Abstract A homemade water purifying filter was prepared with simple materials and activated carbon, based on white quebracho charcoal, obtained by chemical activation with lemon juice and water. It showed efficiency in terms of filtering water contaminated with soil, seeds, leaves, etc. Secondary school students were also involved in reproducing the same design, achieving similar characteristics in terms of the filtration of contaminated water. His interest, concern, responsibility and dedication in solving the problem of water pollution through scientific knowledge and technological production with local and low-cost materials stands out. The adsorptive capacity of activated carbon was evaluated in the adsorption of 4.00 g of unsweetened coffee, adsorbate, varying the amount of carbon, adsorbent. A direct proportion relationship was obtained between the adsorbed amount of coffee and the amount of activated carbon used at room temperature and a colorimetric scale was observed with the decrease in the dark tone of the coffee. Finally, some physicochemical properties of activated carbon were obtained; which are, a density of 0.30 g/cm3, a specific heat of 0.308 cal/gºC and concentrations of humidity (5.67%), volatiles (26.87%), ashes (4.62%) and fixed carbon (62.84%).

Resumen Se preparó un filtro purificador de agua casero con materiales simples y con carbón activado, basado en carbón vegetal de quebracho blanco, obtenido mediante activación química con jugo de limón y agua. El mismo mostró eficiencia en cuanto a la filtración de agua contaminada con tierra, semillas, hojas, etc. También se hizo partícipe a estudiantes del nivel secundario en la reproducción del mismo diseño, alcanzando características semejantes en cuanto a la filtración de agua contaminada. Se destaca su interés, preocupación, responsabilidad y dedicación en la resolución de la problemática de contaminación en aguas a través del conocimiento científico y la producción tecnológica con materiales locales y de bajo costo. Se evaluó la capacidad adsortiva del carbón activado en la adsorción de 4,00 g de café sin azúcar, adsorbato, variando la cantidad de carbón, adsorbente. Se obtuvo una relación de proporción directa entre la cantidad adsorbida de café y la empleada de carbón activado a temperatura ambiente y se apreció una escala colorimétrica con la disminución en la tonalidad oscura del café. Finalmente, se obtuvieron algunas propiedades fisicoquímicas del carbón activado; las cuales son, una densidad de 0,30 g/cm3, un calor específico de 0,308 cal/gºC y concentraciones de humedad (5,67 %), volátiles (26,87 %), cenizas (4,62 %) y carbono fijo (62,84 %).

Resumen Introducción: El uso frecuente de plaguicidas es considerado actualmente una causa de contaminación ambiental debido a las altas tasas de ingreso de estas sustancias a los agroecosistemas. Esta situación es un riesgo para las especies que habitan en estos ecosistemas, en particular los anuros cuyas características los hacen propensos a la exposición e interacción con contaminantes ambientales. Objetivo: Informar la presencia de anormalidades en larvas del sapo común Rhinella arenarum que habitan en estanques rodeados por un agroecosistema. Métodos: En dos primaveras consecutivas (2015 y 2016), se monitorearon los eventos reproductivos del sapo común proveniente de sistemas de estanques temporales ubicados en zonas agrícolas y no agrícolas, cerca de la ciudad de La Plata (Buenos Aires, Argentina). Se midieron los parámetros fisicoquímicos de los estanques y se registraron las etapas de cada evento reproductivo como el número de sapos adultos, amplexos y nidadas. En el laboratorio, las larvas fueron medidas y fotografiadas, se registró su estado de desarrollo y se examinó la morfología de cada una bajo microscopio estereoscópico. Se procesaron muestras representativas (normales y anormales) de cada estanque estudiado para análisis histopatológico. Resultados: En la población de R. arenarum que vive dentro de un agroecosistema, se observó un menor número de adultos reproductores y puestas en relación con la del estanque en la zona no agrícola. Se recolectaron un total de 1 910 larvas: 529 y 1 381 larvas de estanques ubicados en zonas no agrícolas y agrícolas, respectivamente. Las larvas del agroecosistema mostraron dos tipos de anormalidades: severa flexión de la cola y distensión abdominal. Además, se pudo determinar cinco grados de gravedad en relación con la distensión abdominal. Conclusiones: Una alta frecuencia y severidad de anormalidades en los estadios tempranos de larvas de R. arenarum que viven dentro de un agroecosistema proporciona evidencia del impacto negativo que las actividades agrícolas causan en los ecosistemas acuáticos rodeados por áreas de cultivo.

Abstract Introduction: The frequent use of pesticides is currently considered a cause of environmental pollution due to the high rate of entry of these substances into agroecosystems. This constitutes a risk for the species that inhabit these ecosystems, in particular anurans whose characteristics make them prone to exposure to and interaction with environmental pollutants. Objective: To report the occurrence of abnormalities in larvae of the common toad Rhinella arenarum inhabiting ponds surrounded by agroecosystems. Methods: In two consecutive springs (2015 and 2016), reproductive events of common toads were monitored in temporary pond systems in agricultural and non-agricultural areas, located near the city of La Plata (Buenos Aires, Argentina). The physicochemical parameters of the ponds were measured, and the stage of each reproductive event was recorded, such as the numbers of adult toads, amplexus and clutches. In the laboratory, the larvae were measured and photographed, their stage of development was recorded, and their morphology was examined under a stereomicroscope. Representative samples (normal and abnormal) from each pond studied were processed for histopathological analysis. Results: In the field studies carried out on a population of R. arenarum collected in an agroecosystem, a lower number of reproductive adults and clutches were observed in relation to the population of a non-agricultural pond. A total of 1 910 larvae were collected: 529 and 1 381 larvae from ponds located in non-agricultural and agricultural areas, respectively. Larvae from the agroecosystem showed two types of abnormalities: severe tail flexure and abdominal bloating. In addition, five degrees of severity could be determined in relation to abdominal bloating. Conclusions: This work reports the high frequency and severity of abnormalities observed in the early stages of R. arenarum larvae living within an agroecosystem, providing evidence of the negative impact that agricultural activities cause on aquatic ecosystems surrounded by farming areas.

ABSTRACT The Morroa aquifer, which is an essential source of water supply in Sucre, Colombia, with more than 500,000 users, may be at risk because of pesticide contamination that comes from different agricultural activities. The aim of this research was to evaluate the relationship between the presence of pesticides and the physicochemical properties of soils in the most vulnerable areas of the Morroa aquifer. Therefore, farmers were surveyed about pesticide usage and soil samples which were taken for analysis of pesticide and physicochemical properties. The results demonstrated that soils in these areas were relatively homogeneous in terms of texture, pH, cation exchange capacity and organic matter content. Pesticides detected in these soils were malathion, β-BCH, p-p’DDE, m-p’DDD, p-p’DDT, endosulfan, endrincetone, chlorpyrifos, dieldrin, endosulfan-sulfate, heptachlor-epoxide, and parathion. Physicochemical properties such as pH and texture of soils and intrinsic characteristics of the pesticide were found as the most influential variables according to statistical results. This study also presents a map of the spatial distribution of pesticide concentration according to the concentration of pesticides, which constitutes an important tool for the planning of agricultural activities that supports decision-making and the implementation of measures to mitigate potential impacts caused by pesticide pollution.

RESUMO O aquífero de Morroa é uma fonte essencial para o abastecimento de água em Sucre, Colômbia, com mais de 500.000 usuários que podem estar em risco devido à contaminação por pesticidas que provêm de diferentes atividades agrícolas. O objetivo desta pesquisa foi avaliar a relação entre a presença de pesticidas e as propriedades físico-químicas dos solos nas áreas mais vulneráveis do Aquífero Morroa. Para isso foi aplicado um inquérito sobre a utilização de pesticidas aos agricultores e foram coletadas amostras de solo para análise de pesticidas e propriedades físico-químicas. Os resultados mostraram que os solos nestas áreas são relativamente homogéneos em termos de textura, pH, Capacidade de Troca Catiônica e Matéria Orgânica. Os pesticidas detectados nestes solos foram Malathion, β-BCH, p-p’DDE, m-p’DDD, p-p’DDT, Endosulfan, Endrincetone, Chlorpyrifos, Dieldrin, Endosulfan-Sulfate, Heptachlor-epóxido e Parathion. O pH, a textura do solo e as características intrínsecas do pesticida são as variáveis mais influentes de acordo com os resultados estatísticos. Este estudo também mostra a distribuição espacial da concentração de pesticidas em toda a área do aquífero. O mapa elaborado constitui uma ferramenta para o planeamento de atividades agrícolas que subsidia a tomada de decisões e a implementação de medidas para mitigar os potenciais impactos causados pela poluição causada pelos pesticidas.

Abstract In this paper, a couple of pretreatments were applied to raw cheese whey to increase its biodegradability in an anaerobic reactor. The first stage consisted of coagulation/flocculation using Carica papaya seeds as a biocoagulant, and the second stage was a study of Fenton and photo-Fenton processes. The cheese whey was collected from a dairy industry plant and characterized according to physicochemical parameters to check the pollution potential (chemical oxygen demand — COD of 55.96 g L−1 and biochemical oxygen demand — BOD of 21.51 g L−1). The coagulation/flocculation process provided high turbidity removal (94–96%). After preliminary experiments with Fenton reactions in coagulated whey, a central composite design, a desirability function and a response surface were applied to obtain the optimal operating conditions (reaction time: 90 min, H2O2: 1.95 M; H2O2/Fe2+ ratio: 55) resulting in 66.4 and 62.6% of COD and TOC removals, respectively. The kinetic evaluation of photo-Fenton reaction under optimal conditions revealed the potential minimization of iron (H2O2/Fe2+ ratio: 65) and reaction time (60 min) to achieve 70.1% of COD removal under visible ultraviolet light irradiation (UV/vis). After applying the coagulation/flocculation and photo-Fenton processes, an increase in biodegradability was achieved (BOD5/COD > 0.4), allowing the application of the biological process. The batch treatment in a UASB reactor achieved 86–88% COD removal from the 24th day of operation. The proposed hybrid process eliminated between 96–98% of total COD.

Resumo Neste artigo, dois pré-tratamentos foram aplicados ao soro de queijo bruto para aumentar sua biodegradabilidade na aplicação de um reator anaeróbio. A primeira etapa consistiu na coagulação/floculação utilizando sementes de Carica papaya como biocoagulante, e a segunda etapa foi o estudo dos processos Fenton e foto-Fenton. O soro foi coletado em uma fábrica de laticínios e caracterizado quanto a parâmetros físico-químicos para verificar o potencial poluidor (demanda química de oxigênio — DQO 55,96 g L−1 e demanda bioquímica de oxigênio — DBO de 21,51 g L−1). O processo de coagulação/floculação promoveu a remoção de nível alto de turbidez (94–96%). Após testes preliminares das reações Fenton no soro coagulado, houve a aplicação do delineamento de composto central, da função desejabilidade e da superfície de resposta para obter as condições ótimas de operação (tempo reacional: 90 min, H2O2: 1,95 M e razão H2O2/Fe2+: 55), resultando em 66,4 e 62,6% de remoção de DQO e TOC, respectivamente. A avaliação cinética da reação foto-Fenton nas condições otimizadas revelou o potencial da minimização da concentração de ferro (razão H2O2/Fe2+: 65) e do tempo reacional (60 min) para atingir 70,1% de remoção de DQO sob irradiação de luz ultravioleta visível (UV-vis). Após aplicação dos processos de coagulação/floculação e foto-Fenton, um aumento da biodegradabilidade foi alcançado (DBO5/DQO > 0,4), possibilitando a aplicação do processo biológico. O tratamento batelada em reator anaeróbio de manta de lodo de fluxo ascendente (UASB) promoveu 86–88% de remoção de DQO a partir do 24º dia de operação. O processo de tratamento híbrido proposto eliminou entre 96 e 98% da DQO total.

Abstract Aim This study aimed to evaluate the interference of intensive fish farming in the physicochemical variables of water and in the zooplankton community from a tilapia (Oreochromis niloticus Linnaeus, 1758) pond in southern Brazil. In addition, it was verified whether the analyzed zooplankton groups could be bioindicators of changes in the quality of pond water. Methods The water and zooplankton sample collections were carried out monthly in different places of the pond: at the water supply site (affluent), in the middle of the pond and at the water outlet site (effluent). Analyzes related to nitrogen series (total nitrogen, total ammonia, nitrite + nitrate), dissolved oxygen, total hardness, total alkalinity, total phosphorus, pH, turbidity and water temperature were performed at all sampling sites. In addition, the density of the zooplankton groups Copepoda (adults and nauplii), Rotifera and Cladocera was determined. Results Regarding the changes between the quality variables of the affluent and effluent water of the pond, the outlet water showed a significant increase only in the variable total alkalinity. Rotifers were the most abundant organisms, and nauplii Copepoda showed a significant increase in the density of organisms in the middle of the pond compared to the inlet water. Both the redundancy analysis (RDA) and the Spearman correlation matrix revealed that zooplanktonic groups are associated with certain physicochemical variables of the water. According to the Analysis of Indicator Species (IndVal), the evaluated organisms are not related to bioindicator species in this environment. Conclusions Therefore, intensive production of O. niloticus caused changes only in the total alkalinity of the pond water. The zooplanktonic organisms correlated with the physicochemical variables of the water and between the groups, and did not show potential for bioindicators of water quality in the different locations of the pond.

Resumo Objetivo Este estudo teve como objetivo avaliar a interferência da piscicultura intensiva nas variáveis físico-químicas da água e na comunidade zooplanctônica de um viveiro de tilápias (Oreochromis niloticus Linnaeus, 1758) no sul do Brasil. Além disso, verificou-se se os grupos de zooplâncton analisados poderiam ser bioindicadores de alterações na qualidade da água do viveiro. Métodos As coletas de amostras de água e zooplâncton foram realizadas mensalmente em diferentes locais do viveiro: no local de abastecimento de água (afluente), no meio do viveiro e no local de saída de água (efluente). Foram realizadas análises relacionadas a série nitrogenada (nitrogênio total, amônia total, nitrito + nitrato), oxigênio dissolvido, dureza total, alcalinidade total, fósforo total, pH, turbidez e temperatura da água em todos os locais de amostragem. Além disso, foi determinada a densidade dos grupos de zooplânctons Copepoda (adultos e náuplios), Rotifera e Cladocera. Resultados Em relação às variações entre as variáveis de qualidade da água afluente e efluente do viveiro, a água de saída apresentou aumento significativo apenas na variável alcalinidade total. Os rotíferos foram os organismos mais abundantes, e os Copepoda náuplios apresentaram um aumento significativo na densidade de organismos no meio do viveiro em comparação com a água de entrada. Tanto a análise de redundância (RDA) quanto a matriz de correlação de Spearman revelaram que grupos zooplanctônicos estão associados a determinadas variáveis físico-químicas da água. De acordo com a Análise de Espécies Indicadoras (IndVal), os organismos avaliados não apresentam relação como espécies bioindicadoras deste ambiente. Conclusões A produção intensiva de O. niloticus causou alterações apenas na alcalinidade total da água do viveiro. Os organismos zooplanctônicos apresentaram correlação com as variáveis físico-químicas da água e entre os grupos, e não apresentaram potencial para bioindicadores da qualidade da água nos diferentes locais do viveiro.

Abstract Aim The present study investigated the influence of environmental variables on macrobenthic fauna in the Achenkovil River, Southern Western Ghats, Kerala. The knowledge of aquatic ecosystems in many remote areas is very scanty and no one has yet made an attempt to study the macrobenthic fauna of Achenkovil river. Since, macrobenthos play an important role in the benthic community structure a better knowledge of their ecology and distributional patterns in remote freshwater ecosystems would be of great interest for a better understanding of their functioning. Methods A bimonthly sampling was conducted from February 2019 to January 2020. Water samples for physicochemical analysis were carried to the laboratory in clean polyethylene bottles. The macrobenthic fauna was collected using Van Veen grab (0.025m2). Multivariate statistical technique such as Principal Component Analysis was used to monitor the variation in environmental parameters. The diversity of macrobenthic fauna was studied using Simpson_1-D, Shannon_H, Evenness_e^H/S, and Margalef’s indices. We analyzed the relationship between environmental variables and macrobenthic fauna, using Canonical Correlation Analysis and Pearson correlation. Results A total of 3563 individuals belonging to 9 orders, 32 families, 32 genera, and 32 species were identified. The most dominant order was Ephemeroptera followed by Coleoptera and Trichoptera and the least dominant was Zygoptera. The maximum number of macrobenthic fauna was observed in station 1(S1), (1461 Ind/m2) and the least in station 9 (S9), (37 Ind/m2). Station 1 (S1) is a pristine forest area, so this area is considered the reference site. The macrobenthic fauna in the pristine headwater forests (S1) was much more diverse than in the river mouth (S9) which is a highly impacted region. This region is facing various kinds of anthropogenic stress resulting in pollution and deterioration of water quality. The macrobenthic community structure in the Achenkovil River was significantly associated to the variations in water quality due to various natural as well as anthropogenic stresses. Conclusions It can be concluded that Ephemeroptera, Coleoptera, and Trichoptera were the most dominant groups in the undisturbed habitats in the river during the study period. The predominance of Chironomidae species, especially from the Chironomus genus in the midstream and downstream segments of the river is possibly due to their ability to adapt to various environmental conditions or habitats and their tolerance to the low oxygen content in anoxic conditions of the bottom sediment. The lowest abundance of macrobenthos at all the studied stations was observed at station 9 (S9) during dry seasons. S9 is a highly impacted region, characterized by high temperature, turbidity, TDS, pH, conductivity, nitrate, and phosphate values. For this reason, anthropogenic stress and changing environmental conditions are the main factors affecting the distribution of the macrobenthic fauna of the Achenkovil River basin, Kerala.

Resumo Objetivo O presente estudo investigou a influência de variáveis ambientais na fauna macrobêntica no rio Achenkovil, Southern Western Ghats, Kerala. O conhecimento dos ecossistemas aquáticos em muitas áreas remotas é muito escasso e ninguém ainda fez uma tentativa de estudar a fauna macrobentônica do rio Achenkovil. Uma vez que os macrobenthos desempenham um papel importante na estrutura da comunidade bentônica, um melhor conhecimento de sua ecologia e padrões de distribuição em ecossistemas remotos de água doce seria de grande interesse para uma melhor compreensão de seu funcionamento. Métodos Foram realizadas coletas bimensais de fevereiro de 2019 a janeiro de 2020. As amostras de água para análises físico-químicas foram levadas ao laboratório em frascos de polietileno limpos. A fauna macrobentônica foi coletada usando garrafa de Van Veen (0,025m2). A técnica estatística multivariada, como a Análise de Componentes Principais, foi utilizada para monitorar a variação dos parâmetros ambientais. A diversidade da fauna macrobêntica foi estudada usando os índices Simpson_1-D, Shannon_H, Evenness_e^H/S e Margalef. Analisou-se a relação entre as variáveis ambientais e a fauna macrobêntica, utilizando a Análise de Correlação Canônica e a Correlação de Pearson. Resultados Foram identificados 3.563 indivíduos pertencentes a 9 ordens, 32 famílias, 32 gêneros e 32 espécies. A ordem mais dominante foi Ephemeroptera seguida por Coleoptera e Trichoptera e a menos dominante foi Zygoptera. O número máximo de fauna macrobentônica foi observado na estação 1(S1), (1461 Ind/m2) e o menor na estação 9 (S9), (37 Ind/m2). A Estação 1 (S1) é uma área de floresta intocada, portanto esta área é considerada o local de referência. A fauna macrobentônica nas florestas virgens da cabeceira (S1) foi muito mais diversa do que na foz do rio (S9), que é uma região altamente impactada. Esta região enfrenta vários tipos de estresse antropogênico, resultando em poluição e deterioração da qualidade da água. A estrutura da comunidade macrobentônica no rio Achenkovil foi significativamente associada às variações na qualidade da água devido a vários estresses naturais e antrópicos Conclusões Pode-se concluir que Ephemeroptera, Coleoptera e Trichoptera foram os grupos mais dominantes nos habitats não perturbados no rio durante o período de estudo. A predominância de espécies de Chironomidae, principalmente do gênero Chironomus nos segmentos médio e jusante do rio, possivelmente se deve à sua capacidade de adaptação a diversas condições ambientais ou habitats e sua tolerância ao baixo teor de oxigênio em condições anóxicas do sedimento de fundo. A menor abundância de macrobentos em todas as estações estudadas foi observada na estação 9 (S9) durante as estações secas. S9 é uma região altamente impactada, caracterizada por alta temperatura, turbidez, TDS, pH, condutividade, nitratos e valores de fosfato. Por esta razão, o estresse antropogênico e a mudança das condições ambientais são os principais fatores que afetam a distribuição da fauna macrobentônica da bacia do rio Achenkovil, Kerala.

Resumen: La productividad agrícola de la Amazonía Ecuatoriana es deficiente debido a la mala calidad del suelo, ocasionada por diversos contaminantes. El objetivo del presente estudio fue identificar el potencial agrícola de suelos de la Amazonía Ecuatoriana, a partir de variables físico-químicas, biológicas y ambientales. Para esto, se tomaron 10 muestras de suelo de los principales agroecosistemas. Las variables físico-químicas se determinaron mediante técnicas estandarizadas. Para el conteo de bacterias (UFC/gr) se usó la metodología de recuento en placa y para la descripción ambiental se usaron variables espaciales (distancia a centros poblados) y espectrales (índice de vegetación de diferencia normalizada NDVI, infrarrojo cercano NIR, índice de vegetación mejorado EVI). A partir del pH, carbono orgánico y saturación relativa (Bases y Al+H) se definieron índices de fertilidad potencial (IFP). Se presentó un pH ácido en todos los suelos y un porcentaje de materia orgánica menor al 2%, con un nivel promedio de Al y Al+H de 3.7 y 5.7 mEq 100 mL-1. Las relaciones de Ca Mg-1, Mg K-1 y (Ca+Mg) K-1 fueron de 7.7, 10.2 y 83.4. Se observó una relación significativa directa entre el pH y el Ca y Mg, con coeficientes de correlación de 0.67 y 0.80. El promedio IFP de los suelos fue 0.46, con rango de 0.33-0.65. La concentración de Cd y Pb fue 0.13 y 59.35 mg kg-1. El conteo de bacterias presentó valores altos en dos muestras (2.64×108 y 2.13×108). El 70% de las áreas se corresponden con el uso de suelo tierra agropecuaria-pastizal. La menor variación se observó en el NDVI, que tuvo un promedio de 0.77. El área central de la zona de muestreo tuvo altos niveles de contaminantes (Al, Cd, Pb), así como la zona de influencia alrededor de estos puntos. Es necesario implementar estrategias de remediación, para favorecer las prácticas agrícolas.

Summary: Agricultural productivity in the Ecuadorian Amazon is deficient due to poor soil quality caused by various pollutants. The aim of this study was to identify the agricultural potential of soils in the region of the Ecuadorian Amazon, from variable physicochemical, biological and environmental. The soil samples were taken major agroecosystems. The physicochemical variables were determined by standard techniques. Bacteria (CFU/gr) were determined by counting methodology used in plate. Environmental variables spatial (distance to populated centers) and spectral (normalized difference vegetation index NDVI, near infrared NIR, enhanced vegetation index EVI) variables were used for environmental description. From pH, organic carbon and relative saturation (Bases and A+H) the potential fertility indexes (IFP) were defined. An acid pH was presented in all the soils and percentage of organic matter was lower to 2%. with an average level of A and A+H of 3.7 and 5.7 mEq 100 mL-1. Relations of Ca Mg-1, Mg K-1 and (Ca + Mg) K-1 were 7.7, 10.2 and 83.4. Significant direct relationship between pH and Ca and Mg, with correlation coefficients of 0.67 and 0.80 were observed. IFP average of soil was 0.46, ranging from 0.33 to 0.65. The concentration of Cd and Pb was 0.13 and 59.35 mg kg-1. The bacteria count showed no difference; however, two soils showed the highest values (2.64×108 and 2.13×108 UFC). 70% of areas were in agricultural-pasture land use. The lowest variation was observed in the normalized difference vegetation index which had an average of 0.77. The central area of the sampling area had high levels of pollutants (Al, Cd, Pb) and the zone of influence around these points. It is necessary to implement remediation strategies in the sampling area, to promote agricultural practices.

Resumo A crescente poluigao de ambientes marinhos e estuarinos por descarga de efluentes é um problema mundial. Os ensaios ecotoxicológicos vem sendo amplamente utilizados para monitorar os efeitos deste tipo de poluigao e, atualmente sao incorporados na legislagao ambiental de diversos países, nomeadamente no Brasil. Contudo, sao poucos os estudos realizados em áreas costeiras e a padronizagao de métodos com organismos nativos, representativos de ecossistemas locais, é insuficiente. Nitocra sp. tem sido eficientemente utilizado em ensaios ecotoxicológicos com sedimentos e águas intersticiais, sendo neces-sário avaliar a sua adequagao na análise de águas superficiais estuarinas. Amostras pontuais de agua do baixo estuário Jundiaí -Potengi (EJP) foram coletadas mensalmente durante 18 meses, em áreas com (CE) e sem (SE) recegao de efluentes tratados. Nitocra sp. e Mysidopsis juniae (espécie padronizada) foram os organismos teste utilizados nos ensaios ecotoxicológicos. Efeitos letais (taxa de mortalidade) e subletais (taxa de reprodugao) foram analisados considerando a caracterizagao microbiológica e físico-química das amostras testadas. Os teores de oxigenio dissolvido, salinidade, demanda bioquímica de oxigenio, nitrogenio amoniacal e amoniacal total, nitrogenio total, óleos e graxas, sólidos suspensos e sedimentáveis, potássio total e coliformes termotolerantes determinados nas amostras CE e SE, traduzem diferentes níveis de poluigao nos locais amostrados. As cartas-controle de Nitocra sp. e M. juniae indicaram boa reprodutibilidade laboratorial, e apesar dos organismos teste terem exibido diferentes perfis ecotoxicológicos, o aumento da taxa de mortalidade de ambos esteve associada a emissao de esgoto tratado. O uso de diferentes organismos teste favorece a representatividade dos ensaios ecotoxicológicos. Considerando o perfil de Nitocra sp. no monitoramento do EJP, o seu estabelecimento como organismo-teste padronizado necessita de mais estudos, incluindo a utilizagao de nauplii em bioensaios.

Abstract Increasing pollution of marine and estuarine environments from wastewater discharge is a worldwide problem. Eco-toxicological tests are widely used to monitor the effects of this type of pollution and are currently being incorporated into the environmental legislation of several countries, including Brazil. However, few studies have been conducted in coastal areas, and standardization of methods with native organisms representative of local ecosystems is insufficient. Nitocra sp. has been efficiently used in ecotoxicological tests with sediments and interstitial waters, and its suitability for estuarine surface water analysis needs to be assessed. Point samples from the lower Jundiaí-Potengi estuary (JPE) in areas with (CE) and without (SE) discharge of treated effluents were collected monthly for 18 months. Nitocra sp. and Mysidopsis juniae (standardized species) were the test organisms used in the ecotoxicological assays. The lethal (mortality rate) and sublethal (reproduction rate) effects were analyzed considering the microbiological and physicochemical characterization of the tested samples. Dissolved oxygen, salinity, biochemical oxygen demand, ammoniacal and total ammoniacal nitrogen, total nitrogen, oils and greases, suspended and settleable solids, total potas-sium and thermotolerant coliform bacteria determined in samples from CE and SE, reflect varying levels of pollution at the sampled sites. The control charts of Nitoera sp. and M. juniae indicated good reproducibility in the laboratory, and although the test organisms had different ecotoxicological profiles, the mortality rate of both organisms was related to the discharge of treated wastewater. The use of different test organisms increases the representativeness of the ecotoxicological tests. Given the profile of Nitoera sp. in JPE monitoring, further studies, including the use of nauplii in bioassays, are needed to establish it as standardized test organism.

ABSTRACT In Chile, metal mining is concentrated between the Administrative Regions IV and VI (which includes the Metropolitan Region). The northern and central zones of the country have abundant copper as well as mineral iodine and iron. Today, these residues are stored in tailing dams. Mine tailings constitute the toxic residues composed of trace elements, which in many occasions are deposited in areas neighboring human settlements and are a health hazard for the inhabitants In this work, the concentrations of trace elements such as: Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Zn were studied in 6 sites of the tailings located within Andacollo city, Northern Chile. The sampling points were recorded using GPS geographic coordinates and, in the laboratory, they were characterized determining: pH, electrical conductivity, soluble organic carbon, total organic carbon, available phosphorus, boron, total nitrogen and capacity cation exchange. The concentrations of trace elements in tailings samples, were quantified by atomic absorption spectrophotometry (AAS). Potential anthropogenic hotspots were assessed using indices including enrichment factor (EF), geoaccumulation index (Igeo), contamination factor (CF), Pollution load index, (PLI), ecological risk (Ei) and potential ecological risk (PERI) index. These indexes are used to assess the presence and intensity of anthropogenic contaminant deposition on surface soil. The physicochemical characterization of the tailings allowed establishing a profile of the environmental conditions of the sampled sites. The sites that presented a higher concentration of metals correspond to sites 4 and 6. The polluted index values than indicated, high degree of contamination for Cu, Hg and Mo by other hand PLI and Ri index indicated the sites more polluted are 4,5 and 6.

Excessive discharge of poorly treated effluent has impacted global water resource systems intensely. The declining state of wastewater treatment plants (WWTPs) is a significant source of pollution in water resources. There is evidence of water resource quality deterioration in natural environments caused by effluent discharges. We assessed the impact of wastewater treatment effluent on the quality of the Crocodile River. For spatial distribution, we collected data from three WWTPs discharging effluent into the Crocodile River and from three points situated downstream of each WWTP. Physicochemical and microbiological parameters such as pH, electrical conductivity, chemical oxygen demand, phosphates, nitrates, ammonia, and Escherichia coli were analysed using standard methods of the American Public Health Association. The water quality index was also calculated to give an overall indication of pollution within the catchment. The results show that WWTPs were not complying with the effluent standards set out in their water use licence. The WWTP effluent had a negative impact on downstream water quality, with the water quality index indicating low quality of discharged effluent. It is recommended that a regular and consistent water resource quality monitoring programme be implemented, particularly in areas where effluent discharges are prevalent. SIGNIFICANCE: In many African nations, water pollution is a serious problem that may be traced to a variety of sources. Surface water pollution has adverse effects on aquatic ecosystems and reduces the availability of clean water. In most semi-arid to dry southern African regions (e.g. South Africa), water scarcity is a significant concern. In these regions, water is a vital resource that must be protected at all times, given that the inadequate infrastructure of wastewater treatment facilities adds to the decline in South Africa's water quality standards.

RESUMO O lançamento irregular de esgoto doméstico e resíduos sólidos no sistema de drenagem, resultando na poluição dos corpos hídricos urbanos, é uma realidade comumente encontrada em todo o Brasil. Este estudo analisa a aplicação de medidas de desenvolvimento de baixo impacto na área de drenagem do Riacho das Piabas, localizado em Campina Grande – Paraíba, por meio da modelagem hidrológica dos indicadores de poluição das águas, utilizando o programa Storm Water Management Model. Monitorou-se indicadores físico-químicos de qualidade de água, em períodos seco e chuvoso, e mediu-se vazões ao longo do canal e contribuições do esgoto. Na etapa de modelagem, simulou-se três cenários: a) atual em período seco; b) atual em período chuvoso; c) cenário prevendo a aplicação de medidas estruturais e não estruturais de desenvolvimento de baixo impacto. No cenário atual em período seco, verificou-se que o processo de propagação de fluxo do escoamento eleva as concentrações dos indicadores ao longo do canal. Na simulação do período chuvoso, ocorreu diluição das concentrações dos indicadores em eventos com grande volume precipitado. Por fim, a simulação do último cenário mostrou que a adoção das medidas de desenvolvimento de baixo impacto resulta na redução das cargas poluentes do escoamento superficial e na melhoria da qualidade das águas do canal.

ABSTRACT The irregular release of domestic sewage and solid waste into the drainage system, resulting in the pollution of urban water bodies, is a reality commonly found throughout Brazil. This study analyzes the application of Low Impact Development measures in the drainage area of Riacho das Piabas, in the city of Campina Grande, state of Paraíba, through the qualitative hydrological modeling of water pollution indicators, using the Storm Water Management Model program. Physicochemical indicators of water quality were monitored, in both dry and rainy periods, and flow measurements along the channel and sewage contributions were made. In the modeling stage, three scenarios were simulated: a) current in the dry period; b) current in the rainy season; c) a scenario foreseeing the application of structural and non-structural Low Impact Development measures. In the current dry season scenario, it was found that the flow propagation process increases the concentrations of the indicators along the channel. In the simulation of the rainy season, it was observed that there is a dilution of concentrations of the indicators in events with large, precipitated volume. Lastly, the simulation of the third scenario showed that the adoption of Low Impact Development measures leads to the reduction of polluting loads from surface runoff and to the improvement of quality of channel water.

Resumen (Introducción): La biorremediación es una tecnología que utiliza microorganismos (bacterias, hongos, algas) o enzimas, para biodegradar contaminantes del petróleo y derivados y como otros contaminantes que están presentes en suelo, aire o agua. En América Latina, existe un alto grado de contaminación de sus ecosistemas; por tanto, esta tecnología es viable económica y ambientalmente para degradar contaminantes. Los hidrocarburos aromáticos policíclicos como asfaltenos y resinas son difíciles de degradar, así como los alifáticos y bifenilos policlorados. (Objetivo): Se busca dar una visión general de las publicaciones recientes sobre investigaciones científicas realizadas y metodologías de biorremediación de suelos contaminados por petróleo y sus derivados. (Metodología): Se realizó una búsqueda exhaustiva de la literatura científica de los últimos años, relacionada con el tema propuesto en bases de datos bibliográficas: Medline, Current Contents, PubMed, Google scholar, SciFinder, Scopus y en revistas especializadas: Chemosphere, Microbiología Aplicada, Biodegradation & Biodeterior, Sociedad Americana de Microbiología, Microbiología Frontal, Sci Total Environ. Las palabras clave utilizadas fueron en español o inglés. (Resultados): Los hidrocarburos poliaromáticos pueden ser biodegradados por diferentes bacterias que biodegradan solas o en consorcio, como el fenantreno (compuesto aromático) que fue biodegradado por 11 cepas bacterianas diferentes ( Sphingobium, Sphingomonas, Acidovorax, Alkaligenes, Actinobacteria, Burkholderia sp., Rhizobium sp., Pseudomonas sp., Stenotrophomonas y Sinorhizobium ). En biorremediación, se considera importante las variables fisicoquímicas, como el pH, temperatura, oxígeno y la humedad, al ser factores que influyen en el éxito del tratamiento. (Conclusiones): Se buscó aportar con esta revisión, soluciones viables a variados problemas de contaminación por hidrocarburos de los ecosistemas latinoamericanos.

Abstract (Introduction): Bioremediation is a technology that uses microorganisms (bacteria, fungi, algae) or enzymes to biodegrade oil pollutants and derivatives and other pollutants that are present in soil, air, or water. In Latin America there is a high degree of pollution of its ecosystems, therefore, this technology is economically and environmentally viable to degrade these pollutants. Polycyclic aromatic hydrocarbons, such as asphaltenes and resins, are difficult to degrade, as well as polychlorinated aliphatics and biphenyls. (Objective): It seeks to give an overview of recent publications on scientific research carried out regarding bioremediation methodologies for soils contaminated by oil and its derivatives. (Methodology): An exhaustive search of the scientific literature of recent years was carried out, related to the proposed topic in bibliographic databases: Medline, Current Contents, PubMed, Google scholar, SciFinder, Scopus and in specialized journals: Chemosphere, Applied Microbiology, Biodegradation & Biodeterior, American Society for Microbiology, Frontal Microbiology, Sci Total Environ. The keywords used were in Spanish or English. (Results): Polyaromatic hydrocarbons can be biodegraded by bacterial consortia, such as phenanthrene (aromatic compound) which was biodegraded by 11 different bacterial strains (Sphingobium, Sphingomonas, Acidovorax, Alkaligenes, Actinobacteria, Burkholderia sp., Rhizobium sp., Pseudomonas sp., Pseudomonas sp., Stenotrophomonas and Sinorhizobium). In bioremediation, physicochemical variables such as pH, temperature, oxygen, and humidity are considered important, as they are factors that influence the success of the treatment. (Conclusions): With this bibliographic review, we seek to provide viable solutions to various hydrocarbon pollution problems in Latin American ecosystems.

Resumen La cuenca del río Ayuquila-Armería se encuentra dentro de la clasificación de cuencas prioritarias de México, dada su alta diversidad, alto grado de alteración de la dinámica funcional y los niveles de presión social que presenta, por ende, es necesario realizar un análisis de la calidad del agua dentro de la cuenca. El objetivo fue evaluar la contaminación orgánica, realizando dos periodos de muestreo en temporada de lluvia (2015), y seca (2016), en 18 sitios de la cuenca. Se implementó el análisis integral de variables físicoquímicas y biológicas. El 90 % de los sitios presento eutrofización dadas las concentraciones de PTotal; el 77 % superó el límite permisible para las concentraciones de NTotal; el IIB evidencio que el 19 % de los sitios presenta un alto grado de contaminación orgánica; en la temporada lluviosa se encontraron las mayores concentraciones de UFC (18 a 190 UFC/mL) y un 50 % de los sitios superó el límite permisible (10 UFC/mL). La influencia de los afluentes tributarios al cauce principal aumenta drásticamente en la temporada de lluvias, se incrementa los caudales y empobrece la calidad del agua superficial por el arrastre de contaminantes desde las zonas rurales y urbanas.

Abstract The Ayuquila-Armería river basin is within the priority basins classification in Mexico, given its high diversity, and due to its high degree of functional dynamics alteration and levels of social pressure it presents; therefore, it is necessary to carry out an analysis of water quality within the basin. The objective was to evaluate organic contamination, carrying sampling campaigns in two seasons, one in the rainy (2015) and the other in the dry (2016) season, at 18 sites in the basin, through the implementation of a comprehensive analysis of physicochemical and biological variables. According to PTotal concentrations, 90% of the sites presented eutrophication, exceeding 77% of them the permissible limit for NTotal concentrations. The IIB showed that 19% of the sites present a high degree of organic contamination, with highest CFU concentrations (18 to 190 CFU / mL) found in the rainy season and 50% of the sites exceeding the permissible limit (10 CFU / mL). The influence of tributary influents to the main channel increases drastically in the rainy season, increasing flows and impoverishes the surface water quality by pollutants carryover from rural and urban areas.

Abstract The Peruvian mining sector is of great importance to rural populations due to the economic benefits it generates; however, it can also produce negative effects on water resources. The main of this study is to address a multidisciplinary approach to the study of the mining influence in the Ollachea Community and the Mining Community through the physicochemical evaluation of the Osccocachi River, the social perception of water quality and the comparative analysis of territorial expansion. mining and population. The results reveal that there is a level of mild acidity with a pH of 5.9 in the final stretch of the river that could affect the surrounding population, who stated that the prevalence of gastrointestinal diseases is mainly caused by the development of mining in the area. Multi-temporal satellite images from 2010 to 2019 revealed that the growth of the Ollachea Community is strongly associated with the territorial expansion of the Ollachea Mining Community (r=0.95, p<0.05). Finally, it is concluded that the territorial expansion and the physicochemical characteristics of the river coincide with the population's perception of the quality of the water, revealing that there is an environmental alteration generated mainly by mining activity.

Resumen El sector minero peruano tiene una gran importancia para las poblaciones rurales por los beneficios económicos que genera; sin embargo, también puede producir efectos negativos en los recursos hídricos. El objetivo de este estudio es abordar un enfoque multidisciplinario para el estudio de la influencia minera en la Comunidad de Ollachea y la Comunidad Minera mediante la evaluación fisicoquímica del río Osccocachi, la percepción social de la calidad del agua y el análisis comparativo de la expansión territorial minera y poblacional. Los resultados revelan que existe un nivel de acidez leve con un pH de 5.9 en el tramo final del río que podría afectar a la población aledaña, quienes manifestaron que la prevalencia de enfermedades gastrointestinales es causada principalmente por el desarrollo de la minería en la zona. Las imágenes satelitales multitemporales desde el año 2010 al 2019, revelaron que el crecimiento de la Comunidad de Ollachea está fuertemente asociado a la expansión territorial de la Comunidad Minera de Ollachea (r=0.95, p<0.05). Finalmente, se concluye que la expansión territorial y las características fisicoquímicas del río coinciden con la percepción de la población sobre la calidad del agua, revelando que existe una alteración ambiental generada principalmente por la actividad minera.

ABSTRACT Páramos are unique strategic ecosystems in the neotropical region, above the upper limit of closed forest and below the lower limit of perpetual snow in the tropical mountains of Central and South America. Their soils are of particular importance for water regulation and carbon storage; however, thousands of peasants develop agricultural activities such as potato cultivation and livestock farming in these areas. This research aimed to evaluate the possible heavy metals contents (arsenic, cadmium, mercury, and lead) and pesticide residues (348 in total) associated with potato cultivation and livestock farming activities in soils of Páramo ecosystems (Cruz Verde and El Verjón) in Cundinamarca, Colombia. Soil samples are from areas in the Páramo under potato crops and livestock farming, at two different altitudes: 3300 m a.s.l. (meters above sea level) and 2900 m a.s.l.; and then, the physical-chemical properties, heavy metals, and pesticide content were determined in each sample. The results showed that none of the soils evaluated exceeded the concentrations of heavy metals permitted by the normativity that was analyzed. On the other hand, we found the presence of the fungicide dimethomorph (0.27 mg kg-1) in soils under potato crops at altitudes 1 and 2, fungicide metalaxyl (0.013 mg kg-1) in soils under potato crops at altitude 1, and insecticide thiamethoxam (0.048 mg kg-1) in soils under potato crops at altitude 2. Anyhow, the statistical analysis did not show significant heavy metals contents or pesticide residues in the Páramo soils associated with potato cultivation and livestock farming; nonetheless, there are significant impacts on five of the physicochemical properties of the soils under study (moisture, bulk density, organic carbon, cation exchange capacity, and phosphorus). Although soil physicochemical parameters properties were modified by soil potato crop and cattle raising, these land land-use types did not cause relevant impacts heavy metals and pesticides, which could be due to the specific agricultural practices adopted in the area (Potato-pasture rotation system, with fallow periods of between 7 and 10 years). Finally, this study represents the first report on heavy metals and pesticide residues in Páramo soils.