A Comparison of the Structure and Composition of Montane and Lowland Tropical Forest in the Serranía Pilón Lajas, Beni, Bolivia Back to Main Page Table 6. A comparison of the floristic similarities of five one hectare plots established in humid forest in eastern Bolivia; only those plots with more than 85% of the taxa determined to the species level were selected for comparison; values are the number of species found in both plots (nc ), Sorensen's coefficient of similarity based on presence vs. abscence (Sc ), and Sorensen's coefficient of similarity based on quantitative data (Sq); locality data is as in Table 4.   Cumbre Pilón Río Colorado Bosque Chimanes Río Saguayo Alto Ivon   nc Sc Sq nc Sc Sq nc Sc Sq nc Sc Sq nc Sc Sq Cumbre Pilón - - - 23 0.20 0.15 24 0.23 0.14 23 0.22 0.18 1 0.04 0.01 Río Colorado       - - - 22 0.28 0.36 25 0.32 0.35 8 0.09 0.10 Bosque Chimanes             - - - 24 0.33 0.31 7 0.06 0.12 Río Saguayo                   - - - 5 0.06 0.04 Alto Ivón                         - - - Total species 146     78     78     67     94     Sc = 2c / a + b, where c is the number of species in common between two localities; a and b are the total number of species found in each of the two localities A and B. Sq= 2nc / na + nb , where nc is the sum of the lower of the two abundance values (i.e., number of stems) for each species that occurs at both of the two localities; na + nb , is the sum of the total abundance values for the two localities A and B (Magurran, 1988).