Soils of Mouila Lot 3, Mouila Lot 3 Extension & Ndende Estates, Mougalaba, Douya Onoye & Dola Departments, Ngounie Province, Republic of Gabon, Africa
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TABLE OF CONTENTS
PAGE
EXECUTIVE SUMMARY i
TABLE OF CONTENTS iv
LIST OF TABLES vi
LIST OF FIGURES vii
I. INTRODUCTION 1
1.1. General Introduction 1
1.2. Location and Extent 1
1.3. Access 2
II. THE ENVIRONMENT 10
2.1. Topography and Drainage 10
2.2. Geology and Geomorphology 10
2.3. Climate 13
2.3.1. Rainfall and Raindays 14
III. SOILS OF THE STUDY AREA 15
3.1. Soil Survey Methodology 15
3.2. Description of the Soils 26
3.2.1. Soils Developed Over Sedimentary Rocks 27
Malau Series 27
Kekura Series 27
3.2.2. Soils Developed Over Pediments (Reworked Lateritic Gravels) 29
Malacca Series 29
Gajah Mati Series 29
Terap Series 30
Pedu Series 30
Pedu Series/fine sandy loam 31
Nerang Series 31
Nerang/fine sandy loam Series 33
Dampar Series 33
3.2.3. Soils Developed Over Sub-Recent Alluvium 33
Tebok Series 34
Rasau Series 34
Soils of Mouila Lot 3, Mouila Lot 3 Extension & Ndende Estates, Mougalaba, Douya Onoye & Dola Departments, Ngounie Province, Republic of Gabon, Africa
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TABLE OF CONTENTS (cont’d)
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Nangka Series 34
Serai Series 37
Banar/fine sandy loam 37
Buso Series 37
3.3. Soil Classification 38
3.4. Chemical Characteristics 39
IV. SOIL MANAGEMENT 42
4.1. Introduction 42
4.2. Current Situation 42
4.3. Main Limitations to Crop Production 43
4.3.1. Climate 43
4.3.2. Topography 43
4.3.3. Flooding 43
4.3.4. Soil Fertility 44
4.3.5. Soil Fertility Evaluation of the Soils 45
4.4. Soil Management Groups 47
4.4.1. Soil Management Group A 47
4.4.2. Soil Management Group B 47
4.4.3. Soil Management Group C 53
4.4.4. Soil Management Group D 53
4.4.5. Soil Management Group F 53
4.4.6. Soil Management Group L 53
4.4.7. Soil Management Group P 54
4.5. Overall Yield Potential 54
V. REFERENCES 55
APPENDIX I. Soil Profile Descriptions and Analytical Data
SEMI-DETAILED SOIL MAP AND LEGEND OF MOUILA LOT 3, MOUILA LOT 3 EXTENSION & NDENDE ESTATES
SOIL MANAGEMENT GROUPS MAP AND LEGEND OF MOUILA LOT 3, MOUILA LOT 3 EXTENSION & NDENDE ESTATES
Soils of Mouila Lot 3, Mouila Lot 3 Extension & Ndende Estates, Mougalaba, Douya Onoye & Dola Departments, Ngounie Province, Republic of Gabon, Africa
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LIST OF TABLES
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Table 2.1. Slope classes used in Malaysia 10
Table 2.2. Total monthly rainfall (mm) and raindays for Mouila Lot 3 Estate, 14 MOUTASSOU -Station 1, Estate 12 (2016-2018)
Table 2.3. Total monthly rainfall (mm) and raindays for Ndende Estate, 14 NDENDE -Fera Station, Estate 18 (2016-2018)
Table 3.1. Characteristics of the soil map units of Mouila Lot 3, Mouila Lot 3 23 Extension & Ndende Estates
Table 3.2. Key to the Identification of soils over Sedimentary, Calcareous, 28 Metamorphic Rocks and Tuffaceous Sedimentary Rocks
Table 3.3. Key to the Identification of Skeletal Soils 32 Table 3.4. Key to the Identification of Soils Over Sub-Recent, Non-Accreting 36
Alluvium and Colluvium
Table 3.5. Classification of the soils 38
Table 4.1. Classification of soil nutrient status for oil palm (Goh et al., 1977) 45 Table 4.2. Soil nutrient status of the soils in Mouila Lot 3, Mouila Lot 3 Extension & 46
Ndende Estates
Table 4.3. Evaluation of soil fertility status of the soils in Mouila Lot 3, Mouila Lot 3 46 Extension & Ndende Estates
Table 4.4. Soil Management Groups of Mouila Lot 3, Mouila Lot 3 Extension & 51 Ndende Estates
Soils of Mouila Lot 3, Mouila Lot 3 Extension & Ndende Estates, Mougalaba, Douya Onoye & Dola Departments, Ngounie Province, Republic of Gabon, Africa
vii
LIST OF FIGURES
Figure 1.1. Location of the Republic of Gabon in Africa 3 Figure 1.2. Location of the Olam Palm Gabon S. A.’s Estates in Republic of Gabon 4 Figure 1.3. Location Map of Olam Palm Gabon S. A.’s Estates in Ngounie Province, 5
Republic of Gabon
Figure 1.4. Location Map of Mouila Lot 3, Mouila Lot 3 Extension & Ndende Estates 6 Figure 1.5. Accessibility Map of Mouila Lot 3, Mouila Lot 3 Extension & Ndende 7
Estates
Figure 1.6. Layout Plan of Mouila Lot 3, Mouila Lot 3 Extension & Ndende Estates 8 Figure 1.7. Satellite Imagery of Mouila Lot 3, Mouila Lot 3 Extension & Ndende 9
Estates
Figure 2.1. Contour Map of Mouila Lot 3, Mouila Lot 3 Extension & Ndende Estates 11 Figure 2.2. Geological Map of Mouila Lot 3, Mouila Lot 3 Extension & Ndende 12
Estates
Figure 3.1. Reconnaissance Soil Map of Mouila Lot 3, Mouila Lot 3 Extension & 16 Ndende Estates
Figure 3.2a. Road and Block Map of Mouila Lot 3 and Mouila Lot 3 Extension Estates 18 Figure 3.2b. Road and Block Map of Ndende Estate 19 Figure 3.3a. Semi-detailed Soil Map of Mouila Lot 3 Estate 20 Figure 3.3b. Semi-detailed Soil Map of Mouila Lot 3 Extension Estate 21 Figure 3.3c. Semi-detailed Soil Map of Ndende Estate 22 Figure 3.4. Diagramatic representation of drainage classes 35 Figure 4.1a. Soil Management Groups Map of Mouila Lot 3 Estate 48 Figure 4.1b. Soil Management Groups Map of Mouila Lot 3 Extension Estate 49 Figure 4.1c. Soil Management Groups Map of Ndende Estate 50
