Gacheru, Jemimah Wanjiru2026-03-112026-03-112025-09https://ir-library.ku.ac.ke/handle/123456789/32695A Thesis Submitted in Partial Fulfilment of the Requirements for the Award of the Degree of Master of Environmental Science in the School of Agriculture and Environmental Sciences of Kenyatta University, September 2025 Supervisor: 1.Evelyn Wemali 2.Gladys GathuruClimate variability could be particularly damaging to smallholder farmers who depend on rain-fed agriculture. The study’s general objective was to assess the relationship between smallholder sweet potato production and climate variability in Gatundu North Sub-County. The specific objectives were to analyse temperature and rainfall trends and variability in the study area for the 30-year period between 1993 and 2022; to examine the relationship between climate variability and sweet potato production; to determine whether climate variability influences varietal diversity of sweet potatoes; and to assess the coping strategies adopted by smallholder sweet potato farmers against climate variability. The study used descriptive survey research design with a sample size (n) of 389. Structured questionnaires were administered on 292 randomly selected smallholder sweet potato farmers. Key informants (agricultural and meteorological officers) were interviewed. Monthly rainfall totals and monthly average maximum and minimum temperatures were obtained from KMD. Annual sweet potato production data was obtained from the Gatundu North Sub-County Agricultural Office. The Real Statistics Resource Pack was used to carry out trend analysis on rainfall and maximum and minimum temperature data using the Mann-Kendall Test and Sen’s Slope Estimator; and to carry out Pearson correlation on temperature, rainfall and sweet potato production. Shannon Diversity Index (H) was calculated to determine varietal diversity and species richness of sweet potatoes. Survey analysis was done on data collected through structured questionnaires to isolate running themes on the coping strategies. Results indicated that there was a decreasing but statistically insignificant trend (slope = -2.555, p-value = 0.669) in annual rainfall totals. Both monthly and annual rainfall was highly variable with CV>0.3. Annual average maximum and minimum temperatures had been increasing (slope = 0.065, p-value = 7.056E-07 and slope = 0.024, p-value = 0.032 respectively) but variability was negligible (CV < 0.3). Annual sweet potato production and annual rainfall had a weak negative correlation (r = -0.052, p = 0.865). The correlation between annual sweet potato production and annual average maximum and minimum temperatures was also weak and negative (r = -0.254, p = 0.399 and r = -0.199, p = 0.512 respectively). Climate variability influenced the choice of sweet potato varieties that smallholder farmers were growing (χ 2 =5.294 with 1 degree of freedom, p-value = 0.0214). The main coping strategies that were being utilized by smallholder sweet potato farmers were crop diversification (42.47%), irrigation (13.70%) and planting fast-maturing varieties (7.88%). The study concluded that there was a statistically insignificant decreasing trend in annual rainfall totals though variability was high on both monthly and annual time-scales; both annual average maximum and minimum temperatures had an increasing trend though monthly and annual variability was negligible; there was no significant relationship between changes in rainfall and temperature and sweet potato production; climate variability influenced varietal diversity of sweet potatoes and smallholder farmers had adopted coping strategies against climate change. It was recommended that MoALD and DoALI - Kiambu should prioritize a climate-smart sweet potato development program in the study area; DoALI - Kiambu should publicize the success of smallholder sweet potato farmers in coping with climate variability; KALRO should decentralize its services to sub-county and ward levels to enhance access to vines; and smallholder sweet potato farmers should enhance production by hosting on-farm demonstrations and participating in farmer field schoolsenThesis