Classification of successional forest stages in the Brazilian Amazon basin Dengsheng Lu a,* , Paul Mausel b,1 , Eduardo Brondı ´zio c,2 , Emilio Moran c,3 a Center for the Study of Institutions, Population, and Environmental Change (CIPEC), Indiana University, Bloomington, IN 47408, USA b Department of Geography, Geology, and Anthropology, Indiana State University, Terre Haute, IN 47809, USA c Anthropological Center for Training and Research on Global Environmental Change, Indiana University, Bloomington, IN 47405, USA Received 6 July 2002; accepted 10 December 2002 Abstract Research on secondary succession in the Amazon basin has attracted great interest in recent years. However, methods used to classify successional stages are limited. This research explores a method that can be used to differentiate regrowth stages. The vegetation inventory data were collected in Altamira, Bragantina, Pedras, and Tome-Acu of the eastern Amazon basin. A nested sampling strategy, organized by region, site, plot, and subplot, was employed for field data collection. Above-ground biomass (AGB), forest stand volume (FSV), basal area, average stand height, average stand diameter (ASD), age, ratio of tree biomass to total biomass (RTB), ratio of tree volume to total volume, and ratio of tree basal area to total basal area were calculated at the site level. Canonical discriminant analysis (CDA) was used to differentiate successional stages and to identify the best forest stand parameters to distinguish these stages. This research indicates that the CDA approach can be used to classify successional forest stages, but using RTB or a combination of two stand parameters such as AGB and ASD are more feasible and recommended in practice. # 2003 Elsevier Science B.V. All rights reserved. Keywords: Classification; Secondary succession; Forest stand parameters; Canonical discriminant analysis; Amazon 1. Introduction The Amazon basin contains the largest continuous tropical forest in the world; however, it has suffered serious deforestation for the last 50 years because of road-building, logging, mining, and agricultural and cattle-raising expansion (Moran et al., 1994a; Skole et al., 1994). The large area deforestation has resulted in effects on climate change, biological diversity, hydro- logical cycle, soil erosion and degradation (Shukla et al., 1990; Houghton, 1991; Skole and Tucker, 1993). After deforestation, regeneration of vegetation is common and the resulting landscape often consists of patches of successional forests and agricultural lands. Different succession stages have their own stand structures and different capability in influencing the relationships between successional forests and Forest Ecology and Management 181 (2003) 301–312 * Corresponding author. Tel.: þ1-812-856-5767; fax: þ1-812-855-2634. E-mail addresses: dlu@indiana.edu (D. Lu), gemause@scifac.indstate.edu (P. Mausel), ebrondiz@indiana.edu (E. Brondı ´zio), moran@indiana.edu (E. Moran). 1 Tel.: þ1-812-237-2254; fax: þ1-812-237-8029. 2 Tel.: þ1-812-855-6182; fax: þ1-812-855-3000. 3 Tel.: þ1-812-855-6182; fax: þ1-812-855-3000. 0378-1127/$ – see front matter # 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S0378-1127(03)00003-3