Abstract Invasive exotic plant species cause serious impacts on the structure and functioning of invaded ecosystems, leaving native species at a disadvantage. Eucalyptus globulus and Pinus halepensis are two species characterized by their wide distribution and high competitive ability. The objective of the study was to compare the allelopathic effect of leaf litter leachate from E. globulus and P. halepensis on the germination, growth and diversity of high Andean wild plant species. Thirty soil samples were collected from the first 10 cm from 1 m2 quadrats. The leachate negatively affected the germination, growth and diversity of wild plant species, particularly eucalyptus leachate. As this is one of the few studies carried out in high Andean areas, it is necessary to carry out studies in natural conditions and on larger time scales, to more accurately evaluate the effects on biodiversity.

Resumen Las especies de plantas exóticas invasoras causan graves impactos en la estructura y funcionamiento de los ecosistemas invadidos, dejando en desventaja a las especies nativas. Eucalyptus globulus y Pinus halepensis, son dos especies caracterizadas por su amplia distribución y alta habilidad competitiva. El objetivo del estudio fue comparar el efecto alelopático del lixiviado de la hojarasca de E. globulus y P. halepensis sobre la germinación, crecimiento y diversidad de especies de plantas silvestres altoandinas. Se colectaron 30 muestras de suelo de los primeros 10 cm a partir de cuadrantes de 1 m2. Los lixiviados afectaron de forma negativa la germinación, crecimiento y diversidad de especies de plantas silvestres, particularmente el lixiviado de eucalipto. Al ser este uno de los pocos estudios hechos en zonas altoandinas, es necesario la realización de estudios en condiciones naturales y en mayores escalas temporales, para evaluar con mayor precisión los efectos sobre la biodiversidad.

ABSTRACT Entomopathogenic fungi (EP) and plant growth-promoting bacteria (GBP) in combination with liquid organic fertilizers can be the ecological alternative to complement chemical fertilization, and improve the nutrition and yield of melon (Cucumis melo L.). The objective of the study was to evaluate Metarhizium anisopliae, Beauveria bassiana and a consortium of BPCV (P. flurescens, B. subtilis, A. brasilence and B. mucilaginosus) in combination with vermicompost leachate (LVE) and goat manure biol (BEC). ) in the foliar nutritional concentration, plant growth, fruit size, yield and colonization of these microorganisms in the melon rhizosphere. An experimental design was used in complete randomized blocks, with six treatments (HE + LVE, BPCV + LVE, HE + BEC, BPCV + BEC, LVE and BEC) and a control. It was found that with the BPCV + BEC treatment, leaf N and Ca concentration increased by 9.4% and 21.3%, respectively, root dry weight by 45.8%, fruit polar diameter by 20.3% and fruit weight in 31.2% in relation to the control. While plants treated with HE + BEC and BPCV + BEC, compared to the control, increased leaf P concentration from 9.8 to 10.2%, stem diameter from 27.2% to 28.5% and yield from 12.4% to 12.6%. Both HE and BPCV colonized soil particles from the plant rhizosphere, which positively influenced melon yield. These results are beneficial for melon producers, both to increase crop yield and to complement chemical fertilization in an ecological way in the production system.

RESUMEN Los hongos entomopatógenos (HE) y las bacterias promotoras del crecimiento vegetal (BPCV) en combinación con abonos orgánicos líquidos puede ser la alternativa ecológica para complementar la fertilización química, y mejorar la nutrición y rendimiento de melón (Cucumis melo L.). El objetivo del estudio fue evaluar Metarhizium anisopliae, Beauveria bassiana y un consorcio de BPCV (P. flurescens, B. subtilis, A. brasilence y B. mucilaginosus) en combinación con lixiviado de vermicompost (LVE) y biol de estiércol de cabra (BEC) en la concentración nutrimental foliar, crecimiento de planta, tamaño de fruto, rendimiento y colonización de estos microorganismos en la rizosfera de melón. Se utilizó un diseño experimental en bloques completos al azar, con seis tratamientos (HE + LVE, BPCV + LVE, HE + BEC, BPCV + BEC, LVE y BEC) y un testigo. Se encontró que con el tratamiento BPCV + BEC aumentó la concentración de N y Ca foliar en 9,4% y 21,3%, respectivamente, peso seco de raíz en 45,8%, diámetro polar de fruto en 20,3% y peso de fruto en 31,2% en relación con el testigo. Mientras que las plantas tratadas con HE + BEC y BPCV + BEC, en comparación con el testigo, incrementaron la concentración de P foliar de 9,8 a 10,2%, diámetro de tallo de 27,2% a 28,5% y rendimiento de 12,4% a 12,6%. Tanto los HE y BPCV colonizaron partículas de suelo de la rizosfera de la planta, lo que influyó positivamente en el rendimiento de melón. Estos resultados son beneficiosos para los productores de melón, tanto para aumentar el rendimiento del cultivo como para complementar la fertilización química de manera ecológica en el sistema productivo.

Abstract: The objective of this study was to characterize the morphological composition of five populations of native maize and estimate their yields using agricultural practices without the use of agrochemicals. The study conducted in 2021, in the municipality of Cintalapa, Chiapas, within the experimental field of the Regional Academic Center of the Antonio Narro Autonomous Agrarian University. The five populations of native maize were provided by farmers from different regions of the state, with prior informed consent. The Agricultural practices consisted of using plant extracts and potassium soap with neem extract (Azadirachta indica) to prevent and combat pests. For fertilization, Californian red earthworm (Eisenia foetida) leachate and bat guano were applied in their commercial presentation. Morphological characters were evaluated with a descriptive statistical analysis considering days to male and female flowering, plant and ear height ear length and diameter, number of rows per ear and number of kernels per row. Grain yield was estimated by the weight of the ear harvested from a random sample of 20 plants per population. Numerical differences of the studied variables were identified, which demonstrates an existing genetic diversity. The populations with the highest yields were Campeón and Olotillo, with 5.37 and 4.4 ton ha-1 (± 1.24), respectively. The data provide information to design native maize conservation strategies through agrochemical-free management.

Resumen: El objetivo de este estudio fue caracterizar morfológicamente cinco poblaciones de maíz nativo y estimar sus rendimientos, empleando prácticas agrícolas sin uso de agroquímicos. El estudio se realizó en el año 2021, en el municipio de Cintalapa, Chiapas, dentro del campo experimental del Centro Académico Regional de la Universidad Autónoma Agraria Antonio Narro. Las cinco poblaciones de maíz nativo fueron proporcionadas por campesinos de diferentes regiones de la entidad, con previo consentimiento informado. Las prácticas agrícolas consistieron en uso de extractos vegetales y jabón potásico con extracto de neem (Azadirachta indica) para la prevención y combate de plagas. Para la fertilización se aplicó lixiviado de lombriz roja californiana (Eisenia foetida) y guano de murciélago en su presentación comercial. Los caracteres morfológicos se evaluaron con un análisis estadístico descriptivo considerando: días de floración masculina y femenina, alturas de planta y mazorca, longitud y diámetro de la mazorca, y número de hileras por mazorca y número de granos por hilera. El rendimiento de grano se estimó mediante el peso de la mazorca cosechada de una muestra aleatoria de 20 plantas por población. Se identificaron diferencias numéricas de las variables estudiadas, lo que demuestra una diversidad genética existente. Las poblaciones que presentaron mayores rendimientos fueron Campeón y Olotillo, con 5,37 y 4,4 ton ha-1 (± 1,24), respectivamente. Los datos aportan información para diseñar estrategias de conservación de maíces nativos con manejo libre de agroquímicos.

Summary: The continuous use of excessive nitrogenous fertilizers generates environmental risks by increasing nitrate accumulation, volatilization and leaching in soil, which causes losses and low efficiencies in the use of nitrogen (N). The objective of the present study is to evaluate the application of nitrogenous nanocomposites (NCN) as a slow-release fertilizer (SRF) in soil and its effect on growth of the lettuce crop. The NCN was prepared by sorption of a cationic surfactant on a bentonite clay. The study was performed in soil columns; the evaluated treatments were ratios of NCN and conventional fertilizer (FC) 25/0, 50/0, 75/0 and 100/0, 0/100, 25/75, 50/50 and 75/25. The variables evaluated were: fresh weight, dry biomass, leaf area, electrical conductivity, NO3- concentration in leachate and leaf, soil plant analysis development (SPAD) and normalized difference vegetation index (NDVI) units, as well as NCN release in deionized water. The results obtained indicate that the NCN treatments equaled the control after 40 days except for the 25/0 treatment that reduced the fresh weight variables by 20% and leaf area by 18% with respect to the 0/100 control. The SPAD and NVDI values did not have significant differences between treatments. The NCN/FC 0/100, 50/50 and 75/25 ratios increased nitrate concentration in leaves by 19%. The 100/0 treatment increased total dry biomass with 48%, 87% root volume and 73% root dry biomass. The results of the release in deionized water confirmed that NCN gradually releases nitrates and in higher amounts than those calculated. Finally, to conclude the nanocomposite material has the potential to be used as a slow-release fertilizer when growth increases. Therefore, nanocomposites could be an alternative to reduce the use of conventional fertilizers and nitrogen losses in soil.

Resumen: El uso continuo de fertilizantes nitrogenados en exceso genera riesgos ambientales al aumentar en el suelo la acumulación, volatilización y lixiviación de nitratos, que provocan pérdidas y baja eficiencia en la utilización de N. En este estudio, el objetivo fue evaluar la aplicación de nanocompuestos nitrogenados (NCN) como fertilizante de liberación lenta en el suelo y su efecto en el crecimiento del cultivo de lechuga. El NCN se preparó por la sorción de un surfactante catiónico en una arcilla de bentonita. El estudio se realizó en columnas de suelo, los tratamientos evaluados fueron relaciones de NCN y fertilizante convencional (FC) 25/0, 50/0, 75/0 y 100/0, 0/100, 25/75, 50/50 y 75/25. Las variables evaluadas fueron: peso fresco, biomasa seca, área foliar, conductividad eléctrica, concentración de NO3 - en lixiviado y hoja, unidades SPAD y NDVI, además de la liberación del NCN en agua desionizada. Los resultados obtenidos indican que después de 40 días los tratamientos con NCN igualaron al control excepto el tratamiento 25/0 que redujo las variables peso fresco 20% y el área foliar 18% con respecto al control 0/100. Los valores de SPAD y NVDI no tuvieron diferencias significativas entre tratamientos. Las relaciones NCN/FC 0/100, 50/50 y 75/25 aumentaron 19% la concentración de nitratos en hojas. El tratamiento 100/0 aumentó biomasa seca total con 48%, 87% el volumen radical y 73% la biomasa seca de raíz. Los resultados de la liberación en agua desionizada confirmaron que el NCN libera gradualmente nitratos y en mayor cantidad que lo calculado. Finalmente, se concluye que el material nanocompuesto tiene el potencial de usarse como fertilizante de lenta liberación al aumentar crecimiento, por lo que podría ser una alternativa para reducir el uso de fertilizantes convencionales y disminuir las pérdidas de nitrógeno en suelo.

RESUMEN Objetivo. En este estudio se evaluó la cinética de crecimiento de consorcios de microalgas marinas y de agua dulce en diferentes concentraciones de lixiviado extraído de un relleno sanitario. Materiales y métodos. Se realizó un diseño experimental por cada consorcio (marino Chlorella marina y Nannochloropsis oculata y de agua dulce Chlorella vulgaris y Ankistrodesmus falcatus) en concentraciones de lixiviado de 5, 10, 15% y un control (0%), con una inóculo principal y tres réplicas para cada concentración (K=4), en cultivo discontinuo. Resultados. Se encontraron diferencias significativas en el crecimiento microalgal a distintas concentraciones de lixiviado para los dos consorcios utilizados (H=12.9768; p<0.05 para microalgas marinas y H=20.0097; p<0.05 para microalgas dulceacuícolas), debido principalmente a un mayor crecimiento en el grupo control. También se encontró una correlación negativa significativa (p<0.01) entre la tasa de crecimiento y la división celular con la concentración de lixiviado, observándose un menor crecimiento en concentraciones superiores al 5% en ambos consorcios. Conclusiones. El consorcio marino logró generar mayor densidad celular, por lo que podría incrementar la efectividad de los procesos de biorremediación de contaminantes, a pesar del efecto negativo observado en mayores cantidades del compuesto.

ABSTRACT Objective. This study evaluated the growth kinetics of marine and freshwater microalgae consortia in different concentrations of leachate extracted from a landfill. Materials and methods. An experimental design was carried out for each consortium (marine Chlorella marina and Nannochloropsis oculata and freshwater Chlorella vulgaris and Ankistrodesmus falcatus) in leachate concentrations of 5, 10, 15% and a control (0%), with one main experiment and three replicates for each concentration (K=4), in batch culture. Results. Significant differences were found in the microalgal growth at different concentrations of leachate for both consortia (H=12.9768; p<0.05 for marine microalgae and H=20.0097; p<0.05 for freshwater microalgae), attributed to a higher growth in the control sample. A significant negative correlation (p<0.01) was also found between leachate concentration and both growth rate and cell division. A lower growth was observed at concentrations above 5% in both consortia. Conclusions. The marine consortium was able to generate a higher cell density, which may increase the effectiveness of the pollutant bioremediation process, despite the negative effect observed at higher amounts of the compound.

Abstract Treatment of landfill leachate is an important environmental issue, especially in developing countries such as Brazil. Advanced oxidation processes (AOPs) have been considered interesting treatment alternatives. In this study, ZnO-TiO2 mixtures were incorporated into a paint polymer matrix and fixed onto supports. Paints were applied by overlapping coat layers on plates, resulting in high film thickness (600 ± 80 µm). Treatment of mature leachate by an AOP was conducted in a plug flow reactor connected to a stirred tank under solar irradiation. The objective was to evaluate the degradation of humic acid (HA) and fulvic acid + humins (FAH). The highest HA and FAH removal efficiencies were 62% ± 4.9% and 16% ± 4.2%, respectively. The kinetic model provided a coefficient of determination (R 2) of 0.974. Rate constants for HA and FAH removal were 2.96 and 1.03 × 10−3 min−1, respectively. Statistical models for HA and FAH degradation had R 2 values of 0.96 and 0.99, respectively. Both approaches indicated that HA degradation is greater at acidic pH and higher TiO2 concentrations. FAH degradation was favored by acidic pH and higher ZnO concentrations. Statistical models showed the same mean difference in conversion between replicate runs of HA and FAH, suggesting a uniform diffusion of fractions through catalysts. issue Brazil AOPs (AOPs alternatives study ZnOTiO2 ZnOTiO TiO ZnO-TiO supports plates 600 (60 8 µm. µm . µm) irradiation (HA FAH. (FAH) 62 49 4 9 4.9 16 42 4.2% respectively 0974 0 974 0.974 296 96 2.9 103 1 03 1.0 10 3 10− min1 min min−1 096 0.9 099 99 0.99 concentrations catalysts 60 (6 (FAH 6 4. 4.2 097 97 0.97 29 2. 1. min− 09 0. (

Resumo O tratamento de chorume de aterro é uma questão ambiental importante, especialmente em países em desenvolvimento como o Brasil. Os processos oxidativos avançados (POA) têm sido considerados interessantes alternativas de tratamento. Neste estudo, misturas de ZnO-TiO2 foram incorporadas a uma matriz polimérica de tinta e fixadas em suportes. As tintas foram aplicadas pela sobreposição de camadas de revestimento em placas, resultando em alta espessura de filme (600 ± 80 µm). O tratamento do lixiviado maduro por um POA foi conduzido em um reator de fluxo contínuo conectado a um tanque de agitação sob irradiação solar. O objetivo foi avaliar a degradação de ácido húmico (HA) e ácido fúlvico + huminas (FAH). As maiores eficiências de remoção de HA e FAH foram 62% ± 4,9% e 16% ± 4,2%, respectivamente. O modelo cinético forneceu um R2 de 0,974. As constantes de velocidade para remoção de HA e FAH foram 2,96 e 1,03 × 10−3 min−1, respectivamente. Os modelos estatísticos para degradação de HA e FAH tiveram valores de R2 de 0,96 e 0,99, respectivamente. Ambas as abordagens indicaram que a degradação do HA é maior em pH ácido e concentrações mais altas de TiO2. A degradação de FAH foi favorecida por pH ácido e maiores concentrações de ZnO. Os modelos estatísticos mostraram a mesma diferença significativa na conversão entre as execuções repetidas, sugerindo uma difusão uniforme das frações através dos catalisadores. importante Brasil (POA estudo ZnOTiO2 ZnOTiO ZnO TiO2 TiO ZnO-TiO suportes placas 600 (60 8 µm. µm . µm) solar (HA FAH. (FAH) 62 49 4 9 4,9 16 42 2 4,2% respectivamente R 0974 0 974 0,974 296 96 2,9 103 1 03 1,0 10 3 10− min1 min min−1 096 0,9 099 99 0,99 repetidas catalisadores 60 (6 (FAH 6 4, 4,2 097 97 0,97 29 2, 1, min− 09 0, (

ABSTRACT The performance of aerobic granular sludge (AGS) process was evaluated for real leachate treatment, assessing the system capacity to form granules, biomass characteristics, and other engineering and microbiological aspects. Two sequencing batch reactors were operated with a leachate concentration of 25% (R1) and 50% (R2), with an 8-h cycle. The time required for granulation was greater than 80 days in both reactors, and solids loss was significant. The sedimentation rate was also outside the typical values for AGS reactors, with a sludge volumetric index in 30 min (SVI30) greater than 70 mL/g. Although the granules produced in R2 were more compact (200 μm), they were more resistant. Proteobacteria and Rhodobacteraceae were the phyla and the most abundant family in R2. The phylum Planctomycetota and the family Pirellulaceae were the most abundant in R1. Settling time reduction, feeding phase increase, and increased dissolved oxygen (DO) levels were fundamental strategies to improve reactors’ performance and stability. (AGS treatment characteristics aspects 25 R1 R (R1 50 R2, , (R2) 8h h 8 cycle significant 3 SVI30 SVI (SVI30 7 mLg mL g mL/g 200 (20 μm, μm μm) resistant reduction increase DO (DO stability 2 (R 5 (R2 SVI3 (SVI3 20 (2 (SVI (

RESUMO O desempenho do processo de lodo granular aeróbio (LGA) foi avaliado no tratamento de lixiviado real, considerando a capacidade do sistema de formar grânulos, as características da biomassa e outros aspectos de engenharia e microbiológicos. Dois reatores em bateladas sequenciais (RBS) foram operados com concentração de lixiviado de 25% (R1) e 50% (R2), com ciclos de 8 horas. O tempo necessário para a granulação foi superior a 80 dias em ambos os reatores, e a perda de sólidos foi significativa. A velocidade de sedimentação também ultrapassou os valores típicos para reatores LGA, com o índice volumétrico de lodo em 30 minutos (SVI30) superior a 70 mL/g. Embora os grânulos produzidos no R2 fossem mais compactos (200 μm), eles apresentaram maior resistência. Proteobacteria e Rhodobacteraceae foram o filo e a família mais abundantes em R2, enquanto o filo Planctomycetota e a família Pirellulaceae foram os mais abundantes em R1. A redução do tempo de sedimentação, o aumento da fase de alimentação e o incremento dos níveis de oxigênio dissolvido (OD) foram estratégias fundamentais para a melhoria do desempenho e da estabilidade dos reatores. LGA (LGA real microbiológicos RBS (RBS 25 R1 R (R1 50 , (R2) horas significativa 3 SVI30 SVI (SVI30 7 mLg mL g mL/g 200 (20 μm, μm μm) resistência OD (OD 2 (R 5 (R2 SVI3 (SVI3 20 (2 (SVI (

Resumen: La mejora de la simbiosis generada por hongos micorrízicos arbusculares (HMA) contra microorganismos patógenos han sido descritos, sin embargo el efecto de los HMA en cultivos de cacahuate es de interés por el valor de la cadena productiva que no ha sido atendida en su totalidad, por lo que el presente trabajo de investigación evaluó seis tratamientos: (T1) Plantas testigo sin HMA, (T2) Plantas con lixiviado de lombricomposta, (T3) Plantas inoculadas con micorrizas comerciales, (T4) Plantas inoculadas con micorrizas nativas, (T5) Plantas inoculadas con micorrizas comerciales + lixiviado y (T6) Plantas inoculadas con micorrizas comerciales + micorrizas nativas; en este sentido, se aislaron los hongos micorrízicos, identificándose Rhizoglomus clarum, Acaulospora alpina y Acaulospora aff. bireticulata, e inoculados en plantas de cacahuate en una superficie de 144 m2 a cielo abierto, de manera que, para corroborar la incidencia de los tratamientos evaluados, variables agronómicas como la altura, ancho de biomasa, daño foliar por Cercospora personata, número de flores, fueron evaluadas durante la precosecha cada 15 días y las variables postcosecha fueron; índice de área foliar, longitud de raíces, rendimiento de frutos y lípidos, así como el perfil de ácidos grasos presentes en el fruto. Finalmente, se evaluó la calidad del cacahuate según el CODEX STAN 200-1995, demostrando que el mejor tratamiento fue lixiviado + micorriza comercial, reportando rendimientos de 65.05% de frutos y 58% de lípidos totales, en su mayoría de ácidos grasos monoinsaturados (52% ácido oleico) seguido de poliinsaturados (21% ácido linoleico), finalmente de acuerdo al CODEX STAN 200-199 los cacahuates obtenidos corresponden a la calidad básica con dimensiones de 4 a 4.5 cm de ancho y largo respectivamente, estos cacahuates no pueden ser exportados pero si pueden ser comercializados en el país con destino a la transformación agroindustrial, permitiendo mejorar prácticas agrícolas al reducir el uso de agroquímicos.

Summary: The improvement of the symbiosis generated by arbuscular mycorrhizal fungi (AMF) against pathogenic microorganisms has been described, however, the effect of AMF in peanut crops is of interest due to the value of the productive chain that has not been fully attended. Therefore, this research work evaluated six treatments: (T1) Control plants without AMF, (T2) Plants with vermicompost leachate, (T3) Plants inoculated with commercial mycorrhizae, (T4) Plants inoculated with native mycorrhizae, (T5) Plants inoculated with commercial mycorrhizae + leachate and (T6) Plants inoculated with commercial mycorrhizae + native mycorrhizae; in this sense, mycorrhizal fungi were isolated, identifying Rhizoglomus clarum, Acaulospora alpina and Acaulospora aff. bireticulata, and inoculated in peanut plants in an area of 144 m2 in the open, so that, to corroborate the incidence of the treatments evaluated, agronomic variables such as height, width of biomass, foliar damage by Cercospora personata, number of flowers, were evaluated during the pre-harvest every 15 days and the post-harvest variables were; leaf area index, root length, fruit and lipid yield, as well as the profile of fatty acids present in the fruit. Finally, peanut quality was evaluated according to CODEX STAN 200-1995, showing that the best treatment was leaching + commercial mycorrhizae, reporting yields of 65.05% of fruits and 58% of total lipids, mostly monounsaturated fatty acids (52 % oleic acid) followed by polyunsaturated (21% linoleic acid), finally according to CODEX STAN 200-199 the peanuts obtained correspond to the basic quality with dimensions of 4 to 4.5 cm wide and long respectively, these peanuts cannot be exported but they can be marketed in the country for agro-industrial transformation, allowing improved agricultural practices by reducing the use of agrochemicals.

Resumen Los lixiviados de rellenos sanitarios son efluentes generados por la degradación de los residuos sólidos y la percolación del agua lluvia, caracterizados por ser un líquido de color oscuro con compuestos tóxicos, peligrosos, patogénicos, entre otras, que al ser descontaminados mediante procesos de oxidación avanzada acoplados a tratamientos biológicos logran efluentes con baja peligrosidad. A pesar de los beneficios otorgados por estas combinaciones, los investigadores usualmente se enfocan en analizar solo el efluente resultante, ignorando el impacto ambiental generado en la construcción, puesta en marcha y mantenimiento de los tratamientos, existiendo una brecha de conocimiento al no encontrarse suficiente bibliografía de trabajos que combinen el Scoping y la metodología de Conesa sobre tratamientos acoplados para la descontaminación de lixiviados, en la cuantificación del impacto ambiental. Atendiendo a lo mencionado, el presente manuscrito determinó los impactos sobre los componente biótico, abiótico y socioeconómico que genera acoplar un sistema fotocatalítico con un proceso biológico, para lo que se utilizó la técnica del Scoping como insumo de la cuantificación del impacto ambiental realizada a través de la metodología de Conesa, obteniendo como conclusión que impactos generados por fugas de lixiviado, así como los generados por los residuos y consumo de energía son considerados como críticos en los tratamientos y futuros investigadores que trabajen en el tema deben controlar, prevenir o mitigar. Finalmente, se destaca la presencia de impactos positivos de los tratamientos tales como el aumento de la disponibilidad del recurso hídrico gracias a la efectividad del tratamiento realizado y el cumplimiento de los Objetivos de Desarrollo Sostenible.

Abstract Landfill leachate is an effluent generated by the degradation of solid waste and the percolation of rainwater, which carries organic and inorganic substances, it is characterized as a dark-colored liquid with toxic, dangerous, pathogenic, and other compounds. It has been shown that the use of advanced oxidation processes coupled with biological treatments achieves effluents with low hazards. Despite benefits generate by these combinations, usually, the researcher’s goals focus just on the effluent, skipping the environmental impact generated in the construction, start-up, and maintenance of the treatments, resulting in a knowledge gap because there is not enough bibliography of works that develop combination between Scoping and Conesa methodology over coupled treatments used in leachate decontamination, in the environmental impact quantification. Considering the last, in the current manuscript was determined the impacts on the biotic, abiotic, and socioeconomic components, generated for coupling a photocatalytic system with a biological process. The Scoping technique was used as input of the environmental impact quantification through Conesa’s methodology. The main result was that environmental impacts produced by leachate leaks, waste generated, and energy consumed are considered as critical in the treatments, and futures researchers working in this field should control, prevent, or mitigate. Finally, the presence of positive impacts of the treatments such as the increase in the availability of water resources due to the effectiveness of the treatment carried out, and compliance with the Sustainable Development Goals is highlighted.

Resumen Introducción. El maíz (Zea mays L.) es un cereal de alto consumo en el mundo, este precisa una adecuada fertilización para cubrir sus requerimientos nutricionales. El Quitomax® es un bioestimulante que se ha empleado con éxito en la estimulación del rendimiento de diferentes cultivos. Objetivo. Evaluar la efectividad de la aplicación de Quitomax® en el crecimiento del cultivo del maíz de la variedad Francisco mejorado. Materiales y métodos. El estudio se realizó en áreas experimentales del Instituto Nacional de Ciencias Agrícolas, durante 2018 y 2019, sobre un suelo Ferralítico Rojo Lixiviado típico, eútrico, con un diseño experimental de bloques al azar con siete tratamientos y cuatro réplicas. Los tratamientos de Quitomax® aplicados fueron: imbibición de las semillas durante una hora en las concentraciones de 0, 5 y 1 g L-1, aspersión foliar a las concentraciones de 0, 5 y 1 g L-1, la combinación de ambas formas de aplicación y concentraciones y un testigo. Se evaluó el rendimiento y algunos de sus componentes. Resultados. Los mejores resultados se obtuvieron en el tratamiento que combinó imbibición de la semilla y aspersión foliar (1 g L-1) (T6) de Quitomax®, con un rendimiento de 12 t ha-1, atlura de la planta (A.P) de 2,12 m, diámetro medio de la mazorca (DMM) y del tallo (D.T) de 50,74 mm y 30,62 mm, respectivamente, altura de la mazorca superior (AMS) de 1,13 cm, número de granos por hilera (NGH) y por mazorca (NGM) de 32,27 y 455,33, respectivamente, 17,53 cm de longitud de mazorca (LM), masa de cien granos (M100S) de 38,90 g y 175,46 g de masa total de los granos (MTSM). Este tratamiento mejoró la relación beneficio/costo y mostró mayores ganancias, aunque fue el más costoso. Conclusiones. La aplicación a las semillas y foliar de Quitomax® fue efectiva al aumentar y rendimiento y sus componentes en el cultivo de maíz.

Abstract Introduction. Corn (Zea mays L.) is a highly-consumed cereal in the world, which requires adequate fertilization to cover its nutritional requirements. Quitomax® is a biostimulant that has been successfully used to stimulate the yield of different crops. Objective. To evaluate the effectiveness of the application of Quitomax® on the growth of the improved Francisco variety corn crop. Materials and methods. The study was carried out in experimental areas of the National Institute of Agricultural Sciences (INCA) during 2018 and 2019, on a typical Ferralitic Red Leached eutric soil, with a randomized block experimental design with seven treatments and four replications. The Quitomax® treatments applied were: imbibition of the seeds for one hour at the concentrations of 0, 5 and 1 g L-1, foliar spray at the concentrations of 0, 5 and 1 g L-1, combination of both forms of application and concentrations, and a control. Yield and some of its components were evaluated. Results. The best results were obtained in the treatment that combined seed imbibition and foliar spraying (1 g L-1) (T6) of Quitomax®, with a yield of 12 t ha-1, plant height (A.P) of 2.12 m, mean diameter of the ear (DMM), and diameter of the stem (D. T) of 50.74 mm and 30.62 mm, respectively, height of the upper ear (AMS) of 1.13 cm, number of grains per row (NGH) and per ear (NGM) of 32.27 and 455.33, respectively, 17.53 cm ear length (LM), one hundred grain mass (M100S) of 38.90 g and 175.46 g total grain mass (MTSM). This treatment improved the benefit/cost ratio, and showed higher profits, although it was the most expensive. Conclusions. Seed and foliar application of Quitomax® was effective in increasing the yield and its components in corn.

Resumen: El riego con lixiviados ofrece la oportunidad de cerrar el ciclo de nutrientes y producir un efluente de calidad adecuada para su vertido. La fitodepuración ha sido identificada como solución tecnológica efectiva, con bajos costos de implementación, fácil operación y mantenimiento disponible para la remoción de contaminantes de suelos y aguas contaminadas. En este marco, se realizó una investigación a escala laboratorio en la Universidad Católica Boliviana Sede Tarija. El objetivo de la investigación: verificar la fitodepuración del lixiviado del vertedero Municipal Pampa Galana ciudad de Tarija, utilizando tres especies ornamentales: Canna Indica, Zantedeschia Aethiopica, Pseudosasa Japonica. La fitodepuración de lixiviados se ha realizado en macetas individuales de aproximadamente 20 litros, con flujo vertical sub-superficial, donde se plantaron las especies ornamentales en un espacio abierto; las macetas se llenaron con sustratos: 1/3 de grava y 2/3 de suelo proveniente del mismo vertedero. Durante la experimentación los prototipos fueron alimentados considerándose una dilución media del 10%, donde se ha evaluado la eficiencia de eliminación de nutrientes: Nitrógeno y Fosfatos, y Demanda Química de Oxigeno (DQO). De los resultados, la especie Canna Indica mostró mejores rendimientos, obteniendo altos porcentajes de remoción: DQO (n hasta 80%), fosfatos (n>70%) y nitrógeno (n>98%). En términos generales, los resultados de todas las especies confirman la viabilidad del uso de diferentes especies en la fitodepuración de lixiviados de rellenos sanitarios. El riego con lixiviados diluidos tampoco afectó al crecimiento de las especies; las plantas regadas con el lixiviado diluido desarrollaron mayor biomasa que las plantas de control.

Abtract: Leachate irrigation offers the opportunity to close the nutrient cycle and produce an effluent of suitable quality for discharge. Phytodepuration has been identified as an effective technological solution, with low implementation costs, easy operation and available maintenance for the removal of pollutants from contaminated soils and water. Within this framework, laboratory-scale research was carried out at the Bolivian Catholic University, Tarija Campus. The objective of the research: to verify the phytodepuration of leachate from the Pampa Galana Municipal Landfill in the city of Tarija, using three ornamental species: Canna Indica, Zantedeschia Aethiopica, and Pseudosasa Japonica. The phytodepuration of leachates was carried out in individual pots of approximately 20 liters, with vertical subsurface flow, where the ornamental species were planted in an open space; the pots were filled with substrates: 1/3 gravel and 2/3 soil from the same landfill. During the experimentation, the prototypes were fed considering an average dilution of 10%, where the efficiency of nutrient elimination was evaluated: Nitrogen and Phosphorus, and Chemical Oxygen Demand (COD). From the results, the Canna Indica species showed better performances, obtaining high removal percentages: COD (n up to 80%), phosphates (n>70%) and nitrogen (n>98%). In general terms, the results for all species confirm the feasibility of using different species in the phytodepuration of landfill leachate. Irrigation with diluted leachate also did not affect species growth; plants irrigated with diluted leachate developed higher biomass than control plants.

RESUMO A composição do lixiviado de aterros sanitários sofre influência de diversos fatores, entre eles as condições climáticas. Assim, o objetivo deste estudo consistiu em analisar a variação sazonal na composição e na toxicidade do lixiviado gerado no aterro sanitário localizado em Campina Grande (PB), região semiárida do Brasil, o qual apresentava idade inferior a cinco anos (aterro jovem). A amostragem foi constituída de sete coletas de lixiviado e passou por caracterização físico-química e análises fitotoxicológicas em sementes de tomate (Solanum lycopersicum) e repolho (Brassica oleracea). Na avaliação fitotoxicológica, foram analisados os indicadores crescimento relativo da raiz (CRR) e inibição do crescimento da raiz (ICR), expostos a três tratamentos, cujas concentrações foram de 1, 5 e 10% de lixiviado. Para avaliar a relação da precipitação com a composição e a toxicidade do lixiviado, foi utilizada a análise de correlação entre as variáveis estudadas. De acordo com os resultados, verificou-se que a precipitação influenciou na redução do pH, no entanto, para os demais indicadores físico-químicos (alcalinidade total, nitrogênio amoniacal total, cloretos, demanda química de oxigênio e sólidos voláteis) e para os indicadores fitotoxicológicos (CRR e ICR), não foram obtidas relações com a precipitação. Logo, os eventos de chuva determinados neste estudo não causaram alterações na composição nem na toxicidade do lixiviado.

Abstract The composition of the leached in sanitary landfills is influenced for several factors, including climatic conditions. In this study aimed to analyze the seasonal variation in the composition and toxicity of the leached generated in the Sanitary Landfill located in Campina Grande, semiarid region of Brazil, which was less than 5 years old (young landfill). Sampling consisted of 7 leached collections, in which physicochemical characterization and phytotoxicological analyzes were carried out in tomato (Solanum lycopersicum) and cabbage (Brassica oleraceae) seeds. In the phytotoxicological assessment, the indicators Relative Root Growth (RRG) and Inhibition of Root Growth (IRG) were analyzed, exposed to three treatments (T1, T5 and T10), in the concentrations from 1%, 5% and 10% of leached. To assess the relationship from precipitation with composition and toxicity of the leached, correlation analysis was used between the variables studied. According to the results, the precipitation influenced the pH reduction, however, for the other physical-chemical indicators (total alkalinity, total ammoniacal nitrogen, chlorides, chemical oxygen demand and volatile solids) and for the phytotoxicological indicators (CRR and ICR ), relationships with precipitation were not obtained. Therefore, the rainfall events determined in this study did not cause changes in the composition and toxicity of the leached.

RESUMO Reclaimed Asphalt Pavement (RAP) has a variety of organic and inorganic compounds that can interact with the environment and promote deleterious effects on human health. This study investigated the potential toxicity of RAP through metal determination, polycyclic aromatic hydrocarbon (PAH) analysis and acute toxicity tests with Daphnia magna. Leached and solubilized extracts of RAP samples and a freshly produced asphalt sample were compared. Regarding metals, Mn was above the Brazilian acceptance criteria in the solubilized extract. The samples showed concentrations of Cd, Cr, and Pb, which are on the list of substances that render waste hazardous. For PAH, two samples of leachate had BaP concentration above the maximum value allowed and the other samples had BaP values close to the established limit. In addition, the samples still presented concentrations of BaA, BbF, IcdP, and Chr. For the acute toxicity tests, two solubilized samples indicated acute toxicity to Daphnia magna. The results indicated that the method of preparing the leached and the solubilized extract influenced the values of metals and acute toxicity. Two samples of RAP could be classified as hazardous waste, pointing out that these materials have the potential to leach hazardous substances to the environment. Therefore, the disposal of this type of waste should be carefully evaluated, as its composition contains substances that may degrade the environment and cause toxicological effects on living organisms.

ABSTRACT Pavimentos asfálticos fresados (PAF) apresentam uma variedade de compostos orgânicos e inorgânicos que podem interagir com o meio ambiente e promover efeitos deletérios à saúde humana. Este estudo investigou o potencial de toxicidade dos PAF por meio da determinação de metais, hidrocarbonetos policíclicos aromáticos (HPA) e testes de toxicidade aguda com Daphnia magna. Foram comparados extratos lixiviados e solubilizados de amostras de PAF e de resíduo asfáltico fresco. As análises de Mn apresentaram concentrações acima do critério de aceitação normativo brasileiro para os extratos solubilizados. As amostras resultaram em concentrações de Cd, Cr e Pb, que estão na lista de substâncias que conferem periculosidade aos resíduos. Em relação aos HPA, duas amostras de lixiviado apresentaram concentração de BaP acima do valor máximo permitido e as demais amostras apresentaram valores de BaP próximos ao limite estabelecido. Ademais, foram identificadas nas amostras concentrações de BaA, BbF, IcdP e Chr. Para os ensaios de toxicidade aguda, duas amostras solubilizadas indicaram toxicidade aguda para Daphnia magna. Os resultados indicaram que o método de preparo dos lixiviados e do extrato solubilizado influenciaram os valores de metais e a toxicidade aguda. Duas amostras de PAF foram classificadas como resíduos perigosos, sinalizando que tais materiais apresentam potencial para lixiviar substâncias perigosas ao ambiente. Portanto, a disposição em solo desse tipo de resíduo deve ser criteriosa, uma vez que sua composição contém substâncias que podem impactar o meio ambiente e causar efeitos toxicológicos em organismos vivos.

Resumen Uno de los principales problemas en México es la contaminación por lixiviados que se producen en los sitios de disposición final de residuos ya que son altamente tóxicos y dañan a la biota. Esta investigación se centra en determinar las características del lixiviado producido en el sitio de disposición final no controlado del municipio de Tlapacoyan, Veracruz (México). Como resultado, se determinó que los parámetros que producen daño a la biota son nitrógeno total (152.759 mg L-1), mercurio (0.006 mg L-1), cadmio (0.003 mg L-1), cobre (0.052 mg L-1), cromo (0.0731 mg L-1), níquel (0.0524 mg L-1), plomo (0.005 mg L-1) y coliformes totales (>2 400 NMP), al no cumplir al menos una de las normas nacionales e internacionales de límites máximos permisibles. Asimismo, se determinó que el lixiviado producido en este sitio es del tipo maduro y poco biodegradable (DBO/DQO=0.018), por lo que los métodos típicos o de biorremediación no son recomendables para su tratamiento.

Abstract One of the main problems in Mexico is contamination by leachates that are produced in final waste disposal sites, since they are highly toxic and damage the biota. This research focuses on determining the characteristics of the leachate produced in the uncontrolled final disposal site in the municipality of Tlapacoyan, Veracruz (Mexico). As a result, it was determined that the parameters that cause damage to the biota are total nitrogen (152.759 mg L-1), mercury (0.006 mg L-1), cadmium (0.003 mg L-1), copper (0.052 mg L-1), chromium (0.0731 mg L-1), nickel (0.0524 mg L-1), lead (0.005 mg L-1) and total coliforms (> 2 400 MPN), as they do not meet at least one of the national and international standards of maximum permissible limits. Likewise, it was determined that the leachate produced at this site is of the mature and poorly biodegradable type (BOD/COD=0.018), so that the typical or bioremediation methods are not recommended for its treatment.

Resumen La minería de metales en Costa Rica, y el uso de sustancias tóxicas en esta actividad, ocasionalmente ha resultado en el abandono negligente de estructuras de desechos que contienen cantidades significativas de metales tóxicos. Estas estructuras que han quedado expuestas a la oxidación y a la meteorización resultan en la liberación ambiental de metales, lo cual propicia la afectación en la calidad natural de los cuerpos de agua superficiales circundantes. El objetivo de la investigación fue determinar que los pasivos mineros abandonados en el Líbano de Tilarán, Guanacaste, son una fuente potencial de contaminación por metales para las aguas, sedimentos y macroinvertebrados bentónicos de los ríos San José y Cañas. Las posibles consecuencias para el medio ambiente asociadas con la presencia de desechos mineros se evaluaron cuantitativa y cualitativamente a través de las cantidades de metales presentes en los desechos y lixiviados. Se realizaron pruebas de infiltración y una prueba cinética de celda húmeda permitió describir los procesos y las reacciones químicas que pueden ocurrir en los desechos mineros durante la lluvia, asociados con la carga de metales en el lixiviado. La presencia de pirita (FeS2) favorece la acidificación del medio y la liberación de metales, se destaca mediante pruebas de difracción de rayos X en muestras de los materiales de desecho. Los resultados muestran un alto contenido de metales (37.8 toneladas de plomo, 20.2 toneladas de arsénico y 0.4 toneladas de cadmio) del total de ~ 106 toneladas en pasivos mineros, la solubilización de estos y otros metales en un medio ácido oxidante (pH: 4.16, CE: 3620 µs / cm y ORP: 275 mV) durante la transición de la estación seca y lluviosa y una carga importante de metales (277 kg / mes de zinc, 234 kg / mes de magnesio, 165 kg / mes de aluminio, 96.1 kg / mes de hierro, 2.68 kg / mes de cadmio, 0.90 kg / mes de arsénico y 0.22 kg / mes de plomo) en lixiviados que llegan al río San José en septiembre. Esta investigación mostró que los pasivos mineros abandonados en el Líbano son una fuente potencial de contaminación por metales para los ecosistemas de agua dulce circundantes.

Abstract Metal mining in Costa Rica, and use of toxic substances in this activity, has occasionally resulted in the negligent abandonment of waste structures containing significant amounts of toxic metals. These structures have been exposed to oxidation and weathering, resulting in the environmental release of metals, thus affecting the quality of the surrounding freshwater ecosystems. The objective of the investigation was to determine to what extent the abandoned mining liabilities in Líbano de Tilarán, Guanacaste, are a potential source of metal contamination for the waters, sediments and benthic macroinvertebrates of the San José and Cañas Rivers. The possible consequences for the environment associated with the presence of mining wastes were quantitatively and qualitatively assessed through the amounts of metals present in the wastes and leachate. Infiltration tests were carried out and a wet cell kinetic test allowed describing the processes and chemical reactions that are likely to occur in mining wastes during rain, associated with the loading of metals in leachate. The presence of pyrite (FeS2), which favors the acidification of the medium and the release of metals, was shown by X-ray diffraction tests on samples of the waste materials. The results show a high content of metals (37.8 tons of lead, 20.2 tons of arsenic and 0.4 tons of cadmium) from the total of ~106 tons in mining liabilities, the solubilization of these and other metals in an oxidizing acid medium (pH: 4.16, EC: 3620 µs / cm and ORP: 275 mV) during the dry-rainy season transition and an important load of metals (277 kg / month of zinc, 234 kg / month of magnesium, 165 kg / month of aluminum, 96.1 kg / month of iron, 2.68 kg / month of cadmium, 0.90 kg / month of arsenic and 0.22 kg / month of lead) in leachates arriving to the San José River in September. This investigation showed that the abandoned mining liabilities in Líbano are a potential source of metal contamination for the surrounding freshwater ecosystems.