[en] Landscape Ecological Survey of the Bipindi-Akom II ... - ITTO

Nyangong type. The predominant forest type is the submontane Maranthes-Anisophyllea
community (I). In general, the vegetation is not affected by human activity.
7.3.2 Ah1: isolated hills above 700 m asl, well drained soils
These mapping units are found along the fringes of the Bingalanda massive in the eastern part
of the TCP area where they cover some 880 ha. The altitude of the isolated hills vary from 700
to 900 m as!. Valley bottoms are not included in this unit. The soils are very clayey (Nyangong).
The predominant forest type is the submontane Maranthes - Anisophyllea community (I).
Human activities have not altered the vegetation in these units.
7.3.3 Bh2: complex of hills between 500 and 700 m asl, well drained soils
Mapping units Bh2 are complexes of hills between 500 and 700 m asl, and are found in the
strongly dissected eastern part of the TCP research area. They cover large surfaces just west of
the Bingalanda mountain range and have a general SW-NE orientation. In addition, Bh2 units
are found in the southwestern part of the TCP research area, where they form the foothills of the
mountain range that is situated west of the TCP research area. The total surface area of these
mapping units is some 13,890 ha. The dominant soils are very clayey (Nyangong). Valley
bottoms are narrow and cover only limited surfaces. The vegetation is predominantly primary
and old secondary lowland forest of the Podococcus-Polyalthia community (Ha). Human
activities have not altered the vegetation of these units.
7.3.4 Bh1: isolated hills between 500 and 700 m asl, well drained soils
These mapping units are found scattered as small patches in the eastern part of the TCP area.
Although their total area does not cover more than 3,820 ha, the isolated hills form a
characteristic aspect of the landscape. The elevation of the hills is between 500 to 700 m as!.
The soils are very clayey and belong to the Nyangong type. Valley bottoms are almost
completely absent. The vegetation is predominantly primary and old secondary lowland forest
of the Podococcus-Polyalthia community (Ha). Human activities have not altered the vegetation
of these these units.
7.3.5 Bu2: hilly uplands between 500 and 700 m asl; well drained soils
The hilly uplands of the Bu2 units cover some 19,700 ha. They are located at the foot of the
Bingalanda mountain range in the eastern part of the TCP area and in the northeastern part of
the area. The uplands are strongly dissected and valley bottoms are estimated to cover between
5 and 10% of their surface. The soils are an association of very clayey Nyangong soils and the
clayey Ebom ones. The predominant vegetation type of these units is the primary and old
secondary lowland forest of the Podococcus - Polyalthia community (Ha). The valley bottoms
are characterized by poorly drained soils and by the swamp forest of the Carapa - Mitragyna
community (III).
The units are to a limited extent affected by agricultural practices. Only along the roads some
low intensity encroachment is visible on the 1984-1985 air photo's. photo'S. In these areas, especially
near the villages Nyangong and Ebemvok, the composition of the vegetation has gradually been
changing into a mosaic of thicket of the Macaranga - Chromolaena community (V), young
secondary forest of the Xylopia - Musanga community (IV), and lowland forest of the
Podococcus - Polyalthia community (Ha).
7.3.6 Bu1: rolling uplands between 500 and 700 m asl; well drained soils
Rolling uplands between 500 and 700 m asl are only found in the most eastern part of the TCP
area, where they cover a total surface area of 5,400 ha. The rolling uplands are moderately
dissected and valley bottoms are estimated to cover 10 to 15% of these mapping units. In places,
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