Portal de Eventos, Congreso Colombiano y Conferencia Internacional de Calidad del Aire y Salud Pública

Tamaño de la fuente: 
BIOGENIC VOLATILE ORGANIC COMPOUNDS IN COLOMBIA: FIRST SPECIALIZED MODEL AND DETERMINING EMISSION FACTORS
Jade Alexandra Li Ramírez, Vanessa Catalina Diaz Poveda, Jeannette Del Carmen Zambrano Nájera, Alex Brian Guenther, Beatriz Helena Aristizábal Zuluaga

Última modificación: 21/07/2019

Resumen


A model to estimate Biogenic Volatile Organic Compounds (BVOC) emissions over mountainous regions was developed.  The model permits better analysis of BVOC over Colombia and Andean regions with strong altitudinal changes in short distances, reason why the model was called BIGA. The model can be used in small regions with high resolutions improving the results accuracy.

As a complement, measurements of BVOC were carried out to get Emission Factors (EF) and optimize the model representation over Colombia. It has been reported that tropical regions generate approximately 80% of the global terpenoid emissions (Guenther et al., 2012). However specific EFs for this region have been scarce and the inventory estimations are based in EF determined in other zones. Ten representative species for tropical Andes regions were selected and the EF were determined for trees, crops, scrubs and grass in different thermal floors. The samples were collected following the enclosure method and analyzed by GC/MS-TOF.

The measurements and the model were carried out in Caldas,  high montane tropical region with different thermal floors and different altitudinal gradients (500 to 5200 m.a.s.l), this region is characterized by distinct climactic zones with different ecotypes, that ranged from dry forest valleys to tropical Andean forests, cloud forest, and paramo.

Fourteen types of BVOC were observed such as isoprene, eight monoterpenes and five sesquiterpenes. The highest BVOC fluxes at 30°C y 1000 PAR are emitted by trees mainly by Cecropia peltata and Juglans neotropica with 350610 and 116332 µg m-2.h-1. The species analyzed show that 4% of total BVOC are isoprene, 2% sesquiterpenes and 94% monoterpenes of which the most abundant compound is alpha pinene with 68% of the total emissions.

Preliminary results obtained with the model BIGA revealed critical points of BVOCs in lower elevation zones. The highest emission occurred on the dry period, with differences between dry and wet days around 49% for isoprene and 20% for monoterpene species. The highest fluxes occurred at approximately 15:00 h (LST), with mean fluxes of 3.61 and 1.39 ton m -2 h -1 for isoprene and monoterpenes respectively.