Geology Reference
In-Depth Information
moist forest species. Another effect of the marked
southen dry season is dominance of
Painai
excelsa,
and it may account for the apparent
absence of
Entandrophragma excelsum
from the
Uzungwa.
Secondary species include:
Anthocleista grandi-
flora, Macaranga kilimandscharica, Neoboutonia
macrocalyx
and
Polyscias fu lva.
Easten Arc
endemics include:
Allanblackia stuhlmannii,
Beilschmiedia kweo, Dypetes usambarica
(with a
subspecies on the Kenya coast),
Isoberlinia schf-
fleri,
and
Poyceratocarpus schfieri.
Endemics in the
north include
Mammea usambarensis.
Other rees
include:
Aningeia adoi-fi edericii, Besama abys -
stntca, Canthium oligocarpum
subsp.
captum,
Chysophylum
goungosanum, Cleistanthus
poystachyus, Cola greenwayi, Conus volkensii,
Craibia brvicauata, Cyptocaya liebertiana,
Dypetes gerrardii, Ficalh oa lauiolia, Ha l/ea
rubrostipulata, Myrianthus holstii, Newtonia
buchananii, Ochna holstii, Ocotea usambarnsis,
PoOcarpus alcatus, Strombosia shfieri, Syzygium
guineense
subsp.
af romontanum, Xy malos monosp ora.
Uzungwa Mountains is reflected in single-species
canopy dominance of
Parinai excelsa,
in conrast
to muli-species dominance of the Usambara or-
ests; and in the more frequent occurrence of
deciduous species of
Albizia.
Typical secondary
species include
Ha ungana maagascarinse,
Macaranga capensis, Trema guineense
with
Cyli- li-
comopha parvlora
at higher alitudes, and
Sapium
elliptium
at lower alitudes. The inroduced
Maesopsis eminii
has become a successful pioneer
in the much disturbed East Usambara forests.
Eastern Arc endemics include
Anisophylla obtusi-
olia
and
Cphalosphaera usambarensis.
Usambara
endemics include
Englerodendron usambarense;
southern endemics include
Oaoknema oientalis
and
Sibangea pleioneua.
Other rees include:
Allanblackia stuhlmannii,
Aningeria pseuOracemosa, Antiesma membrana-
ceum, Isoberlinia schfieri, Lptonychia usambarensis,
My rianthus holstii, Ne wtonia buchananii, Odyenea
zimmermannii, Pachystela msolo, Strombosia schf-
lei, Trichi/ia dregeana, Trilpisium maagas -
canense.
In addiion to dominance by
Parinari excelsa,
drier types of submontane forest would be indi-
cated by species characterisic of dry montane
forest, dry lowland forest and woodland. This
ype of forest is restricted in extent because there
are few areas where rain shadows occur at this
alitude.
Submonane orest
Alitude: 800-1400 m. Rainfall: > 1500
mm/year.
Synonyms: Moist forest (CCTNCSA, 1956).
Intermediate Forest (Moreau, 1935).
Lower alitude ypes of submontane moist
forest (White, 1970). Lowland rain forest
(Greenway, 1973). Submontane rain forest
(Pocs, 1976c). Zanzibar-lnhambane
transiional rain forest (White, 1983).
Canopy: 25-40 m with emergents to 50 m.
Basal area: 30-70 m2/ha. Stem sizes:
Many large trees >50 cm dbh with a
relaively high proporion > 100 cm dbh.
Stem densiies: 170 stems > 20 cm
dbhha.
Lowland forest
Alitude: <800 m. Rainfall: > 1500 mm/year.
Synonyms: Moist forest (CCT NCSA, 1956).
Lowland forest (Moreau, 1935). Lowland
moist forest (White, 1970). Lowland rain
forest (Greenway, 1973). Lowland semi-
evergreen and evergreen rain forest (Pocs,
1976c). Zanzibar-lnhambane lowland rain
forest (White, 1983).
Canopy: 25-40 m with emergents to 50 m.
Basal area: 20-50 m2/ha. Stem sizes:
Many large trees >50 cm dbh with a
relaively high proporion > 100 cm. Stem
densiies: 140 stems > 20 cm dbh/ha.
Submontane forest differs from montane forest
in that it contains lowland species such as
Af roser-
salisia cerasifera, Milicia excelsa
and
Parkia ili-
coidea.
Otherwise these forest types overlap in
florisic composiion and are similar in sructure.
As with montane forest, the long dry season in the
Lowland forest differs from submontane forest
Search WWH ::
Custom Search