The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) stands for being the most serious epidemic (so far) of the 21st century. However, only a few computational studies have investigated the molecular mechanisms underlying the neutralization of the spike protein by antibodies of different classes. Hence, bioinformatic methods were employed to unravel the factors contributing to the remarkable neutralization capacity exhibited by specific antibodies. Initially, crystallographic structures of IgA monomeric / dimeric, IgG, and IgM antibodies binding with the receptor-binding domain region of the SARS-CoV-2 spike protein were retrieved. Subsequently, rigid molecular docking and molecular dynamic simulations were performed over 100 ns with explicit water solvation. Lastly, an energy decomposition was conducted to estimate the binding affinity using the last frames from molecular dynamics. The results revealed a higher binding affinity for both monomeric and dimeric forms of IgA antibodies against the spike protein. Additionally, a greater number of hydrogen bonds were observed during their interaction with the spike protein, as well as greater structural instability along the time and especially a more thermodynamically favorable interaction affinity. In this way, the research contributes a small piece to the complex puzzle of understanding the humoral immune response induced by the SARS-CoV-2 virus. SARSCoV2 SARSCoV SARS CoV (SARS-CoV-2 so far st century However classes Hence Initially IgG receptorbinding receptor SARS-CoV- retrieved Subsequently 10 solvation Lastly dynamics Additionally way virus (SARS-CoV- SARS-CoV 1 (SARS-CoV

RESUMO O balanço hídrico é uma ferramenta com diversas aplicações na agricultura, incluindo a avaliação da adequação de um ambiente para o cultivo de uma determinada cultura, através da compreensão de como os recursos hídricos operam no sistema. Esta informação é vital para determinar se a água disponível satisfaz a necessidade da cultura. Assim, objetivou-se calcular o balanço hídrico em um Argissolo Vermelho-Amarelo para o cultivo de Coffea canephora no município de Cruzeiro do Sul, Acre, utilizando uma série histórica de 36 anos para avaliar o potencial e as restrições da cultura de acordo com a água disponível. Os resultados mostraram que, de forma geral, o cultivo de Coffea canephora é adequado para a região de estudo. Os períodos de déficit hídrico e de excesso de água são bem definidos, ocorrendo de abril a agosto e de setembro a março, respectivamente. Verificou-se que apenas a fase de floração do cafeeiro coincide com o período de déficit hídrico na região, exigindo assim irrigação para evitar comprometer essa etapa do desenvolvimento do fruto. Em relação ao Indice de Satisfação da Necessidade de Água (ISNA), observou-se que, quando calculado em uma escala mensal, indica baixo risco climático para o cultivo de Coffea canephora na região. No entanto, quando calculado em uma escala diária, o ISNA indica risco climático médio a alto para o cultivo durante vários períodos. O ISNA mostrou ser uma ferramenta adequada para a tomada de decisão quanto à adoção de técnicas de irrigação. agricultura sistema Assim objetivouse objetivou VermelhoAmarelo Vermelho Amarelo Sul Acre 3 geral estudo definidos março respectivamente Verificouse Verificou fruto ISNA, , (ISNA) observouse observou mensal entanto diária (ISNA

ABSTRACT Water balance is a tool that has various applications in agriculture, including assessing whether an environment is suitable for growing a specific crop by providing information on how water resources function in the system. This information is essential for determining whether the available water satisfies the crop’s demand. Thus, the objective of this work was to calculate the water balance of Typic Hapludults for growing coffee (Coffea canephora) crops in Cruzeiro do Sul, Acre, Brazil, using a 36-year historical series to assess the potential and limitation of the crop according to the water availability. The results showed that coffee crops are, in general, suitable for growing in the study region. Water deficit and water surplus periods are well-defined, from April to August and September to March, respectively. Flowering was the only stage of coffee crops that coincides with the water deficit period in the region; thus, irrigation is necessary to prevent compromising this stage and fruit development. The Water Requirement Satisfaction Index (WRSI), calculated on a monthly basis, indicates a low climate risk for coffee crops in the region. However, when calculated on a daily basis, the WRSI shows a medium to high climate risk for coffee crops in several periods. The WRSI proved to be an adequate tool for assisting in decision-making regarding the adoption of irrigation. agriculture system s demand Thus Coffea canephora Sul Acre Brazil 36year year 36 availability general region welldefined, welldefined well defined, defined well-defined March respectively thus development WRSI, , (WRSI) basis However decisionmaking decision making 3 (WRSI

ABSTRACT The search for more sustainable systems of rice cultivation, especially in relation to water use, has included the evaluation of more-efficient irrigation systems in addition to alternative water sources. The aim of this study was to conduct a phytosociological survey of weeds in rice crops irrigated by subsurface drip with different concentrations of treated dairy effluent, maintaining the soil moisture at saturation or field capacity. A pilot scale experiment was carried out in a protected environment using a randomised block design in a 5 x 2 factorial scheme, with four replications. The IAC 301 cultivar (Arborio rice) was chosen. The phytosociological surveys were carried out on four different dates, and considered the composition as well as the distribution of plant species in each of the applied treatments, using the importance value index (IVI) to evaluate the influence of each treatment. The results showed that cultivating irrigated rice, giving priority to water management, altered the ecology of invasive plants. Fourteen weed species were identified, distributed over 10 families. The effluent dose did not alter the incidence of invasive plants, and only at the final evaluation was there a reduction in the IVI value at effluent concentrations of 50% and 75%. For soil moisture, the highest IVI values occurred on the first two days of the survey under saturated conditions; this result was reversed closer to plant maturity, when the IVI values were higher at field capacity. cultivation use moreefficient efficient sources capacity scheme replications 30 Arborio chosen dates treatments (IVI treatment management plants identified 1 families 50 75 75% conditions maturity 3 7

ABSTRACT Arbuscular mycorrhizal fungi increase water and nutrient absorption from the soil by plants. However, its benefits to plants vary depending on the inoculated species. This study aimed to determine the influence of different species of mycorrhizal fungi on the development and productivity of grain sorghum cultivars. The experiment was conducted in a greenhouse in a completely randomized design in a 2 x 5 factorial scheme, consisting of two sorghum cultivars (BRS 310 and BRS 330) and five treatments (control without inoculation and four species of arbuscular mycorrhizal fungi: Gigaspora margarita, Glomus formosanum, Acaulospora scrobiculata, and Scutellospora pellucida), with four replications. Plant height, stem diameter, leaf area, length, volume, specific surface area, root diameter, shoot dry mass, root dry mass, thousand-grain weight, grain productivity, colonization, dependence, and mycorrhizal efficiency were evaluated. The results showed that inoculation with the species S. pellucida induced higher root and shoot development of plants of the cultivar BRS 310, as well as higher productivity of sorghum grains. The cultivar BRS 330 showed higher root development when inoculated with the species G. formosanum and a higher shoot development when inoculated with the species A. scrobiculata. Mycorrhizal dependence for grain productivity was low and varied with the inoculated species of mycorrhizal fungi. The mycorrhizal efficiency for shoot dry mass was higher with the inoculation of A. scrobiculata and S. pellucida in the cultivar BRS 310 and A. scrobiculata and G. margarita in the cultivar BRS 330. However scheme 31 control pellucida, , pellucida) replications height diameter area length volume thousandgrain thousand weight colonization evaluated S grains 33 G A 3

RESUMO Na agricultura irrigada, é comum a aplicação de água no solo cultivado sem critério, resultando em uso ineficiente ou não otimizado da água. Em muitos casos, a relação solo-água-planta, bem como as potencialidades e limitações dos sistemas de irrigação são ignoradas. A agricultura irrigada sustentável requer o desenvolvimento de um sistema de monitoramento da umidade do solo que evite a perda de água e melhore a eficiência do uso. O objetivo deste estudo foi desenvolver e avaliar a eficiência de um sistema inteligente de monitoramento da umidade do solo. O sistema é composto por duas estações: a primeira coleta os dados sobre parâmetros de umidade aparente do solo usando sensores, enquanto a segunda transmite esses dados para uma estação de processamento central. O sistema determina precisamente os valores atuais de umidade do solo, permitindo estimar o volume de água de irrigação necessário para atender à demanda hídrica da cultura com base na capacidade de campo. Os resultados da curva de calibração dos sensores indicam que o sistema pode medir com precisão a umidade do solo atual, auxiliando no manejo da irrigação. Para áreas irrigadas em condições de solo não saturado, recomenda-se o uso de tensiômetros devido à sua maior confiabilidade entre a capacidade de campo e o ponto de murcha permanente, garantindo práticas de irrigação mais precisas. critério casos soloáguaplanta, soloáguaplanta planta, planta solo-água-planta ignoradas estações central atual saturado recomendase recomenda se permanente precisas

ABSTRACT Water application to cultivated soil is often done without careful consideration in irrigated agriculture, leading to inefficient or suboptimal water usage. In many instances, the intricate relationship between soil, water, and plants, as well as the potential and limitations of irrigation systems, is overlooked. Sustainable irrigated agriculture necessitates the development of a soil moisture monitoring system that curtails water loss and enhances overall efficiency. This study aimed to develop and assess the efficiency of an intelligent system for monitoring soil moisture. The system comprises two stations: the first collects data on apparent soil moisture parameters using sensors, while the second transmits this data to a central processing station. The system precisely determines current soil moisture values, enabling estimation of the required irrigation water volume to meet the crop’s water demand based on field capacity. Results from the calibration curve of the sensors indicate that the system can measure current soil moisture precisely, aiding in irrigation management. For irrigated areas under unsaturated soil conditions, it is recommended to use tensiometers due to their higher reliability between field capacity and permanent wilting point, ensuring more accurate irrigation practices. usage instances plants systems overlooked stations station values crops crop s management conditions point practices

Abstract Textile sludge is a waste from the effluent treatment of textile laundries and its incorporation into alternative materials has been proposed as a possibility for its disposal. A systematic search was carried out in literature from this perspective, aiming to observe concentrations of waste material and its preparation, matrices used, technological performance and immobilization of textile waste. The matrices used were mortars, concretes and ceramic bricks, in general, deleterious effects were observed on mechanical characteristics of the materials produced. In concrete and mortars, the fineness had an impact on increase in water demand, which increased mixtures porosity; and organic matter and heavy metals, in cement hydration. Recent studies therefore proposed waste material pre-treatment as a favorable alternative. Increases in porosity also occurred in ceramic bricks, however, due to high organic matter content. Regarding waste immobilization, cementitious materials showed satisfactory performance; ceramic bricks, on the other hand, obtained some results outside the normative limits. Therefore, it is necessary to expand discussions regarding the pre-treatment carried out on textile sludge, as well as its impacts on mechanical and environmental performance. disposal perspective preparation mortars bricks general produced demand metals hydration pretreatment pre however content hand limits Therefore

Resumo Olodo têxtil é um resíduo do tratamento do efluente das lavanderias têxteis e sua incorporação em materiais alternativos tem sido proposta como possibilidade para sua destinação. Foi realizada uma busca sistemática na literatura nesta perspectiva, visando observar as concentrações de material residual e seu preparo, as matrizes utilizadas, o desempenho tecnológico e imobilização do resíduo têxtil. As matrizes empregadas foram argamassas, concretos e tijolos cerâmicos, sendo observados, de maneira geral, efeitos deletérios nas características mecânicas dos materiais produzidos. Em concretos e argamassas, a finura impactou no aumento da demanda de água, o que elevou a porosidade das misturas; e a matéria orgânica e metais pesados, na hidratação do cimento. Estudos recentes propuseram, então, o pré-tratamento do material residual como uma alternativa favorável. Incrementos na porosidade também ocorreram nos tijolos cerâmicos, porém, devido ao elevado teor de matéria orgânica. Quanto a imobilização do resíduo, os materiais cimentícios apresentaram desempenho satisfatório; já os tijolos cerâmicos, obtiveram alguns resultados fora dos limites normativos. Portanto, é necessário ampliar as discussões quanto ao pré-tratamento realizado no lodo têxtil, bem como seus impactos no desempenho mecânico e ambiental. destinação perspectiva preparo utilizadas argamassas cerâmicos observados geral produzidos água misturas pesados cimento propuseram então prétratamento pré favorável porém satisfatório normativos Portanto ambiental

Resumo O presente estudo avaliou a incorporação de finos de rocha granítica (GRP) e areia artificial (MS) em argamassas auto-adensáveis (SCM), visando adequação das características reológicas. Foram analisadas SCMs com relações água/cimento de 0,42, 0,46 e 0,63, teores de GRP de 17%, 20% e 40%, respetivamente, e substituição volumétrica de 50% da areia natural por MS. Para avaliar o desempenho das SCMs, foram realizados ensaios de mini V-Funnel e mini Slump, além da caraterização físico-mecânica. A distância de separação interpartículas e a espessura máxima da pasta também foram analisadas e concluiu-se que o teor de GRP é o parâmetro de maior influência no consumo de superplastificante e no tempo de escoamento das misturas. Com a incorporação de GRP, a viscosidade da argamassa foi ajustada sem a necessidade de adição de agentes modificadores de viscosidade, aumentando o tempo de escoamento, enquanto a substituição parcial de NS por MS resultou numa diminuição deste parâmetro. Além disso, a incorporação simultânea de GRP e MS aumentou a densidade das misturas, promovendo aumento da resistência à compressão em até 29% e da resistência à tração na flexão em até 19%, apesar da redução de cerca de 40% do volume de cimento. (GRP (MS autoadensáveis auto adensáveis SCM, SCM , (SCM) reológicas águacimento água cimento 042 0 42 0,42 046 46 0,4 063 63 0,63 17 17% 20 40 respetivamente 50 VFunnel V Funnel Slump físicomecânica. físicomecânica físico mecânica. mecânica físico-mecânica concluiuse concluiu se misturas disso 29 19 19% (SCM 04 4 0, 06 6 0,6 1 2 5

Abstract The study assessed the use of granitic rock powder (GRP) and manufactured sand (MS) in self-compacting mortars (SCM) to achieve desired rheological properties. Different water/cement ratios of 0.42, 0.46, and 0.63 were used with partial replacement of cement volume by GRP at levels of 17%, 20%, and 40%. Additionally, a volumetric replacement of 50% natural sand with MS was studied. The performance of SCMs was evaluated using mini V-Funnel and mini Slump Tests, as well as physical-mechanical characterization. It was found that GRP content significantly influenced superplasticizer consumption and flow time without requiring additional viscosity modifiers while incorporating MS decreased flow time parameter. Furthermore, simultaneous incorporation of GRP and MS increased mixture density by up to 14% improved compressive strength by up to 29%, and flexural tensile strength by up to19%. (GRP (MS selfcompacting self compacting SCM (SCM properties watercement water 042 0 42 0.42 046 46 0.46 063 63 0.6 17 17% 20 20% 40 40% Additionally 50 studied VFunnel V Funnel Tests physicalmechanical physical mechanical characterization parameter Furthermore 14 29 29% to19 to19% 04 4 0.4 06 6 0. 1 2 5 to1

Summary: Currently, agricultural activity is constantly threatened by the effects of climate change and radical expression of environmental factors as irregular rainfall distribution responsible for water availability and deficit. These factors generate water stress in productive systems, whose negative effect is reflected on morphological, physiological and biochemical aspects of vegetative growth. The use of biostimulants arises as a strategy to counteract this impact, improving crop efficiency in the use of resources and generating responses, as metabolite production, among other substances that mitigate the effects of oxidative stress. In this context, waxes, hydrogen peroxide (H2O2), salicylic acid (SA) and ALGAENZIMSMR were used on raspberry plants subjected to moderate water stress (-0. 8 MPa) to evaluate the fruit response in aspects of vegetative growth, physiological and biochemical quality. For the establishment, a completely randomized design was used with 5 treatments: Green Cover as 5 mL L-1, H2O2 10-4 M, salicylic acid 0.27 mM, ALGAENZIMSMR 7.5 mL L-1 and the control with 50% recovery of the transpired volume as well as water potential similar to the rest of plants and 4 replicates. The results showed that waxes, SA and algal extract increased the photosynthetic rate; the four treatments increased root length; waxes increased root height; and H2O2 increased root biomass. Compared to the control, higher levels of vitamin C and anthocyanins were produced in fruits - a very important aspect due to the functionality of these compounds in human health. Therefore, the use of these biostimulants are a very useful tool for crop management in environments with water restriction.

Resumen: En la actualidad la actividad agrícola se ve amenazada constantemente por los efectos del cambio climático y la expresión radical de los factores ambientales, como la irregularidad en la distribución pluvial responsable de la disponibilidad del agua y déficit, que genera estrés hídrico en los sistemas productivos, cuyo efecto negativo se refleja en aspectos de crecimiento vegetativo, morfológicos, fisiológicos y bioquímicos. El uso de bioestimulantes surge como estrategia para contrarrestar este impacto, mejorando la eficiencia de los cultivos en el uso de los recursos y generar respuestas, como la producción de metabolitos entre otras sustancias, que mitigan los efectos del estrés oxidativo. Bajo este contexto se planteó el uso de ceras, peróxido de hidrogeno (H2O2), ácido salicílico (AS) y algaenzims, sobre plantas de frambuesa sometidas a estrés hídrico moderado (-0.8 MPa) con el objetivo de evaluar la respuesta en aspectos de crecimiento vegetativo, fisiológicos y calidad bioquímica de frutos, para el establecimiento se empleó un diseño completamente al azar con 5 tratamientos: greencover as® 5 mL L-1, H2O2 10-4 M, ácido salicílico 0.27 mM, algaenzims® 7.5 mL L-1 y el control con recuperación del 50% del volumen transpirado y con potencial hídrico similar al resto de plantas y 4 repeticiones. Como resultados se obtuvo que las ceras, AS y el extracto de algas incrementaron la tasa fotosintética, los cuatro tratamientos aumentaron la longitud de raíces, las ceras la altura, y el H2O2 la biomasa de raíz. Por otro lado, en comparación con el control, se produjeron mayores niveles de vitamina C y antocianinas en frutos, un aspecto muy importante por la funcionalidad de estos compuestos en la salud humana. Por lo tanto, el uso de estos bioestimulantes se puede visualizar como una herramienta de gran utilidad para el manejo de cultivos en ambientes con restricción de agua.

Resumen:El presente estudio analiza los principales factores que tienen influencia en el consumo de agua potable, así como los patrones de consumo horario del recurso hídrico en zonas residenciales de la parroquia El Rosario. Se aplicó un estudio de caracterización urbanística por medio de fichas técnicas y análisis estadístico que denotan 3 estratificaciones en el sector (B, C y D). Se aplicaron encuestas para conocer factores que inciden en el consumo de agua potable y se realizó el registro horario de lecturas de 219 medidores de agua durante 24 horas los 7 días de la semana. El consumo de agua potable registrado presenta incrementos que tienen dependencia a factores como el número de usuarios que disponen del servicio, tipo de residencia, unidades sanitarias en uso y otras características externas. Se obtuvieron curvas de consumo horarias para cada red de distribución y los coeficientes de variación de consumo horario máximos y mínimos. Los caudales máximos ocurren a las 13h00 con 94.76 l/h y a las 19h00 con 73.46 l/h, el coeficiente máximo de variación de consumo horario (Kh_max) es de 3.44, valor que sobrepasa lo establecido en la normativa nacional vigente CPE INEN 5 (1992); los valores de los coeficientes máximos de cada barrio se presentan mediante digitalización georreferenciada.

Abstract:This study analyzes the main factors that influence drinking water consumption, as well as the hourly water consumption patterns in residential areas of El Rosario parish. A study of urban characterization was applied by means of technical data sheets and statistical analysis that showed 3 stratifications in the sector (B, C and D). Surveys were conducted to determine the factors that affect drinking water consumption, and an hourly record was made of readings of 219 water meters 24 hours a day, 7 days a week. The consumption of drinking water recorded showed increases that depend on factors such as the number of users who have the service, type of residence, sanitary units in use and other external characteristics. Hourly consumption curves were obtained for each distribution network and the coefficients of variation of maximum and minimum hourly consumption. The maximum flows occur at 13h00 with 94.76 l/h and at 19h00 with 73.46 l/h, the maximum coefficient of variation of hourly consumption (Kh_max) is 3.44, a value that exceeds that established in the current national regulation CPE INEN 5 (1992); the values of the maximum coefficients of each neighborhood are presented through georeferenced digitalization.

Abstract Introduction: Reservoirs are conceived as a set of interactions in which physical, chemical, and biological instability determines changes in the density of planktonic communities. Objective: To evaluate the instability of phytoplankton and zooplankton, and their interactions with environmental factors in four tropical Andean reservoirs with different trophic status. Methods: Physical and chemical variables and phytoplankton and zooplankton densities were measured between 2010-2018 in the oligotrophic reservoirs Punchiná and San Lorenzo and between 2013 and 2015 in the hypereutrophic reservoir Porce II and in the eutrophic Porce III reservoir (total N = 248). The Factor Shaping Community Assemblages (FCA) was used to calculate environmental and biotic instability as well as their interaction. Results: High environmental and biological instability was observed in the studied reservoirs. Oxygen saturation, pH, total nitrogen, water temperature, nitrites, total phosphorus (only for zooplankton), and total solids were the abiotic variables with the greatest contribution to planktonic instability, regardless of trophic state. Particularly, Cryptomonas sp., Aulacoseira sp., Cyclotella sp., Dinobryon sp., Nephrocytium sp., Tetraëdron caudatum and Oscillatoria sp. had the greatest influence on the instability of various rotifer taxa and some copepods. Conclusions: Regardless of trophic state, pH dynamics, nutrients availability, amount of suspended solids and the availability of gases, such as dissolved oxygen, mainly determined the instability of phytoplankton and to a lesser extent that of zooplankton. In the oligotrophic reservoirs, zooplankton instability was mainly influenced by highly palatable algae with no toxicity, and in reservoirs highly enriched, the instability was influenced by algae with low nutritional quality and difficult to ingest and manipulate.

Resumen Introducción: los embalses deben ser concebidos como un conjunto de interacciones, donde la inestabilidad física, química y biológica determinan cambios en la densidad de las comunidades planctónicas. Objetivo: Evaluar la inestabilidad del fitoplancton y zooplancton y su interacción con factores ambientales en cuatro embalses tropicales andinos con diferente estado trófico. Métodos: Se analizaron datos de variables físicas y químicas y de las densidades del fitoplancton y del zooplancton, medidas entre 2010-2018, en los embalses oligotróficos Punchiná y San Lorenzo y, entre 2013 y 2015, en el embalse hipereutrófico Porce II y en el embalse eutrófico Porce III (total N = 248). Se empleó el Factor Shaping Community Assemblages (FCA), para calcular la inestabilidad biótica y ambiental y la interacción entre estas. Resultados: En los embalses estudiados hubo una alta inestabilidad ambiental y biológica. El pH, la saturación de oxígeno, el nitrógeno total, la temperatura del agua, los nitritos, el fósforo total (solo para el zooplancton) y los sólidos totales, son las variables abióticas con mayor aporte a la inestabilidad planctónica, independientemente del estado trófico. Particularmente, Cryptomonas sp., Aulacoseira sp., Cyclotella sp., Dinobryon sp., Nephrocytium sp., Tetraëdron caudatum y Oscillatoria sp., tuvieron mayor influencia sobre la inestabilidad de diferentes taxones de rotíferos y de algunos copépodos. Conclusión: Independiente del estado trófico, la dinámica del pH, la disponibilidad de nutrientes, la cantidad de sólidos suspendidos y la disponibilidad de gases como el oxígeno disuelto determinaron principalmente la inestabilidad del fitoplancton, y en menor medida la del zooplancton. En los embalses oligotróficos la inestabilidad del zooplancton es influenciada principalmente por algas altamente apetecibles con toxicidad nula, y en embalses altamente enriquecidos la inestabilidad fue influenciada por algas con baja calidad nutricional y de difícil ingestión y manipulación.

Abstract Introduction: The brackish lagoons are ecosystems with great diversity and possibilities for human use. Therefore, the knowledge about phytoplankton needs to be improved to understand its real impact. Objective: To relate the Mandinga’s Lagoon phytoplankton to the limnological conditions during the dry and wet seasons. Methods: The material was collected in three stations: Isla Conchas (ICO), Mandinga Chica (MCH) and Isla del Amor (IA) during the dry (March 2018) and wet (September 2017 and 2018) seasons. The limnological analysis included ten abiotic variables, and the phytoplankton was analyzed by the Utermöhl method. Data was analyzed with the Shannon index (H') and Canonical Correspondence Analysis (CCA). Results: 136 species were identified: 68.4 % Heterokontophyta, 22.8 % Dinoflagellata, and 5.9 % Cyanobacteria; with 40 euryhaline and 96 stenohaline. The most abundant species were: Bacillaria paxillifera, Chaetoceros compressus, Coscinodiscus rothii, and Chaetoceros atlanticus. The highest abundance was in ICO (dry) and the lowest in MCH (wet), with 307 x 103 and 76 x 103 cells/ml, respectively; the H' ranged from 1.31 to 0.70 bits/ind. The CCA showed a relationship between salinity and dissolved oxygen with C. rothii and Ceratoneis closterium. The phosphates were associated with B. paxillifera, C. atlanticus, and Podosira stelligera. The nitrate, water temperature and pH were related to Tripos hircus, T. furca, Diploneis bombus, and Merismopedia elegans. In contrast, Skeletonema costatum, Cocconeis scutelum, and Nitzschia bicapitata did not correlate with the limnological variables. Conclusions: The Mandinga’s Lagoon is a shallow, euryhaline and well-oxygenated ecosystem. The dominance of diatoms and dinoflagellates was evidenced by their ability to survive in different salinities and temperatures. It is recommended monitor phytoplankton, in particular Microcystis wesenbergii, B. quinquecornis, Pseudo-nitzschia cf. pungens, and P. cf. pseudodelicatissima as they are harmful algae.

Resumen Introducción: Las lagunas salobres son ecosistemas de alta diversidad y con posibilidades para uso humano. Por lo que es necesario mejorar el conocimiento del fitoplancton para entender su impacto real. Objetivo: Relacionar el fitoplancton de la Laguna Mandinga con las condiciones limnológicas durante épocas de secas y lluvias. Métodos: El material se recolectó en tres estaciones: Isla Conchas (ICO), Mandinga Chica (MCH) e Isla del Amor (IA) en secas (marzo 2018) y lluvias (septiembre 2017 y 2018). El análisis limnológico incluyó diez variables abióticas, además del fitoplancton mediante el método de Utermöhl. Los datos fueron analizados por el índice de Shannon (H') y Correspondencia Canónica (ACC). Resultados: Análisis de 136 especies; 68.4 % Heterokontophyta, 22.8 % Dinoflagellata, 5.9 % Cyanobacteria; con 40 eurihalinas y 96 estenohalinas. Las especies más abundantes fueron: Bacillaria paxillifera, Chaetoceros compressus, Coscinodiscus rothii y Chaetoceros atlanticus. La mayor abundancia se registró en ICO (secas) y la menor en MCH (lluvias) con 307 x 103 y 76 x 103 cell/ml, respectivamente. El H' osciló entre 1.31 y 0.70 bits/ind. El CCA mostró una relación entre salinidad y oxígeno disuelto con C. rothii y Ceratoneis closterium. Los fosfatos se asociaron con B. paxillifera, C. atlanticus y Podosira stelligera. Los nitratos, temperatura y pH se correlacionaron con Tripos hircus, T. furca, Diploneis bombus y Merismopedia elegans. Mientras, Skeletonema costatum, Cocconeis scutelum y Nitzschia bicapitata no presentaron correlación con las variables limnológicas. Conclusiones: La Laguna Mandinga es un ecosistema somero, eurihalino y bien oxigenado. La dominancia de diatomeas y dinoflagelados se evidenció por su capacidad para sobrevivir en diferentes concentraciones de salinidad y temperatura. Sugerimos monitorear al fitoplancton por la presencia de Microcystis wesenbergii, B. quinquecornis, Pseudo-nitzschia cf. pungens y P. cf. pseudodelicatissima ya que pueden formar proliferaciones dañinas.

The water resources within the lower section of the Upper Vaal catchment, where the Vaal Barrage is situated, are highly utilised and developed, and water quality regulation has become a contested space between resource users and the regulators. The credibility and scientific defensibility of discharge standards in water-use licences (WULs), the relationship between upstream and downstream waste loads, the relationship between flows and water quality standards in WUL, and the water quality components of the resource quality objectives (RQOs) are being contested. This study explores the perceptions and motivations underlying these contestations as a contribution to scientific understanding of water quality management in a highly developed system. Perceived unrealistic RQOs, perceived lack of scientific credibility of the methods for deriving water quality standards in WUL, data inadequacy, as well as poor institutional capacity were identified as the top motivations for contesting applicable regulatory instruments in the catchment. Punitive measures, incentives, and education and awareness-raising were identified as key to accelerating compliance. Overall, this paper contributes to our general understanding of the intricacies of water quality management within a contested space. SIGNIFICANCE: Water quality management in South Africa is increasingly becoming a contested space, particularly in catchments that are highly developed and utilised. The findings in this study imply that (1) there is a need for a multi-pronged approach to increase water quality compliance, (2) there is a need for trust within the regulatory system to foster confidence among actors and stakeholders, and (3) transparent, open processes and scientifically credible and defensible methods, and data are needed for deriving standards in water-use licences (WULs).

Remote areas that lack conventional water-provisioning infrastructure often rely on rainwater harvesting, rivers, pans, reservoirs and borehole-extracted water to meet domestic water requirements. These water sources often have poor microbial quality and chemical composition, the quality of which is not routinely monitored. This study explored citizen science as a tool for Engaged Research and Responsible Research and Innovation, detailing the co-creation of a sustained community-based water quality monitoring program in collaboration with communities in villages in Amakhala Game Reserve (Eastern Cape, South Africa). Without access to other water sources, participants predominantly used rainwater for drinking and cooking (80%), while borehole water was mainly used for cleaning and gardening due to its salty or bitter taste. A hydrogen sulfide (H2S) water testing kit was used by the citizen scientists to monitor the water quality. The H2S kits were effective in estimating bacterial contamination, showing a proportional relationship with Colilert® test results conducted in a laboratory. The alignment observed between community-based monitoring results and those derived from scientist-led testing underscores the value of data produced through citizen science initiatives. Sustained participant engagement throughout this research reflected a sense of community empowerment through access to tools that inform their decision-making around water use and treatment as well as investment in the research, indicative of the perceived relevance of the research to community interests. This integration of transdisciplinary data sources holds promise for informing evidence-based decision-making processes, facilitating more effective and contextually informed water management strategies that value and integrate community perspectives alongside scientific insights. SIGNIFICANCE: Drawing on the principles of Engaged Research and Responsible Research and Innovation, we applied citizen science tools to engage researchers and communities in the co-development of a water quality monitoring program. In addressing a specific area of concern, raised by the remotely situated community around the need for knowing their water quality, the project successfully trained communities in applying water testing tools and fostered agency in decision-making around water treatment. Combined with continuous feedback and communication loops, a high rate of continuity was sustained among the participants.

ABSTRACT Having in mind food security and the fact that basil (Ocimum basilicum L.) is used as fresh seasoning, the development of innovative technologies for its cultivation is required. This study aimed to isolate and characterize plant growth-promoting rhizobacteria (PGPR) isolates from basil rhizospheric soil and monitor the effects of their application on basil growth under different water stress conditions. Isolation, determination of isolates biochemical and PGP properties, evaluation of isolates influences on seed germination and parameters of growth of basil plant, growing under well-watered conditions (70% water holding capacity, WHC), under water deficit stress (35% WHC), and flooded conditions (95% WHC), were done. A total of five representative bacterial isolates were selected: Two Azotobacter isolates (A13, A14), one Pseudomonas isolate (P57), and two Bacillus isolates (B79, B82). The results of this experiment revealed that rhizospheric bacteria of O. basilicum L. var. minimum have multiple biochemical and PGP properties. The most intensive reactions on tested abiotic stressors - drought (higher total phenolics, reduced glutathione, and malondialdehyde content) and flooding (higher superoxide dismutase activity) - were from basil plants inoculated with Pseudomonas sp. P57 isolate, yet along with Azotobacter sp. isolate A13. The highest number of germinated seeds was obtained with the A13 isolate (96.0%), while the highest response for vigour index was observed with Azotobacter isolates (7200.0% and 5628.0%). In well-watered conditions, basil mass inoculated with P57 was 34.2% higher than control. In drought-stressed conditions, plant mass inoculated with A13 isolate was 90% higher than control. In flooded-stressed conditions, the plant mass inoculated with Azotobacter and Pseudomonas isolates increased by more than 100%.

ABSTRACT Heat and drought stress, which often co-occur due to water evaporation, are two major abiotic factors limiting the production of rice (Oryza sativa L.) It is crucial to enhance understanding of the effects of these abiotic stresses in rice, particularly for rice-producing countries like Malaysia, which has yet to achieve rice self-sufficiency. This greenhouse study was conducted to evaluate the morphological changes of two important Malaysian cultivars (‘MR219’ and ‘MR303’) at vegetative, reproductive, and ripening stages, as well as their physiological response and yield components under normal (control), heat, drought, and combined heat-drought stress conditions. Individual heat stress greatly influenced rice growth and yield, with significant differences (p < 0.01) observed across all examined parameters except the grain to leaf area index ratio (GtoLAI). Conversely, individual drought stress mostly affected yield-related parameters, with significant differences (p < 0.01) in grain weight (GW), harvest index (HI), and percentage of filled grain (%FG). Interestingly, the combined stresses in this study did not significantly affect plant height (PH) for all growth stages and most yield-related traits (HI, GW, and GtoLAI). The majority of the significant changes (p < 0.01) were observed on physiological traits, including chlorophyll a (Chl A) and b (Chl B). We found a positive correlation between HI and %FG (R2 = 0.3974**) under heat and drought stress, indicating that improving either of these traits can boost rice production. Collectively, our study revealed that the individual effects of heat and drought on rice growth and yield can differ from the effects of combined stress.