Estimation of greenhouse gas emissions of a tropical reservoir in Colombia

Abstract

Tropical reservoirs are generally flooded in soils with a high content of organic matter. This, combined with high temperatures, favors the generation of carbon dioxide (CO2) and methane (CH4) by biological degradation, contributing to the impact on climate change. A tropical reservoir in Colombia was monitored for 7 years in the pre-fill, fill and post-fill stages, for the last of these during the day and night. Emissions from diffusive fluxes at the surface of the water were measured using a floating static chamber, while inverted funnel methodology was used to measure the fluxes by bubbling. The samples collected in the field were analyzed in the laboratory using a gas chromatograph with a mass detector. The results showed average emissions of 70,892.51 ± 41,079.16-ton CO2eq/year for pre-filling; 178,254.53 ± 105,838.01-ton CO2eq/year for filling; and 466,946.57-ton CO2eq/year for post-filling (for 5 years), concluding that the weather conditions and the filling percentage (Area surface and volume) had an impact on the generation of greenhouse gases at filling and post-filling stages, as did the organic matter present in the area of influence of the sampling point. Higher greenhouse gas emissions were found during the day compared to the results at night, indicating that temperature affects these processes, especially in tropical reservoirs. This study, currently unique in Colombia, will allow directing efforts towards mitigating the impacts of greenhouse gas emissions in tropical reservoirs.

Causes and consequences of recent degradation of the Magdalena River basin, Colombia

“…Data from Sogamoso Reservoir (middle basin; Fig. 1) further indicate substantial greenhouse gas emissions via organic matter decomposition at both in-filling (178,254.53-ton CO 2 eq year À1 ) and post-filling (466,946.57-ton CO 2 eq year À1 ) stages (Rodríguez and Peñuela 2022). The degradation of flooded forest organic material stored in large tropical reservoirs could take up to four to five decades (Campo and Sancholuz 1998;Salgado et al 2020).…”

Impactos ambientales asociados a las hidroeléctricas en Colombia

“…Valencia- Rodríguez et al (2022) registraron los cambios en los inventarios de peces del río Porce luego de la construcción de la hidroeléctrica Porce III, encontrando una reducción de especies nativas y la aparición de especies exóticas. Así, evidenciaron la desaparición de cuatro especies y la aparición de 12 nuevas especies; indirectamente, el estudio resaltó los cambios generados en los hábitats acuáticos ocasionados por la hidroeléctrica.…”

Ajuste de los modelos de velocidad de transferencia de gases en el embalse tropical andino Porce III

“…En Colombia el mayor desarrollo hidroeléctrico se concentra en la región andina. Los estudios previos se han enfocado en la cuantificación de los GEI o la comprensión de las dinámicas espaciotemporales de los flujos y las concentraciones de los gases en embalses hidroeléctricos andinos (Bohórquez-Bedoya et al, 2023;Guérin & León, 2015;León, 2020;León et al, 2020;Rodríguez & Peñuela, 2022). En el presente estudio nos propusimos ajustar los modelos de la velocidad de la transferencia de los gases normalizada (k 600 ) recogidos en la literatura científica a partir de los resultados de las mediciones in situ en un embalse andino para explorar su aplicabilidad en las condiciones de clima y topografía propios de los Andes colombianos.…”