Research Article

Tree Species Diversity in a Naturally Regenerated Secondary Forest in the Ruhande Arboretum, Rwanda

Table 2

Shannon–Weiner (H), species evenness (E), and Simpson’s diversity (D) indices of woody species identified in the study area. Pi stands for the proportion of individuals of a species/plot (n) to the total population of that species (N); ln is the natural log and S denotes the species richness in the study area.

S/NSpecies namen/N (=pi)pi2lnpipi (lnpi)H/lnS

1Markhamia lutea0.4660.217185−0.7640.3560.107
2Polyscias fulva0.2590.066895−1.3520.3500.105
3Cedrela serrata0.0810.006569−2.5130.2040.061
4Tecoma stans0.0240.000568−3.7360.0890.027
5Croton megalocarpus0.0230.000513−3.7880.0860.026
6Prunus africana0.0230.000513−3.7880.0860.026
7Albizia gummifera0.0180.000320−4.0240.0720.022
8Ekebergia capensis0.0140.000205−4.2470.0610.018
9Podocarpus falcatus0.0140.000205−4.2470.0610.018
10Erythrina abyssinica0.0110.000115−4.5350.0490.015
11Maytenus heterophylla0.0110.000115−4.5350.0490.015
12Syzygiummguineense0.0080.000070−4.7860.0400.012
13Erythrococcabongensis0.0080.000070−4.7860.0400.012
14Ligustrum lucidium0.0070.000051−4.9400.0350.011
15Grevillea robusta0.0060.000036−5.1230.0310.009
16Eriobotrya japonica0.0050.000023−5.3460.0250.008
17Acanthus pubescens0.0040.000013−5.6340.0200.006
18Spathodea companulata0.0020.000006−6.0390.0140.004
19Calliandracalothyrsus0.0020.000006−6.0390.0140.004
20Senecio manii0.0020.000006−6.0390.0140.004
21Euphorbia umbellata0.0020.000006−6.0390.0140.004
22Annona reticulata0.0020.000006−6.0390.0140.004
23Nicotiana tabacum0.0010.000001−6.7320.0080.002
24Jacaranda mimosifolia0.0010.000001−6.7320.0080.002
25Cupressus lusitanica0.0010.000001−6.7320.0080.002
26Ficus benjamini0.0010.000001−6.7320.0080.002
27Leucaena diversifolia0.0010.000001−6.7320.0080.002
28Dracaena steudneri0.0010.000001−6.7320.0080.002
.0.293500H′1.7720.532
.D3.407
.E0.532

H, D, and E stand for Shannon–Weiner index, Simpson’s diversity, and species evenness, respectively.