Mgambo Forest Reserve: A biodiversity survey. - Eastern Arc ...

Mgambo Forest Reserve
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4.3.1.5 Ecological type
Just 29 individuals representing 5 species (5% of total) recorded within vegetation plots were
forest dependent (Table 7). However, the majority individuals recorded were from species that
were forest dwelling (Table 7). Figures 9 and 10 shows the distribution of forest dependent
individuals and species. The south-western section of the reserve contained the most forest
dependent species.
Non-forest individuals and species were found widely distributed throughout the forest reserve
(Figures 11 and 12). This widespread distribution resulted in the majority of the forest reserve
being woodland and grassland habitat and this reflects the significant disturbance pressure the the
forest reserve is under.
Table 7 Summary of ecological type of tree and shrub species recorded in the 50m x 20m vegetation plots
(based on Table 4).
Ecological Type Number of
species
% of total
species
Number of
individuals
% of total
individuals
Forest dependent (F) 5 5.0 29 3.4
Forest dwelling (f) 62 61.4 437 50.9
Other (O) 27 26.7 374 43.6
Unknown (?) 7 6.9 18 2.1
Total 101 100 858 100
4.3.1.6 Habitat
Flora recorded from the vegetation plots of Mgambo FR was most commonly categorised within
the lowland forest habitat type. A total of 39 (38.6%) species and 363 (42.3%) individuals were
categorised as lowland forest species. There were only 4 species, Acacia mellifera, Acacia
nilotica, Grewia bicolor and Sterculia africana, that were categorised as sub-montane species and
1 species, Strychnos innocua, categorised as a montane species (Figure 13 and 14). Despite the
habitat categories of these species, they were all found in woodland lowland areas. Many other
species (48 in total) were categorised as combinations of lowland with submontane and/or without
montane forest habitats.
Table 8 Summary of habitat type for tree and shrub species recorded in the 50m x 20m vegetation plots
(based on Table 4).
Habitat
No. of
species
% of total
species
No. of
individuals
% of total
individuals
Montane (M) 1 1.0 2 0.2
Submontane & montane (S&M) 5 5.0 15 1.7
Submontane (S) 4 4.0 71 8.3
Lowland, submontane & montane (L&S&M) 18 17.8 185 21.7
Lowland & submontane (L&S) 25 24.8 201 23.4
Lowland (L) 39 38.6 365 42.5
Unknown (?) 7 6.9 19 2.2
Total 101 100 858 100
Table 9 Submontane and/or montane species and the altitudinal ranges at which they were recorded in
Mgambo FR.
Family Species Altitudinal range (masl)
BALANITACEAE Balanites aegyptica 420-505
FLACOURIACEAE Caloncoba welwitschii 505
LEGUMINOSAE Acacia mellifera 400
LEGUMINOSAE Acacia nilotica 510
LEGUMINOSAE Milletia dura 540-570
LOGANIACEAE Strychnos innocua 360-430
SAPINDACEAE Allophylus melliodorus 480
East Usambara Conservation Area Management Programme Technical Paper 59