Ecology and conservation
The type of ecological habitat may have a possible effect on the
morphology of L. columnaris (Mabberley 1974b). This observation
has to be developed in future studies. Our study observed that
populations grow in a mosaic of ecological habitats, latitudinal, and
elevational gradients. Indeed, we observed phenotypic variation in some
traits, for example, in plant height, size of the inflorescence, leaves,
and flower colour. L. columnaris is smaller in height,
inflorescence, and leaf length at a higher elevation (approx. 3000m) and
lower elevation (1000m). Elevations between 2000 to 2600m, the variation
is spectacular with greater height, inflorescence number, colour, and
leaf length.
The populations of L. columnaris in mainland Cameroon are at high
risk of local extirpation because of excessive anthropogenic pressure on
montane forest fragments. Only for the populations on Mt. Cameroon,
which is a National Park, have conservation protection plans. The
scenario in Bioko for this giant lobelia and the Afromontane forest is
better. Bioko has an active conservation procedure in two of the three
sky islands (Müller & Pócs 2007). Moreover, South Bioko is undisturbed
because of low human population density and supports the highest numbers
of plant and animal species on the island (see Jones 1994).