Investing the Impact of Climate Variability and Change on Maize Yields in the Semi-Arid Lands of Lower Eastern Kenya

Abstract

The present study investigated the impact of climate variability and change on maize yields in the Semi-Arid Lands of lower Eastern Kenya. A major factor in rain-fed agriculture is the climate. The primary determinant of crop production in Kenya and other regions of the world has been climate variability and change. There hasn't been much study, though, on how climate variability affects maize yields in the Arid and Semi-Arid Lands (ASALs) in lower eastern Kenya counties. For the purpose of establishing a foundation for maize crop monitoring and modelling, the impact of three meteorological parameters on maize yields at various temporal and spatial scales was assessed. This paper argues that maize yields were declining at high levels in Machakos County followed by Kitui, Mwingi, and Makueni Counties. The maize yields Z-values and thus the effect of climate was predominately negative in the period 1994–2008 in all the counties. Rainfall trend analysis revealed that four of the six weather stations were declining up to 3 mm pa. Evidently there was upward warming of annual and seasonal temperatures at rate of 0.03°C pa. The study has confirmed that the arid and semi arid counties suffer from significant climate variability which has huge implications on maize yields and food security of lower eastern Kenya. Relationship between maize and rainfall was positive and negative, respectively, and was statistically significant. Maize yield has a pro- nounced declining negative trend in all the four coun- ties of lower eastern Kenya. Thus, to counter the adverse effects of climate change, it is necessary to climate-proof agricultural crops through adaptation strategies such as developing maize varieties that tolerate water stress and mature early, practice early planting, increase the awareness of climate change and its impacts on agriculture, and develop appropriate mitigation measures. These findings are crucial in planning appropriate adaptation mechanisms in support of enhancing resilience of maize production and food security.