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- Relação hipsométrica geral para Eucalyptus globulus Labill. em PortugalPublication . Tomé, Margarida; Ribeiro, Fernanda; Faias, SóniaTree height is an important variable for determining the tree volume and the stand volume. Sometimes tree height is not measured in the field, and for predicting it an equation is used as a function of tree diameter and other stand variables. The existing equations that express hypsometric relationships have some limitations at the application level. In this work, a general equation has been developed with data that represent all the area of eucalyptus plantations in Portugal.
- Ajustamento simultâneo de equações de biomassa de pinheiro manso no sul de PortugalPublication . Correia, A.; Tomé, Margarida; Faias, Sónia; Freire, João; Carvalho, P.O.We present a system of alometric biomass equations for aboveground compartments for Pinus pinea L. that allows biomass estimation with information from conventional forest inventories. We harvested 40 trees located in south of Portugal and separated and weighed all the aboveground components: needles, stem bark, branches and stem. The equations were simultaneously fitted using seemingly unrelated regression. This method allows the compatibility of the partial allometric equations with the equation for total biomass aboveground that corresponds to the sum of those 4 equations. The models were better for stem (R2adj.=0.85) and bark (R2adj.=0.83) and worst for branches (R2adj.=0.79) and needles(R2adj.=0.71). Crown biomass was always high compared with aboveground biomass, independently on stand characteristics. However it may be exacerbated by artificial pruning that is carried out to increase crown expansion for pine nut production. The different stand management circumstances from where trees harvested were selected may explain the worst fitting for crown components.