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

5.2.4 Valley Bottom soils .................................... 42
5.2.5 Soil classification ...................................... 43
5.3 Soil physical characteristics ................................... 45
5.3.1 Texture ............................................ 45
5.3.2 Bulk density ......................................... 46
5.3.3 Water retention ....................................... 47
5.4 Soil chemical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.4.1 pH and exchangeable acidity .............................. 47
5.4.2 Organic carbon and total nitrogen ........................... 48
5.4.3 Available and total phosphorous ............................ 50
5.4.4 Cation exchange capacity and exchangeable bases ................. 50
5.4.5 Clay Clay mineralogy ...................................... 51
5.4.6 Nutrient contents contents ...................................... 52
5.4.7 Conclusions ......................................... 53
5.5 Soil-Iandform relationships and soil genesis ......................... 53
5.5.1 Soil and landform landform relations ............................... 53
5.5.2 Soil genesis .......................................... 55
6. VEGETATION .............................................. 57
6.1 6.1 Literature Literature review review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 57
6.2 Botanical diversity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 59
6.3 Vegetation classification ..................................... 59
6.4 Plant Plant communities ......................................... 62
6.4.1 6.4.1 Maranthes - Anisophyllea community (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 62
6.4.2 Podococcus - Polyalthia Polyalthia community community (IIa) ...................... 64
6.4.3 Strombosia - Polyalthia community (lib) ....................... 64
6.4.4 Diospyros - Polyalthia community (IIc) ........................ 65 65
6.4.5 6.4.5 Carapa - Mitragyna community (Ill) ......................... 66
6.4.6 Xylopia - Musanga community (IV) . . . . . . . . . . . . . . . . . . . . . . . . .. 67
6.4.7 Macaranga - Chromolaena community (V) ..................... 67
7. LANDSCAPE ECOLOGICAL MAP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
7.1 Legend Legend ................................................ 69
7.2 Land use ............................................... 69
7.3 Land mapping units ........................................ 70
7.3.1 Am: mountains above 700 m asl, well drained soils ............... 70
7.3.2 Ahl: isolated hills above 700 m asl, well drained soils .............. 71
7.3.3 Bh2: complex of hills between 500 and and 700 m asl, well drain soils ...... 71
7.3.4 Bh 1: isolated hills between 500 and 700 m asl, well drained soils . . . . . .. 71
7.3.5 Bu2: hilly uplands between 500 and 700 m asl; well drained soils ...... 71
7.3.6 Bul: rolling uplands between between 500 and 700 m m asl; well drained soils ..... 71
7.3.7 ChI: isolated hills between 350 and 500 m asl, well drained soils ...... 72
7.3.8 Cu2: hilly uplands between 350 and 500 m asl; well drained soils ...... 72
7.3.9 7.3.9 CuI: rolling uplands uplands between 350 and 500 m asl; well drained soils soils ..... 72
7.3.10 7.3.10 Dhl: isolated hills below 350 m asl, moderately well drained soils . . . .. 73
7.3. 11 Du2: hilly uplands below below 350 m asl; moderately well well drained soils soils . . . .. 73
7.3.12 DuI: rolling uplands below 350 m asl; moderately well drained soils ... 73
7.3.13 Dpd: dissected erosional plains below 350 m asl; moderately well well drained drained
soils .............................................. 74
7.3.14 Ev: Ev: valley valley bottom; poorly to very poorly drained soils ............. 74
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