Nyangena, John2019-10-222019-10-222018-11http://ir-library.ku.ac.ke/handle/123456789/19856A Thesis Submitted in Fulfillment of the Requirements for the Award of the Degree of Doctor of Philosophy (Environmental Planning and Management) in the School of Environmental Studies, Kenyatta UniversityThis study investigated the implication of drought and land use changes on pastoral livelihood in Oltiasika area of Chyulu-Amboseli ecosystem. The study objectives were to assess the relationship between drought and vegetation conditions, assess biophysical changes that have occurred in Oltiasika between 2009 and 2016, and analyse the effect of livelihood diversification on household drought resilience. Rainfall data was obtained from Soil and Water Assessment Tool (SWAT) climate database, Moderate Resolution Imaging Spectro-radiometer (MODIS) Normalized Difference Vegetation Index (NDVI) data was obtained from the University of Natural Resources and Life Sciences (BOKU) in Vienna, while land use changes detection was analysed using Google Earth images. Primary data was generated through a cross-sectional survey carried out in January-February 2015 in a sample of 354 households. Auto regression analysis of Normalized Difference Vegetation Index (NDVI) and Standardized Precipitation Index (SPI) was carried out to investigate the relationship between drought and vegetation greenness. Herfindahl-Hirschman Index was computed to measure the degree of household livelihood diversification and Ordered Logit Regression analysis was performed to examine the effect of diversification on household resilience. The results showed that between 1983-2014 145 months were categorized as drought based on their Standardized Precipitating Index (SPI). Months with severe drought (SPI value between -1.50 and -1.99) were the most common (69 months) followed by those with mild drought (SPI ranging between 1-.00 and -1.49) in 57 months, while extreme drought (SPI less than -2.00) occurred in 19 months. The vegetation greenness for the period 2000-2016 produced Normalized Vegetation Difference Index (NDVI) with a mean of 0.34, which is below the normal mean (0.5). The driest period in the area was observed in September 2004 when the NDVI value was 0.193, while the wettest was in December 2006 with NDVI value of 0.62. The study found a significant relationship between NVDI and SPI with an R2 of 59.6% and revealed that vegetation condition responded positively to drought with a lag period of two months. In the sampled sites between 2011 and 2016 the area under cultivation increased by 707% while the number of Manyatta settlements increased by 37.5%. Results of the Herfindahl-Hirschman Index showed that 22.73% of the households had an index of less than 0.25 and only 2.84% had an index greater than 0.5. Further, household’s capacity to meet food requirements decreased with age and household size, while, education, total assets and net non-farm income had no effect. A unit change in the degree of diversification was associated with a 17.1% more likelihood for a household to fall in a strong category to meet food requirement, a 13.5% less likely to belong to a moderate category and 9.2% less likely to fall in a low category. Biophysical changes taking place in the area had limited the availability and accessibility of pasture upon which pastoralism thrive. While crop farming may provide answers to the immediate challenges confronting pastoral communities, the prevailing cultural and physical limitations makes this livelihood an ecologically destructive system. Pastoralism remain the most suitable livelihood activity in dry lands and adaptation actions, which complement rather than substitute it, should be encouraged.enThesis