The removal of heavy metals from wastewater is an environmental challenge which demands the use of environmentally friendly materials that promote a circular economy. This study aimed to apply a novel composite of an activated nanoclay/hydrocolloid in the removal of heavy metals from wastewater. A composite blended under pressure was prepared with spray-dried hydrocolloid derived from Nostoc sphaericum algae and activated nanoclay in an acid medium and 1M NaCl. The composite and components were analyzed through infrared (IR), X-ray (XR), ζ potential, cation exchange capacity (CEC), particle size, and SEM images. The composite was subjected to the adsorption of heavy metals (Pb, As, Zn, and Cd) at pH 4.5 and the removal percentage, kinetics, and adsorption isotherms were evaluated. It was observed that the activated nanoclay and the composite that presented a particle size of around 400 nm significantly increased (p-value < 0.05) the CEC, ζ potential, the functional groups, and chelating components, removing heavy metals above 99% for Pb, As 33%, Cd 15%, and Zn 10%. Adsorption kinetics was adjusted to the pseudo second-order model (R² > 0.98), and the Langmuir and Freundlich models better represented the sorption isotherm at 20 °C. The formulated composite presents a good ability to remove heavy metals in wastewater.

The avocado fruit is an agro-industrial product with high export demand in Peru due to its sensory and nutritional qualities, which can be affected during storage. The study aimed to evaluate the effect of the application of a coating formulated with potato starch (Solanum tuberosum ssp andigena), nopal mucilage (Opuntia ficus indica), and pectin on the physicochemical and physiological properties during the storage of Fuerte and Hass avocados. Samples were taken in their harvest state from the plantation in “Occobamba”, which is cultivated by the Avocado Producers Association in Chincheros, Apurímac, Peru. Physicochemical properties (titratable acidity, pH, total soluble solids) and physiological properties (weight loss, firmness, and color L* a* b*) were determined during 20 days of storage at 20 °C. The elaborated films present high transparency and low a_w values. In the coated avocado of the Hass and Fuerte varieties, acidity and total soluble solids decreased significantly (p-value < 0.05) during the storage time. Weight loss and firmness of coated fruits decrease to a lesser extent. Luminosity L*, color index, and color variation showed better attributes for the coated samples. The use of coatings made with potato starch, nopal mucilage, and pectin allows the physicochemical and physiological properties of avocado fruits to be maintained for a longer time during storage.

Cultural customs often condition solid waste management, especially in developing countries. The decomposition of solid waste depends on climatic conditions and is related to geomorphology and anthropogenic practices. Leachate generated in landfills can migrate superficially and underground, contaminating soils and aquifers. Knowing the level of contaminant load in leachate is important for proper solid waste management. However, in the Andean regions of Peru, there is scarce data on the polluting potential of leachates. This research aimed to determine the Leachate Pollution Index (LPI) according to the sub-indexes of organic, inorganic, and heavy metals from landfills in the high Andean regions of Peru. Physical, chemical, and microbiological parameters were evaluated in fresh and retained leachate samples, in both dry and rainy seasons, from two landfills located at around 3000 m of altitude. The results showed high contamination levels, particularly in BOD₅, COD, NH₃-N, and total coliforms, with high organic and inorganic sub-indexes that affect the LPI, indicating high levels of contamination and posing a potential risk to surrounding ecosystems. It was also found that the high Andean landfills studied have a good-to-high biodegradability. This research contributes essential baseline information for environmental monitoring and supports the need for improved leachate management in high-altitude landfills in Peru and similar Andean contexts.

Lentic ecosystems are highly vulnerable to anthropogenic disturbances, which can lead to ecological imbalances with the loss of native biodiversity. This research evaluated the impact of anthropogenic activities on water quality and the trophic status of the Pacucha Lagoon, Andahuaylas, Apurimac. Seasonal sampling was conducted at six strategic points on the surface and bottom of the lake, following standardized protocols, during both the dry and rainy seasons. Physical and chemical parameters, metal ions, chlorophyll-a, and trophic status were determined using the Carlson indices, and water quality was assessed through the WQI-PE. The quantification of anthropogenic impacts was performed using the Leopold matrix. Statistical analysis included descriptive methods, ANOVA, Pearson correlation, and PCA at 5% significance. The results classify the lake as having “Regular” water quality according to WQI-PE. Physical and chemical parameters remain within the Environmental Quality Standards (ECA-Peru), while heavy metal ions exceed the limits in both seasons. The system exhibits mesotrophic conditions that tend to become eutrophic during the rainy season, suggesting a favorable nutrient balance for biological productivity. Activities with the most significant adverse impacts include agricultural practices that involve the intensive use of agrochemicals, morphological alterations to the surrounding area, and unregulated aquaculture. The lack of effective regulatory mechanisms and a lack of commitment to conservation suggest a high risk of irreversible degradation of the Pacucha Lagoon ecosystem.

During its journey, the river water suffers natural or anthropic contamination, deteriorating its quality. This impact can be qualified by determining the pollution Indexes (IPO). The work aimed to evaluate the spatial and temporal variation of the IPOs in the water of the high Andean micro-basin of the Chumbao River. The study included the section from 13°46'38.4” S, 73°15'32.3” W at 4079 m of altitude up to 13°35'26.4” S, 73°27'00.8” W at 2572 m of altitude. Physical, chemical, and microbiological parameters of the water were determined in 8 points along the river. These were grouped to calculate the IPO by mineralization (IPOMI), organic matter (IPOMO), suspended solids (IPOSUS), and trophic (IPOTRO) in the dry and rainy seasons. The indexes were categorized from 0.0 (not polluted) to 1.0 (highly polluted). The data were collected in triplicate and valuated through ANOVA and Tukey's test. It was found that IPOSUS, IPOMI, and IPOMO. The points near the head of the micro-basin reported no and low pollution; besides, they increased considerably in urban areas reaching highly polluted levels. In contrast, IPOTRO reported a eutrophic state, and that contamination levels were higher in the dry season. The waters of the Chumbao River above 2900 m of altitude and close to the head of the micro-basin do not show contamination, but in the urban area the index of pollution is high.

Las estimaciones y uso de los registros meteorológicos que proporcionan los satélites facilitan la toma de decisiones técnicas. Por ello el objetivo fue analizar y comparar los datos de precipitación mensual entre satélite GPM IMERG_F v6 y del Servicio Nacional de Meteorología e Hidrología (SENAMHI). El método consistió evaluando los valores faltantes con el paquete “mice” y el software Hydraccess que determina el vector regional y vector correl, y para determinar los errores estadísticos se usó la librería hydroGOF. En resultados el control de calidad de ambos datos de precipitación mensual de factor D.E.D fue < 0,2 y Correl./Vector > 0,7 ajustándose dentro de los parámetros de evaluación, excepto la estación Iñapari con 0,657; comparando los mismos mostró que los errores estadísticos en el NSE fueron < 0,65 que no cuantifica adecuadamente el modelo, en cambio con los datos de CC > 0,8 muestra mejor concordancia. En el RMSE varía al promedio de 146,48 mm considerados como valores extremos, analizando el porcentaje las estaciones Iñapari, Puerto Maldonado, Cuyo Cuyo, Macusani y Ollachea de valores positivos ostentaron una sobreestimación del satélite, sin embargo, en las estaciones de San Gaban, Quincemil y Chontachaca se estima valores negativos y muestran una subestimación. Analizando el índice de detección PDO = 1 ETS = 0,2 FAR = 0,2 y FBI = 1,4 de la serie entre datos mostró una buena representación, excepto las estaciones Ollachea, Macusani y Chontachaca. Concluyendose que los datos del satélite GPM proporciona bajo porcentaje de valores cercanos a los reales del SENAMHI.