Climate variability extremes, pastoralists adaptation strategies and future livestock productivity in the rangelands of Uganda

Abstract

A study was conducted to determine trends of variability and extremes of rainfall and temperature; pastoralists’ perceptions to the changes in rainfall and temperature extremes and predict future livestock productivity in the pastoral rangelands under changing climatic conditions. Data on daily rainfall, maximum and minimum temperatures from 1960 - 2013 were obtained from the National Meteorological Authority (NMA). Daily rainfall and temperature data were subjected to trend analysis using non-parametric Mann-Kendall tests. Rainfall and temperature extremes were analysed using RClimdex. Data to establish farmer’s perceptions to trends in climate extremes were collected from 240 respondents through household interviews using a pre-tested questionnaire. Data was analysed by descriptive statistics and multinomial logistic regression models using SPSS software. To predict future livestock productivity heat stress was determined and used to derive its implication on future milk production. Temperature –relative humidity index (THI) was used as an indicator of heat stress. ARIMA models in SPSS Expert modeller were used to predict futuristic trends of heat stress. Annual rainfall received showed non-significant increasing trends. Annual total wet days were increasing but not significant (p > 0.05). Consecutive wet days (CWD) were increasing while consecutive dry days, CDDs revealed increasing trends (p<0.05). Trends in annual temperature indices revealed significant increases in hot days (TX90p) and warm nights, TN90p (p < 0.05). The number of warmest nights (TNx) and hottest days (TXx) was significantly increasing (p < 0.05). Mean diurnal temperature range, DTR showed significant decreasing trends (p < 0.05). Severe droughts and floods, changes in day hot temperatures and warm nights, shift in start and cessation of rains, were the most perceived climate extremes. Key adaptation strategies pastoralists used included; fencing off grazing land, integration of crop into livestock production systems, diversification of livestock species kept, control of stocking rates and changing grazing time. Age of the household head, marital status of household head,