The deposition of volcanic ash in areas affected by erupting volcanoes can contaminate the soil with heavy metals, thereby jeopardizing food security and public health. This study focused on the use of compost for the bioremediation of this type of contaminated soil and on evaluating the effectiveness of this remediation technique in a horticultural crop. To this end, composts made from organic waste generated in the areas with volcanic-ash-affected soil, such as crop residues, cow manure, and cheese whey, were used. The design and optimization of the composting process for these wastes were described using three piles with the same proportion of crop residues and cow manure but different doses of whey (pile 1: without whey, pile 2: whey diluted with water (1:2 (v:v)); and pile 3: with undiluted whey) and by monitoring the evolution of physicochemical and biological parameters throughout the compositing process. The effectiveness of the composts obtained for soil remediation was evaluated by assessing the physiological response of a lettuce crop in pots. Five treatments were used: control soil without fertilization, inorganic fertilization, and the three composts obtained. The main agronomic properties of the soil and heavy metal availability were measured, along with the physiological and chemical parameters of the lettuce, including growth and macronutrient and heavy metal content. The results obtained in the composting experiment showed that the addition of cheese whey only affected the rate of organic matter degradation and the salt content of the final composts, without negatively affecting the stability and humification of their organic matter or their plant nutrient content. In the pot experiment, all composts improved soil fertility and reduced the availability of Ni, As, Cd, and Pb, but this did not consistently reduce uptake into lettuce, except in the case of Pb. Therefore, it is advisable to adjust the compost application rate and optimize crop selection to minimize the impact of heavy metals on the food chain, thereby ensuring safe production.

The expansion of climate monitoring networks has generated an increasing accumulation of end-of-life meteorological sensors, creating a specialized stream of waste electrical and electronic equipment (WEEE) that remains largely unaddressed in developing countries. This study presents a material characterization and sustainable management framework for obsolete meteorological sensors installed in automatic weather stations in Ecuador. A hybrid methodological approach was applied, combining field inventory of 16 stations, gravimetric measurements, and analysis of manufacturer technical specifications to estimate material composition and recovery potential. Results show that 65–90% of the total sensor mass consists of recyclable materials, including aluminum, stainless steel, copper, glass, and engineering polymers. A smaller fraction contains components requiring controlled management due to the potential presence of hazardous additives, such as PVC (polyvinyl chloride) elements and electronic microdevices. Based on these findings, a multi-phase management protocol is proposed, incorporating selective disassembly, material segregation, traceability mechanisms, and processing under extended producer responsibility principles. The framework supports circular economy strategies and offers a replicable model for improving sustainability in climate monitoring infrastructure and specialized WEEE management in low- and middle-income countries.

Potato (Solanum tuberosum L.) production on volcanic soils takes place in complex agricultural systems where natural soil properties and agricultural practices coexist and may be associated with trace element dynamics. This study evaluated the concentration and apparent transfer index of Pb, Cd, Hg, As, and Ni in the soil-potato system of Quero Canton, Tungurahua, Ecuador. Soil and whole-plant samples were collected from 20 georeferenced sites and analyzed using standardized methods and atomic absorption spectrophotometry. Soil chemical composition varied among sites and was characterized by elevated phosphorus and potassium contents. Pb and As concentrations in soil remained below guideline values for agricultural soils, whereas localized high concentrations of Cd, Hg, and Ni were observed. Mean concentrations in plant tissues were 0.28 mg/kg for Hg, 0.38 mg/kg for As, and 1.13 mg/kg for Ni, all of which were below reported phytotoxicity thresholds. Bioconcentration factors indicated generally limited soil-to-plant transfer. Hg showed the highest variability in BCF values. Principal component analysis showed that variation in the apparent transfer index was associated with pH, bulk density, and electrical conductivity. These findings highlight the importance of soil quality monitoring to support the management of potato production systems on volcanic soils.

Heavy metal contamination of soil and groundwater is one of the most significant global issues affecting food security and food safety. Alarming statistics report high levels of soil contamination worldwide and several studies have documented the mechanisms by which plants bioaccumulate heavy metals. This bibliometric research study is the first step toward summarising the existing scientific literature and suggesting next steps for evaluating advances in modelling the transport of heavy metals in agricultural soils and their leaching into groundwater. Several numerical models have validated the phenomenon. For example, the multiple linear regression (MLR) model is effective in predicting mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), zinc (Zn) and nickel (Ni), but not copper (Cu) and chromium (Cr). In comparison, the models constructed by Random Forest (RF) and Gradient Boosted Machine (GBM) were able to predict the bioaccumulation factors of Zn, Cu, Ni, Cr, Hg and Cd well. Furthermore, most studies report high heavy metal concentrations in the study areas, exceeding international standards several times, indicating the absence of public control policies. This review highlights that future studies must address several persistent limitations; for example, many authors suggest using bioavailable heavy metal content instead of total content. However, the authors of this review believe that this report provides new insights for policymaking related to heavy metal pollution in soil-crop ecosystems and food security.

El libro "Centro de bioconocimiento: ciencia, territorio y saber ancestral para el fortalecimiento de la agricultura andina” es una obra que integra, con visión técnica y cultural, los fundamentos del bioconocimiento como eje para revitalizar la agricultura familiar campesina en los Andes del norte del Ecuador. A partir del trabajo del Centro Experimental San Francisco de la Universidad Politécnica Estatal del Carchi, esta obra articula ciencia aplicada, prácticas agroecológicas y saberes ancestrales del pueblo Pasto para fortalecer sistemas agrícolas resilientes, sostenibles y con identidad territorial. A lo largo de sus capítulos, el libro aborda la cosmovisión andina, la biodiversidad agrícola del Carchi, la caracterización ecológica de los Andes, técnicas de producción sostenible, así como una amplia sistematización de cultivos emblemáticos: gramíneas, hortalizas, tubérculos, frutales, medicinales y ornamentales, acompañada de fichas técnicas y prácticas locales. La obra incorpora, además, estudios de caso comunitarios, el calendario agrícola andino, y enfoques para la comercialización agroecológica en circuitos cortos. Con rigor científico y profundo respeto por la cultura andina, esta publicación se convierte en una herramienta indispensable para técnicos, agricultores, estudiantes, docentes e instituciones que buscan fortalecer modelos agroecológicos basados en la biodiversidad, el conocimiento ancestral y la sostenibilidad. Una invitación a comprender el territorio, recuperar la memoria agrícola y construir una agricultura que valore tanto la ciencia como la herencia viva de los pueblos andinos.

Precipitation variability in the tropical Andes is strongly influenced by complex topography and regional hydroclimatic processes, yet the spatial organization and temporal evolution of precipitation regimes remain insufficiently characterized. This study identifies dominant precipitation regimes in the Upper Pastaza River Basin, Ecuador, and examines their variability during 1981–2025 using daily precipitation data from the Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS) dataset. CHIRPS estimates were evaluated against observations from three meteorological stations, revealing spatial differences in precipitation estimation accuracy and a general underestimation of monthly precipitation totals. Empirical Orthogonal Function (EOF) analysis and K-means clustering were applied to identify four recurrent precipitation Weather Types (WTs), ranging from a dominant low-intensity regime (WT1), representing approximately 70% of classified days, to a relatively infrequent but intense precipitation regime (WT2), accounting for approximately 1.7%. Seasonal and interannual variability was characterized through regime occurrence frequencies and temporal recurrence patterns. Monotonic trends were assessed using Kendall’s rank correlation coefficient and Sen’s slope estimator, while the burstiness index was used to examine temporal irregularity. A statistically significant positive trend was identified in WT2 occurrence (Kendall’s τ = 0.3830, p = 0.0002), whereas no significant trends were detected for the remaining regimes. Comparison with the recent period (2015–2025), using a consistent classification framework, revealed differences in regime occurrence while preserving broadly similar spatial precipitation patterns. These findings highlight changes in the occurrence of specific precipitation states rather than a generalized redistribution of all regimes, providing insights into hydroclimatic variability across the Andes–Amazon transition zone.