Land cover changes and landslide occurrence: a case of Tirap division in Elgeyo Marakwet County, Kenya.

Abstract

Landslides are described as downward movement of soil and rocks resulting from naturally occurring vibrations, earthquakes, changes in water content, removal of lateral support, loading with weight and weathering or human manipulation of water causes and the slope composition. They can be different types of movements: falls, slides, topples, lateral spread and flows. Areas near steep mountain slopes with high rainfall occurrence are susceptible to landslides (Walpole, 2013). Landslide occurrences have continued to increase in the last few years in several parts of mountainous areas of Kenya and have both social and economic impacts which are mainly loss of life, agricultural land, crops and livestock as well destruction of infrastructure. In between 2004 to 2007, over 2304 people have been affected by landslides in different parts of Kenya (Kigomo and Mburu, 2009). The general factors that influence landslides in Kenya can be grouped in two categories; natural factors such as geomorphology, lithology, slope terrain and rainfall and human activities such as agriculture, changing land uses and mining. During the rainy season, various parts of the eastern slopes of the Cherang’any hills witness heavy landslides especially as seen in the last twenty years. One such area greatly affected is Embobut and Embolot Locations in Tirap division, Elgeyo Marakwet County. Often those affected are left to their own devices when this disaster strikes. There is little government help and is often short term and ad-hoc, if at all any. There are no long term solutions that have been proposed and implemented in a policy, institutional or legal framework context to those help those affected by this natural hazard and disaster which causes untold misery and poverty since those affected lose their shelter, food crops and livestock in the immediate aftermath or in the long term if the land that is swept by a slide happens to be the only land they own. They are reduced into a life of poverty and penury. This research thesis study investigated the extents to which changes in land use and cover, rainfall intensity and slope gradients have all come into play to create the right conditions for landslide occurrences in Tirap division. It also looked at the socio-economic effects of these landslides to the people of this area. Land use cover changes were studied using old maps and satellite imagery to show the changing land use patterns over time. Household questionnaires, Key Informant vii questionnaires, observation and photography are some of the primary data methods that were used for data collection. Secondary data was also used to gather existing information on landslides and best practice policy interventions around the world. The study found out that there had been profound land use cover changes since the 1960s to the present day due to extensive and incessant human activity. This was because of increased human population and the attendant need to cultivate more land to feed more people. A large swath of Embobut forest has been deforested. This steep land that lies exposed easily soaks in rainfall water to saturation, subsequently leading to increased cases of landsliding in the division. The lower settled escarpment lands are steep and mountainous with slopes in excess of 25 degrees. These increased landslides have continued to cause loss of human lives, livestock, property and land within Tirap division. The study makes recommendations that include proposals on how landslides can be mitigated by environmental planning methods and requisite policy measures.