A COMPARATIVE STUDY OF LANDSLIDES AND GEOHAZARD ...

Figure 6.9 : Rock falls along the M1 Road to Karonga, typical
of the Chiweta beds. These have been a major
cause of accidents 105
Figure 6.10 : One of the three fish ponds that were destroyed
During the 2003 Landslides in the Ntchenachena Area 110
Figure 6.11 : Active erosion in most of landslide channels,
degrading the environment further. This is typical of the
Ntchenachena Area 110
Figure 6.12 : Position where landslide debris dammned the Lutowo
River which resulted in the flooding of the Mzinga River.
Debris remains can be seen at the site 111
Figure 6.13 : Bank collapse caused by landslides, common at all
Study Areas and contributing to siltation of rivers.
This is an example from the Livilivi Catchment 112
Figure 7.1 : Soil cracking and deformation; an indication of
instability, common in the Ntchenachena and the
Livilivi Areas 114
Figure 7.2 : Annual rainfall Totals for Rumphi and Ntcheu Districts 126
Figure 7.3A : Daily Rainfall for March for the Ntchenachena and
Chiweta Study Areas. Note the critical rainfall that
Triggered the events 127
Figure 7.3B : Daily Rainfall for January for the Mvai and Livilivi Study
Areas. Note the critical rainfall which caused the
Landslides 128
Figure 7.4A : Monthly Rainfall Totals for Ntcheu District (1977 – 2005) 128
Figure 7.4B : Monthly Rainfall Totals for Rumphi District (1977 – 2005) 129
Figure 7.5 : Cassava cultivation in the Ntchenachena Area
leaves the gound bare, thereby making it prone to
landslides 131
Figure 7.6 : Destruction of the Mvai/Dzonzi Forest Reserves
contributing to the loss of shear strength of the soil.
In the foreground, landslide scar is clearly visible 132
Figure 7.7 : Charcoal making in the Livilivi/Mwai Catchments
contributing to instability. In some areas, the Miombo
woodlands have completely disappeared 132
Figure 7.8 : Soils which liquefied and dried are common at all
study areas. The photo represents liquefaction at the Lutowo
of the Ntchenachena Area 135
Figure 7.9 : Structural rock weaknesses through which water
Penetrated, causing high cleft pressure and
Landsliding at the Mvai Study Area 137
Figure 7.10 : Part of Kasese Forest where vegetation was
observed to contribute to stability. All the observed
landslides occurred outside the Forest 139
Figure 7.11 : Vegetation wedging boulders apart at the Mvai Area,
contributing to mechanical weathering. Rockfalls were
observed to have been caused by root wedging 141
Figure 7.12 : Destruction of the shrubs and grass in the
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