A COMPARATIVE STUDY OF LANDSLIDES AND GEOHAZARD ...

Literature reveals that landslide studies have been carried out extensively in the
southern parts of Malawi (Gondwe et al., 1991; Poschinger et al., 1998; Cheyo, 1999;
Mwenelupembe, 1999; and Manda, 1999). Little has been done in Central and Northern
Malawi, except for studies carried out by Dolozi and Kaufulu in 1992, and Msilimba in
2002 in Central and Northern Malawi, respectively (Dolozi and Kaufulu, 1992; Msilimba,
2002 and Msilimba and Holmes, 2005). However, it should be noted that most of the
landslides which occurred in Southern Malawi caused substantial damage to property
and deaths of people.
Recently, a number of landslides have occurred in the Ntchenachena and the Chiweta
areas (Northern Malawi), and in the Mvai and the Livilivi areas (Central Malawi). Reports
from local radio stations and newspapers indicate that landslides are a common
phenomena in these areas. Some events have caused significant loss of property and
life. This could be an indication of increasing instability and yet little is known about
preparatory and triggering factors, and the severity of old landslides. Therefore, a
detailed research work and susceptibility mapping was required to determine landslide
hazards and appropriate mitigation measures that can be devised to prevent further
occurrences or minimize the impacts. It was also imperative to study how people
perceive these events and cope with them.
1.2 Aims of the Study
It is extremely important to recognise the reasons that make an area susceptible to
sliding and to acknowledge factors that trigger the movement of the rock or soil mass
movement. This helps the researcher to arrive at a precise and correct diagnosis of
effective remedial measures. The variety of landslide types reflects the diversity of
factors which are responsible for their origin. The diversity causes a complexity in
describing the factors and their relationships (Zoruba and Mencl, 1969; Crozier, 1984,
1986 and 1989; and Coch, 1995).
Therefore, this study was aimed at identifying and assessing the contribution of various
causal factors such as structural weaknesses in rock/soil mass, changes in water
content, changes and effect of ground water regime, weathering of slope forming
materials, changes in land use, topography and vegetation cover change towards the
occurrence of landslides. The study aimed to determine the inter-relationship between
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