Soil–plant relations in a natural forest inviolate plot at Akure, Nigeria

Abstract

To up-date and extend knowledge of the Akure Strict Natural Reserve an assessment, block by block, of forest in the core of the Inviolate Plot was undertaken in 1974 and complemented with soil sampling. Principal components analysis indicated a gradient of soil reaction and available phosphorus through the core of the plot. Ordination (DECORANA) of floristic data revealed that a floristic trend paralleled the soil trend. In the vicinity of a drainage line, at the western end of the core, soils were lower in available phosphorus, more acid, sandier and texturally more uniform with depth. Typical trees of ferralsols were prominent on these soils but were replaced by species of ferric luvisols, especially members of the Sterculiaceae, on soils of superior nutrient status towards the eastern end. It is suggested that the soil gradients were not effects produced by the trees.Comparison of a 1946 data set with the 1974 data supported the view that the forest had been structurally and floristically stable over the interval between assessments. This is considered justification of the original choice of the area as a Strict Natural Reserve representative of high forest in this part of Nigeria.

What controls tropical forest architecture? Testing environmental, structural and floristic drivers

“…Asian and African forests are taller than South American and Australian forests, which corroborates previous ad hoc comparisons (e.g. Yamakura et al ., ; Ola‐Adams & Hall, ; Milliken, ; de Gouvenain & Silander, ). For a given diameter, trees are taller in Asia and Africa than they are in South America and Australia.…”

“…Differences in maximum tree height between tropical regions have been noted, based on ‘record‐sized trees’, with emergent canopy trees in Asia reaching over 60 m in height, whilst heights of only about 50 m have been reported from Africa and central and north‐eastern Amazonia, and even shorter ‘maximums’ being identified elsewhere in Amazonia and Australia (e.g. Yamakura et al ., ; Ola‐Adams & Hall, ; Korning et al ., ; Milliken, ; de Gouvenain & Silander, ; Liddell et al ., ). However, these generalisations are largely from localised, individual tree measurements.…”

Soil nutrients and beta diversity in the Bornean Dipterocarpaceae: evidence for niche partitioning by tropical rain forest trees

“…Gartlan et al . 1986; Newbery, Renshaw & Brunig, 1986; Ola‐Adams & Hall 1987) and insufficient replication of spatially independent floristic plots within substrates (Proctor et al . 1983; Newbery & Proctor 1984).…”

Measurement of tree diversity in the Nigerian rainforest

“…However, based on previous study in these areas, it has been suggested that differences observed in species diversity are not simply due to phytogeographical effects but that they are related to the underlying edaphic factors (ferrallitic or ferruginous tropical soils; now nitisol and luvisol, respectively; Fig. 2) and rainfall (Hall, 1977;Ola-Adams and Hall, 1987). Hall (1977) sub-divided the ferrallitic soil (nitisol) groups on the basis of geographical location, into western, central and south-eastern sub-groups.…”

“…Ola-Adams and Hall (1987) observed that typical trees growing on ferrasols of lower nutrient status were replaced by species of ferric luvisols, especially members of sterculiaceae, on soils of superior nutrient status along a drainage line from the western to the eastern ends in natural inviolate plots at Akure Forest Reserve, Nigeria.…”