Environmental Engineering Reference
In-Depth Information
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Ghana
Guinea
Figure 16.5 Abundance diversity of plant species in 0.4 ha study field
Girth-class distribution
Whereas
D. oliveri
was the most abundant species per plot encountered in
Guinea,
A. leiocarpus
was the most abundant in Ghana.
The girth-class distribution of woody species in the plots inventoried in the two
countries is presented in Figure 16.6. Generally regeneration of woody species is
high in the plots studied, particularly in Guinea (Kouroussa-Moussaya).
Similarly, there is an appreciably higher representation of pole-size wood species
(50-100 cm) in Guinea.
In general, the representation of girth classes that are between 150 and 200 cm is
twice to thrice as much in the plots studied in Guinea than in Ghana. For example,
except for Kouroussa-Moussaya, larger stems (200-250 cm) are less represented
and even absent altogether in Asantekwa, whereas in Binguri, Bognayili, and Dugu-
Song (all in Ghana), this girth class is represented only in small numbers. Again,
the 250-300 cm girth-class wood species is also better represented in the plots at
Kouroussa-Moussaya in Guinea than in the plots sampled in Ghana. Therefore, rep-
resentation of much larger stems (
300 cm) in plots studied in Ghana is estimated
to be less (i.e. 33-50 per cent) than what was observed in plots in Guinea.
Height-class distribution
The protected forest at Binguri showed twice as many regenerating tall species
than at Kouroussa-Moussaya (Figure 16.6). A progressive increase in pole-size
numbers at Dugu-Song and in other plots in Ghana is observed (Figure 16.7).
By contrast, there appears to be a successive reduction and loss in numbers of
