The Sustainable Development Goals of the United Nations (SDGs) establish the need to guarantee quality water for all people. In numerous rural settlements of Colombia, access to clean drinking water is a formidable challenge as frequently observed when waterborne diseases arise, mainly in vulnerable populations without basic sanitation systems. The main objective of this study was to assess the quality and potential use of groundwater sampled from 17 monitored wells in a typical rural settlement in Colombia. Water quality was determined by applying a quality index and performing a principal component analysis (PCA) to determine the weights of each parameter. The results of the Phosphorus, Nitrates, Thermotolerant coliforms and pH variables exceeded regulatory limits, mainly in areas affected by anthropogenic sources with an insufficient sewage network. Coliform population and NO₃ exceeded World Health Organization recommended thresholds for drinking water. Therefore, the qualities of the studied water samples were unsuitable for human consumption without prior adequate treatment and, hence, one recommendation is to regulate groundwater monitoring quality. In addition, unhealthy waste disposal practices should be abolished, while permanently controlled modern techniques should be introduced.

The mayflies are insects widely known as indicators of aquatic quality in freshwater systems, they are abundant and diverse in tropical streams. In this study, it was determined the influence of physical, chemical and bacteriological characteristics on the Ephemeroptera assembly in a period of low precipitation in the Ocoa river of Meta department. There were 5,332 nymphs belonging to 4 families, 10 genera and 3 species. Three new genera records and one species are presented for Meta: Cloeodes, Zelusia, Lumahyphes and Americabaetis alphus. The genera Camelobaetidius and Varipes were found associated with conditions of contamination by organic matter and water mineralization. Likewise, Americabaetis, Thraulodes, Lumahyphes and Tricorythodes were associated with contamination conditions, especially with nitrites and nitrates. Nanomis, Cloeodes and Zelusia showed greater sensitivity to the contamination condition and were related to high percentages of dissolved oxygen in the water and they were in the sampling stations of the upper part in the river. It is important to mention that there were not Ephemeroptera in most of the stations associated with the urban area. That reflects their high sensitivity to polluting conditions at low precipitation period.

Rainwater harvesting is a popular artisanal method that provides substantial economic advantages and effectively addresses the issue of water scarcity in many parts of Colombia. This method may not be appropriate from a public health standpoint in every instance. Despite Colombia’s ample precipitation, ensuring a stable water supply is problematic, particularly due to the dramatic fluctuations in weather patterns, such as droughts and severe rainy seasons, which affect the dependability of the water delivery system. This study examines the urban region of Villavicencio with two main objectives: (I) to assess the physico-chemical and microbiological quality of rainwater in the municipality’s residential and commercial sectors; and (II) to analyze the spatial distribution of physico-chemical parameters within the study area. The quality and spatial distribution of rainwater resources in the urban catchment region of Villavicencio were evaluated through the analysis of data obtained from several sampling locations.

Agricultural soils may become polluted by heavy metals as a result of receiving a significant amount of pollutants from different sources of land applications, such as fertilizers, animal manure, sewage sludge, pesticides, and wastewater irrigation. Given that information on the distribution of heavy metals (HMs) in the Piedemonte Llanero of Colombia is still quite limited, the main objectives of this work were to characterize the content of these elements and their potential pollution level in acidic soils under different agricultural systems. The hypothesis is to verify if the type of land use poses an environmental threat. To achieve these goals, the concentrations of seven metals were determined in the soils of three agricultural production systems: oil palm, pastures, and semi-annual crops. Soil contamination was evaluated based on the Geo-Accumulation Index (I-geo), contamination factor (CF), Pollution Load Index (PLI), and Nemerov Integrated Pollution Index (NIPI). One outstanding result was that the average concentrations of HMs in the collected topsoil samples were as follows: Mn (110.5 mg kg-1), Zn (31.93 mg kg-1), Cr (8.85 mg kg-1), Ni (11.68 mg kg-1), Cu (11.28 mg kg-1), Pb (9.42 mg kg-1) and Cd (0.21 mg kg-1). The results obtained from this study provide an estimation of the pollution status of HMs. Agricultural activities, especially the overuse of phosphate fertilizer, were the main source of nutrients across the study area. This information can become a fundamental tool to establish monitoring and follow-up processes for sustainable soil management in the Piedemonte Llanero. In conclusion, the present study highlights and provides specific information in a hyperhumid environment.

Surface water resources have played a fundamental role in the development of human societies. Considering that different agricultural and industrial activities are carried out in the Acacias River basin, the main objective of this research was to analyze the influence of land use on the water quality in this area by identifying the main sources that influence river water quality. The methodology consisted of establishing 12 sampling stations with different land uses at three times. The National Sanitation Foundation-Water Quality Index (NSF-WQI) was applied to the obtained water quality evaluation data. The main results showed that the stations associated with urban centers presented a higher concentration in the following variables: fecal coliforms, biochemical oxygen demand (BOD) and phosphates. The principal components analysis revealed a close relation between the parameters of fecal coliforms, phosphates and BOD, and the pollution processes by organic matter, which are probably related to domestic and industrial wastewater discharges, and to detergents in urbanized areas. The parameters with the greatest range of values were total dissolved solids and turbidity. These results coincide with what was observed in the correlation analysis. Finally, nitrates showed higher concentrations at stations 6 and 7, associated with agricultural and industrial influence areas (i.e., oil palm crops in the basin). This study about the Acacias River is, thus, extremely important for the region, and concludes that the river’s self-purifying capacity allows improved water quality in the areas where the predominant land use is not associated with human settlements.

Biota colombiana es una revista científica, que publica artículos originales y ensayos sobre la biodiversidad de la región neotropical, con énfasis en Colombia y países vecinos, arbitrados mínimo por dos evaluadores externos. Incluye temas relativos a botánica, zoología, ecología, biología, limnología, conservación, manejo de recursos y uso de la biodiversidad. El envío de un manuscrito implica la declaración explícita por parte del (los) autor (es) de que este no ha sido previamente publicado, ni aceptado para su publicación en otra revista u otro órgano de difusión científica. El proceso de arbitraje tiene una duración mínima de tres a cuatro meses a partir de la recepción del artículo por parte de Biota Colombiana. Todas las contribuciones son de la entera responsabilidad de sus autores y no del Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, ni de la revista o sus editores. Phytoperiphyton refers to the autotrophic component belonging to the periphyton community, composed of aquatic microorganisms that have been monitored for their ecological importance and potential as bioindicators. Few investigations have been carried out on this community in the Colombian Orinoquia, a region with abundant water resources and multiple anthropic pressures, because it is the country’s main agricultural and energy source. Three monitorings were carried out at 12 points along the Acacias-Pajure River, where a total of 41 genera were identified. The highest records of richness were presented at monitoring points 6 and 7, associated with oil palm crops and livestock activity. Navicula (Ochrophyta) and Cosmarium (Charophyta) were the most frequent genera, Oedogonium (Chlorophyta) and Phormidium (Cyanobacteria) the most abundant along the river. El fitoperifiton hace referencia al componente autótrofo perteneciente a la comunidad del perifiton, compuesta por microorganismos acuáticos que han sido monitoreados por su importancia ecológica y potencial como bioindicadores. Son escasos los estudios que se han realizado sobre esta comunidad en la Orinoquia colombiana, región con un abundante recurso hídrico y con múltiples presiones antrópicas, debido a que es la principal despensa agrícola y energética del país. Se realizaron tres monitoreos en 12 puntos a lo largo del río Acacias-Pajure, en donde se identificaron un total de 41 géneros. Los mayores registros de riqueza se presentaron en los puntos de monitoreo 6 y 7, asociados a cultivos de palma de aceite y actividad ganadera. Navicula (Ochrophyta) y Cosmarium (Charophyta) fueron los géneros más frecuentes, Oedogonium (Chlorophyta) y Phormidium (Cyanobacteria) los más abundantes a lo largo del río.