Estimación de la productividad primaria neta en coberturas de bosque seco tropical a partir de imágenes satelitales Landsat 8 Oli Tirs

Abstract

With the spectral response of plant coverages, it is possible to formulate models in which Net Primary Productivity (PPN) is a product of Absorbed Photosynthetically Active Radiation (APAR) and the Radiation Use Efficiency (RUE), quantifiable variables from satellite information. This study aims to estimate PPN (Foliar and Global) in seven fragments of tropical dry forest in the villages Pozo Azul and Agua Blanca (Girardot-Cundinamarca), from eight Landsat 8 OLI TIRS satellite images obtained between July 2013 and November 2016. The APAR is significantly different in each fragment, being possible to identify three groups: fragment 1 (16.77 MJ/m2), fragments 2 to 6 (on average 15.32 MJ/m2) and fragment 7 (14.02 MJ/m2). The PPN estimation was made from the EUR(Foliar) (0.28 g/MJ) calculated from the foliar production follow-up to six representative species and according to the observations of Monteith (1972), we used 1.5 g/MJ as EUR(Global) according to the type of coverage. The average PPN(Foliar) is 4.36 g/m2/month, where the fragment 1 is the most productive (4.75 g / m2 / month) as a result of the lack of anthropic intervention, while in fragment 7, productivity doesn’t exceed 3.97 g/m2/month. Regarding PPN(Global), an average of 22.73 g/m2/month, we concluded that the productivity is influenced to the irregularity of the shape of the fragment and its surface, variables mainly conditioned by the topography and the degree of antropic intervention.