed 100% of Al (III), 100% of Fe (III) and 89% of Mn (II), suggesting its use as an alternative for the treatment of acid mine drainage.

Transporte de glifosato pelo escoamento superficial e por lixiviação em um solo agrícola

Glyphosate was determined in runoff and leaching waters in agricultural soil that received an application of active ingredient and was exposed to simulated intensive rain conditions. The concentrations decreased during the simulation period and the concentrations of the runoff were higher than those achieved in the samples of leaching waters. The concentrations were lower than the pattern in the Brazilian Regulation MS N. 518/2004 for drinking water. The transported load of the applied active ingredient by the leaching was of 15.4% (w/w) and for the runoff was of 1.7% (w/w).

Ocorrência de agrotóxicos em águas subterrâneas de áreas adjacentes a lavouras de arroz irrigado

The objective this study was to monitor pesticide residues in groundwater at three different times and in seven regions producing rice in southern Brazil, in the 2007/08 season. Imazethapyr and fipronil were found in all regions studied. All groundwater samples from the Planície Costeira Interna to Lagoa dos Patos and Santa Catarina contained at least one pesticide. The lowest number of contaminated samples were detected in the Southern region. The highest frequency of contaminated samples was found after drainage of the rice fields. Only fipronil exceeded limits of potability, in 27% of samples, according European Community criteria.

Fontes e distribuição de matéria orgânica sedimentar no complexo estuarino-lagunar de Mundaú-Manguaba/AL, utilizando esterois e alcoóis como indicadores

The origin of the sedimentary organic matter in the Mundaú-Manguaba estuarine system was evaluated through the distribution and composition of sterols, alcohols and ancillary data. The muddy sediments of the lagoons are enriched in organic matter, derived from a mixture of autochthonous and allochthonous inputs. Mundaú exhibited moderate contamination by sewage, with coprostanol concentration as high as 4.4 µg g-1. The channels are characterized by sand and organic matter-poor sediments. The sediments from some rivers in the drainage basin accumulated organic matter derived only from terrestrial vegetation. Stanol/sterol ratios evidenced the preferential diagenesis of the autochthonous fraction of organic matter.

Measurement and Improvement of Wet Paper Web Strength

Various strength properties of paper are measured to tell how well it resists breaks in a paper machine or in printing presses. The most often measured properties are dry tensile strength and dry tear strength. However, in many situations where paper breaks, it is not dry. For example, in web breaks after the wet pressing the dry matter content can be around 45%. Thus, wet-web strength is often a more critical paper property than dry strength. Both wet and dry strength properties of the samples were measured with a L&W tensile tester. Originally this device was not designed for the measurement of the wet web tensile strength, thus a new procedure to handle the wet samples was developed. The method was tested with Pine Kraft (never dried). The effect of different strength additives on the wet-web and dry paper tensile strength was studied. The polymers used in this experiment were aqueous solution of a cationic polyamidoamine-epichlorohydrin resin (PAE), cationic hydrophilised polyisocyanate and cationic polyvinylamine (PVAm). From all three used chemicals only Cationic PAE considerably increased the wet web strength. However it was noticed that at constant solids content all chemicals decreased the wet web tensile strength. So, since all chemicals enhanced solid content it can be concluded that they work as drainage aids, not as wet web strength additives. From all chemicals only PVAm increased the dry strength and two other chemicals even decreased the strength. As chemicals were used in strong diluted forms and were injected into the pulp slurry, not on the surface of the papersheets, changes in samples densities did not happen. Also it has to be noted that all these chemicals are mainly used to improve the wet strength after the drying of the web.

Past, present and future - assessing changes in aquatic environments using subfossil diatoms

The deterioration of surface waters is one of the most important issues in the environmental management of the European Union. Thus, the EU Water Framework Directive 2000/60/EC (WFD) requires “good ecological and chemical status” of surface waters by 2015 allowing only a slight departure from ecological reference conditions characterized by the biological communities typical for the conditions of minimal anthropogenic impact. The WFD requires the determination of ecological reference conditions and the present ecological status of surface waters. To meet this legislative demand, sedimentary diatom assemblages were used in these studies with various methods 1) to assess natural and human activity induced environmental changes, 2) to characterize background conditions 3) to evaluate the present ecological status and 4) to predict the future of the water bodies in the light of palaeolimnological data. As the WFD refers to all surface waters, both coastal and inland sites were included. Two long and two short sediment cores from the Archipelago Sea in the northern Baltic Sea were examined for their siliceous microfossils in order to assess (1) the Holocene palaeoenvironmental history and (2) the recent eutrophication of the area. The diatom record was divided into local diatom assemblage zones (LDAZ, long cores) and diatom assemblage zones (DAZ, short cores). Locally weighted weighted averaging regression and calibration (LWWA) was applied for the quantitative reconstruction of past TN concentrations (short cores). An age model for the long cores was constructed by using independent palaeomagnetic and AMS-14C methods. The short cores were dated using radiometric (210Pb, 226Ra and 137Cs) methods. The long cores date back to the early history of the Archipelago Sea, which was freshwater – no salinity increase referable to the brackish phase of the Yoldia Sea is recognized. The nutrient status of the lacustrine phase was slightly higher in the Archipelago Sea than in the Baltic Proper. Initial brackish-water influence is observed at 8 150 ±80 cal. BP (LDAZ4), but fully brackish conditions were established at 7 700 ±80 cal. BP (LDAZ5). The diatom assemblages indicate increasing salinity, warming climate and possible eutrophic conditions during the lacustrine to brackish-water transition. The decreasing abundance of Pseudosolenia calcar-avis (Schultze) Sundström and the increasing abundance of the ice-cover indicator species Pauliella taeniata (Grunow) Round and Basson indicate decreasing salinity and climatic cooling after ca. 5 000 cal. BP. Signs of eutrophication are visible in the most recent diatom assemblage zones of both short cores. Diatom-inferred total nitrogen (DI-TN) reconstructions partially fail to trace the actual measured total nitrogen concentrations especially from the late 1980s to the mid 1990s. This is most likely due to the dominating diatom species Pauliella taeniata, Thalassiosira levanderi Van Goor and Fragilariopsis cylindrus (Grunow) W. Krieger being more influenced by factors such as the length of the ice-season rather than nutrient concentrations. It is concluded that the diatom assemblages of the study sites are principally governed by climate fluctuations, with a slight influence of eutrophication visible in the most recent sediments. There are indications that global warming, with reduced ice cover, could impact the spring blooming diatom species composition in the Archipelago Sea. In addition, increased sediment accumulation in the early 90s coincides with the short ice-seasons suggesting that warming climate with decreasing ice-cover may increase sedimentation in the study area. The diverse diatom assemblages dominated by benthic species (54 %) in DAZ1 in the Käldö Fjärd core can be taken as background diatom assemblages for the Archipelago Sea. Since then turbidity has increased and the diatom assemblages have been dominated by planktonic diatoms from around the mid 1800s onwards. The reconstructed reference conditions for the total nitrogen concentrations fluctuate around 400 μg l-1. Altogether two short sediment cores and eight short cores for top-bottom analysis were retrieved from Lake Orijärvi and Lake Määrjärvi to assess the impact of the acid mine drainage (AMD) derived metals from the Orijärvi mine tailings on the diatom communities of the lakes. The Cu (Pb, Zn) mine of Orijärvi (1757 – 1956) was the first one in Finland where flotation techniques (1911 – 1955) were used to enrich ore and large quantities of tailings were produced. The AMD derived metal impact to the lakes was found to be among the heaviest thus far recorded in Finland. Concentrations of Cu, Pb and Zn in Lake Orijärvi sediments are two to three orders of magnitude higher than background values. The metal inputs have affected Lake Orijärvi and Lake Määrjärvi diatom communities at the community levels through shifts in dominant taxa (both lakes) and at the individual level through alteration in frustule morphology (Lake Orijärvi). At present, lake water still has elevated heavy metal levels, indicating that the impact from the tailings area continues to affect both lakes. Lake Orijärvi diatom assemblages are completely dominated by benthic species and are lacking planktonic diatoms. In Lake Määrjärvi the proportion of benthic and tychoplanktonic diatoms has increased and the planktonic taxa have decreased in abundance. Achnanthidium minutissimum Kützing and Brachysira vitrea (Grun.) R. Ross in Hartley were the most tolerant species to increased metal concentrations. Planktonic diatoms are more sensitive to metal contamination than benthic taxa, especially species in the genus Cyclotella (Kützing) Brébisson. The ecological reference conditions assessed in this study for Lake Orijärvi and Lake Määrjärvi comprise diverse planktonic and benthic communitites typical of circumneutral oligotrophic lakes, where the planktonic diatoms belonging to genera Cyclotella , Aulacoseira Thwaites, Tabellaria Ehrenberg and Asterionella Hassall dominate in relative abundances up to ca. 70%. The benthic communities are more diverse than the planktonic consisting of diatoms belonging to the genera Achnanthes Bory, Fragilaria Lyngbye and Navicula St. Vincent. This study clearly demonstrates that palaeolimnological methods, especially diatom analysis, provide a powerful tool for the EU Water Frame Work Directive for defining reference conditions, natural variability and current status of surface waters. The top/bottom approach is a very useful tool in larger-scale studies needed for management purposes. This “before and after” type of sediment sampling method can provide a very time and cost effective assessment of ecological reference conditions of surface waters.