| Method |
p.7473 left column 5th paragraph:"[Investigators] estimate the number of tropical tree species from a standardized
dataset of old-growth tropical forest tree inventories,
including gymno- and angiosperms with diameters at breast
height (dbh) =10 cm. This dataset contains tree species abundance
data for 207 1° grid cells (locations) originally dominated
by closed-canopy forests across the tropics (Fig. 1). By calculating
Fisher’s alpha (ref 16) at the pantropical scale and combining
this value with the estimated potential number of stems present within 500 km of each location, [investigators] arrive at a minimum number of tropical tree species of at least ~40,000 and possibly more than ~53,000 (Table 1), i.e., at the high end of current total estimates of 37,000 (ref 7), 43,000 (ref 8) and 50,000 (ref 6), which are based on expert opinion." |