Species topological roles in the networks
In the Asenanyo Forest Reserve, liana species in edge site were mainly
peripherals, with the exception of four species (C .cucullata , M . chrhysophylla , M .guineensis , Morinda morindoides ) which acted as
connectors (Figure 4a). Millettia lutens and Tiliacora
dielsiana were the only module hub species of lianas in edge site.
Network hubs did not occur among lianas in edge site. The connector and
module hub species constituted 15.4 % of liana species in this site.
The majority of the tree species also performed specialist role in edge
site, but seven of the species (C . mildbraedii ,Hymenostegia afzelii , Trilepisium sp., Baphia
nitida , Entandrophragma utile , Triplochiton scleroxylon ,N . papaverifera ) were connectors (Figure 5a). These
generalist species formed 25 % of the tree species. In interior site,
we had no liana connectors and network hubs, but two module hubs existed
in this site (M . guineensis , S . elegans ),
making up 5.6 % of liana species in interior site (Figure 4b). The rest
of the liana species served as peripherals in interior site. Trees in
interior site were mostly peripherals, with only one connector
(Albizia zygia ) and one module hub (Bec) species (Figure 5b), but
no network hub trees. These generalists were 5.7 % of the total tree
species in this site. Within deep-interior site, we recorded two liana
connectors (G . simplicifolia and S .preussii) and one liana module hub (S . elegans )
(Figure 4c), which together made up 10.3 % of the liana species in the
site. The rest of the liana species in deep-interior site were
peripherals. There were three connectors (C . mildbraedii ,Amphimas pterocarpoides , Turraeanthus africanus ) and one
module hub of tree species (Homalium dewevrei ) in deep-interior
site, but there was no network hub species (Figure 5c). These tree
species composed of 8.6 % of the total number of species in
deep-interior site.
We recorded G . simplicifolia , C . tarquense ,A . kamerunensis and Combretum paniculatum as
connector liana species within edge site of the Suhuma Forest Reserve,
while the majority of the liana species were peripherals (Figure 6a).C . africanus was a network hub in the edge site. The above
mentioned generalists constituted 11.4 % of the total liana species.
Five tree species acted as connectors in edge site (C .mildbraedii , Celtis philippensis , Entandrophragma
angolense , N . papaverifera , Trichilia prieuriana ),
while one tree species was identified as a module hub (Calpocalyxbrevibracteatus ) (Figure 7a). Network hubs of tree species were
not recorded in edge site. Together, the connector and module hub
species formed 9.5 % of the total number of tree species in edge site.
In interior site of Suhuma Forest Reserve, most of the liana species
were peripherals. Generalist liana species were module hubs (A .pentagona , C . africanus , N .acuminata , M . fulvum ) and network hub (M .chrysophylla ), but with no connector species (Figure 6b). The
above mentioned generalist species formed 12.2 % of liana species in
interior site. The majority of the tree species in interior site of
Suhuma Forest Reserve acted as peripherals. We did not identify
connector tree species in this site, but a few module hub species
occurred there (Albizia adianthifolia , C .mildbraedii , Sterculia oblonga ) (Figure 7b). These
generalist species formed 6.5 % % of the tree species. In
deep-interior site, lianas were mainly peripherals, except for G .simplicifolia , C . africanus , Neuropeltis
prevosteoides and Alafia sp., that acted as connectors (Figure
6c). The above-mentioned generalists formed about 9.8 % of the total
liana species. Tree species in deep-interior site were generally
peripherals, except C . mildbraedii and Ricinodendron
heudelotii (connectors), and Amp and Gut (module hubs) which formed 8.7
% of the tree species (Figure 7c).