Water quality impacts on water bodies such as reservoirs are strongly influenced by the hydrodynamics of the system. Although multiple models might be applied, they are limited by the simplification of the variables. In this study, a two-dimensional public domain model, CE-QUAL-W2, was adapted to test whether it would generate an accurate hydrodynamic simulation of the URRÁ Reservoir in Córdoba, Colombia, to understand water quality. The variables to be modeled were temperature and dissolved oxygen due to their importance in ecological terms. Thus, trial and error techniques were used to calibrate and validate the model, varying different parameters such as the wind shelter coefficient (WSC). Although the model accurately predicted the hydrodynamic part by having daily flow information, significant modifications to the eddy diffusivity coefficient were required to simulate acceptable longitudinal currents. This research shows that the CE-QUAL-W2 model fits adequately to tropical lentic systems. However, it is recommended that, for future studies, the modeling be adjusted using hourly data, especially in areas where inflow and boundary conditions are unstable.

La calidad del aire en la región del Alto San Jorge está siendo afectada por la minería, cuyos impactos ambientales se asocian a afectaciones en la salud humana. El objetivo del estudio fue analizar la fragilidad ambiental de los ecosistemas para identificar y relacionar las afectaciones a la salud ambiental como consecuencia de la emisión de contaminantes atmosféricos. La metodología inició con la caracterización física y geoespacial del área y la atribución de pesos ponderados mediante el proceso analítico jerárquico. La suma ponderada de las capas de datos se realizó a través de Sistemas de Información Geográfica definiendo clases de fragilidad del ecosistema basados en Ross (1994). De esta manera, se determinó la amenaza y el riesgo por contaminación atmosférica para SO2, NO2, PM2,5 y PM10. Los resultados mostraron la existencia de riesgo de medio a alto y alto por SO2 en las zonas aledañas a los cascos urbanos. Para NO2, el riesgo fue homogéneo en un nivel intermedio para toda la zona. Para el material particulado (2,5 µm y 10 µm), de medio a alto y alto debido a la influencia de minería de ferroníquel y carbón. Este estudio denota la necesidad de aplicar oportunamente medidas de prevención, mitigación o control de este riesgo.

In this study, composting as an alternative approach for managing mercury-contaminated biomass in water bodies affected by gold mining in the Choco department was evaluated. A single-factor experiment with three treatments containing varying amounts of Eleocharis interstincta biomass sourced from mercury-contaminated sites was designed. During the composting process, physicochemical parameters were monitored such as temperature, pH, and electrical conductivity, while analyzing the behavior of mercury through mass balance assessments. Additionally, we determined the bioavailability of mercury in the final compost and characterized the physicochemical parameters of each compost sample. The mercury mass balance indicated a decrease in the total mercury content in the initial biomass over the composting period of 170 days. However, the total mercury concentration in the final compost increased due to the transformation and subsequent reduction of the original biomass. Mercury speciation analysis revealed that mercury was predominantly associated with the less bioavailable fractions (F4 and F5), suggesting its stabilization and low availability to biota. Therefore, the final compost has the potential to restore degraded soils by improving moisture retention, porosity, and soil fertility, thereby promoting plant growth. However, it does not fully meet the national and international technical standards for solid organic fertilizers or compost.

Integrated Water Resources Management (IWRM) is a central concept in water governance, promoting cooperation and articulation in fragmented systems. This study identifies and analyses tools used in water resources managing in Brazil, through a methodological proposal based on integrated management concepts. The research was carried out online using search keys and included academic works and institutional initiatives, both private and public. The study identified 60 tools and assessed their applicability, considering the relevant focus and context within different categories of IWRM. The majority of identified tools are technical ones and designed for water quality assessment and monitoring. A smaller number of tools were related to user registration, land use and occupation assessment, communication, and information dissemination. This study demonstrates the use of the water management tools and it provides an overview of the potential benefits associated with their application to improve local, regional, and national water governance.

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