Rico, N.M.M. 2019. Estimativas de Stock de Carbono em zonas ripárias. Dissertação para a obtenção do Grau de Mestre em Gestão e Conservação de Recursos Naturais, Instituto Superior de Agronomia, Universidade de Lisboa, Lisboa, 42 p.
Abstract: Riparian ecosystems have a great potential for long-term carbon storage and sequestration. There is a growing demand on accurate estimations for the Mediterranean region. In this thesis we estimated the carbon (C) stocks of a Mediterranean riparian forest using field data collected in 2018 in the aboveground, understory and organic and mineral soil components. The study area is located in a 3 km-long reach of a Tagus River tributary, Portugal, SW Europe. Allometric biomass models were developed for the Iberian endemic willow (Salix salviifolia) while available equations were applied for black alder (Alnus glutinosa), silver wattle, (Acacia dealbata), narrow-leafed ash (Fraxinus angustifolia), grey willow (Salix atrocinerea) and black poplar (Populus nigra), using Diameter at Breast Height (DBH) and Total Height (H), recorded in 14 circular sampling plots.
The results show that the riparian areas dominated by Acacia dealbata have the highest average total values (trees + litter + soil) of carbon stock (275 Ct/ha), followed by the areas dominated by Alnus glutinosa (134 Ct/ha) and by Salix salviifolia (97 Ct/ha). The tree component presents the largest contributions (76%) to the total carbon reservoir, followed by the leaf component (14%) and the soil component (10%). The results also show a high variability in the average carbon stock values for the tree component and for the litter, these results being related to the density, the size of the vegetation and the succession stage of the different species present in the riparian forest under study. As for the soil component, the results show a reduced variability possibly explained by the morphological characteristics and the high fluvial dynamics found along the entire stream.
This thesis provided the foundations for the assessment of the riparian carbon sequestration in similar Mediterranean riparian forests, a highly relevant Ecosystem Service for the regulation of climate change effects.